Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to the U.S. Navy Training and Testing Activities in the Northwest Training and Testing (NWTT) Study Area, 33914-34048 [2020-08533]

Download as PDF 33914 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 218 [200417–0114] RIN 0648–BJ30 Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to the U.S. Navy Training and Testing Activities in the Northwest Training and Testing (NWTT) Study Area National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Proposed rule; request for comments and information. AGENCY: NMFS has received a request from the U.S. Navy (Navy) to take marine mammals incidental to training and testing activities conducted in the Northwest Training and Testing (NWTT) Study Area. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue regulations and subsequent Letters of Authorization (LOAs) to the Navy to incidentally take marine mammals during the specified activities. NMFS will consider public comments prior to issuing any final rule and making final decisions on the issuance of the requested LOAs. Agency responses to public comments will be provided in the notice of the final decision. The Navy’s activities qualify as military readiness activities pursuant to the MMPA, as amended by the National Defense Authorization Act for Fiscal Year 2004 (2004 NDAA). DATES: Comments and information must be received no later than July 17, 2020. ADDRESSES: You may submit comments on this document, identified by NOAA– NMFS–2020–0055, by any of the following methods: • Electronic submission: Submit all electronic public comments via the Federal e-Rulemaking Portal. Go to www.regulations.gov/ #!docketDetail;D=NOAA-NMFS-20200055, click the ‘‘Comment Now!’’ icon, complete the required fields, and enter or attach your comments. • Mail: Submit written comments to Jolie Harrison, Chief, Permits and Conservation Division, Office of Protected Resources, National Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910. Instructions: Comments sent by any other method, to any other address or khammond on DSKJM1Z7X2PROD with PROPOSALS2 SUMMARY: VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 individual, or received after the end of the comment period, may not be considered by NMFS. All comments received are a part of the public record and will generally be posted for public viewing on www.regulations.gov without change. All personal identifying information (e.g., name, address), confidential business information, or otherwise sensitive information submitted voluntarily by the sender will be publicly accessible. NMFS will accept anonymous comments (enter ‘‘N/ A’’ in the required fields if you wish to remain anonymous). Attachments to electronic comments will be accepted in Microsoft Word, Excel, or Adobe PDF file formats only. A copy of the Navy’s application and other supporting documents and documents cited herein may be obtained online at: www.fisheries.noaa.gov/ national/marine-mammal-protection/ incidental-take-authorizations-militaryreadiness-activities. In case of problems accessing these documents, please use the contact listed here (see FOR FURTHER INFORMATION CONTACT). FOR FURTHER INFORMATION CONTACT: Wendy Piniak, Office of Protected Resources, NMFS, (301) 427–8401. SUPPLEMENTARY INFORMATION: Purpose of Regulatory Action These proposed regulations, issued under the authority of the MMPA (16 U.S.C. 1361 et seq.), would provide the framework for authorizing the take of marine mammals incidental to the Navy’s training and testing activities (which qualify as military readiness activities) from the use of sonar and other transducers, in-water detonations, and potential vessel strikes based on Navy movement in the NWTT Study Area. The Study Area includes air and water space off the coast of Washington, Oregon, and northern California; in the Western Behm Canal, Alaska; and portions of waters of the Strait of Juan de Fuca and Puget Sound, including Navy pierside and harbor locations in Puget Sound (see Figure 1–1 of the Navy’s rulemaking/LOA application). NMFS received an application from the Navy requesting seven-year regulations and authorizations to incidentally take individuals of multiple species of marine mammals (‘‘Navy’s rulemaking/LOA application’’ or ‘‘Navy’s application’’). Take is anticipated to occur by Level A harassment and Level B harassment as well as a very small number of serious injuries or mortalities incidental to the Navy’s training and testing activities. PO 00000 Frm 00002 Fmt 4701 Sfmt 4702 Background The MMPA prohibits the ‘‘take’’ of marine mammals, with certain exceptions. Sections 101(a)(5)(A) and (D) of the MMPA direct the Secretary of Commerce (as delegated to NMFS) to allow, upon request, the incidental, but not intentional, taking of small numbers of marine mammals by U.S. citizens who engage in a specified activity (other than commercial fishing) within a specified geographical region if certain findings are made and either regulations are issued or, if the taking is limited to harassment, the public is provided with notice of the proposed incidental take authorization and provided the opportunity to review and submit comments. An authorization for incidental takings shall be granted if NMFS finds that the taking will have a negligible impact on the species or stocks and will not have an unmitigable adverse impact on the availability of the species or stocks for taking for subsistence uses (where relevant). Further, NMFS must prescribe the permissible methods of taking and other means of effecting the least practicable adverse impact on the affected species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and on the availability of such species or stocks for taking for certain subsistence uses (referred to in this rule as ‘‘mitigation measures’’); and requirements pertaining to the monitoring and reporting of such takings. The MMPA defines ‘‘take’’ to mean to harass, hunt, capture, or kill, or attempt to harass, hunt, capture, or kill any marine mammal. The Preliminary Analysis and Negligible Impact Determination section below discusses the definition of ‘‘negligible impact.’’ The NDAA for Fiscal Year 2004 (2004 NDAA) (Pub. L. 108–136) amended section 101(a)(5) of the MMPA to remove the ‘‘small numbers’’ and ‘‘specified geographical region’’ provisions indicated above and amended the definition of ‘‘harassment’’ as applied to a ‘‘military readiness activity.’’ The definition of harassment for military readiness activities (Section 3(18)(B) of the MMPA) is (i) Any act that injures or has the significant potential to injure a marine mammal or marine mammal stock in the wild (Level A Harassment); or (ii) Any act that disturbs or is likely to disturb a marine mammal or marine mammal stock in the wild by causing disruption of natural behavioral patterns, including, but not limited to, migration, surfacing, nursing, breeding, feeding, or sheltering, to a E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 point where such behavioral patterns are abandoned or significantly altered (Level B harassment). In addition, the 2004 NDAA amended the MMPA as it relates to military readiness activities such that the least practicable adverse impact analysis shall include consideration of personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. More recently, Section 316 of the NDAA for Fiscal Year 2019 (2019 NDAA) (Pub. L. 115–232), signed on August 13, 2018, amended the MMPA to allow incidental take rules for military readiness activities under section 101(a)(5)(A) to be issued for up to seven years. Prior to this amendment, all incidental take rules under section 101(a)(5)(A) were limited to five years. Summary and Background of Request On March 11, 2019, NMFS received an application from the Navy for authorization to take marine mammals by Level A harassment and Level B harassment incidental to training and testing activities (which qualify as military readiness activities) from the use of sonar and other transducers and in-water detonations in the NWTT Study Area over a seven-year period beginning when the current authorization expires. In addition, the Navy requested incidental take authorization by serious injury or mortality for up to three takes of large whales from vessel strikes over the seven-year period. We received revised applications on June 6, 2019 and June 21, 2019 which provided revisions in the take number estimates and vessel strike analysis and Navy’s rulemaking/ LOA application was found to be adequate and complete. On August 6, 2019 (84 FR 38225), we published a notice of receipt (NOR) of application in the Federal Register, requesting comments and information related to the Navy’s request for 30 days. We reviewed and considered all comments and information received on the NOR in development of this proposed rule. On October 4, 2019, the Navy submitted an amendment to its application which incorporated new Southern Resident killer whale offshore density information, and on December 19, 2019, the Navy submitted an amendment to its application which incorporated revised testing activity numbers. The following types of training and testing, which are classified as military readiness activities pursuant to the MMPA, as amended by the 2004 NDAA, would be covered under the regulations and LOAs (if authorized): Antisubmarine warfare (sonar and other VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 transducers, underwater detonations), mine warfare (sonar and other transducers, underwater detonations), surface warfare (underwater detonations), and other testing and training (sonar and other transducers). The activities would not include pile driving/removal or use of air guns. This would be the third time NMFS has promulgated incidental take regulations pursuant to the MMPA relating to similar military readiness activities in the NWTT Study Area, following those effective from November 9, 2010 through November 8, 2015 (75 FR 69275; November 10, 2010) and from November 9, 2015 through November 8, 2020 (80 FR 73555; November 24, 2015). The Navy’s mission is to organize, train, equip, and maintain combat-ready naval forces capable of winning wars, deterring aggression, and maintaining freedom of the seas. This mission is mandated by Federal law (10 U.S.C. 8062), which requires the readiness of the naval forces of the United States. The Navy executes this responsibility in part by training and testing at sea, often in designated operating areas (OPAREA) and testing and training ranges. The Navy must be able to access and utilize these areas and associated sea space and air space in order to develop and maintain skills for conducting naval operations. The Navy’s testing activities ensure naval forces are equipped with well-maintained systems that take advantage of the latest technological advances. The Navy’s research and acquisition community conducts military readiness activities that involve testing. The Navy tests ships, aircraft, weapons, combat systems, sensors, and related equipment, and conducts scientific research activities to achieve and maintain military readiness. The Navy has been conducting training and testing activities in the NWTT Study Area for decades, with some activities dating back to at least the early 1900s. The tempo and types of training and testing activities have fluctuated because of the introduction of new technologies, the evolving nature of international events, advances in warfighting doctrine and procedures, and changes in force structure (e.g., organization of ships, submarines, aircraft, weapons, and personnel). Such developments influence the frequency, duration, intensity, and location of required training and testing activities, however the Navy’s proposed activities for the period of this proposed rule would be largely a continuation of ongoing activities. In addition to ongoing activities, the Navy is proposing some new training activities PO 00000 Frm 00003 Fmt 4701 Sfmt 4702 33915 such as torpedo exercise—submarine training and unmanned underwater vehicle training.1 The Navy is also proposing some new testing activities, including: At-sea sonar testing, mine countermeasure and neutralization testing, mine detection and classification testing, kinetic energy weapon testing, propulsion testing, undersea warfare testing, vessel signature evaluation, acoustic and oceanographic research, radar and other system testing, and simulant testing.2 The Navy’s rulemaking/LOA application reflects the most up-to-date compilation of training and testing activities deemed necessary by senior Navy leadership to accomplish military readiness requirements. The types and numbers of activities included in the proposed rule account for fluctuations in training and testing in order to meet evolving or emergent military readiness requirements. These proposed regulations would cover training and testing activities that would occur for a seven-year period following the expiration of the current MMPA authorization for the NWTT Study Area, which expires on November 8, 2020. Description of the Specified Activity The Navy requests authorization to take marine mammals incidental to conducting training and testing activities. The Navy has determined that acoustic and explosives stressors are most likely to result in impacts on marine mammals that could rise to the level of harassment, and NMFS concurs with this determination. Detailed descriptions of these activities are provided in Chapter 2 of the 2019 NWTT Draft Supplemental Environmental Impact Statement (SEIS)/ Overseas EIS (OEIS) (2019 NWTT DSEIS/OEIS) (https://www.nwtteis.com) and in the Navy’s rulemaking/LOA application (https:// www.fisheries.noaa.gov/national/ marine-mammal-protection/incidentaltake-authorizations-military-readinessactivities) and are summarized here. 1 Some of the activities included here are new to the 2019 NWTT DSEIS/OEIS, but are not new to the Study Area. TORPEX—SUB activity was previously analyzed in 2010 as part of the Sinking Exercise. The Sinking Exercise is no longer conducted in the NWTT Study Area and the TORPEX—SUB activity is now a separate activity included in the NWTT DSEIS/OEIS. Unmanned underwater vehicle activity was analyzed in 2010 as a testing activity, but is now being included as a training activity. 2 Mine detection and classification testing was analyzed in 2010 in the Inland waters, but was not previously analyzed in the Offshore waters. Vessel signature evaluation testing was analyzed in 2010 as a component to other activities, but is included in the list of new activities because it was not previously identified as an independent activity. E:\FR\FM\02JNP2.SGM 02JNP2 33916 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Dates and Duration The specified activities would occur at any time during the seven-year period of validity of the regulations. The proposed number of training and testing activities are described in the Detailed Description of the Specified Activities section (Tables 3 through 4). khammond on DSKJM1Z7X2PROD with PROPOSALS2 Geographical Region The NWTT Study Area is composed of established maritime operating and warning areas in the eastern North Pacific Ocean region, including areas of the Strait of Juan de Fuca, Puget Sound, and Western Behm Canal in southeastern Alaska. The Study Area includes air and water space within and VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 outside Washington state waters, within Alaska state waters, and outside state waters of Oregon and Northern California (Figure 1). The eastern boundary of the Offshore Area portion of the Study Area is 12 nautical miles (nmi) off the coastline for most of the Study Area, including southern Washington, Oregon, and Northern California. The Offshore Area includes the ocean all the way to the coastline only along that part of the Washington coast that lies beneath the airspace of W–237 and the Olympic Military Operating Area (MOA) and the Washington coastline north of the Olympic MOA. The Study Area includes four existing range complexes PO 00000 Frm 00004 Fmt 4701 Sfmt 4702 and facilities: The Northwest Training Range Complex, the Keyport Range Complex, Carr Inlet Operations Area, and the Southeast Alaska Acoustic Measurement Facility (Western Behm Canal, Alaska). In addition to these range complexes, the Study Area also includes Navy pierside locations where sonar maintenance and testing occurs as part of overhaul, modernization, maintenance, and repair activities at Naval Base Kitsap, Bremerton; Naval Base Kitsap, Bangor; and Naval Station Everett. Additional detail can be found in Chapter 2 of the Navy’s rulemaking/ LOA application. BILLING CODE 3510–22–P E:\FR\FM\02JNP2.SGM 02JNP2 33917 BILLING CODE 3510–22–C VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00005 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.002</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 33918 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Primary Mission Areas The Navy categorizes many of its training and testing activities into functional warfare areas called primary mission areas. The Navy’s proposed activities for NWTT generally fall into the following six primary mission areas: Air warfare; anti-submarine warfare; electronic warfare; expeditionary warfare; mine warfare; and surface warfare. Most activities conducted in NWTT are categorized under one of these primary mission areas; activities that do not fall within one of these areas are listed as ‘‘other activities.’’ Each warfare community (surface, subsurface, aviation, and expeditionary warfare) may train in some or all of these primary mission areas. The research and acquisition community also categorizes most, but not all, of its testing activities under these primary mission areas. A description of the sonar, munitions, targets, systems, and other material used during training and testing activities within these primary mission areas is provided in Appendix A (Navy Activities Descriptions) of the 2019 NWTT DSEIS/OEIS. The Navy describes and analyzes the effects of its activities within the 2019 NWTT DSEIS/OEIS. In its assessment, the Navy concluded that sonar and other transducers and underwater detonations were the stressors most likely to result in impacts on marine mammals that could rise to the level of harassment as defined under the MMPA. Therefore, the Navy’s rulemaking/LOA application provides the Navy’s assessment of potential effects from these stressors in terms of the various warfare mission areas in which they would be conducted. Those mission areas include the following: • Anti-submarine warfare (sonar and other transducers, underwater detonations); • expeditionary warfare; • mine warfare (sonar and other transducers, underwater detonations); • surface warfare (underwater detonations); and • other (sonar and other transducers). The Navy’s training and testing activities in air warfare and electronic warfare do not involve sonar and other transducers, underwater detonations, or any other stressors that could result in harassment, serious injury, or mortality of marine mammals. Therefore, the activities in air warfare and electronic warfare are not discussed further in this proposed rule, but are analyzed fully in the 2019 NWTT DSEIS/OEIS. Anti-Submarine Warfare The mission of anti-submarine warfare is to locate, neutralize, and VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 defeat hostile submarine forces that threaten Navy surface forces. Antisubmarine warfare can involve various assets such as aircraft, ships, and submarines which all search for hostile submarines. These forces operate together or independently to gain early warning and detection, and to localize, track, target, and attack submarine threats. Anti-submarine warfare training addresses basic skills such as detecting and classifying submarines, as well as evaluating sounds to distinguish between enemy submarines and friendly submarines, ships, and marine life. More advanced training integrates the full spectrum of anti-submarine warfare, from detecting and tracking a submarine to attacking a target using either exercise torpedoes (i.e., torpedoes that do not contain a warhead), or simulated weapons. These integrated antisubmarine warfare training exercises are conducted in coordinated, at-sea training events involving submarines, ships, and aircraft. Testing of anti-submarine warfare systems is conducted to develop new technologies and assess weapon performance and operability with new systems and platforms, such as unmanned systems. Testing uses ships, submarines, and aircraft to demonstrate capabilities of torpedoes (exercise and explosive), missiles, countermeasure systems, and underwater surveillance and communications systems. Tests may be conducted as part of a largescale training event involving submarines, ships, fixed-wing aircraft, and helicopters. These integrated training events offer opportunities to conduct research and acquisition activities and to train aircrew in the use of new or newly enhanced systems during a large-scale, complex exercise. Expeditionary Warfare The mission of expeditionary warfare is to provide security and surveillance in the littoral (at the shoreline), riparian (along a river), or coastal environments. Expeditionary warfare is wide ranging and includes defense of harbors, operation of remotely operated vehicles, defense against swimmers, and boarding/seizure operations. Expeditionary warfare training activities include underwater construction team training, dive and salvage operations, and insertion/extraction via air, surface, and subsurface platforms. Mine Warfare The mission of mine warfare is to detect, classify, and avoid or neutralize (disable) mines to protect Navy ships and submarines and to maintain free PO 00000 Frm 00006 Fmt 4701 Sfmt 4702 access to ports and shipping lanes. Mine warfare also includes training and testing in offensive mine laying to gain control of or deny the enemy access to sea space. Naval mines can be laid by ships, submarines, or aircraft. Mine warfare training includes exercises in which ships, aircraft, submarines, underwater vehicles, unmanned vehicles, or marine mammal detection systems search for mine shapes. Personnel train to destroy or disable mines by attaching underwater explosives to or near the mine or using remotely operated vehicles to destroy the mine. Towed influence mine sweep systems mimic a particular ship’s magnetic and acoustic signature, which would trigger a real mine, causing it to explode. Testing and development of mine warfare systems is conducted to improve acoustic, optical, and magnetic detectors intended to hunt, locate, and record the positions of mines for avoidance or subsequent neutralization. Mine warfare testing and development falls into two primary categories: Mine detection and classification, and mine countermeasure and neutralization testing. Mine detection and classification testing involves the use of air, surface, and subsurface vessels; it uses sonar, including towed and sidescan sonar, and unmanned vehicles to locate and identify objects underwater. Mine detection and classification systems are sometimes used in conjunction with a mine neutralization system. Mine countermeasure and neutralization testing includes the use of air, surface, and subsurface units and uses tracking devices, countermeasure and neutralization systems, and general purpose bombs to evaluate the effectiveness of neutralizing mine threats. Most neutralization tests use mine shapes, or non-explosive practice mines, to accomplish the requirements of the activity. For example, during a mine neutralization test, a previously located mine is destroyed or rendered nonfunctional using a helicopter or manned/unmanned surface vehiclebased system that may involve the deployment of a towed neutralization system. A small percentage of mine warfare activities require the use of highexplosives to evaluate and confirm the ability of the system or the crews conducting the training to neutralize a high-explosive mine under operational conditions. The majority of mine warfare systems are deployed by ships, helicopters, and unmanned vehicles. Tests may also be conducted in support of scientific research to support these new technologies. E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Surface Warfare The mission of surface warfare is to obtain control of sea space from which naval forces may operate, which entails offensive action against surface targets while also defending against aggressive actions by enemy forces. In the conduct of surface warfare, aircraft use guns, airlaunched cruise missiles, or other precision-guided munitions; ships employ naval guns and surface-tosurface missiles; and submarines attack surface ships using torpedoes or submarine-launched, anti-ship cruise missiles. Surface warfare training includes surface-to-surface gunnery and missile exercises, air-to-surface gunnery and missile exercises, submarine missile or torpedo launch events, and other munitions against surface targets. Testing of weapons used in surface warfare is conducted to develop new technologies and to assess weapon performance and operability with new systems and platforms, such as unmanned systems. Tests include various air-to-surface guns and missiles, surface-to-surface guns and missiles, and bombing tests. Testing events may be integrated into training activities to test aircraft or aircraft systems in the delivery of munitions on a surface target. In most cases the tested systems are used in the same manner in which they are used for training activities. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Other Activities The Navy conducts other training and testing activities in the Study Area that fall outside of the primary mission areas, but support overall readiness. Surface ship crews conduct Maritime Security Operations events, including maritime security escorts for Navy vessels such as Fleet Ballistic Missile Submarines; Visit, Board, Search, and Seizure; Maritime Interdiction Operations; Force Protection; AntiPiracy Operations, Acoustic Component Testing, Cold Water Support, and Hydrodynamic and Maneuverability testing. Anti-terrorism/Force-protection training will occur as small boat attacks against moored ships at one of the Navy’s piers inside Puget Sound. Pierside and at-sea maintenance of ship and submarine sonar is required for systems upkeep and systems evaluation. Description of Stressors The Navy uses a variety of sensors, platforms, weapons, and other devices, including ones used to ensure the safety of Sailors, to meet its mission. Training and testing with these systems may introduce acoustic (sound) energy or shock waves from explosives into the VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 environment. The proposed training and testing activities were evaluated to identify specific components that could act as stressors by having direct or indirect impacts on the environment. This analysis included identification of the spatial variation of the identified stressors. The following subsections describe the acoustic and explosive stressors for marine mammals and their habitat (including prey species) within the NWTT Study Area. Each description contains a list of activities that may generate the stressor. Stressor/resource interactions that were determined to have de minimis or no impacts (e.g., vessel noise, aircraft noise, weapons noise, and explosions in air) were not carried forward for analysis in the Navy’s rulemaking/LOA application. No Major Training Exercises (MTEs) or Sinking Exercise (SINKEX) events are proposed in the NWTT Study Area. NMFS reviewed the Navy’s analysis and conclusions on de minimis sources and finds them complete and supportable. Acoustic Stressors Acoustic stressors include acoustic signals emitted into the water for a specific purpose, such as sonar, other transducers (devices that convert energy from one form to another—in this case, into sound waves), incidental sources of broadband sound produced as a byproduct of vessel movement, aircraft transits, and use of weapons or other deployed objects. Explosives also produce broadband sound but are characterized separately from other acoustic sources due to their unique hazardous characteristics. Characteristics of each of these sound sources are described in the following sections. In order to better organize and facilitate the analysis of approximately 300 sources of underwater sound used in training and testing activities by the Navy, including sonar and other transducers and explosives, a series of source classifications, or source bins, were developed. The source classification bins do not include the broadband noise produced incidental to vessel and aircraft transits and weapons firing. Noise produced from vessel, aircraft, and weapons firing activities are not carried forward because those activities were found to have de minimis or no impacts, as stated above. The use of source classification bins provides the following benefits: • Provides the ability for new sensors or munitions to be covered under existing authorizations, as long as those sources fall within the parameters of a ‘‘bin;’’ PO 00000 Frm 00007 Fmt 4701 Sfmt 4702 33919 • Improves efficiency of source utilization data collection and reporting requirements anticipated under the MMPA authorizations; • Ensures a precautionary approach to all impact estimates, as all sources within a given class are modeled as the most impactful source (highest source level, longest duty cycle, or largest net explosive weight) within that bin; • Allows analyses to be conducted in a more efficient manner, without any compromise of analytical results; and • Provides a framework to support the reallocation of source usage (hours/ explosives) between different source bins, as long as the total numbers of takes remain within the overall analyzed and authorized limits. This flexibility is required to support evolving Navy training and testing requirements, which are linked to real world events. Sonar and Other Transducers Active sonar and other transducers emit non-impulsive sound waves into the water to detect objects, navigate safely, and communicate. Passive sonars differ from active sound sources in that they do not emit acoustic signals; rather, they only receive acoustic information about the environment, or listen. In this proposed rule, the terms sonar and other transducers will be used to indicate active sound sources unless otherwise specified. The Navy employs a variety of sonars and other transducers to obtain and transmit information about the undersea environment. Some examples are midfrequency hull-mounted sonars used to find and track enemy submarines; highfrequency small object detection sonars used to detect mines; high-frequency underwater modems used to transfer data over short ranges; and extremely high-frequency (greater than 200 kilohertz (kHz)) doppler sonars used for navigation, like those used on commercial and private vessels. The characteristics of these sonars and other transducers, such as source level, beam width, directivity, and frequency, depend on the purpose of the source. Higher frequencies can carry more information or provide more information about objects off which they reflect, but attenuate more rapidly. Lower frequencies attenuate less rapidly, so they may detect objects over a longer distance, but with less detail. Propagation of sound produced underwater is highly dependent on environmental characteristics such as bathymetry, bottom type, water depth, temperature, and salinity. The sound received at a particular location will be different than near the source due to the E:\FR\FM\02JNP2.SGM 02JNP2 33920 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules interaction of many factors, including propagation loss; how the sound is reflected, refracted, or scattered; the potential for reverberation; and interference due to multi-path propagation. In addition, absorption greatly affects the distance over which higher-frequency sounds propagate. The effects of these factors are explained in Appendix D (Acoustic and Explosive Concepts) of the 2019 NWTT DSEIS/ OEIS. Because of the complexity of analyzing sound propagation in the ocean environment, the Navy relies on acoustic models in its environmental analyses that consider sound source characteristics and varying ocean conditions across the Study Area. The sound sources and platforms typically used in naval activities analyzed in the Navy’s rulemaking/LOA application are described in Appendix A (Navy Activities Descriptions) of the 2019 NWTT DSEIS/OEIS. Sonars and other transducers used to obtain and transmit information underwater during Navy training and testing activities generally fall into several categories of use described below. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Anti-Submarine Warfare Sonar used during anti-submarine warfare training and testing would impart the greatest amount of acoustic energy of any category of sonar and other transducers analyzed in this proposed rule. Types of sonars used to detect potential enemy vessels include hull-mounted, towed, line array, sonobuoy, helicopter dipping, and torpedo sonars. In addition, acoustic targets and decoys (countermeasures) may be deployed to emulate the sound signatures of vessels or repeat received signals. Most anti-submarine warfare sonars are mid-frequency (1–10 kHz) because mid-frequency sound balances sufficient resolution to identify targets with distance over which threats can be identified. However, some sources may use higher or lower frequencies. Duty cycles can vary widely, from rarely used to continuously active. Anti-submarine warfare sonars can be wide-ranging in a search mode or highly directional in a track mode. Most anti-submarine warfare activities involving submarines or submarine targets would occur in waters greater than 600 feet (ft) deep due to safety concerns about running aground at shallower depths. Sonars used for antisubmarine warfare activities would typically be used beyond 12 nmi from shore. Exceptions include use of dipping sonar by helicopters, pierside testing and maintenance of systems while in port, and system checks while transiting to or from port. Communication Mine Warfare, Small Object Detection, and Imaging Classification of Sonar and Other Transducers Sonars used to locate mines and other small objects, as well as those used in imaging (e.g., for hull inspections or imaging of the seafloor), are typically high frequency or very high frequency. Higher frequencies allow for greater resolution and, due to their greater attenuation, are most effective over shorter distances. Mine detection sonar can be deployed (towed or vessel hullmounted) at variable depths on moving platforms (ships, helicopters, or unmanned vehicles) to sweep a suspected mined area. Hull-mounted anti-submarine sonars can also be used in an object detection mode known as ‘‘Kingfisher’’ mode. Sonars used for imaging are usually used in close proximity to the area of interest, such as pointing downward near the seafloor. Mine detection sonar use would be concentrated in areas where practice mines are deployed, typically in water depths less than 200 ft, and at temporary minefields close to strategic ports and harbors, or at targets of opportunity such as navigation buoys. Kingfisher mode on vessels is most likely to be used when transiting to and from port. Sound sources used for imaging could be used throughout the NWTT Study Area. Sonars and other transducers are grouped into classes that share an attribute, such as frequency range or purpose. As detailed below, classes are further sorted by bins based on the frequency or bandwidth; source level; and, when warranted, the application in which the source would be used. Unless stated otherwise, a reference distance of 1 meter (m) is used for sonar and other transducers. • Frequency of the non-impulsive acoustic source: Æ Low-frequency sources operate below 1 kHz; Æ Mid-frequency sources operate at and above 1 kHz, up to and including 10 kHz; Æ High-frequency sources operate above 10 kHz, up to and including 100 kHz; and Æ Very-high-frequency sources operate above 100 kHz but below 200 kHz. • Sound pressure level: Æ Greater than 160 decibels (dB) referenced to 1 micropascal (re: 1 mPa), but less than 180 dB re: 1 mPa; Æ Equal to 180 dB re: 1 mPa and up to 200 dB re: 1 mPa; and Æ Greater than 200 dB re: 1 mPa. • Application in which the source would be used: Æ Sources with similar functions that have similar characteristics, such as pulse length (duration of each pulse), beam pattern, and duty cycle. The bins used for classifying active sonars and transducers that are quantitatively analyzed in the Study Area are shown in Table 1. While general parameters or source characteristics are shown in the table, actual source parameters are classified. Navigation and Safety Similar to commercial and private vessels, Navy vessels employ navigational acoustic devices, including speed logs, Doppler sonars for ship positioning, and fathometers. These may be in use at any time for safe vessel operation. These sources are typically highly directional to obtain specific navigational data. Sound sources used to transmit data (such as underwater modems), provide location (pingers), or send a single brief release signal to bottom-mounted devices (acoustic release) may be used throughout the NWTT Study Area. These sources typically have low duty cycles and are usually only used when it is desirable to send a detectable acoustic message. TABLE 1—SONAR AND OTHER TRANSDUCERS QUANTITATIVELY ANALYZED IN THE NWTT STUDY AREA Source class category Bin Low-Frequency (LF): Sources that produce signals less than 1 kHz. Mid-Frequency (MF): Tactical and non-tactical sources that produce signals between 1 and 10 kHz. LF4 LF5 MF1 MF1K VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00008 Fmt 4701 Description LF sources equal to 180 dB and up to 200 dB. LF sources less than 180 dB. Hull-mounted surface ship sonars (e.g., AN/SQS–53C and AN/ SQS–60). Kingfisher mode associated with MF1 sonars. Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 33921 TABLE 1—SONAR AND OTHER TRANSDUCERS QUANTITATIVELY ANALYZED IN THE NWTT STUDY AREA—Continued Source class category Bin MF2 MF3 MF4 MF5 MF6 MF9 MF10 MF11 MF12 High-Frequency (HF): Tactical and non-tactical sources that produce signals between 10 and 100 kHz. HF1 HF3 HF4 HF5 HF6 Very High-Frequency (VHF): Tactical and non-tactical sources that produce signals greater than 100 kHz but less than 200 kHz. Anti-Submarine Warfare (ASW): Tactical sources (e.g., active sonobuoys and acoustic countermeasures systems) used during ASW training and testing activities. HF8 HF9 VHF1 VHF2 ASW1 ASW2 ASW3 Looking Sonar (FLS): Forward or upward looking object avoidance sonars used for ship navigation and safety. Acoustic Modems (M): Sources used to transmit data ................... Synthetic Aperture Sonars (SAS): Sonars used to form high-resolution images of the seafloor. Broadband Sound Sources (BB): Sonar systems with large frequency spectra, used for various purposes. 1 Formerly M3 SAS2 BB1 BB2 MF to HF mine countermeasure sonar. HF to VHF mine countermeasure sonar. khammond on DSKJM1Z7X2PROD with PROPOSALS2 ASW5 1 TORP1 TORP2 TORP3 FLS2 ASW2 in the 2015–2020 (Phase II) rulemaking. Explosive Stressors The near-instantaneous rise from ambient to an extremely high peak pressure is what makes an explosive shock wave potentially damaging. Farther from an explosive, the peak pressures decay and the explosive waves propagate as an impulsive, broadband sound. Several parameters influence the effect of an explosive: The weight of the explosive in the warhead, the type of explosive material, the boundaries and characteristics of the propagation medium, and the detonation depth in water. The net explosive weight, which is the explosive power of a charge expressed as the equivalent weight of trinitrotoluene (TNT), accounts for the first two parameters. The effects of these factors are explained in Appendix D (Acoustic and Explosive Concepts) of the 2019 VerDate Sep<11>2014 Hull-mounted surface ship sonars (e.g., AN/SQS–56). Hull-mounted submarine sonars (e.g., AN/BQQ–10). Helicopter-deployed dipping sonars (e.g., AN/AQS–22). Active acoustic sonobuoys (e.g., DICASS). Underwater sound signal devices (e.g., MK 84 SUS). Sources (equal to 180 dB and up to 200 dB) not otherwise binned. Active sources (greater than 160 dB, but less than 180 dB) not otherwise binned. Hull-mounted surface ship sonars with an active duty cycle greater than 80%. Towed array surface ship sonars with an active duty cycle greater than 80%. Hull-mounted submarine sonars (e.g., AN/BQQ–10). Other hull-mounted submarine sonars (classified). Mine detection, classification, and neutralization sonar (e.g., AN/ SQS–20). Active sources (greater than 200 dB) not otherwise binned. Sources (equal to 180 dB and up to 200 dB) not otherwise binned. Hull-mounted surface ship sonars (e.g., AN/SQS–61). Weapon-emulating sonar source. Active sources greater than 200 dB. Active sources with a source level less than 200 dB. MF systems operating above 200 dB. MF Multistatic Active Coherent sonobuoy (e.g., AN/SSQ–125). MF towed active acoustic countermeasure systems (e.g., AN/ SLQ–25). MF expendable active acoustic device countermeasures (e.g., MK 3). MF sonobuoys with high duty cycles. Lightweight torpedo (e.g., MK 46, MK 54, or Anti-Torpedo Torpedo). Heavyweight torpedo (e.g., MK 48). Heavyweight torpedo (e.g., MK 48). HF sources with short pulse lengths, narrow beam widths, and focused beam patterns. MF acoustic modems (greater than 190 dB). HF SAS systems. ASW4 Torpedoes (TORP): Active acoustic signals produced by torpedoes. Description 21:30 Jun 01, 2020 Jkt 250001 NWTT DSEIS/OEIS. The activities analyzed in the Navy’s rulemaking/LOA application that use explosives are described in Appendix A (Navy Activities Descriptions) of the 2019 NWTT DSEIS/OEIS. Explanations of the terminology and metrics used when describing explosives are provided in Appendix D (Acoustic and Explosive Concepts) of the 2019 NWTT DSEIS/ OEIS. Explosives in Water Explosive detonations during training and testing activities are associated with high-explosive munitions, including, but not limited to, bombs, missiles, naval gun shells, torpedoes, mines, demolition charges, and explosive sonobuoys. Explosive detonations during training and testing involving the use of high-explosive munitions, PO 00000 Frm 00009 Fmt 4701 Sfmt 4702 including bombs, missiles, and naval gun shells, could occur in the air or near the water’s surface. Explosive detonations associated with torpedoes and explosive sonobuoys would occur in the water column; mines and demolition charges could be detonated in the water column or on the ocean bottom. Detonations would typically occur in waters greater than 200 ft in depth, and greater than 50 nmi from shore, with the exception of mine countermeasure and neutralization testing proposed in the Offshore Area, and existing mine warfare areas in Inland Waters (i.e., Crescent Harbor and Hood Canal Explosive Ordnance Disposal Training Ranges). Mine countermeasure and neutralization testing is a new proposed testing activity that would occur closer to shore than other in-water explosive activities E:\FR\FM\02JNP2.SGM 02JNP2 33922 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules analyzed in the 2015 NWTT Final EIS/ OEIS for the Offshore Area of the NWTT Study Area. This activity would occur in waters 3 nmi or greater from shore in the Quinault Range Site (outside the Olympic Coast National Marine Sanctuary), or 12 nmi or greater from shore elsewhere in the Offshore Area. Two of the three events would involve the use of explosives, and would typically occur in water depths shallower than 1,000 ft. The two multiday events (1–10 days per event) would include up to 36 E4 explosives (>2.5–5 lb net explosive weight) and 5 E7 explosives (>20–60 lb net explosive weight). In order to better organize and facilitate the analysis of explosives used by the Navy during training and testing that could detonate in water or at the water surface, explosive classification bins were developed. The use of explosive classification bins provides the same benefits discussed above and as described for acoustic source classification bins in Section 1.4.1 (Acoustic Stressors) of the Navy’s rulemaking/LOA application. Explosives detonated in water are binned by net explosive weight. The bins of explosives that are proposed for use in the Study Area are shown in Table 2 below. TABLE 2—EXPLOSIVE SOURCES QUANTITATIVELY ANALYZED THAT COULD BE USED UNDERWATER OR AT THE WATER SURFACE IN THE STUDY AREA Bin Net explosive weight (lb) E1 .......................................... E2 .......................................... E3 .......................................... E4 .......................................... E5 .......................................... E7 .......................................... E8 .......................................... E10 ........................................ E11 ........................................ 0.1–0.25 >0.25–0.5 >0.5–2.5 >2.5–5 >5–10 >20–60 >60–100 >250–500 >500–650 Modeled detonation depths (ft) Example explosive source Medium-caliber projectiles ................................................... Medium-caliber projectiles ................................................... Explosive Ordnance Disposal Mine Neutralization ............. Mine Countermeasure and Neutralization ........................... Large-caliber projectile ........................................................ Mine Countermeasure and Neutralization ........................... Lightweight torpedo ............................................................. 1,000 lb bomb ...................................................................... Heavyweight torpedo ........................................................... 0.3, 60. 0.3. 33, 60. 197, 262, 295, 394. 0.3. 33, 98, 230, 295. 150. 0.3. 300, 656. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Notes: Net Explosive Weight refers to the equivalent amount of TNT, the actual weight of a munition may be larger due to other components; in = inch(es), lb = pound(s), ft = feet. Propagation of explosive pressure waves in water is highly dependent on environmental characteristics such as bathymetry, bottom type, water depth, temperature, and salinity, which affect how the pressure waves are reflected, refracted, or scattered; the potential for reverberation; and interference due to multi-path propagation. In addition, absorption greatly affects the distance over which higher-frequency components of explosive broadband noise can propagate. Appendix D (Acoustic and Explosive Concepts) of the 2019 NWTT DSEIS/OEIS explains the characteristics of explosive detonations and how the above factors affect the propagation of explosive energy in the water. Because of the complexity of analyzing sound propagation in the ocean environment, the Navy relies on acoustic models in its environmental analyses that consider sound source characteristics and varying ocean conditions across the Study Area. supersonic speed from the detonation. The casing fragments will be ejected at velocities much greater than debris from any target due to the proximity of the casing to the explosive material. Risk of fragment injury reduces exponentially with distance as the fragment density is reduced. Fragments underwater tend to be larger than fragments produced by inair explosions (Swisdak and Montaro, 1992). Underwater, the friction of the water would quickly slow these fragments to a point where they no longer pose a threat. Opposingly, the blast wave from an explosive detonation moves efficiently through the seawater. Because the ranges to mortality and injury due to exposure to the blast wave are likely to far exceed the zone where fragments could injure or kill an animal, the ranges for assessing the likelihood of mortality and injury from a blast, which are also used to inform mitigation zones, are assumed to encompass risk due to fragmentation. Explosive Fragments NMFS also considered the chance that a vessel utilized in training or testing activities could strike a marine mammal. Vessel strikes have the potential to result in incidental take from serious injury and/or mortality. Vessel strikes are not specific to any particular training or testing activity, but rather are a limited, sporadic, and incidental result of Navy vessel movement during training and testing Marine mammals could be exposed to fragments from underwater explosions associated with the specified activities. When explosive ordnance (e.g., bomb or missile) detonates, fragments of the weapon are thrown at high-velocity from the detonation point, which can injure or kill marine mammals if they are struck. These fragments may be of variable size and are ejected at VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Other Stressor—Vessel Strike PO 00000 Frm 00010 Fmt 4701 Sfmt 4702 activities within a Study Area. Vessel strikes from commercial, recreational, and military vessels are known to seriously injure and occasionally kill cetaceans (Abramson et al., 2011; Berman-Kowalewski et al., 2010; Calambokidis, 2012; Douglas et al., 2008; Laggner, 2009; Lammers et al., 2003; Van der Hoop et al., 2012; Van der Hoop et al., 2013), although reviews of the literature on ship strikes mainly involve collisions between commercial vessels and whales (Jensen and Silber, 2003; Laist et al., 2001). Vessel speed, size, and mass are all important factors in determining both the potential likelihood and impacts of a vessel strike to marine mammals (Conn and Silber, 2013; Gende et al., 2011; Silber et al., 2010; Vanderlaan and Taggart, 2007; Wiley et al., 2016). For large vessels, speed and angle of approach can influence the severity of a strike. Navy vessels transit at speeds that are optimal for fuel conservation and to meet training and testing requirements. Vessels used as part of the proposed Specified Activities include ships, submarines, unmanned vessels, and boats ranging in size from small, 22 ft (7 m) rigid hull inflatable boats to aircraft carriers with lengths up to 1,092 ft (333 m). The average speed of large Navy ships ranges between 10 and 15 knots (kn) and submarines generally operate at speeds in the range of 8 to 13 kn, while a few specialized vessels can travel at faster speeds. Small craft (for E:\FR\FM\02JNP2.SGM 02JNP2 33923 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules purposes of this analysis, less than 60 ft (18 m) in length) have much more variable speeds (0 to 50+ kn, dependent on the activity), but generally range from 10 to 14 kn. From unpublished Navy data, average median speed for large Navy ships in the other Navy ranges from 2011–2015 varied from 5 to 10 kn with variations by ship class and location (i.e., slower speeds close to the coast). Similar patterns would occur in the NWTT Study Area. A full description of Navy vessels that are used during training and testing activities can be found in Chapter 2 (Description of Proposed Action and Alternatives) of the 2019 NWTT DSEIS/ OEIS. While these speeds are representative of most events, some vessels need to temporarily operate outside of these parameters for certain times or during certain activities. For example, to produce the required relative wind speed over the flight deck, an aircraft carrier engaged in flight operations must adjust its speed through the water accordingly. Conversely, there are other instances, such as launch and recovery of a small rigid hull inflatable boat; vessel boarding, search, and seizure training events; or retrieval of a target when vessels will be dead in the water or moving slowly ahead to maintain steerage. Large Navy vessels (greater than 60 ft (18 m) in length) within the offshore areas of range complexes and testing ranges operate differently from commercial vessels in ways that may reduce potential whale collisions. Surface ships operated by or for the Navy have multiple personnel assigned to stand watch at all times, when a ship or surfaced submarine is moving through the water (underway). A primary duty of personnel standing watch on surface ships is to detect and report all objects and disturbances sighted in the water that may indicate a threat to the vessel and its crew, such as debris, a periscope, surfaced submarine, or surface disturbance. Per vessel safety requirements, personnel standing watch also report any marine mammals sighted in the path of the vessel as a standard collision avoidance procedure. All vessels proceed at a safe speed so they can take proper and effective action to avoid a collision with any sighted object or disturbance, and can be stopped within a distance appropriate to the prevailing circumstances and conditions. Detailed Description of Proposed Activities Proposed Training and Testing Activities The training and testing activities that the Navy proposes to conduct in the NWTT Study Area are summarized in Table 3 (training) and Table 4 (testing). The tables are organized according to primary mission areas and include the activity name, associated stressor(s) of Navy’s activities, description and duration of the activity, sound source bin, the areas where the activities are conducted in the NWTT Study Area, and the number of activities. Under the ‘‘Annual # of Events’’ column, events show either a single number or a range of numbers to indicate the maximum number of times that activity could occur during any single year. The ‘‘7Year # of Events’’ is the maximum number of times an activity would occur over the 7-year period of proposed regulations. For further information regarding the primary platform used (e.g., ship or aircraft type) see Appendix A (Training and Testing Activities Descriptions) of the 2019 NWTT DSEIS/ OEIS. The Navy’s proposed activities reflect a representative year of training and testing to account for the natural fluctuation of training and testing cycles and deployment schedules that generally prevents the maximum level of activities from occurring year after year in any 7-year period. As shown in the tables of activities, the number of some activities may vary from year to year, and the level of variability can differ by activity. Still, the annual analysis assumes a ‘‘maximum’’ year. For the purposes of this request, the Navy assumes that some unit-level training would be conducted using synthetic means (e.g., simulators). Additionally, the request assumes that some unit-level active sonar training and some testing will be completed during other scheduled activities. TABLE 3—PROPOSED TRAINING ACTIVITIES ANALYZED FOR THE SEVEN-YEAR PERIOD IN THE NWTT STUDY AREA Stressor category Annual # of events 7-Year # of events Offshore Area >12 nmi from land. 0–2 5 MF4, MF5 Offshore Area >12 nmi from land. 0–2 5 ASW2, ASW5, MF5, TORP1. ASW3, MF1, MF11. HF1, MF3 Offshore Area >12 nmi from land. 373 2,611 Offshore Area ........... 62 434 Offshore Area ........... 75–100 595 Inland Waters ............ 0–1 5 Typical duration Source bin Submarine crews search for, track, and detect submarines. Event would include one MK–48 torpedo used during this event. Helicopter crews search for, track, and detect submarines. 8 hours ......... TORP2 .... 2–4 hours ..... Maritime patrol aircraft crews search for, track, and detect submarines. 2–8 hours ..... Surface ship crews search for, track, and detect submarines. 2–4 hours ..... Submarine crews search for, track, and detect submarines. 8 hours ......... Activity Description Location Anti-Submarine Warfare Acoustic; Explosive Acoustic .................. Acoustic .................. Acoustic .................. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Acoustic .................. Torpedo Exercise— Submarine (TORPEX—Sub). Tracking Exercise— Helicopter (TRACKEX—Helo). Tracking Exercise— Maritime Patrol Aircraft (TRACKEX— MPA). Tracking Exercise— Ship (TRACKEX— Ship). Tracking Exercise— Submarine (TRACKEX—Sub). Mine Warfare Acoustic .................. VerDate Sep<11>2014 Civilian Port Defense—Homeland Security Anti-Terrorism/Force Protection Exercises. 21:30 Jun 01, 2020 Maritime security personnel train to protect civilian ports and harbors against enemy efforts to interfere with access to those ports. Jkt 250001 PO 00000 Frm 00011 Fmt 4701 Multiple days Sfmt 4702 HF4, SAS2. E:\FR\FM\02JNP2.SGM 02JNP2 33924 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 3—PROPOSED TRAINING ACTIVITIES ANALYZED FOR THE SEVEN-YEAR PERIOD IN THE NWTT STUDY AREA— Continued Annual # of events 7-Year # of events 12 84 Offshore Area (W– 237) >50 nmi from land. Offshore Area >50 nmi from land. * 0–2 5 * 90 504 E10 .......... Offshore Area (W– 237) >50 nmi from land. 0–2 5 NBK Bangor, NBK Bremerton, and Offshore Area >12 nmi from land. NBK Bremerton, NS Everett, and Offshore Area >12 nmi from land. Inland Waters, Offshore Area. 26 182 25 175 60 420 Stressor category Activity Description Typical duration Source bin Location Explosive ................ Mine Neutralization— Explosive Ordnance Disposal (EOD). Personnel disable threat mines using explosive charges. Up to 4 hours E3 ............ Crescent Harbor EOD Training Range, Hood Canal EOD Training Range. Fixed-wing aircrews deliver bombs against surface targets. 1 hour ........... E10 .......... Surface ship crews fire large- and mediumcaliber guns at surface targets. Up to 3 hours E1, E2, E5 Fixed-wing aircrews simulate firing precision-guided missiles, using captive air training missiles (CATMs) against surface targets. Some activities include firing a missile with a high-explosive (HE) warhead. 2 hours ......... Surface Warfare Explosive ................ Explosive ................ Explosive ................ Bombing Exercise (Air-to-Surface) (BOMBEX [A–S]). Gunnery Exercise (Surface-to-Surface)—Ship (GUNEX [S–S]— Ship). Missile Exercise (Airto-Surface) (MISSILEX [A–S]). Other Training Acoustic .................. Submarine Sonar Maintenance. Maintenance of submarine sonar and other system checks are conducted pierside or at sea. Up to 1 hour LF5, MF3 Acoustic .................. Surface Ship Sonar Maintenance. Maintenance of surface ship sonar and other system checks are conducted pierside or at sea. Up to 4 hours MF1 ......... Acoustic .................. Unmanned Underwater Vehicle Training. Unmanned underwater vehicle certification involves training with unmanned platforms to ensure submarine crew proficiency. Tactical development involves training with various payloads for multiple purposes to ensure that the systems can be employed effectively in an operational environment. Up to 24 hours. FLS2, M3 * (Counts only the explosive events). TABLE 4—PROPOSED TESTING ACTIVITIES ANALYZED FOR THE SEVEN-YEAR PERIOD IN THE NWTT STUDY AREA Stressor category Activity Typical duration Description Annual # of events 7-Year # of events Offshore Area .......... 44 308 Offshore Area .......... Inland Waters (DBRC). 4 4–6 28 34 14 98 29 203 1 5 Source bin Location ASW1, ASW2, ASW3, ASW5, MF1K, MF4, MF5, MF10, MF11, MF12, TORP1. ASW3, HF1, HF5, M3, MF3. ASW3, HF5, TORP1. ASW3, ASW4, HF8, MF1, TORP2. ASW3, ASW4 .... Naval Sea Systems Command Testing Activities khammond on DSKJM1Z7X2PROD with PROPOSALS2 Anti-Submarine Warfare: Acoustic ................... Anti-Submarine Warfare Testing. Ships and their supporting platforms (rotary-wing aircraft and unmanned aerial systems) detect, localize, and prosecute submarines. 4–8 hours of active sonar use. Acoustic ................... At-Sea Sonar Testing. At-sea testing to ensure systems are fully functional in an open ocean environment. From 4 hours to 11 days. Acoustic ................... Countermeasure Testing. Countermeasure testing involves the testing of systems that will detect, localize, and track incoming weapons, including marine vessel targets. Countermeasures may be systems to obscure the vessel’s location or systems to rapidly detect, track, and counter incoming threats. Testing includes surface ship torpedo defense systems and marine vessel stopping payloads. From 4 hours to 6 days. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00012 Fmt 4701 Sfmt 4702 ASW4 ................ E:\FR\FM\02JNP2.SGM Offshore Area (QRS). Inland Waters (DBRC, Keyport Range Site). Western Behm Canal, AK. 02JNP2 33925 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 4—PROPOSED TESTING ACTIVITIES ANALYZED FOR THE SEVEN-YEAR PERIOD IN THE NWTT STUDY AREA— Continued 7-Year # of events 88–99 635 1–2 10 4 28 Offshore Area .......... 22 154 Inland Waters (DBRC). 61 427 3 3 15 13 1 42 7 294 38–39 371– 379 269 2,615 1–12 27 1 3 7 21 13–18 99 4 28 1 7 Description Typical duration Source bin Location Acoustic ................... Pierside-Sonar Testing. Up to 3 weeks Acoustic ................... Submarine Sonar Testing/Maintenance. ASW3, HF3, MF1, MF2, MF3, MF9, MF10, MF12. HF6, MF9 .......... Inland Waters (NS Everett, NBK Bangor, NBK Bremerton). Western Behm Canal, AK. Acoustic; Explosive .. Torpedo (Explosive) Testing. Pierside testing to ensure systems are fully functional in a controlled pierside environment prior to at-sea test activities. Pierside, moored, and underway testing of submarine systems occurs periodically following major maintenance periods and for routine maintenance. Air, surface, or submarine crews employ explosive and non-explosive torpedoes against artificial targets. Offshore Area >50 nmi from land. Acoustic ................... Torpedo (Non-explosive) Testing. Air, surface, or submarine crews employ non-explosive torpedoes against targets, submarines, or surface vessels. Up to 2 weeks E8, E11, ASW3, HF1, HF6, MF1, MF3, MF4, MF5, MF6, TORP1, TORP2. ASW3, ASW4, HF1, HF5, HF6, MF1, MF3, MF4, MF5, MF6, MF9, MF10, TORP1, TORP2. HF6, LF4, TORP1, TORP2, TORP3. Mine Warfare: Acoustic; Explosive .. Acoustic ................... Unmanned Systems: Acoustic ................... Vessel Evaluation: Acoustic ................... Other Testing: Acoustic ................... khammond on DSKJM1Z7X2PROD with PROPOSALS2 Annual # of events Activity Stressor category 1–2 hours during daylight only. Mine Countermeasure and Neutralization Testing. Mine Detection and Classification Testing. Air, surface, and subsurface vessels neutralize threat mines and mine-like objects. Air, surface, and subsurface vessels and systems detect and classify mines and mine-like objects. Vessels also assess their potential susceptibility to mines and mine-like objects. 1–10 days ..... E4, E7, HF4 ....... HF4 .................... Offshore Area .......... Inland Waters .......... Up to 24 days BB1, BB2, LF4 .. BB1, BB2, HF4, LF4. Offshore Area (QRS). Inland Waters (DBRC, Keyport Range Site). Unmanned Underwater Vehicle Testing. Testing involves the production or upgrade of unmanned underwater vehicles. This may include testing of mission capabilities (e.g., mine detection), evaluating the basic functions of individual platforms, or conducting complex events with multiple vehicles. Typically 1–2 days, up to multiple months. FLS2, HF5, TORP1, VHF1. DS3, FLS2, HF5, HF9, M3, SAS2, VHF1, TORP1. Offshore Area (QRS). Inland Waters (DBRC, Keyport Range Site, Carr Inlet). Undersea Warfare Testing. Ships demonstrate capability of countermeasure systems and underwater surveillance, weapons engagement, and communications systems. This tests ships’ ability to detect, track, and engage undersea targets. Up to 10 days ASW3, ASW4, HF4, MF1, MF4, MF5, MF6, MF9, TORP1, TORP2. Offshore Area .......... Acoustic and Oceanographic Research. Research using active transmissions from sources deployed from ships, aircraft, and unmanned underwater vehicles. Research sources can be used as proxies for current and future Navy systems. Various surface vessels, moored equipment, and materials are tested to evaluate performance in the marine environment. Fleet training for divers in a cold water environment, and other diver training related to Navy divers supporting range/test site operations and maintenance. Up to 14 days LF4, MF9 ........... Offshore Area (QRS). Inland Waters (DBRC, Keyport Range Site). Acoustic ................... Acoustic Component Testing. Acoustic ................... Cold Water Support VerDate Sep<11>2014 Up to 3 weeks 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00013 Fmt 4701 1 day to mulHF3, HF6, LF5, tiple months. MF9. Western Behm Canal, AK. 8 hours ......... Inland Waters (Keyport Range Site, DBRC, Carr Inlet). Western Behm Canal, AK. Sfmt 4702 HF6 .................... E:\FR\FM\02JNP2.SGM 02JNP2 33926 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 4—PROPOSED TESTING ACTIVITIES ANALYZED FOR THE SEVEN-YEAR PERIOD IN THE NWTT STUDY AREA— Continued Stressor category Acoustic ................... Acoustic ................... Activity Typical duration Description Post-Refit Sea Trial Following periodic maintenance periods or repairs, sea trials are conducted to evaluate submarine propulsion, sonar systems, and other mechanical tests. Semi-Stationary Semi-stationary equipment (e.g., Equipment Testing. hydrophones) is deployed to determine functionality. Source bin Location 8 hours ......... HF9, M3, MF10 Inland Waters (DBRC). From 10 minutes to multiple days. HF6, HF9, LF4, MF9, VHF2. HF6, HF9 ........... Inland Waters (DBRC, Keyport Range Site). Western Behm Canal, AK. Annual # of events 7-Year # of events 30 210 120 840 2–3 12 8 56 Naval Air Systems Command Testing Activities Anti-Submarine Warfare: Acoustic; Explosive .. Tracking Test—Mari- The test evaluates the sensors time Patrol Aircraft. and systems used by maritime patrol aircraft to detect and track submarines and to ensure that aircraft systems used to deploy the tracking systems perform to specifications and meet operational requirements. Summary of Acoustic and Explosive Sources Analyzed for Training and Testing Tables 5 through 8 show the acoustic and explosive source classes, bins, and quantity used in either hours or counts associated with the Navy’s proposed 4–8 flight hours. E1, E3, ASW2, ASW5, MF5, MF6. training and testing activities over a seven-year period in the NWTT Study Area that were analyzed in the Navy’s rulemaking/LOA application. Table 5 describes the acoustic source classes (i.e., low-frequency (LF), mid-frequency (MF), and high-frequency (HF)) and Offshore Area .......... numbers that could occur over seven years under the proposed training activities. Acoustic source bin use in the proposed activities would vary annually. The seven-year totals for the proposed training activities take into account that annual variability. TABLE 5—ACOUSTIC SOURCE CLASS BINS ANALYZED AND NUMBERS USED FOR SEVEN-YEAR PERIOD FOR TRAINING ACTIVITIES IN THE NWTT STUDY AREA Source class category Bin Low-Frequency (LF): Sources that produce signals less than 1 kHz. Mid-Frequency (MF): Tactical and non-tactical sources that produce signals between 1 and 10 kHz. Description Unit LF5 LF sources less than 180 dB .......................... H 1 5 MF1 Hull-mounted surface ship sonars (e.g., AN/ SQS–53C and AN/SQS–61). H 164 1,148 MF3 Hull-mounted submarine sonars (e.g., AN/ BQQ–10). Helicopter-deployed dipping sonars (e.g., AN/ AQS–22 and AN/AQS–13). Active acoustic sonobuoys (e.g., DICASS) ..... Hull-mounted surface ship sonars with an active duty cycle greater than 80%. Hull-mounted submarine sonars (e.g., AN/ BQQ–10). H 70 490 H 0–1 1 C H 918–926 16 6,443 112 H 48 336 Mine detection, classification, and neutralization sonar (e.g., AN/SQS–20). MF Multistatic Active Coherent sonobuoy (e.g., AN/SSQ–125). H 0–65 269 C 350 2,450 MF towed active acoustic countermeasure systems (e.g., AN/SLQ–25). MF sonobuoys with high duty cycles .............. Lightweight torpedo (e.g., MK 46, MK 54, or Anti-Torpedo Torpedo). H 86 602 H C 50 16 350 112 C H 0–2 240 5 1,680 MF4 MF5 MF11 High-Frequency (HF): Tactical and non-tactical sources that produce signals between 10 and 100 kHz. HF1 HF4 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Anti-Submarine Warfare (ASW): Tactical sources (e.g., active sonobuoys and acoustic countermeasures systems) used during ASW training and testing activities. ASW2 ASW3 Torpedoes (TORP): Source classes associated with the active acoustic signals produced by torpedoes. Forward Looking Sonar (FLS): Forward or upward looking object avoidance sonars used for ship navigation and safety. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 ASW5 TORP1 TORP2 FLS2 PO 00000 Heavyweight torpedo (e.g., MK 48) ................ HF sources with short pulse lengths, narrow beam widths, and focused beam patterns. Frm 00014 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Annual 7-Year total 33927 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 5—ACOUSTIC SOURCE CLASS BINS ANALYZED AND NUMBERS USED FOR SEVEN-YEAR PERIOD FOR TRAINING ACTIVITIES IN THE NWTT STUDY AREA—Continued Source class category Bin Acoustic Modems (M): Systems used to transmit data through the water. Synthetic Aperture Sonars (SAS): Sonars in which active acoustic signals are post-processed to form high-resolution images of the seafloor. Description Unit Annual 7-Year total M3 MF acoustic modems (greater than 190 dB) .. H 30 210 SAS2 HF SAS systems ............................................. H 0–561 2,353 Notes: H = hours; C = count. Table 6 describes the acoustic source classes and numbers that could occur over seven years under the proposed testing activities. Acoustic source bin use in the proposed activities would vary annually. The seven-year totals for the proposed testing activities take into account that annual variability. TABLE 6—ACOUSTIC SOURCE CLASS BINS ANALYZED AND NUMBERS USED FOR SEVEN-YEAR PERIOD FOR TESTING ACTIVITIES IN THE NWTT STUDY AREA Source class category Bin Low-Frequency (LF): Sources that produce signals less than 1 kHz. Mid-Frequency (MF): Tactical and non-tactical sources that produce signals between 1 and 10 kHz. Description Unit LF4 LF sources equal to 180 dB and up to 200 dB H 177 1,239 LF5 MF1 LF sources less than 180 dB .......................... Hull-mounted surface ship sonars (e.g., AN/ SQS–53C and AN/SQS–61). H H 0–18 20–169 23 398 MF1K MF2 Kingfisher mode associated with MF1 sonars Hull-mounted surface ship sonars (e.g., AN/ SQS–56). Hull-mounted submarine sonars (e.g., AN/ BQQ–10). Helicopter-deployed dipping sonars (e.g., AN/ AQS–22 and AN/AQS–13). Active acoustic sonobuoys (e.g., DICASS) ..... Active underwater sound signal devices (e.g., MK 84 SUS). Active sources (equal to 180 dB and up to 200 dB) not otherwise binned. Active sources (greater than 160 dB, but less than 180 dB) not otherwise binned. Hull-mounted surface ship sonars with an active duty cycle greater than 80 percent. Towed array surface ship sonars with an active duty cycle greater than 80 percent. Hull-mounted submarine sonars (e.g., AN/ BQQ–10). H H 48 32 336 224 H 34–36 239 H 41–50 298 C C 300–673 60–232 2,782 744 H 644–959 5,086 H 886 6,197 H 48 336 H 100 700 H 10 68 Other hull-mounted submarine sonars (classified). Mine detection, classification, and neutralization sonar (e.g., AN/SQS–20). Active sources (greater than 200 dB) not otherwise binned. Active sources (equal to 180 dB and up to 200 dB) not otherwise binned. Hull-mounted surface ship sonars (e.g., AN/ SQS–61). Weapon emulating sonar source .................... Very high frequency sources greater than 200 dB. H 1–19 30 H 1,860–1,868 11,235 H 352–400 2,608 H 1,705–1,865 12,377 H 24 168 H H 257 320 1,772 2,240 Active sources with a frequency greater than 100 kHz, up to 200 kHz with a source level less than 200 dB. MF systems operating above 200 dB ............. H 135 945 H 80 560 MF systems operating above 200 dB ............. MF towed active acoustic countermeasure systems (e.g., AN/SLQ–25). C H 240 487–1,015 1,680 4,091 MF3 MF4 MF5 MF6 MF9 MF10 MF11 MF12 High-Frequency (HF): Tactical and non-tactical sources that produce signals between 10 and 100 kHz. HF1 HF3 HF4 HF5 HF6 khammond on DSKJM1Z7X2PROD with PROPOSALS2 HF8 Very High-Frequency (VHF): Tactical and nontactical sources that produce signals greater than 100 kHz but less than 200 kHz. HF9 VHF1 VHF2 Anti-Submarine Warfare (ASW): Tactical sources (e.g., active sonobuoys and acoustic countermeasures systems) used during ASW training and testing activities. ASW1 ASW2 ASW3 VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00015 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Annual 7-Year total 33928 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 6—ACOUSTIC SOURCE CLASS BINS ANALYZED AND NUMBERS USED FOR SEVEN-YEAR PERIOD FOR TESTING ACTIVITIES IN THE NWTT STUDY AREA—Continued Source class category Bin ASW4 Torpedoes (TORP): Source classes associated with the active acoustic signals produced by torpedoes. Forward Looking Sonar (FLS): Forward or upward looking object avoidance sonars used for ship navigation and safety. Acoustic Modems (M): Systems used to transmit data through the water. Synthetic Aperture Sonars (SAS): Sonars in which active acoustic signals are post-processed to form high-resolution images of the seafloor. Broadband Sound Sources (BB): Sonar systems with large frequency spectra, used for various purposes. ASW5 TORP1 Description Unit Annual 7-Year total MF expendable active acoustic device countermeasures (e.g., MK 3). MF sonobuoys with high duty cycles .............. Lightweight torpedo (e.g., MK 46, MK 54, or Anti-Torpedo Torpedo). C 1,349–1,389 9,442 H C 80 298–360 560 2,258 TORP2 TORP3 FLS2 Heavyweight torpedo (e.g., MK 48) ................ Heavyweight torpedo test (e.g., MK 48) ......... HF sources with short pulse lengths, narrow beam widths, and focused beam patterns. C C H 332–372 6 24 2,324 42 168 M3 MF acoustic modems (greater than 190 dB) .. H 1,088 7,616 SAS2 HF SAS systems ............................................. H 1,312 9,184 BB1 MF to HF mine countermeasure sonar ........... H 48 336 BB2 HF to VHF mine countermeasure sonar ......... H 48 336 Notes: H = hours; C = count. Table 7 describes the explosive source classes and numbers that could occur over seven years under the proposed training activities. Under the proposed activities bin use would vary annually, and the seven-year totals for the proposed training activities take into account that annual variability. TABLE 7—EXPLOSIVE SOURCE CLASS BINS ANALYZED AND NUMBERS USED FOR SEVEN-YEAR PERIOD FOR TRAINING ACTIVITIES IN THE NWTT STUDY AREA Bin E1 ........................................... E2 ........................................... E3 ........................................... E5 ........................................... E10 ......................................... Net explosive weight (lb) 0.1–0.25 >0.25–0.5 >0.5–2.5 >5–10 >250–500 Example explosive source Annual Medium-caliber projectiles ...................................................... Medium-caliber projectiles ...................................................... Explosive Ordnance Disposal Mine Neutralization ................. Large-caliber projectile ............................................................ 1,000 lb bomb ......................................................................... 7-Year total 60–120 65–130 6 56–112 0–4 672 728 42 628 9 Notes: (1) Net explosive weight refers to the equivalent amount of TNT. The actual weight of a munition may be larger due to other components. lb = pound(s), ft = feet. Table 8 describes the explosive source classes and numbers that could occur over seven years under the proposed testing activities. Under the proposed activities bin use would vary annually, and the seven-year totals for the proposed testing activities take into account that annual variability. TABLE 8—EXPLOSIVE SOURCE CLASS BINS ANALYZED AND NUMBERS USED FOR SEVEN-YEAR PERIOD FOR TESTING ACTIVITIES IN THE NWTT STUDY AREA khammond on DSKJM1Z7X2PROD with PROPOSALS2 Bin E1 ........................................... E3 ........................................... E4 ........................................... E7 ........................................... E8 ........................................... E11 ......................................... Net explosive weight (lb) 0.1–0.25 >0.5–2.5 >2.5–5 >20–60 >60–100 >500–650 Example explosive source Annual SUS buoy ................................................................................ Explosive sonobuoy ................................................................ Mine Countermeasure and Neutralization .............................. Mine Countermeasure and Neutralization .............................. Lightweight torpedo ................................................................ Heavyweight torpedo .............................................................. 7-Year total 8 72 36 5 4 4 56 504 180 25 28 28 Notes: (1) Net explosive weight refers to the equivalent amount of TNT. The actual weight of a munition may be larger due to other components. lb = pound(s), ft = feet. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00016 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Vessel Movement Vessels used as part of the proposed activities include ships, submarines, unmanned vessels, and boats ranging in size from small, 22 ft rigid hull inflatable boats to aircraft carriers with lengths up to 1,092 ft. Large ships greater than 60 ft generally operate at speeds in the range of 10–15 kn for fuel conservation. Submarines generally operate at speeds in the range of 8–13 kn in transits and less than those speeds for certain tactical maneuvers. Small craft (for purposes of this discussion— less than 60 ft in length) have much more variable speeds (dependent on the mission). While these speeds are representative of most events, some vessels need to temporarily operate outside of these parameters. For example, to produce the required relative wind speed over the flight deck, an aircraft carrier engaged in flight operations must adjust its speed through the water accordingly. Conversely, there are other instances, such as launch and recovery of a small rigid hull inflatable boat; vessel boarding, search, and seizure training events; or retrieval of a target when vessels will be dead in the water or moving slowly ahead to maintain steerage. The number of military vessels used in the NWTT Study Area varies based on military training and testing requirements, deployment schedules, annual budgets, and other unpredictable factors. Many training and testing activities involve the use of vessels. These activities could be widely dispersed throughout the NWTT Study Area, but would be typically conducted near naval ports, piers, and range areas. Training and testing activities involving vessel movements occur intermittently and are variable in duration, ranging from a few hours to up to two weeks. There is no seasonal differentiation in military vessel use. Large vessel movement primarily occurs with the majority of the traffic flowing between the installations and the Operating Areas (OPAREAS). Smaller support craft would be more concentrated in the coastal waters in the areas of naval installations, ports, and ranges. The number of activities that include the use of vessels for training events is lower (approximately 10 percent) than the number for testing activities. Testing can occur jointly with a training event, in which case that testing activity could be conducted from a training vessel. Additionally, a variety of smaller craft will be operated within the NWTT Study Area. Small craft types, sizes, and speeds vary. During training and testing, speeds generally range from 10–14 kn; VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 however, vessels can and will, on occasion, operate within the entire spectrum of their specific operational capabilities. In all cases, the vessels/ craft will be operated in a safe manner consistent with the local conditions. Standard Operating Procedures For training and testing to be effective, personnel must be able to safely use their sensors and weapon systems as they are intended to be used in military missions and combat operations and to their optimum capabilities. While standard operating procedures are designed for the safety of personnel and equipment and to ensure the success of training and testing activities, their implementation often yields benefits to environmental, socioeconomic, public health and safety, and cultural resources. Navy standard operating procedures have been developed and refined over years of experience and are broadcast via numerous naval instructions and manuals, including, but not limited to the following materials: • Ship, submarine, and aircraft safety manuals; • Ship, submarine, and aircraft standard operating manuals; • Fleet Area Control and Surveillance Facility range operating instructions; • Fleet exercise publications and instructions; • Naval Sea Systems Command test range safety and standard operating instructions; • Navy-instrumented range operating procedures; • Naval shipyard sea trial agendas; • Research, development, test, and evaluation plans; • Naval gunfire safety instructions; • Navy planned maintenance system instructions and requirements; • Federal Aviation Administration regulations; and • International Regulations for Preventing Collisions at Sea. Because standard operating procedures are essential to safety and mission success, the Navy considers them to be part of the proposed Specified Activities, and has included them in the environmental analysis. Standard operating procedures that are recognized as having a potential benefit to marine mammals during training and testing activities are noted below and discussed in more detail within the 2019 NWTT DSEIS/OEIS. • Vessel Safety; • Weapons Firing Procedures; • Target Deployment Safety; and • Towed In-Water Device Safety. Standard operating procedures (which are implemented regardless of their PO 00000 Frm 00017 Fmt 4701 Sfmt 4702 33929 secondary benefits) are different from mitigation measures (which are designed entirely for the purpose of avoiding or reducing environmental impacts). Information on mitigation measures is provided in the Proposed Mitigation section below. Additional information on standard operating procedures is presented in Section 2.3.3 (Standard Operating Procedures) in the 2019 NWTT DSEIS/OEIS. Description of Marine Mammals and Their Habitat in the Area of the Specified Activities Marine mammal species and their associated stocks that have the potential to occur in the NWTT Study Area are presented in Table 9 along with an abundance estimate, an associated coefficient of variation value, and best and minimum abundance estimates. The Navy requests authorization to take individuals of 29 marine mammal species by Level A harassment and Level B harassment incidental to training and testing activities from the use of sonar and other transducers and in-water detonations. In addition, the Navy requests authorization for three takes of large whales by serious injury or mortality from vessel strikes over the seven-year period. Currently, the Southern Resident killer whale has critical habitat designated under the Endangered Species Act (ESA) in the NWTT Study Area (described below). However, NMFS has recently published two proposed rules, proposing new or revised ESA-designated critical habitat for humpback whales (84 FR 54354; October 9, 2019) and Southern Resident killer whales (84 FR 49214; September 19, 2019). Information on the status, distribution, abundance, population trends, habitat, and ecology of marine mammals in the NWTT Study Area may be found in Chapter 4 of the Navy’s rulemaking/LOA application. NMFS has reviewed this information and found it to be accurate and complete. Additional information on the general biology and ecology of marine mammals is included in the 2019 NWTT DSEIS/OEIS. Table 9 incorporates data from the U.S. Pacific and the Alaska Marine Mammal Stock Assessment Reports (SARs; Carretta et al., 2019; Muto et al., 2019) and the most recent revised data in the draft SARs (see https://www.fisheries.noaa .gov/national/marine-mammalprotection/draft-marine-mammal-stockassessment-reports); as well as incorporates the best available science, including monitoring data from the Navy’s marine mammal research efforts. E:\FR\FM\02JNP2.SGM 02JNP2 33930 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Species Not Included in the Analysis The species carried forward for analysis (and described in Table 9 below) are those likely to be found in the NWTT Study Area based on the most recent data available, and do not include species that may have once inhabited or transited the area but have not been sighted in recent years (e.g., species which were extirpated from factors such as 19th and 20th century commercial exploitation). Several species that may be present in the northwest Pacific Ocean have an extremely low probability of presence in the NWTT Study Area. These species are considered extralimital (not anticipated to occur in the Study Area) or rare (occur in the Study Area sporadically, but sightings are rare). These species/stocks include the Eastern North Pacific stock of Bryde’s whale (Balaenoptera edeni), Eastern North Pacific stock of North Pacific right whale (Eubalaena japonica), false killer whale (Pseudorca crassidens), longbeaked common dolphin (Delphinus capensis), Western U.S. stock of Steller sea lion (Eumetopias jubatus), and Alaska stock of Cuvier’s beaked whale (Ziphius cavirostris). Despite rare stranding or sighting reports, the Study Area is outside the normal range of the Eastern North Pacific stock of Bryde’s whale and the California stock of the long-beaked common dolphin. The Study Area is also outside the normal range of the false killer whale’s distribution in the Pacific Ocean. The Eastern North Pacific stock of North Pacific right whale is estimated to have an abundance of 31 individuals (Muto et al., 2020) and is anticipated to be extremely rare in the Study Area. The Western U.S. stock of Steller sea lions is considered rare in the Offshore Area of the Study Area, and is not expected to occur in the Inland Waters portion of the Study Area. In Western Behm Canal, there is a low probability of juvenile male Steller sea lion occurrence from the Western U.S. stock, however these individuals are anticipated to be very rare. Finally, the Alaska stock of Cuvier’s beaked whales is not expected to occur in either the Offshore Area or Inland Waters of the NWTT Study Area, and are considered extralimital in Western Behm Canal as this area does not overlap with their range of distribution. NMFS agrees with the Navy’s assessment that these species are unlikely to occur in the NWTT Study Area and they are not discussed further. TABLE 9—MARINE MAMMAL OCCURRENCE WITHIN THE NWTT STUDY AREA Common name Scientific name ESA/ MMPA status; strategic (Y/N) 1 Stock Stock abundance (CV, Nmin, most recent abundance survey) 2 Occurrence PBR Annual M/SI 3 Offshore area Inland waters Seasonal .... Seasonal .... Western Behm Canal Order Cetartiodactyla—Cetacea—Superfamily Mysticeti (baleen whales) Family Eschrichtiidae: Gray whale ................... Eschrichtius robustus ........ Eastern North Pacific ........ -, -, N 26.960 (0.05, 25,849, 2016). 801 139 Family Balaenopteridae (rorquals): Blue whale ................... Fin whale ..................... Balaenoptera musculus ..... Balaenoptera physalus ...... Humpback whale ......... Megaptera novaeangliae ... Eastern North Pacific ........ Northeast Pacific ............... CA/OR/WA ........................ Central North Pacific ......... 1,496 (0.44, 3,168 (0.26, 9,029 (0.12, 10,103 (0.3, 1.2 5.1 81 83 ≥19.4 0.4 ≥43.5 25 Seasonal .... Regular ...... Rare ........... Regular ...... 2,900 (0.05, 2,784, 2014) 16.7 ≥42.1 Regular ...... Regular ...... Minke whale ................. Balaenoptera acutorostrata Sei whale ..................... Balaenoptera borealis ....... E, D, S E, D, S E, D, S T/E,5 D, S T/E,5 D, S -, -, N -, -, N E, D, S UNK ................................... 636 (0.72, 369, 2014) ....... 519 (0.4, 374, 2014) ......... UND 3.5 0.75 0 ≥1.3 ≥0.2 2.5 0.4 CA/OR/WA ........................ Alaska ................................ CA/OR/WA ........................ Eastern North Pacific ........ 1,050, 2,554, 8,127, 7,891, 2014) 2013) 4 2014) 2006) Seasonal. Rare. Regular. Regular. Rare. Regular ...... Regular ...... Seasonal. .................... Superfamily Odontoceti (toothed whales, dolphins, and porpoises) khammond on DSKJM1Z7X2PROD with PROPOSALS2 Family Physeteridae: Sperm whale ................ Family Kogiidae: Dwarf sperm whale ...... Pygmy sperm whale .... Family Ziphiidae (beaked whales): Baird’s beaked whale .. Cuvier’s beaked whale Mesoplodont beaked whales. Family Delphinidae: Common bottlenose dolphin. Killer whale .................. Physeter macrocephalus ... CA/OR/WA ........................ E, D, S 1.997 (0.57, 1,270, 2014) Kogia sima ........................ Kogia breviceps ................. CA/OR/WA ........................ CA/OR/WA ........................ -, -, N -, -, N UNK ................................... 4,111 (1.12, 1,924, 2014) UND 19.2 0 0 Rare. Regular. Berardius bairdii ................ Ziphius cavirostris ............. Mesoplodon species ......... CA/OR/WA ........................ CA/OR/WA ........................ CA/OR/WA ........................ -, -, N -, -, N -, -, N 2,697 (0.6, 1,633, 2014) ... 3,274 (0.67, 2,059, 2014) 3,044 (0.54, 1,967, 2014) 16 21 20 0 < 0.1 0.1 Regular. Regular. Regular. Tursiops truncatus ............. CA/OR/WA Offshore ......... -, -, N 1,924 (0.54, 1,255, 2014) 11 ≥1.6 Regular. Orcinus orca ...................... Eastern North Pacific Alaskan Resident. Eastern North Pacific Northern Resident. West Coast Transient ....... Eastern North Pacific Offshore. Eastern North Pacific Southern Resident. CA/OR/WA ........................ -, -, N 2,347 (UNK, 2,347, 24 1 -, -, N 302 (UNK, 302, 2018) 6 ..... 2.2 0.2 Seasonal .... Seasonal .... -, -, N -, -, N 243 (UNK, 243, 2009) ....... 300 (0.1, 276, 2012) ......... 2.4 2.8 0 0 Regular ...... Regular ...... Regular ...... E, D, Y 75 (NA, 75, 2018) ............. 0.13 0 Seasonal .... Regular ...... -, -, N 3.8 -, -, N 26,556 (0.44, 18,608, 2014). 26,880 (UNK, NA, 1990) ... 179 North Pacific ...................... UND 0 Northern right whale dolphin. Pacific white-sided dolphin. Lissodelphus borealis ........ CA/OR/WA ........................ -, -, N Risso’s dolphin ............. Short-beaked common dolphin. Short-finned pilot whale Grampus griseus ............... Delphinus delphis .............. CA/OR/WA ........................ CA/OR/WA ........................ -, -, N -, -, N Globicephala macrorhynchus. Stenella coeruleoalba ........ CA/OR/WA ........................ Phocoenoides dalli ............ Striped dolphin ............. Family Phocoenidae (porpoises): Dall’s porpoise ............. VerDate Sep<11>2014 Lagenorhynchus obliquidens. 21:30 Jun 01, 2020 Jkt 250001 2012) 6 Rare. Regular. Regular. Regular. 191 7.5 Regular ...... Regular ...... 46 8,393 ≥3.7 e40 Regular ...... Regular ...... Rare ........... Rare ........... -, -, N 26,814 (0.28, 21,195, 2014). 6,336 (0.32, 4,817, 2014) 969,861 (0.17, 839,325, 2014). 836 (0.79, 466, 2014) ....... 4.5 1.2 Regular ...... Rare ........... CA/OR/WA ........................ -, -, N 29,211 (0.2, 24,782, 2014) 238 ≥0.8 Alaska ................................ -, -, N 83,400 (0.097, NA, 1991) UND 38 PO 00000 Frm 00018 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Regular. Regular. Regular. Regular. 33931 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 9—MARINE MAMMAL OCCURRENCE WITHIN THE NWTT STUDY AREA—Continued Common name Harbor porpoise ........... Scientific name Phocoena phocoena ......... ESA/ MMPA status; strategic (Y/N) 1 Stock CA/OR/WA ........................ -, -, N Southeast Alaska .............. Northern OR/WA Coast .... -, -, Y -, -, N Northern CA/Southern OR -, -, N Washington Inland Waters -, -, N Stock abundance (CV, Nmin, most recent abundance survey) 2 25,750 (0.45, 17,954, 2014). 1,354 (0.12, 1,224, 2012) 21,487 (0.44, 15, 123, 2011). 35,769 (0.52, 23,749, 2011). 11,233 (0.37, 8,308, 2015) Occurrence PBR Annual M/SI 3 Offshore area Inland waters Regular ...... 172 0.3 Regular ...... 12 151 34 ≥3 Regular. 475 ≥0.6 Regular. 66 ≥7.2 14,011 ≥321 Seasonal .... 1,062 11,295 ≥3.8 399 Seasonal. Regular ...... 451 2,592 1.8 113 Regular. Regular ...... 746 40 UND 1,641 10.6 43 Regular ...... Regular. Seasonal .... UND 9.8 Seasonal .... Regular ...... UND UND 4,882 0.2 3.4 8.8 Seasonal .... Seasonal .... Regular ...... Regular ...... Regular ...... Regular ...... Western Behm Canal Regular. Regular ...... Order Carnivora—Superfamily Pinnipedia Family Otariidae (eared seals and sea lions): California sea lion ........ Zalophus californianus ...... U.S. ................................... -, -, N Guadalupe fur seal ...... Northern fur seal .......... Arctocephalus townsendi .. Callorhinus ursinus ............ Mexico to California .......... Eastern Pacific .................. T, D, Y -, D, Y Steller sea lion ............. Eumetopias jubatus ........... California ........................... Eastern U.S. ...................... -, -, N -, -, N Family Phocidae (earless seals): Harbor seal .................. Phoca vitulina .................... Southeast Alaska (Clarence Strait). OR/WA Coast .................... California ........................... -, -, N Washington Northern Inland Waters. Hood Canal ....................... Southern Puget Sound ...... California ........................... -, -, N Northern Elephant seal Mirounga angustirostris ..... -, -, N -, -, N -, -, N -, -, N -, -, N 257,606 (NA, 233,515, 2014). 34,187 (NA, 31,109, 2013) 620,660 (0.2, 525,333, 2016). 14,050 (NA, 7,524, 2013) 43,201 (NA, 43,201, 2017) 7. 27,659 (UNK, 24,854, 2015). UNK ................................... 30,968 (0.157, 27,348, 2012). UNK ................................... UNK ................................... UNK ................................... 179,000 (NA, 81,368, 2010). Regular ...... Seasonal. Seasonal .... Regular. Regular. Seasonal. 1 Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds potential biological removal (PBR) or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is automatically designated under the MMPA as depleted and as a strategic stock. 2 NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For the Eastern North Pacific Southern Resident stock of killer whales Nbest/Nmin are based on a direct count of individually identifiable animals. The population size of the U.S. stock of California sea lion was estimated from a 1975–2014 time series of pup counts (Lowry et al. 2017), combined with mark-recapture estimates of survival rates (DeLong et al. 2017, Laake et al. 2018). The population size of the Mexico to California stock of Guadalupe fur seals was estimated from pup count data collected in 2013 and a range of correction factors applied to pup counts to account for uncounted age classes and pre-census pup mortality (Garcı´a-Aguilar et al. 2018). The population size of the California stock of Northern fur seals was estimated from pup counts multiplied by an expansion factor (San Miguel Island) and maximum pup, juvenile, and adult counts (Farrallon Islands) at rookeries. The population size of the Eastern U.S. stock of Steller sea lions was estimated from pup counts and non-pup counts at rookeries in Southeast Alaska, British Columbia, Oregon, and California. The population size of the California stock of Northern Elephant seals was estimated from pup counts at rookeries multiplied by the inverse of the expected ratio of pups to total animals (McCann, 1985; Lowry et al., 2014). 3 These values, found in NMFS’ SARs, represent annual levels of human-caused mortality and serious injury (M/SI) from all sources combined (e.g., commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated with estimated mortality due to commercial fisheries is presented in some cases. 4 SAR reports this stock abundance assessment as provisional and notes that it is an underestimate for the entire stock because it is based on surveys which covered only a small portion of the stock’s range. 5 Humpback whales in the Central North Pacific stock and the CA/OR/WA stock are from three Distinct Population Segments (DPSs) based on animals identified in breeding areas in Hawaii, Mexico, and Central America. Both stocks and all three DPSs co-occur in the NWTT Study Area. 6 Stock abundance estimate is based on counts of individual animals identified from photo-identification catalogues. Surveys for abundance estimates of these stocks are conducted infrequently. 7 Stock abundance estimate is the best estimate counts, which have not been corrected to account for animals at sea during abundance surveys. Note—Unknown (UNK); Undetermined (UND); Not Applicable (NA); California (CA); Oregon (OR); Washington (WA). Below, we include additional information about the marine mammals in the area of the Specified Activities that informs our analysis, such as identifying known areas of important habitat or behaviors, or where Unusual Mortality Events (UME) have been designated. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Critical Habitat Currently, only the distinct population segment (DPS) of Southern Resident killer whale (SRKW) has ESAdesignated critical habitat in the NWTT Study Area. NMFS has recently published two proposed rules, however, proposing new or revised ESAdesignated critical habitat for SRKW (84 FR 49214; September 19, 2019) and humpback whales (84 FR 54354; October 9, 2019). VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 NMFS designated critical habitat for the SRKW DPS on November 29, 2006 (71 FR 69054) in inland waters of Washington State. Based on the natural history of the SRKWs and their habitat needs, NMFS identified physical or biological features essential to the conservation of the SRKW DPS: (1) Water quality to support growth and development; (2) prey species of sufficient quantity, quality, and availability to support individual growth, reproduction and development, as well as overall population growth; and (3) passage conditions to allow for migration, resting, and foraging. ESAdesignated critical habitat consists of three areas: (1) The Summer Core Area in Haro Strait and waters around the San Juan Islands; (2) Puget Sound; and (3) the Strait of Juan de Fuca, which comprise approximately 2,560 square PO 00000 Frm 00019 Fmt 4701 Sfmt 4702 miles (mi2) (6,630 square kilometers (km2)) of marine habitat. In designating critical habitat, NMFS considered economic impacts and impacts to national security, and concluded the benefits of exclusion of 18 military sites, comprising approximately 112 mi2 (291 km2), outweighed the benefits of inclusion because of national security impacts. On January 21, 2014, NMFS received a petition requesting revisions to the SRKW critical habitat designation. The petition requested NMFS revise critical habitat to include ‘‘inhabited marine waters along the West Coast of the United States that constitute essential foraging and wintering areas,’’ specifically the region between Cape Flattery, Washington and Point Reyes, California extending from the coast to a distance of 47.2 mi (76 km) offshore. E:\FR\FM\02JNP2.SGM 02JNP2 33932 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 The petition also requested NMFS adopt a fourth essential habitat feature in both current and expanded critical habitat relating to in-water sound levels. On September 19, 2019 (84 FR 54354), NMFS published a proposed rule proposing to revise the critical habitat designation for the SRKW DPS by designating six new areas (using the same essential features determined in 2006) along the U.S. West Coast. Specific new areas proposed along the U.S. West Coast include 15,626.6 mi2 (40,472.7 km2) of marine waters between the 6.1 m (20 ft) depth contour and the 200 m (656.2 ft) depth contour from the U.S. international border with Canada south to Point Sur, California. On March 15, 2018, several nongovernmental organizations filed a lawsuit seeking court-ordered deadlines for the issuance of proposed and final rules to designate ESA critical habitat for the Central American, Mexico, and Western North Pacific DPSs of humpback whales. In 2018, NMFS convened a critical habitat review team to assess and evaluate information in support of critical habitat designation for these DPSs. On October 9, 2019 (84 FR 54354), NMFS published a proposed rule proposing ESA-designated critical habitat areas located off the coasts of California, Oregon, Washington, and Alaska, including areas within the NWTT Study Area. Based on consideration of national security and economic impacts, NMFS also proposed to exclude multiple areas from the designation for each DPS. Biologically Important Areas Biologically Important Areas (BIAs) include areas of known importance for reproduction, feeding, or migration, or areas where small and resident populations are known to occur (Van Parijs, 2015). Unlike ESA critical habitat, these areas are not formally designated pursuant to any statute or law, but are a compilation of the best available science intended to inform impact and mitigation analyses. An interactive map of the BIAs may be found here: https://cetsound.noaa.gov/ biologically-important-area-map. BIAs off the West Coast of the continental United States with the potential to overlap portions of the NWTT Study Area include the following feeding and migration areas: Northern Puget Sound Feeding Area for gray whales (March–May); Northwest Feeding Area for gray whales (May– November); Northbound Migration Phase A for gray whales (January–July); Northbound Migration Phase B for gray whales (March–July); Northern Washington Feeding Area for humpback VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 whales (May–November); Stonewall and Heceta Bank Feeding Area for humpback whales (May–November); and Point St. George Feeding Area for humpback whales (July–November) (Calambokidis et al., 2015). When comparing the geographic area of the NWTT Study Area with the BIAs off the West Coast of the continental United States, there is no direct spatial overlap between the Study Area and four of the offshore gray whale feeding areas—Grays Harbor, WA; Depoe Bay, OR; Cape Blanco and Orford Reef, OR; and Pt. St. George, CA. The NWTT Study Area does overlap with the Northwest WA gray whale feeding area and the Northern Puget Sound gray whale feeding area. There is no overlap of the gray whale migration corridor BIAs and the NWTT Study Area, with the exception of a portion of the Northwest coast of Washington approximately from Pacific Beach and extending north to the Strait of Juan de Fuca. The offshore Northern WA humpback whale feeding area is located entirely within the NWTT Study Area boundaries. The humpback whale feeding area at Stonewall and Hecta Bank only partially overlaps with the Study Area, and the feeding area at Point St. George has extremely limited overlap with the Study Area. All proposed activities occurring in the Offshore Area of the Study Area could potentially occur in these BIAs, except activities limited to greater than 50 nmi from shore (as described in the Proposed Mitigation Measures section). To mitigate impacts to marine mammals in these BIAs, the Navy would implement several procedural mitigation measures and mitigation areas (described in the Proposed Mitigation Measures section). National Marine Sanctuaries Under Title III of the Marine Protection, Research, and Sanctuaries Act of 1972 (also known as the National Marine Sanctuaries Act (NMSA)), NOAA can establish as national marine sanctuaries (NMS), areas of the marine environment with special conservation, recreational, ecological, historical, cultural, archaeological, scientific, educational, or aesthetic qualities. Sanctuary regulations prohibit or regulate activities that could destroy, cause the loss of, or injure sanctuary resources pursuant to the regulations for that sanctuary and other applicable law (15 CFR part 922). NMSs are managed on a site-specific basis, and each sanctuary has site-specific regulations. Most, but not all, sanctuaries have sitespecific regulatory exemptions from the prohibitions for certain military PO 00000 Frm 00020 Fmt 4701 Sfmt 4702 activities. Separately, section 304(d) of the NMSA requires Federal agencies to consult with the Office of National Marine Sanctuaries whenever their activities are likely to destroy, cause the loss of, or injure a sanctuary resource. One NMS, the Olympic Coast NMS managed by the Office of National Marine Sanctuaries, is located within the offshore portion of the NWTT Study Area (for a map of the location of this NMS see Chapter 6 of the 2019 NWTT DSEIS/OEIS and Figure 6–1). The Olympic Coast NMS includes 3,188 mi2 of marine waters and submerged lands off the Olympic Peninsula coastline. The sanctuary extends 25–50 mi. (40.2–80.5 km) seaward, covering much of the continental shelf and portions of three major submarine canyons. The boundaries of the sanctuary as defined in the Olympic Coast NMS regulations (15 CFR part 922, subpart O) extend from Koitlah Point, due north to the United States/Canada international boundary, and seaward to the 100fathom isobath (approximately 180 m in depth). The seaward boundary of the sanctuary follows the 100-fathom isobath south to a point due west of Copalis River, and cuts across the tops of Nitinat, Juan de Fuca, and the Quinault Canyons. The shoreward boundary of the sanctuary is at the mean lower low-water line when adjacent to American Indian lands and state lands, and includes the intertidal areas to the mean higher high-water line when adjacent to federally managed lands. When adjacent to rivers and streams, the sanctuary boundary cuts across the mouths but does not extend up river or up stream. The Olympic Coast NMS includes many types of productive marine habitats including kelp forests, subtidal reefs, rocky and sand intertidal zones, submarine canyons, rocky deepsea habitat, and plankton-rich upwelling zones. These habitats support the Sanctuary’s rich biodiversity which includes 29 species of marine mammals that reside in or migrate through the Sanctuary (Office of National Marine Sanctuaries 2008). Additional information on the Olympic Coast NMS can be found at https:// olympiccoast.noaa.gov. Unusual Mortality Events (UMEs) An UME is defined under Section 410(6) of the MMPA as a stranding that is unexpected; involves a significant die-off of any marine mammal population; and demands immediate response. Three UMEs with ongoing investigations in the NWTT Study Area that inform our analysis are discussed below. The California sea lion UME in E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 California is still open, but will be closed soon. The Guadalupe fur seal UME in California and the gray whale UME along the west coast of North America are active and involve ongoing investigations. California Sea Lion UME From January 2013 through September 2016, a greater than expected number of young malnourished California sea lions (Zalophus californianus) stranded along the coast of California. Sea lions stranding from an early age (6–8 months old) through two years of age (hereafter referred to as juveniles) were consistently underweight without other disease processes detected. Of the 8,122 stranded juveniles attributed to the UME, 93 percent stranded alive (n = 7,587, with 3,418 of these released after rehabilitation) and 7 percent (n = 531) stranded dead. Several factors are hypothesized to have impacted the ability of nursing females and young sea lions to acquire adequate nutrition for successful pup rearing and juvenile growth. In late 2012, decreased anchovy and sardine recruitment (CalCOFI data, July 2013) may have led to nutritionally stressed adult females. Biotoxins were present at various times throughout the UME, and while they were not detected in the stranded juvenile sea lions (whose stomachs were empty at the time of stranding), biotoxins may have impacted the adult females’ ability to support their dependent pups by affecting their cognitive function (e.g., navigation, behavior towards their offspring). Therefore, the role of biotoxins in this UME, via its possible impact on adult females’ ability to support their pups, is unclear. The proposed primary cause of the UME was malnutrition of sea lion pups and yearlings due to ecological factors. These factors included shifts in distribution, abundance and/or quality of sea lion prey items around the Channel Island rookeries during critical sea lion life history events (nursing by adult females, and transitioning from milk to prey by young sea lions). These prey shifts were most likely driven by unusual oceanographic conditions at the time due to the ‘‘Warm Water Blob’’ and El Nin˜o. This investigation will soon be closed. Please refer to: https:// www.fisheries.noaa.gov/national/ marine-life-distress/2013-2017california-sea-lion-unusual-mortalityevent-california for more information on this UME. Guadalupe Fur Seal UME Increased strandings of Guadalupe fur seals began along the entire coast of VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 California in January 2015 and were eight times higher than the historical average (approximately 10 seals/yr). Strandings have continued since 2015 and remained well above average through 2019. Numbers by year are as follows: 2015 (98), 2016 (76), 2017 (62), 2018 (45), 2019 (116), 2020 (3 as of March 6, 2020). The total number of Guadalupe fur seals stranding in California from January 1, 2015, through March 6, 2020, in the UME is 400. Additionally, strandings of Guadalupe fur seals became elevated in the spring of 2019 in Washington and Oregon; subsequently, strandings for seals in these two states have been added to the UME starting from January 1, 2019. The current total number of strandings in Washington and Oregon is 94 seals, including 91 in 2019 and 3 in 2020 of 3/6/2020. Strandings are seasonal and generally peak in April through June of each year. The Guadalupe fur seal strandings have been mostly weaned pups and juveniles (1–2 years old) with both live and dead strandings occurring. Current findings from the majority of stranded animals include primary malnutrition with secondary bacterial and parasitic infections. The California portion of this UME was occurring in the same area as the 2013–2016 California sea lion UME. This investigation is ongoing. Please refer to: https://www.fisheries.noaa.gov/ national/marine-life-distress/2015-2019guadalupe-fur-seal-unusual-mortalityevent-california for more information on this UME. Gray Whale UME Since January 1, 2019, elevated gray whale strandings have occurred along the west coast of North America, from Mexico to Canada. As of March 13, 2020, there have been a total of 264 strandings along the coasts of the United States, Canada, and Mexico, with 129 of those strandings occurring along the U.S. coast. Of the strandings on the U.S. coast, 48 have occurred in Alaska, 35 in Washington, 6 in Oregon, and 40 in California. Partial necropsy examinations conducted on a subset of stranded whales have shown evidence of poor to thin body condition. As part of the UME investigation process, NOAA is assembling an independent team of scientists to coordinate with the Working Group on Marine Mammal Unusual Mortality Events to review the data collected, sample stranded whales, and determine the next steps for the investigation. Please refer to: https:// www.fisheries.noaa.gov/national/ marine-life-distress/2019-gray-whaleunusual-mortality-event-along-westcoast for more information on this UME. PO 00000 Frm 00021 Fmt 4701 Sfmt 4702 33933 Marine Mammal Hearing Hearing is the most important sensory modality for marine mammals underwater, and exposure to anthropogenic sound can have deleterious effects. To appropriately assess the potential effects of exposure to sound, it is necessary to understand the frequency ranges marine mammals are able to hear. Current data indicate that not all marine mammal species have equal hearing capabilities (e.g., Richardson et al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect this, Southall et al. (2007) recommended that marine mammals be divided into functional hearing groups based on directly measured or estimated hearing ranges on the basis of available behavioral response data, audiograms derived using auditory evoked potential techniques, anatomical modeling, and other data. Note that no direct measurements of hearing ability have been successfully completed for mysticetes (i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described generalized hearing ranges for these marine mammal hearing groups. Generalized hearing ranges were chosen based on the approximately 65 dB threshold from the normalized composite audiograms, with the exception for lower limits for lowfrequency cetaceans where the lower bound was deemed to be biologically implausible and the lower bound from Southall et al. (2007) retained. The functional groups and the associated frequencies are indicated below (note that these frequency ranges correspond to the range for the composite group, with the entire range not necessarily reflecting the capabilities of every species within that group): • Low-frequency cetaceans (mysticetes): Generalized hearing is estimated to occur between approximately 7 Hz and 35 kHz; • Mid-frequency cetaceans (larger toothed whales, beaked whales, and most delphinids): Generalized hearing is estimated to occur between approximately 150 Hz and 160 kHz; • High-frequency cetaceans (porpoises, river dolphins, and members of the genera Kogia and Cephalorhynchus; including two members of the genus Lagenorhynchus, on the basis of recent echolocation data and genetic data): Generalized hearing is estimated to occur between approximately 275 Hz and 160 kHz; • Pinnipeds in water; Phocidae (true seals): Generalized hearing is estimated to occur between approximately 50 Hz to 86 kHz; and E:\FR\FM\02JNP2.SGM 02JNP2 33934 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 • Pinnipeds in water; Otariidae (eared seals): Generalized hearing is estimated to occur between 60 Hz and 39 kHz. The pinniped functional hearing group was modified from Southall et al. (2007) on the basis of data indicating that phocid species have consistently demonstrated an extended frequency range of hearing compared to otariids, especially in the higher frequency range (Hemila¨ et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 2013). For more details concerning these groups and associated frequency ranges, please see NMFS (2018) for a review of the available information. Potential Effects of Specified Activities on Marine Mammals and Their Habitat This section includes a discussion of the ways that components of the specified activity may impact marine mammals and their habitat. The Estimated Take of Marine Mammals section later in this rule includes a quantitative analysis of the number of instances of take that could occur from these activities. The Preliminary Analysis and Negligible Impact Determination section considers the content of this section, the Estimated Take of Marine Mammals section, and the Proposed Mitigation Measures section to draw conclusions regarding the likely impacts of these activities on the reproductive success or survivorship of individuals and whether those impacts on individuals are likely to adversely affect the species through effects on annual rates of recruitment or survival. The Navy has requested authorization for the take of marine mammals that may occur incidental to training and testing activities in the NWTT Study Area. The Navy analyzed potential impacts to marine mammals from acoustic and explosive sources and from vessel use in its rulemaking/LOA application. NMFS carefully reviewed the information provided by the Navy along with independently reviewing applicable scientific research and literature and other information to evaluate the potential effects of the Navy’s activities on marine mammals, which are presented in this section. Other potential impacts to marine mammals from training and testing activities in the NWTT Study Area were analyzed in the 2019 NWTT DSEIS/ OEIS, in consultation with NMFS as a cooperating agency, and determined to be unlikely to result in marine mammal take. This includes serious injury or mortality from explosives. Therefore, the Navy has not requested authorization for take of marine mammals incidental to other VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 components of their proposed Specified Activities, and we agree that incidental take is unlikely to occur from those components. In this proposed rule, NMFS analyzes the potential effects on marine mammals from the activity components that may cause the take of marine mammals: Exposure to acoustic or explosive stressors including nonimpulsive (sonar and other transducers) and impulsive (explosives) stressors and vessel movement. For the purpose of MMPA incidental take authorizations, NMFS’ effects assessments serve four primary purposes: (1) To determine whether the specified activities would have a negligible impact on the affected species or stocks of marine mammals (based on whether it is likely that the activities would adversely affect the species or stocks through effects on annual rates of recruitment or survival); (2) to determine whether the specified activities would have an unmitigable adverse impact on the availability of the species or stocks for subsistence uses; (3) to prescribe the permissible methods of taking (i.e., Level B harassment (behavioral harassment and temporary threshold shift (TTS)), Level A harassment (permanent threshold shift (PTS) and non-auditory injury), serious injury, or mortality), including identification of the number and types of take that could occur by harassment, serious injury, or mortality, and to prescribe other means of effecting the least practicable adverse impact on the species or stocks and their habitat (i.e., mitigation measures); and (4) to prescribe requirements pertaining to monitoring and reporting. In this section, NMFS provides a description of the ways marine mammals may be generally affected by these activities in the form of mortality, physical trauma, sensory impairment (permanent and temporary threshold shifts and acoustic masking), physiological responses (particular stress responses), behavioral disturbance, or habitat effects. Explosives and vessel strikes, which have the potential to result in incidental take from serious injury and/or mortality, will be discussed in more detail in the Estimated Take of Marine Mammals section. The Estimated Take of Marine Mammals section also discusses how the potential effects on marine mammals from non-impulsive and impulsive sources relate to the MMPA definitions of Level A Harassment and Level B Harassment, and quantifies those effects that rise to the level of a take. The Preliminary Analysis and Negligible Impact Determination section assesses whether PO 00000 Frm 00022 Fmt 4701 Sfmt 4702 the proposed authorized take would have a negligible impact on the affected species and stocks. Potential Effects of Underwater Sound Anthropogenic sounds cover a broad range of frequencies and sound levels and can have a range of highly variable impacts on marine life, from none or minor to potentially severe responses, depending on received levels, duration of exposure, behavioral context, and various other factors. The potential effects of underwater sound from active acoustic sources can possibly result in one or more of the following: Temporary or permanent hearing impairment, nonauditory physical or physiological effects, behavioral disturbance, stress, and masking (Richardson et al., 1995; Gordon et al., 2004; Nowacek et al., 2007; Southall et al., 2007; Go¨tz et al., 2009, Southall et al., 2019a). The degree of effect is intrinsically related to the signal characteristics, received level, distance from the source, and duration of the sound exposure. In general, sudden, high level sounds can cause hearing loss, as can longer exposures to lower level sounds. Temporary or permanent loss of hearing can occur after exposure to noise, and occurs almost exclusively for noise within an animal’s hearing range. Note that in the following discussion, we refer in many cases to a review article concerning studies of noise-induced hearing loss conducted from 1996–2015 (i.e., Finneran, 2015). For study-specific citations, please see that work. We first describe general manifestations of acoustic effects before providing discussion specific to the Navy’s activities. Richardson et al. (1995) described zones of increasing intensity of effect that might be expected to occur, in relation to distance from a source and assuming that the signal is within an animal’s hearing range. First is the area within which the acoustic signal would be audible (potentially perceived) to the animal, but not strong enough to elicit any overt behavioral or physiological response. The next zone corresponds with the area where the signal is audible to the animal and of sufficient intensity to elicit behavioral or physiological responsiveness. Third is a zone within which, for signals of high intensity, the received level is sufficient to potentially cause discomfort or tissue damage to auditory systems. Overlaying these zones to a certain extent is the area within which masking (i.e., when a sound interferes with or masks the ability of an animal to detect a signal of interest that is above the absolute hearing threshold) may occur; the E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules masking zone may be highly variable in size. We also describe more severe potential effects (i.e., certain nonauditory physical or physiological effects). Potential effects from impulsive sound sources can range in severity from effects such as behavioral disturbance or tactile perception to physical discomfort, slight injury of the internal organs and the auditory system, or mortality (Yelverton et al., 1973). Non-auditory physiological effects or injuries that theoretically might occur in marine mammals exposed to high level underwater sound or as a secondary effect of extreme behavioral reactions (e.g., change in dive profile as a result of an avoidance reaction) caused by exposure to sound include neurological effects, bubble formation, resonance effects, and other types of organ or tissue damage (Cox et al., 2006; Southall et al., 2007; Zimmer and Tyack, 2007; Tal et al., 2015). Acoustic Sources Direct Physiological Effects Non-impulsive sources of sound can cause direct physiological effects including noise-induced loss of hearing sensitivity (or ‘‘threshold shift’’), nitrogen decompression, acousticallyinduced bubble growth, and injury due to sound-induced acoustic resonance. Only noise-induced hearing loss is anticipated to occur due to the Navy’s activities. Acoustically-induced (or mediated) bubble growth and other pressure-related physiological impacts are addressed briefly below, but are not expected to result from the Navy’s activities. Separately, an animal’s behavioral reaction to an acoustic exposure might lead to physiological effects that might ultimately lead to injury or death, which is discussed later in the Stranding subsection. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Hearing Loss—Threshold Shift Marine mammals exposed to highintensity sound, or to lower-intensity sound for prolonged periods, can experience hearing threshold shift, which is the loss of hearing sensitivity at certain frequency ranges after cessation of sound (Finneran, 2015). Threshold shift can be permanent (PTS), in which case the loss of hearing sensitivity is not fully recoverable, or temporary (TTS), in which case the animal’s hearing threshold would recover over time (Southall et al., 2007). TTS can last from minutes or hours to days (i.e., there is recovery back to baseline/pre-exposure levels), can occur within a specific frequency range (i.e., an animal might only have a temporary VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 loss of hearing sensitivity within a limited frequency band of its auditory range), and can be of varying amounts (e.g., an animal’s hearing sensitivity might be reduced by only 6 dB or reduced by 30 dB). While there is no simple functional relationship between TTS and PTS or other auditory injury (e.g., neural degeneration), as TTS increases, the likelihood that additional exposure sound pressure level (SPL) or duration will result in PTS or other injury also increases (see also the 2019 NWTT DSEIS/OEIS for additional discussion). Exposure thresholds for the occurrence of PTS or other auditory injury can therefore be defined based on a specific amount of TTS; that is, although an exposure has been shown to produce only TTS, we assume that any additional exposure may result in some PTS or other injury. The specific upper limit of TTS is based on experimental data showing amounts of TTS that have not resulted in PTS or injury. In other words, we do not need to know the exact functional relationship between TTS and PTS or other injury, we only need to know the upper limit for TTS before some PTS or injury is possible. In severe cases of PTS, there can be total or partial deafness, while in most cases the animal has an impaired ability to hear sounds in specific frequency ranges (Kryter, 1985). When PTS occurs, there is physical damage to the sound receptors in the ear (i.e., tissue damage), whereas TTS represents primarily tissue fatigue and is reversible (Southall et al., 2007). PTS is permanent (i.e., there is incomplete recovery back to baseline/pre-exposure levels), but also can occur in a specific frequency range and amount as mentioned above for TTS. In addition, other investigators have suggested that TTS is within the normal bounds of physiological variability and tolerance and does not represent physical injury (e.g., Ward, 1997). Therefore, NMFS does not consider TTS to constitute auditory injury. The following physiological mechanisms are thought to play a role in inducing auditory threshold shift: Effects to sensory hair cells in the inner ear that reduce their sensitivity; modification of the chemical environment within the sensory cells; residual muscular activity in the middle ear; displacement of certain inner ear membranes; increased blood flow; and post-stimulatory reduction in both efferent and sensory neural output (Southall et al., 2007). The amplitude, duration, frequency, temporal pattern, and energy distribution of sound exposure all can affect the amount of associated threshold shift and the PO 00000 Frm 00023 Fmt 4701 Sfmt 4702 33935 frequency range in which it occurs. Generally, the amount of threshold shift, and the time needed to recover from the effect, increase as amplitude and duration of sound exposure increases. Human non-impulsive noise exposure guidelines are based on the assumption that exposures of equal energy (the same sound exposure level (SEL)) produce equal amounts of hearing impairment regardless of how the sound energy is distributed in time (NIOSH, 1998). Previous marine mammal TTS studies have also generally supported this equal energy relationship (Southall et al., 2007). However, some more recent studies concluded that for all noise exposure situations the equal energy relationship may not be the best indicator to predict TTS onset levels (Mooney et al., 2009a and 2009b; Kastak et al., 2007). These studies highlight the inherent complexity of predicting TTS onset in marine mammals, as well as the importance of considering exposure duration when assessing potential impacts. Generally, with sound exposures of equal energy, those that were quieter (lower SPL) with longer duration were found to induce TTS onset at lower levels than those of louder (higher SPL) and shorter duration. Less threshold shift will occur from intermittent sounds than from a continuous exposure with the same energy (some recovery can occur between intermittent exposures) (Kryter et al., 1966; Ward, 1997; Mooney et al., 2009a, 2009b; Finneran et al., 2010). For example, one short but loud (higher SPL) sound exposure may induce the same impairment as one longer but softer (lower SPL) sound, which in turn may cause more impairment than a series of several intermittent softer sounds with the same total energy (Ward, 1997). Additionally, though TTS is temporary, very prolonged or repeated exposure to sound strong enough to elicit TTS, or shorter-term exposure to sound levels well above the TTS threshold can cause PTS, at least in terrestrial mammals (Kryter, 1985; Lonsbury-Martin et al., 1987). PTS is considered auditory injury (Southall et al., 2007). Irreparable damage to the inner or outer cochlear hair cells may cause PTS; however, other mechanisms are also involved, such as exceeding the elastic limits of certain tissues and membranes in the middle and inner ears and resultant changes in the chemical composition of the inner ear fluids (Southall et al., 2007). The NMFS Acoustic Technical Guidance (NMFS, 2018), which was used in the assessment of effects for this rule, compiled, interpreted, and E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33936 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules synthesized the best available scientific information for noise-induced hearing effects for marine mammals to derive updated thresholds for assessing the impacts of noise on marine mammal hearing. More recently, Southall et al. (2019a) evaluated Southall et al. (2007) and used updated scientific information to propose revised noise exposure criteria to predict onset of auditory effects in marine mammals (i.e., PTS and TTS onset). Southall et al. (2019a) note that the quantitative processes described and the resulting exposure criteria (i.e., thresholds and auditory weighting functions) are largely identical to those in Finneran (2016) and NMFS (2018). They only differ in that the Southall et al. (2019a) exposure criteria are more broadly applicable as they include all marine mammal species (rather than only those under NMFS jurisdiction) for all noise exposures (both in air and underwater for amphibious species) and, while the hearing group compositions are identical, they renamed the hearing groups. Many studies have examined noiseinduced hearing loss in marine mammals (see Finneran (2015) and Southall et al. (2019a) for summaries), however for cetaceans, published data on the onset of TTS are limited to the captive bottlenose dolphin, beluga, harbor porpoise, and Yangtze finless porpoise, and for pinnipeds in water, measurements of TTS are limited to harbor seals, elephant seals, and California sea lions. These studies examine hearing thresholds measured in marine mammals before and after exposure to intense sounds. The difference between the pre-exposure and post-exposure thresholds can then be used to determine the amount of threshold shift at various post-exposure times. NMFS has reviewed the available studies, which are summarized below (see also the 2019 NWTT DSEIS/OEIS which includes additional discussion on TTS studies related to sonar and other transducers). • The method used to test hearing may affect the resulting amount of measured TTS, with neurophysiological measures producing larger amounts of TTS compared to psychophysical measures (Finneran et al., 2007; Finneran, 2015). • The amount of TTS varies with the hearing test frequency. As the exposure SPL increases, the frequency at which the maximum TTS occurs also increases (Kastelein et al., 2014b). For high-level exposures, the maximum TTS typically occurs one-half to one octave above the exposure frequency (Finneran et al., 2007; Mooney et al., 2009a; Nachtigall VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 et al., 2004; Popov et al., 2011; Popov et al., 2013; Schlundt et al., 2000). The overall spread of TTS from tonal exposures can therefore extend over a large frequency range (i.e., narrowband exposures can produce broadband (greater than one octave) TTS). • The amount of TTS increases with exposure SPL and duration and is correlated with SEL, especially if the range of exposure durations is relatively small (Kastak et al., 2007; Kastelein et al., 2014b; Popov et al., 2014). As the exposure duration increases, however, the relationship between TTS and SEL begins to break down. Specifically, duration has a more significant effect on TTS than would be predicted on the basis of SEL alone (Finneran et al., 2010a; Kastak et al., 2005; Mooney et al., 2009a). This means if two exposures have the same SEL but different durations, the exposure with the longer duration (thus lower SPL) will tend to produce more TTS than the exposure with the higher SPL and shorter duration. In most acoustic impact assessments, the scenarios of interest involve shorter duration exposures than the marine mammal experimental data from which impact thresholds are derived; therefore, use of SEL tends to over-estimate the amount of TTS. Despite this, SEL continues to be used in many situations because it is relatively simple, more accurate than SPL alone, and lends itself easily to scenarios involving multiple exposures with different SPL. • Gradual increases of TTS may not be directly observable with increasing exposure levels, before the onset of PTS (Reichmuth et al., 2019). Similarly, PTS can occur without measurable behavioral modifications (Reichmuth et al., 2019). • The amount of TTS depends on the exposure frequency. Sounds at low frequencies, well below the region of best sensitivity, are less hazardous than those at higher frequencies, near the region of best sensitivity (Finneran and Schlundt, 2013). The onset of TTS— defined as the exposure level necessary to produce 6 dB of TTS (i.e., clearly above the typical variation in threshold measurements)—also varies with exposure frequency. At low frequencies, onset-TTS exposure levels are higher compared to those in the region of best sensitivity. • TTS can accumulate across multiple exposures, but the resulting TTS will be less than the TTS from a single, continuous exposure with the same SEL (Finneran et al., 2010a; Kastelein et al., 2014b; Kastelein et al., 2015b; Mooney et al., 2009b). This means that TTS predictions based on PO 00000 Frm 00024 Fmt 4701 Sfmt 4702 the total, cumulative SEL will overestimate the amount of TTS from intermittent exposures such as sonars and impulsive sources. • The amount of observed TTS tends to decrease with increasing time following the exposure; however, the relationship is not monotonic (i.e., increasing exposure does not always increase TTS). The time required for complete recovery of hearing depends on the magnitude of the initial shift; for relatively small shifts recovery may be complete in a few minutes, while large shifts (e.g., approximately 40 dB) may require several days for recovery. Under many circumstances TTS recovers linearly with the logarithm of time (Finneran et al., 2010a, 2010b; Finneran and Schlundt, 2013; Kastelein et al., 2012a; Kastelein et al., 2012b; Kastelein et al., 2013a; Kastelein et al., 2014b; Kastelein et al., 2014c; Popov et al., 2011; Popov et al., 2013; Popov et al., 2014). This means that for each doubling of recovery time, the amount of TTS will decrease by the same amount (e.g., 6 dB recovery per doubling of time). Nachtigall et al. (2018) and Finneran (2018) describe the measurements of hearing sensitivity of multiple odontocete species (bottlenose dolphin, harbor porpoise, beluga, and false killer whale) when a relatively loud sound was preceded by a warning sound. These captive animals were shown to reduce hearing sensitivity when warned of an impending intense sound. Based on these experimental observations of captive animals, the authors suggest that wild animals may dampen their hearing during prolonged exposures or if conditioned to anticipate intense sounds. Finneran recommends further investigation of the mechanisms of hearing sensitivity reduction in order to understand the implications for interpretation of existing TTS data obtained from captive animals, notably for considering TTS due to short duration, unpredictable exposures. Marine mammal hearing plays a critical role in communication with conspecifics and in interpretation of environmental cues for purposes such as predator avoidance and prey capture. Depending on the degree (elevation of threshold in dB), duration (i.e., recovery time), and frequency range of TTS, and the context in which it is experienced, TTS can have effects on marine mammals ranging from discountable to serious similar to those discussed in auditory masking, below. For example, a marine mammal may be able to readily compensate for a brief, relatively small amount of TTS in a non-critical frequency range that takes place during E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 a time where ambient noise is lower and there are not as many competing sounds present. Alternatively, a larger amount and longer duration of TTS sustained during a time when communication is critical for successful mother/calf interactions could have more serious impacts if it were in the same frequency band as the necessary vocalizations and of a severity that impeded communication. The fact that animals exposed to high levels of sound that would be expected to result in this physiological response would also be expected to have behavioral responses of a comparatively more severe or sustained nature is potentially more significant than simple existence of a TTS. However, it is important to note that TTS could occur due to longer exposures to sound at lower levels so that a behavioral response may not be elicited. Depending on the degree and frequency range, the effects of PTS on an animal could also range in severity, although it is considered generally more serious than TTS because it is a permanent condition. Of note, reduced hearing sensitivity as a simple function of aging has been observed in marine mammals, as well as humans and other taxa (Southall et al., 2007), so we can infer that strategies exist for coping with this condition to some degree, though likely not without some cost to the animal. Acoustically-Induced Bubble Formation Due to Sonars and Other PressureRelated Impacts One theoretical cause of injury to marine mammals is rectified diffusion (Crum and Mao, 1996), the process of increasing the size of a bubble by exposing it to a sound field. This process could be facilitated if the environment in which the ensonified bubbles exist is supersaturated with gas. Repetitive diving by marine mammals can cause the blood and some tissues to accumulate gas to a greater degree than is supported by the surrounding environmental pressure (Ridgway and Howard, 1979). The deeper and longer dives of some marine mammals (for example, beaked whales) are theoretically predicted to induce greater supersaturation (Houser et al., 2001b). If rectified diffusion were possible in marine mammals exposed to high-level sound, conditions of tissue supersaturation could theoretically speed the rate and increase the size of bubble growth. Subsequent effects due to tissue trauma and emboli would presumably mirror those observed in humans suffering from decompression sickness. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 It is unlikely that the short duration (in combination with the source levels) of sonar pings would be long enough to drive bubble growth to any substantial size, if such a phenomenon occurs. However, an alternative but related hypothesis has also been suggested: Stable bubbles could be destabilized by high-level sound exposures such that bubble growth then occurs through static diffusion of gas out of the tissues. In such a scenario the marine mammal would need to be in a gassupersaturated state for a long enough period of time for bubbles to become of a problematic size. Recent research with ex vivo supersaturated bovine tissues suggested that, for a 37 kHz signal, a sound exposure of approximately 215 dB referenced to (re) 1 mPa would be required before microbubbles became destabilized and grew (Crum et al., 2005). Assuming spherical spreading loss and a nominal sonar source level of 235 dB re: 1 mPa at 1 m, a whale would need to be within 10 m (33 ft) of the sonar dome to be exposed to such sound levels. Furthermore, tissues in the study were supersaturated by exposing them to pressures of 400–700 kilopascals for periods of hours and then releasing them to ambient pressures. Assuming the equilibration of gases with the tissues occurred when the tissues were exposed to the high pressures, levels of supersaturation in the tissues could have been as high as 400–700 percent. These levels of tissue supersaturation are substantially higher than model predictions for marine mammals (Houser et al., 2001; Saunders et al., 2008). It is improbable that this mechanism is responsible for stranding events or traumas associated with beaked whale strandings because both the degree of supersaturation and exposure levels observed to cause microbubble destabilization are unlikely to occur, either alone or in concert. Yet another hypothesis (decompression sickness) has speculated that rapid ascent to the surface following exposure to a startling sound might produce tissue gas saturation sufficient for the evolution of nitrogen bubbles (Jepson et al., 2003; Fernandez et al., 2005; Ferna´ndez et al., 2012). In this scenario, the rate of ascent would need to be sufficiently rapid to compromise behavioral or physiological protections against nitrogen bubble formation. Alternatively, Tyack et al. (2006) studied the deep diving behavior of beaked whales and concluded that: ‘‘Using current models of breath-hold diving, we infer that their natural diving behavior is inconsistent with known problems of acute nitrogen PO 00000 Frm 00025 Fmt 4701 Sfmt 4702 33937 supersaturation and embolism.’’ Collectively, these hypotheses can be referred to as ‘‘hypotheses of acoustically mediated bubble growth.’’ Although theoretical predictions suggest the possibility for acoustically mediated bubble growth, there is considerable disagreement among scientists as to its likelihood (Piantadosi and Thalmann, 2004; Evans and Miller, 2003; Cox et al., 2006; Rommel et al., 2006). Crum and Mao (1996) hypothesized that received levels would have to exceed 190 dB in order for there to be the possibility of significant bubble growth due to supersaturation of gases in the blood (i.e., rectified diffusion). Work conducted by Crum et al. (2005) demonstrated the possibility of rectified diffusion for short duration signals, but at SELs and tissue saturation levels that are highly improbable to occur in diving marine mammals. To date, energy levels (ELs) predicted to cause in vivo bubble formation within diving cetaceans have not been evaluated (NOAA, 2002b). Jepson et al. (2003, 2005) and Fernandez et al. (2004, 2005, 2012) concluded that in vivo bubble formation, which may be exacerbated by deep, long-duration, repetitive dives may explain why beaked whales appear to be relatively vulnerable to MF/HF sonar exposures. It has also been argued that traumas from some beaked whale strandings are consistent with gas emboli and bubbleinduced tissue separations (Jepson et al., 2003); however, there is no conclusive evidence of this (Rommel et al., 2006). Based on examination of sonar-associated strandings, Bernaldo de Quiros et al. (2019) list diagnostic features, the presence of all of which suggest gas and fat embolic syndrome for beaked whales stranded in association with sonar exposure. As described in additional detail in the Nitrogen Decompression subsection of the 2019 NWTT DSEIS/OEIS, marine mammals generally are thought to deal with nitrogen loads in their blood and other tissues, caused by gas exchange from the lungs under conditions of high ambient pressure during diving, through anatomical, behavioral, and physiological adaptations (Hooker et al., 2012). Although not a direct injury, variations in marine mammal diving behavior or avoidance responses have been hypothesized to result in nitrogen off-gassing in super-saturated tissues, possibly to the point of deleterious vascular and tissue bubble formation (Hooker et al., 2012; Jepson et al., 2003; Saunders et al., 2008) with resulting symptoms similar to decompression sickness, however the process is still not well understood. E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33938 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules In 2009, Hooker et al. tested two mathematical models to predict blood and tissue tension N2 (PN2) using field data from three beaked whale species: Northern bottlenose whales, Cuvier’s beaked whales, and Blainville’s beaked whales. The researchers aimed to determine if physiology (body mass, diving lung volume, and dive response) or dive behavior (dive depth and duration, changes in ascent rate, and diel behavior) would lead to differences in PN2 levels and thereby decompression sickness risk between species. In their study, they compared results for previously published time depth recorder data (Hooker and Baird, 1999; Baird et al., 2006, 2008) from Cuvier’s beaked whale, Blainville’s beaked whale, and northern bottlenose whale. They reported that diving lung volume and extent of the dive response had a large effect on end-dive PN2. Also, results showed that dive profiles had a larger influence on end-dive PN2 than body mass differences between species. Despite diel changes (i.e., variation that occurs regularly every day or most days) in dive behavior, PN2 levels showed no consistent trend. Model output suggested that all three species live with tissue PN2 levels that would cause a significant proportion of decompression sickness cases in terrestrial mammals. The authors concluded that the dive behavior of Cuvier’s beaked whale was different from both Blainville’s beaked whale and northern bottlenose whale, and resulted in higher predicted tissue and blood N2 levels (Hooker et al., 2009). They also suggested that the prevalence of Cuvier’s beaked whales stranding after naval sonar exercises could be explained by either a higher abundance of this species in the affected areas or by possible species differences in behavior and/or physiology related to MF active sonar (Hooker et al., 2009). Bernaldo de Quiros et al. (2012) showed that, among stranded whales, deep diving species of whales had higher abundances of gas bubbles compared to shallow diving species. Kvadsheim et al. (2012) estimated blood and tissue PN2 levels in species representing shallow, intermediate, and deep diving cetaceans following behavioral responses to sonar and their comparisons found that deep diving species had higher end-dive blood and tissue N2 levels, indicating a higher risk of developing gas bubble emboli compared with shallow diving species. Fahlmann et al. (2014) evaluated dive data recorded from sperm, killer, longfinned pilot, Blainville’s beaked and Cuvier’s beaked whales before and during exposure to low-frequency (1–2 VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 kHz), as defined by the authors, and mid-frequency (2–7 kHz) active sonar in an attempt to determine if either differences in dive behavior or physiological responses to sonar are plausible risk factors for bubble formation. The authors suggested that CO2 may initiate bubble formation and growth, while elevated levels of N2 may be important for continued bubble growth. The authors also suggest that if CO2 plays an important role in bubble formation, a cetacean escaping a sound source may experience increased metabolic rate, CO2 production, and alteration in cardiac output, which could increase risk of gas bubble emboli. However, as discussed in Kvadsheim et al. (2012), the actual observed behavioral responses to sonar from the species in their study (sperm, killer, long-finned pilot, Blainville’s beaked, and Cuvier’s beaked whales) did not imply any significantly increased risk of decompression sickness due to high levels of N2. Therefore, further information is needed to understand the relationship between exposure to stimuli, behavioral response (discussed in more detail below), elevated N2 levels, and gas bubble emboli in marine mammals. The hypotheses for gas bubble formation related to beaked whale strandings is that beaked whales potentially have strong avoidance responses to MF active sonars because they sound similar to their main predator, the killer whale (Cox et al., 2006; Southall et al., 2007; Zimmer and Tyack, 2007; Baird et al., 2008; Hooker et al., 2009). Further investigation is needed to assess the potential validity of these hypotheses. To summarize, while there are several hypotheses, there is little data directly connecting intense, anthropogenic underwater sounds with non-auditory physical effects in marine mammals. The available data do not support identification of a specific exposure level above which non-auditory effects can be expected (Southall et al., 2007) or any meaningful quantitative predictions of the numbers (if any) of marine mammals that might be affected in these ways. In addition, such effects, if they occur at all, would be expected to be limited to situations where marine mammals were exposed to high powered sounds at very close range over a prolonged period of time, which is not expected to occur based on the speed of the vessels operating sonar in combination with the speed and behavior of marine mammals in the vicinity of sonar. PO 00000 Frm 00026 Fmt 4701 Sfmt 4702 Injury Due to Sonar-Induced Acoustic Resonance An object exposed to its resonant frequency will tend to amplify its vibration at that frequency, a phenomenon called acoustic resonance. Acoustic resonance has been proposed as a potential mechanism by which a sonar or sources with similar operating characteristics could damage tissues of marine mammals. In 2002, NMFS convened a panel of government and private scientists to investigate the potential for acoustic resonance to occur in marine mammals (National Oceanic and Atmospheric Administration, 2002). They modeled and evaluated the likelihood that Navy mid-frequency sonar (2–10 kHz) caused resonance effects in beaked whales that eventually led to their stranding. The workshop participants concluded that resonance in air-filled structures was not likely to have played a primary role in the Bahamas stranding in 2000. They listed several reasons supporting this finding including (among others): Tissue displacements at resonance are estimated to be too small to cause tissue damage; tissue-lined air spaces most susceptible to resonance are too large in marine mammals to have resonant frequencies in the ranges used by midfrequency or low-frequency sonar; lung resonant frequencies increase with depth, and tissue displacements decrease with depth so if resonance is more likely to be caused at depth it is also less likely to have an affect there; and lung tissue damage has not been observed in any mass, multi-species stranding of beaked whales. The frequency at which resonance was predicted to occur in the animals’ lungs was 50 Hz, well below the frequencies used by the mid-frequency sonar systems associated with the Bahamas event. The workshop participants focused on the March 2000 stranding of beaked whales in the Bahamas as highquality data were available, but the workshop report notes that the results apply to other sonar-related stranding events. For the reasons given by the 2002 workshop participants, we do not anticipate injury due to sonar-induced acoustic resonance from the Navy’s proposed activities. Physiological Stress There is growing interest in monitoring and assessing the impacts of stress responses to sound in marine animals. Classic stress responses begin when an animal’s central nervous system perceives a potential threat to its homeostasis. That perception triggers stress responses regardless of whether a E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules stimulus actually threatens the animal; the mere perception of a threat is sufficient to trigger a stress response (Moberg, 2000; Sapolsky et al., 2005; Seyle, 1950). Once an animal’s central nervous system perceives a threat, it mounts a biological response or defense that consists of a combination of the four general biological defense responses: Behavioral responses, autonomic nervous system responses, neuroendocrine responses, or immune responses. According to Moberg (2000), in the case of many stressors, an animal’s first and sometimes most economical (in terms of biotic costs) response is behavioral avoidance of the potential stressor or avoidance of continued exposure to a stressor. An animal’s second line of defense to stressors involves the sympathetic part of the autonomic nervous system and the classical ‘‘fight or flight’’ response which includes the cardiovascular system, the gastrointestinal system, the exocrine glands, and the adrenal medulla to produce changes in heart rate, blood pressure, and gastrointestinal activity that humans commonly associate with ‘‘stress.’’ These responses have a relatively short duration and may or may not have significant long-term effect on an animal’s welfare. An animal’s third line of defense to stressors involves its neuroendocrine systems or sympathetic nervous systems; the system that has received the most study has been the hypothalmus-pituitary-adrenal system (also known as the HPA axis in mammals or the hypothalamuspituitary-interrenal axis in fish and some reptiles). Unlike stress responses associated with the autonomic nervous system, virtually all neuro-endocrine functions that are affected by stress— including immune competence, reproduction, metabolism, and behavior—are regulated by pituitary hormones. Stress-induced changes in the secretion of pituitary hormones have been implicated in failed reproduction (Moberg, 1987; Rivier and Rivest, 1991), altered metabolism (Elasser et al., 2000), reduced immune competence (Blecha, 2000), and behavioral disturbance (Moberg, 1987; Blecha, 2000). Increases in the circulation of glucocorticosteroids (cortisol, corticosterone, and aldosterone in marine mammals; see Romano et al., 2004) have been equated with stress for many years. The primary distinction between stress (which is adaptive and does not normally place an animal at risk) and distress is the biotic cost of the response. During a stress response, an animal uses glycogen stores that can be VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 quickly replenished once the stress is alleviated. In such circumstances, the cost of the stress response would not pose serious fitness consequences. However, when an animal does not have sufficient energy reserves to satisfy the energetic costs of a stress response, energy resources must be diverted from other biotic functions, which impairs those functions that experience the diversion. For example, when a stress response diverts energy away from growth in young animals, those animals may experience stunted growth. When a stress response diverts energy from a fetus, an animal’s reproductive success and its fitness will suffer. In these cases, the animals will have entered a prepathological or pathological state which is called ‘‘distress’’ (Seyle, 1950) or ‘‘allostatic loading’’ (McEwen and Wingfield, 2003). This pathological state of distress will last until the animal replenishes its energetic reserves sufficiently to restore normal function. Note that these examples involved a long-term (days or weeks) stress response exposure to stimuli. Relationships between these physiological mechanisms, animal behavior, and the costs of stress responses are well-studied through controlled experiments in both laboratory and free-ranging animals (for examples see, Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003; Krausman et al., 2004; Lankford et al., 2005; Reneerkens et al., 2002; Thompson and Hamer, 2000). However, it should be noted (and as is described in additional detail in the 2019 NWTT DSEIS/OEIS) that our understanding of the functions of various stress hormones (for example, cortisol), is based largely upon observations of the stress response in terrestrial mammals. Atkinson et al., 2015 note that the endocrine response of marine mammals to stress may not be the same as that of terrestrial mammals because of the selective pressures marine mammals faced during their evolution in an ocean environment. For example, due to the necessity of breathholding while diving and foraging at depth, the physiological role of epinephrine and norepinephrine (the catecholamines) in marine mammals might be different than in other mammals. Marine mammals naturally experience stressors within their environment and as part of their life histories. Changing weather and ocean conditions, exposure to disease and naturally occurring toxins, lack of prey availability, and interactions with predators all contribute to the stress a marine mammal experiences (Atkinson et al., 2015). Breeding cycles, periods of PO 00000 Frm 00027 Fmt 4701 Sfmt 4702 33939 fasting, and social interactions with members of the same species are also stressors, although they are natural components of an animal’s life history. Anthropogenic activities have the potential to provide additional stressors beyond those that occur naturally (Fair et al., 2014; Meissner et al., 2015; Rolland et al., 2012). Anthropogenic stressors potentially include such things as fishery interactions, pollution, tourism, and ocean noise. Acoustically induced stress in marine mammals is not well understood. There are ongoing efforts to improve our understanding of how stressors impact marine mammal populations (e.g., King et al., 2015; New et al., 2013a; New et al., 2013b; Pirotta et al., 2015a), however little data exist on the consequences of sound-induced stress response (acute or chronic). Factors potentially affecting a marine mammal’s response to a stressor include the individual’s life history stage, sex, age, reproductive status, overall physiological and behavioral plasticity, and whether they are naı¨ve or experienced with the sound (e.g., prior experience with a stressor may result in a reduced response due to habituation (Finneran and Branstetter, 2013; St. Aubin and Dierauf, 2001a)). Stress responses due to exposure to anthropogenic sounds or other stressors and their effects on marine mammals have been reviewed (Fair and Becker, 2000; Romano et al., 2002b) and, more rarely, studied in wild populations (e.g., Romano et al., 2002a). For example, Rolland et al. (2012) found that noise reduction from reduced ship traffic in the Bay of Fundy was associated with decreased stress in North Atlantic right whales. These and other studies lead to a reasonable expectation that some marine mammals will experience physiological stress responses upon exposure to acoustic stressors and that it is possible that some of these would be classified as ‘‘distress.’’ In addition, any animal experiencing TTS would likely also experience stress responses (NRC, 2003). Other research has also investigated the impact from vessels (both whalewatching and general vessel traffic noise), and demonstrated impacts do occur (Bain, 2002; Erbe, 2002; Lusseau, 2006; Williams et al., 2006; Williams et al., 2009; Noren et al., 2009; Read et al., 2014; Rolland et al., 2012; Skarke et al., 2014; Williams et al., 2013; Williams et al., 2014a; Williams et al., 2014b; Pirotta et al., 2015). This body of research has generally investigated impacts associated with the presence of chronic stressors, which differ significantly from the proposed Navy training and testing E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33940 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules vessel activities in the NWTT Study Area. For example, in an analysis of energy costs to killer whales, Williams et al. (2009) suggested that whalewatching in Canada’s Johnstone Strait resulted in lost feeding opportunities due to vessel disturbance, which could carry higher costs than other measures of behavioral change might suggest. Ayres et al. (2012) reported on research in the Salish Sea (Washington state) involving the measurement of southern resident killer whale fecal hormones to assess two potential threats to the species recovery: Lack of prey (salmon) and impacts to behavior from vessel traffic. Ayres et al. (2012) suggested that the lack of prey overshadowed any population-level physiological impacts on southern resident killer whales from vessel traffic. In a conceptual model developed by the Population Consequences of Acoustic Disturbance (PCAD) working group, serum hormones were identified as possible indicators of behavioral effects that are translated into altered rates of reproduction and mortality (NRC, 2005). The Office of Naval Research hosted a workshop (Effects of Stress on Marine Mammals Exposed to Sound) in 2009 that focused on this topic (ONR, 2009). Ultimately, the PCAD working group issued a report (Cochrem, 2014) that summarized information compiled from 239 papers or book chapters relating to stress in marine mammals and concluded that stress responses can last from minutes to hours and, while we typically focus on adverse stress responses, stress response is part of a natural process to help animals adjust to changes in their environment and can also be either neutral or beneficial. Most sound-induced stress response studies in marine mammals have focused on acute responses to sound either by measuring catecholamines or by measuring heart rate as an assumed proxy for an acute stress response. Belugas demonstrated no catecholamine response to the playback of oil drilling sounds (Thomas et al., 1990) but showed a small but statistically significant increase in catecholamines following exposure to impulsive sounds produced from a seismic water gun (Romano et al., 2004). A bottlenose dolphin exposed to the same seismic water gun signals did not demonstrate a catecholamine response, but did demonstrate a statistically significant elevation in aldosterone (Romano et al., 2004), albeit the increase was within the normal daily variation observed in this species (St. Aubin et al., 1996). Increases in heart rate were observed in bottlenose dolphins to which known VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 calls of other dolphins were played, although no increase in heart rate was observed when background tank noise was played back (Miksis et al., 2001). Unfortunately, in this study, it cannot be determined whether the increase in heart rate was due to stress or an anticipation of being reunited with the dolphin to which the vocalization belonged. Similarly, a young beluga’s heart rate was observed to increase during exposure to noise, with increases dependent upon the frequency band of noise and duration of exposure, and with a sharp decrease to normal or below normal levels upon cessation of the exposure (Lyamin et al., 2011). Spectral analysis of heart rate variability corroborated direct measures of heart rate (Bakhchina et al., 2017). This response might have been in part due to the conditions during testing, the young age of the animal, and the novelty of the exposure; a year later the exposure was repeated at a slightly higher received level and there was no heart rate response, indicating the beluga whale may have acclimated to the noise exposure. Kvadsheim et al. (2010) measured the heart rate of captive hooded seals during exposure to sonar signals and found an increase in the heart rate of the seals during exposure periods versus control periods when the animals were at the surface. When the animals dove, the normal dive-related bradycardia (decrease in heart rate) was not impacted by the sonar exposure. Similarly, Thompson et al. (1998) observed a rapid but short-lived decrease in heart rates in harbor and grey seals exposed to seismic air guns (cited in Gordon et al., 2003). Williams et al. (2017) recently monitored the heart rates of narwhals released from capture and found that a profound dive bradycardia persisted, even though exercise effort increased dramatically as part of their escape response following release. Thus, although some limited evidence suggests that tachycardia might occur as part of the acute stress response of animals that are at the surface, the dive bradycardia persists during diving and might be enhanced in response to an acute stressor. Despite the limited amount of data available on sound-induced stress responses for marine mammals exposed to anthropogenic sounds, studies of other marine animals and terrestrial animals would also lead us to expect that some marine mammals experience physiological stress responses and, perhaps, physiological responses that would be classified as ‘‘distress’’ upon exposure to high-frequency, midfrequency, and low-frequency sounds. PO 00000 Frm 00028 Fmt 4701 Sfmt 4702 For example, Jansen (1998) reported on the relationship between acoustic exposures and physiological responses that are indicative of stress responses in humans (e.g., elevated respiration and increased heart rates). Jones (1998) reported on reductions in human performance when faced with acute, repetitive exposures to acoustic disturbance. Trimper et al. (1998) reported on the physiological stress responses of osprey to low-level aircraft noise while Krausman et al. (2004) reported on the auditory and physiological stress responses of endangered Sonoran pronghorn to military overflights. However, take due to aircraft noise is not anticipated as a result of the Navy’s activities. Smith et al. (2004a, 2004b) identified noiseinduced physiological transient stress responses in hearing-specialist fish (i.e., goldfish) that accompanied short- and long-term hearing losses. Welch and Welch (1970) reported physiological and behavioral stress responses that accompanied damage to the inner ears of fish and several mammals. Auditory Masking Sound can disrupt behavior through masking, or interfering with, an animal’s ability to detect, recognize, or discriminate between acoustic signals of interest (e.g., those used for intraspecific communication and social interactions, prey detection, predator avoidance, or navigation) (Richardson et al., 1995; Erbe and Farmer, 2000; Tyack, 2000; Erbe et al., 2016). Masking occurs when the receipt of a sound is interfered with by another coincident sound at similar frequencies and at similar or higher intensity, and may occur whether the sound is natural (e.g., snapping shrimp, wind, waves, precipitation) or anthropogenic (e.g., shipping, sonar, seismic exploration) in origin. As described in detail in the 2019 NWTT DSEIS/OEIS, the ability of a noise source to mask biologically important sounds depends on the characteristics of both the noise source and the signal of interest (e.g., signal-to-noise ratio, temporal variability, direction), in relation to each other and to an animal’s hearing abilities (e.g., sensitivity, frequency range, critical ratios, frequency discrimination, directional discrimination, age, or TTS hearing loss), and existing ambient noise and propagation conditions. Masking these acoustic signals can disturb the behavior of individual animals, groups of animals, or entire populations. Masking can lead to behavioral changes including vocal changes (e.g., Lombard effect, increasing amplitude, or changing frequency), cessation of E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules foraging, and leaving an area, to both signalers and receivers, in an attempt to compensate for noise levels (Erbe et al., 2016). In humans, significant masking of tonal signals occurs as a result of exposure to noise in a narrow band of similar frequencies. As the sound level increases, though, the detection of frequencies above those of the masking stimulus decreases also. This principle is expected to apply to marine mammals as well because of common biomechanical cochlear properties across taxa. Under certain circumstances, marine mammals experiencing significant masking could also be impaired from maximizing their performance fitness in survival and reproduction. Therefore, when the coincident (masking) sound is man-made, it may be considered harassment when disrupting or altering critical behaviors. It is important to distinguish TTS and PTS, which persist after the sound exposure, from masking, which only occurs during the sound exposure. Because masking (without resulting in threshold shift) is not associated with abnormal physiological function, it is not considered a physiological effect, but rather a potential behavioral effect. Richardson et al. (1995b) argued that the maximum radius of influence of an industrial noise (including broadband low-frequency sound transmission) on a marine mammal is the distance from the source to the point at which the noise can barely be heard. This range is determined by either the hearing sensitivity (including critical ratios, or the lowest signal-to-noise ratio in which animals can detect a signal, Finneran and Branstetter, 2013; Johnson et al., 1989; Southall et al., 2000) of the animal or the background noise level present. Industrial masking is most likely to affect some species’ ability to detect communication calls and natural sounds (i.e., surf noise, prey noise, etc.; Richardson et al., 1995). The frequency range of the potentially masking sound is important in determining any potential behavioral impacts. For example, low-frequency signals may have less effect on highfrequency echolocation sounds produced by odontocetes but are more likely to affect detection of mysticete communication calls and other potentially important natural sounds such as those produced by surf and some prey species. The masking of communication signals by anthropogenic noise may be considered as a reduction in the communication space of animals (e.g., Clark et al., 2009; Matthews et al., 2016) and may result in VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 energetic or other costs as animals change their vocalization behavior (e.g., Miller et al., 2000; Foote et al., 2004; Parks et al., 2007; Di Iorio and Clark, 2009; Holt et al., 2009). Masking can be reduced in situations where the signal and noise come from different directions (Richardson et al., 1995), through amplitude modulation of the signal, or through other compensatory behaviors (Houser and Moore, 2014). Masking can be tested directly in captive species (e.g., Erbe, 2008), but in wild populations it must be either modeled or inferred from evidence of masking compensation. There are few studies addressing real-world masking sounds likely to be experienced by marine mammals in the wild (e.g., Branstetter et al., 2013). The echolocation calls of toothed whales are subject to masking by highfrequency sound. Human data indicate low-frequency sound can mask highfrequency sounds (i.e., upward masking). Studies on captive odontocetes by Au et al. (1974, 1985, 1993) indicate that some species may use various processes to reduce masking effects (e.g., adjustments in echolocation call intensity or frequency as a function of background noise conditions). There is also evidence that the directional hearing abilities of odontocetes are useful in reducing masking at the highfrequencies these cetaceans use to echolocate, but not at the low-tomoderate frequencies they use to communicate (Zaitseva et al., 1980). A study by Nachtigall and Supin (2008) showed that false killer whales adjust their hearing to compensate for ambient sounds and the intensity of returning echolocation signals. Impacts on signal detection, measured by masked detection thresholds, are not the only important factors to address when considering the potential effects of masking. As marine mammals use sound to recognize conspecifics, prey, predators, or other biologically significant sources (Branstetter et al., 2016), it is also important to understand the impacts of masked recognition thresholds (often called ‘‘informational masking’’). Branstetter et al., 2016 measured masked recognition thresholds for whistle-like sounds of bottlenose dolphins and observed that they are approximately 4 dB above detection thresholds (energetic masking) for the same signals. Reduced ability to recognize a conspecific call or the acoustic signature of a predator could have severe negative impacts. Branstetter et al., 2016 observed that if ‘‘quality communication’’ is set at 90 percent recognition the output of communication space models (which PO 00000 Frm 00029 Fmt 4701 Sfmt 4702 33941 are based on 50 percent detection) would likely result in a significant decrease in communication range. As marine mammals use sound to recognize predators (Allen et al., 2014; Cummings and Thompson, 1971; Cure´ et al., 2015; Fish and Vania, 1971), the presence of masking noise may also prevent marine mammals from responding to acoustic cues produced by their predators, particularly if it occurs in the same frequency band. For example, harbor seals that reside in the coastal waters off British Columbia are frequently targeted by mammal-eating killer whales. The seals acoustically discriminate between the calls of mammal-eating and fish-eating killer whales (Deecke et al., 2002), a capability that should increase survivorship while reducing the energy required to attend to all killer whale calls. Similarly, sperm whales (Cure´ et al., 2016; Isojunno et al., 2016), long-finned pilot whales (Visser et al., 2016), and humpback whales (Cure´ et al., 2015) changed their behavior in response to killer whale vocalization playbacks; these findings indicate that some recognition of predator cues could be missed if the killer whale vocalizations were masked. The potential effects of masked predator acoustic cues depends on the duration of the masking noise and the likelihood of a marine mammal encountering a predator during the time that detection and recognition of predator cues are impeded. Redundancy and context can also facilitate detection of weak signals. These phenomena may help marine mammals detect weak sounds in the presence of natural or manmade noise. Most masking studies in marine mammals present the test signal and the masking noise from the same direction. The dominant background noise may be highly directional if it comes from a particular anthropogenic source such as a ship or industrial site. Directional hearing may significantly reduce the masking effects of these sounds by improving the effective signal-to-noise ratio. Masking affects both senders and receivers of acoustic signals and can potentially have long-term chronic effects on marine mammals at the population level as well as at the individual level. Low-frequency ambient sound levels have increased by as much as 20 dB (more than three times in terms of SPL) in the world’s ocean from pre-industrial periods, with most of the increase from distant commercial shipping (Hildebrand, 2009). All anthropogenic sound sources, but especially chronic and lower-frequency signals (e.g., from commercial vessel E:\FR\FM\02JNP2.SGM 02JNP2 33942 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 traffic), contribute to elevated ambient sound levels, thus intensifying masking. Impaired Communication In addition to making it more difficult for animals to perceive and recognize acoustic cues in their environment, anthropogenic sound presents separate challenges for animals that are vocalizing. When they vocalize, animals are aware of environmental conditions that affect the ‘‘active space’’ (or communication space) of their vocalizations, which is the maximum area within which their vocalizations can be detected before it drops to the level of ambient noise (Brenowitz, 2004; Brumm et al., 2004; Lohr et al., 2003). Animals are also aware of environmental conditions that affect whether listeners can discriminate and recognize their vocalizations from other sounds, which is more important than simply detecting that a vocalization is occurring (Brenowitz, 1982; Brumm et al., 2004; Dooling, 2004, Marten and Marler, 1977; Patricelli et al., 2006). Most species that vocalize have evolved with an ability to make adjustments to their vocalizations to increase the signal-to-noise ratio, active space, and recognizability/distinguishability of their vocalizations in the face of temporary changes in background noise (Brumm et al., 2004; Patricelli et al., 2006). Vocalizing animals can make adjustments to vocalization characteristics such as the frequency structure, amplitude, temporal structure, and temporal delivery (repetition rate), or may cease to vocalize. Many animals will combine several of these strategies to compensate for high levels of background noise. Anthropogenic sounds that reduce the signal-to-noise ratio of animal vocalizations, increase the masked auditory thresholds of animals listening for such vocalizations, or reduce the active space of an animal’s vocalizations impair communication between animals. Most animals that vocalize have evolved strategies to compensate for the effects of short-term or temporary increases in background or ambient noise on their songs or calls. Although the fitness consequences of these vocal adjustments are not directly known in all instances, like most other trade-offs animals must make, some of these strategies probably come at a cost (Patricelli et al., 2006). Shifting songs and calls to higher frequencies may also impose energetic costs (Lambrechts, 1996). For example, in birds, vocalizing more loudly in noisy environments may have energetic costs that decrease the net benefits of vocal adjustment and VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 alter a bird’s energy budget (Brumm, 2004; Wood and Yezerinac, 2006). Marine mammals are also known to make vocal changes in response to anthropogenic noise. In cetaceans, vocalization changes have been reported from exposure to anthropogenic noise sources such as sonar, vessel noise, and seismic surveying (see the following for examples: Gordon et al., 2003; Di Iorio and Clark, 2010; Hatch et al., 2012; Holt et al., 2008; Holt et al., 2011; Lesage et al., 1999; McDonald et al., 2009; Parks et al., 2007, Risch et al., 2012, Rolland et al., 2012), as well as changes in the natural acoustic environment (Dunlop et al., 2014). Vocal changes can be temporary, or can be persistent. For example, model simulation suggests that the increase in starting frequency for the North Atlantic right whale upcall over the last 50 years resulted in increased detection ranges between right whales. The frequency shift, coupled with an increase in call intensity by 20 dB, led to a call detectability range of less than 3 km to over 9 km (Tennessen and Parks, 2016). Holt et al. (2008) measured killer whale call source levels and background noise levels in the one to 40 kHz band and reported that the whales increased their call source levels by one dB SPL for every one dB SPL increase in background noise level. Similarly, another study on St. Lawrence River belugas reported a similar rate of increase in vocalization activity in response to passing vessels (Scheifele et al., 2005). Di Iorio and Clark (2010) showed that blue whale calling rates vary in association with seismic sparker survey activity, with whales calling more on days with surveys than on days without surveys. They suggested that the whales called more during seismic survey periods as a way to compensate for the elevated noise conditions. In some cases, these vocal changes may have fitness consequences, such as an increase in metabolic rates and oxygen consumption, as observed in bottlenose dolphins when increasing their call amplitude (Holt et al., 2015). A switch from vocal communication to physical, surface-generated sounds such as pectoral fin slapping or breaching was observed for humpback whales in the presence of increasing natural background noise levels, indicating that adaptations to masking may also move beyond vocal modifications (Dunlop et al., 2010). While these changes all represent possible tactics by the sound-producing animal to reduce the impact of masking, the receiving animal can also reduce masking by using active listening strategies such as orienting to the sound source, moving to a quieter location, or PO 00000 Frm 00030 Fmt 4701 Sfmt 4702 reducing self-noise from hydrodynamic flow by remaining still. The temporal structure of noise (e.g., amplitude modulation) may also provide a considerable release from masking through comodulation masking release (a reduction of masking that occurs when broadband noise, with a frequency spectrum wider than an animal’s auditory filter bandwidth at the frequency of interest, is amplitude modulated) (Branstetter and Finneran, 2008; Branstetter et al., 2013). Signal type (e.g., whistles, burst-pulse, sonar clicks) and spectral characteristics (e.g., frequency modulated with harmonics) may further influence masked detection thresholds (Branstetter et al., 2016; Cunningham et al., 2014). Masking Due to Sonar and Other Transducers The functional hearing ranges of mysticetes, odontocetes, and pinnipeds underwater overlap the frequencies of the sonar sources used in the Navy’s low-frequency active sonar (LFAS)/midfrequency active sonar (MFAS)/highfrequency active sonar (HFAS) training and testing exercises. Additionally, almost all affected species’ vocal repertoires span across the frequencies of these sonar sources used by the Navy. The closer the characteristics of the masking signal to the signal of interest, the more likely masking is to occur. Masking by low-frequency or midfrequency active sonar (LFAS and MFAS) with relatively low-duty cycles is not anticipated (or would be of very short duration) for most cetaceans as sonar signals occur over a relatively short duration and narrow bandwidth (overlapping with only a small portion of the hearing range). LFAS could overlap in frequency with mysticete vocalizations, however LFAS does not overlap with vocalizations for most marine mammal species. For example, in the presence of LFAS, humpback whales were observed to increase the length of their songs (Fristrup et al., 2003; Miller et al., 2000), potentially due to the overlap in frequencies between the whale song and the LFAS. While dolphin whistles and MFAS are similar in frequency, masking is not anticipated (or would be of very short duration) due to the low-duty cycle of most sonars. As described in additional detail the 2019 NWTT DSEIS/OEIS, newer highduty cycle or continuous active sonars have more potential to mask vocalizations. These sonars transmit more frequently (greater than 80 percent duty cycle) than traditional sonars, but at a substantially lower source level. HFAS, such as pingers that operate at E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 higher repetition rates (e.g., 2–10 kHz with harmonics up to 19 kHz, 76 to 77 pings per minute) (Culik et al., 2001), also operate at lower source levels and have faster attenuation rates due to the higher frequencies used. These lower source levels limit the range of impacts, however compared to traditional sonar systems, individuals close to the source are likely to experience masking at longer time scales. The frequency range at which high-duty cycle systems operate overlaps the vocalization frequency of many mid-frequency cetaceans. Continuous noise at the same frequency of communicative vocalizations may cause disruptions to communication, social interactions, acoustically mediated cooperative behaviors, and important environmental cues. There is also the potential for the mid-frequency sonar signals to mask important environmental cues (e.g., predator or conspectic acoustic cues), possibly affecting survivorship for targeted animals. While there are currently no available studies of the impacts of high-duty cycle sonars on marine mammals, masking due to these systems is likely analogous to masking produced by other continuous sources (e.g., vessel noise and low-frequency cetaceans), and would likely have similar short-term consequences, though longer in duration due to the duration of the masking noise. These may include changes to vocalization amplitude and frequency (Brumm and Slabbekoorn, 2005; Hotchkin and Parks, 2013) and behavioral impacts such as avoidance of the area and interruptions to foraging or other essential behaviors (Gordon et al., 2003). Long-term consequences could include changes to vocal behavior and vocalization structure (Foote et al., 2004; Parks et al., 2007), abandonment of habitat if masking occurs frequently enough to significantly impair communication (Brumm and Slabbekoorn, 2005), a potential decrease in survivorship if predator vocalizations are masked (Brumm and Slabbekoorn, 2005), and a potential decrease in recruitment if masking interferes with reproductive activities or mother-calf communication (Gordon et al., 2003). Masking Due to Vessel Noise Masking is more likely to occur in the presence of broadband, relatively continuous noise sources such as vessels. Several studies have shown decreases in marine mammal communication space and changes in behavior as a result of the presence of vessel noise. For example, right whales were observed to shift the frequency content of their calls upward while VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 reducing the rate of calling in areas of increased anthropogenic noise (Parks et al., 2007) as well as increasing the amplitude (intensity) of their calls (Parks, 2009; Parks et al., 2011). Fournet et al. (2018) observed that humpback whales in Alaska responded to increasing ambient sound levels (natural and anthropogenic) by increasing the source levels of their calls (non-song vocalizations). Clark et al. (2009) also observed that right whales communication space decreased by up to 84 percent in the presence of vessels (Clark et al., 2009). Cholewiak et al. (2018) also observed loss in communication space in Stellwagen National Marine Sanctuary for North Atlantic right whales, fin whales, and humpback whales with increased ambient noise and shipping noise. Gabriele et al. (2018) modeled the effects of vessel traffic sound on communication space in Glacier Bay National Park in Alaska and found that typical summer vessel traffic in the Park causes losses of communication space to singing whales (reduced by 13–28 percent), calling whales (18–51 percent), and roaring seals (32–61 percent), particularly during daylight hours and even in the absence of cruise ships. Dunlop (2019) observed that an increase in vessel noise reduced modelled communication space and resulted in significant reduction in group social interactions in Australian humpback whales. However, communication signal masking did not fully explain this change in social behavior in the model, indicating there may also be an additional effect of the physical presence of the vessel on social behavior (Dunlop, 2019). Although humpback whales off Australia did not change the frequency or duration of their vocalizations in the presence of ship noise, their source levels were lower than expected based on source level changes to wind noise, potentially indicating some signal masking (Dunlop, 2016). Multiple delphinid species have also been shown to increase the minimum or maximum frequencies of their whistles in the presence of anthropogenic noise and reduced communication space (for examples see: Holt et al., 2008; Holt et al., 2011; Gervaise et al., 2012; Williams et al., 2013; Hermannsen et al., 2014; Papale et al., 2015; Liu et al., 2017). Behavioral Response/Disturbance Behavioral responses to sound are highly variable and context-specific. Many different variables can influence an animal’s perception of and response to (nature and magnitude) an acoustic event. An animal’s prior experience PO 00000 Frm 00031 Fmt 4701 Sfmt 4702 33943 with a sound or sound source affects whether it is less likely (habituation) or more likely (sensitization) to respond to certain sounds in the future (animals can also be innately predisposed to respond to certain sounds in certain ways) (Southall et al., 2007). Related to the sound itself, the perceived nearness of the sound, bearing of the sound (approaching vs. retreating), the similarity of a sound to biologically relevant sounds in the animal’s environment (i.e., calls of predators, prey, or conspecifics), and familiarity of the sound may affect the way an animal responds to the sound (Southall et al., 2007, DeRuiter et al., 2013). Individuals (of different age, gender, reproductive status, etc.) among most populations will have variable hearing capabilities, and differing behavioral sensitivities to sounds that will be affected by prior conditioning, experience, and current activities of those individuals. Often, specific acoustic features of the sound and contextual variables (i.e., proximity, duration, or recurrence of the sound or the current behavior that the marine mammal is engaged in or its prior experience), as well as entirely separate factors such as the physical presence of a nearby vessel, may be more relevant to the animal’s response than the received level alone. For example, Goldbogen et al. (2013) demonstrated that individual behavioral state was critically important in determining response of blue whales to sonar, noting that some individuals engaged in deep (≤50 m) feeding behavior had greater dive responses than those in shallow feeding or non-feeding conditions. Some blue whales in the Goldbogen et al. (2013) study that were engaged in shallow feeding behavior demonstrated no clear changes in diving or movement even when received levels (RLs) were high (∼160 dB re: 1mPa) for exposures to 3–4 kHz sonar signals, while others showed a clear response at exposures at lower received levels of sonar and pseudorandom noise. Studies by DeRuiter et al. (2012) indicate that variability of responses to acoustic stimuli depends not only on the species receiving the sound and the sound source, but also on the social, behavioral, or environmental contexts of exposure. Another study by DeRuiter et al. (2013) examined behavioral responses of Cuvier’s beaked whales to MF sonar and found that whales responded strongly at low received levels (RL of 89–127 dB re: 1mPa) by ceasing normal fluking and echolocation, swimming rapidly away, and extending both dive duration and subsequent non-foraging intervals when E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33944 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules the sound source was 3.4–9.5 km away. Importantly, this study also showed that whales exposed to a similar range of received levels (78–106 dB re: 1 mPa) from distant sonar exercises (118 km away) did not elicit such responses, suggesting that context may moderate reactions. Ellison et al. (2012) outlined an approach to assessing the effects of sound on marine mammals that incorporates contextual-based factors. The authors recommend considering not just the received level of sound, but also the activity the animal is engaged in at the time the sound is received, the nature and novelty of the sound (i.e., is this a new sound from the animal’s perspective), and the distance between the sound source and the animal. They submit that this ‘‘exposure context,’’ as described, greatly influences the type of behavioral response exhibited by the animal. Forney et al. (2017) also point out that an apparent lack of response (e.g., no displacement or avoidance of a sound source) may not necessarily mean there is no cost to the individual or population, as some resources or habitats may be of such high value that animals may choose to stay, even when experiencing stress or hearing loss. Forney et al. (2017) recommend considering both the costs of remaining in an area of noise exposure such as TTS, PTS, or masking, which could lead to an increased risk of predation or other threats or a decreased capability to forage, and the costs of displacement, including potential increased risk of vessel strike, increased risks of predation or competition for resources, or decreased habitat suitable for foraging, resting, or socializing. This sort of contextual information is challenging to predict with accuracy for ongoing activities that occur over large spatial and temporal expanses. However, distance is one contextual factor for which data exist to quantitatively inform a take estimate, and the method for predicting Level B harassment in this rule does consider distance to the source. Other factors are often considered qualitatively in the analysis of the likely consequences of sound exposure, where supporting information is available. Friedlaender et al. (2016) provided the first integration of direct measures of prey distribution and density variables incorporated into across-individual analyses of behavior responses of blue whales to sonar, and demonstrated a five-fold increase in the ability to quantify variability in blue whale diving behavior. These results illustrate that responses evaluated without such measurements for foraging animals may VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 be misleading, which again illustrates the context-dependent nature of the probability of response. Exposure of marine mammals to sound sources can result in, but is not limited to, no response or any of the following observable responses: Increased alertness; orientation or attraction to a sound source; vocal modifications; cessation of feeding; cessation of social interaction; alteration of movement or diving behavior; habitat abandonment (temporary or permanent); and, in severe cases, panic, flight, stampede, or stranding, potentially resulting in death (Southall et al., 2007). A review of marine mammal responses to anthropogenic sound was first conducted by Richardson (1995). More recent reviews (Nowacek et al., 2007; DeRuiter et al., 2012 and 2013; Ellison et al., 2012; Gomez et al., 2016) address studies conducted since 1995 and focused on observations where the received sound level of the exposed marine mammal(s) was known or could be estimated. Gomez et al. (2016) conducted a review of the literature considering the contextual information of exposure in addition to received level and found that higher received levels were not always associated with more severe behavioral responses and vice versa. Southall et al. (2016) states that results demonstrate that some individuals of different species display clear yet varied responses, some of which have negative implications, while others appear to tolerate high levels, and that responses may not be fully predictable with simple acoustic exposure metrics (e.g., received sound level). Rather, the authors state that differences among species and individuals along with contextual aspects of exposure (e.g., behavioral state) appear to affect response probability. The following subsections provide examples of behavioral responses that provide an idea of the variability in behavioral responses that would be expected given the differential sensitivities of marine mammal species to sound and the wide range of potential acoustic sources to which a marine mammal may be exposed. Behavioral responses that could occur for a given sound exposure should be determined from the literature that is available for each species, or extrapolated from closely related species when no information exists, along with contextual factors. Flight Response A flight response is a dramatic change in normal movement to a directed and rapid movement away from the perceived location of a sound source. PO 00000 Frm 00032 Fmt 4701 Sfmt 4702 The flight response differs from other avoidance responses in the intensity of the response (e.g., directed movement, rate of travel). Relatively little information on flight responses of marine mammals to anthropogenic signals exist, although observations of flight responses to the presence of predators have occurred (Connor and Heithaus, 1996). The result of a flight response could range from brief, temporary exertion and displacement from the area where the signal provokes flight to, in extreme cases, being a component of marine mammal strandings associated with sonar activities (Evans and England, 2001). If marine mammals respond to Navy vessels that are transmitting active sonar in the same way that they might respond to a predator, their probability of flight responses should increase when they perceive that Navy vessels are approaching them directly, because a direct approach may convey detection and intent to capture (Burger and Gochfeld, 1981, 1990; Cooper, 1997, 1998). There are limited data on flight response for marine mammals in water; however, there are examples of this response in species on land. For instance, the probability of flight responses in Dall’s sheep Ovis dalli dalli (Frid, 2001), hauled-out ringed seals Phoca hispida (Born et al., 1999), Pacific brant (Branta bernicl nigricans), and Canada geese (B. canadensis) increased as a helicopter or fixed-wing aircraft more directly approached groups of these animals (Ward et al., 1999). Bald eagles (Haliaeetus leucocephalus) perched on trees alongside a river were also more likely to flee from a paddle raft when their perches were closer to the river or were closer to the ground (Steidl and Anthony, 1996). Response to Predator As discussed earlier, evidence suggests that at least some marine mammals have the ability to acoustically identify potential predators. For example, harbor seals that reside in the coastal waters off British Columbia are frequently targeted by certain groups of killer whales, but not others. The seals discriminate between the calls of threatening and non-threatening killer whales (Deecke et al., 2002), a capability that should increase survivorship while reducing the energy required for attending to and responding to all killer whale calls. The occurrence of masking or hearing impairment provides a means by which marine mammals may be prevented from responding to the acoustic cues produced by their predators. Whether or not this is a E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 possibility depends on the duration of the masking/hearing impairment and the likelihood of encountering a predator during the time that predator cues are impeded. Alteration of Diving or Movement Changes in dive behavior can vary widely. They may consist of increased or decreased dive times and surface intervals as well as changes in the rates of ascent and descent during a dive (e.g., Frankel and Clark, 2000; Ng and Leung, 2003; Nowacek et al.; 2004; Goldbogen et al., 2013a, 2013b). Variations in dive behavior may reflect interruptions in biologically significant activities (e.g., foraging) or they may be of little biological significance. Variations in dive behavior may also expose an animal to potentially harmful conditions (e.g., increasing the chance of ship-strike) or may serve as an avoidance response that enhances survivorship. The impact of a variation in diving resulting from an acoustic exposure depends on what the animal is doing at the time of the exposure and the type and magnitude of the response. Nowacek et al. (2004) reported disruptions of dive behaviors in foraging North Atlantic right whales when exposed to an alerting stimulus, an action, they noted, that could lead to an increased likelihood of ship strike. However, the whales did not respond to playbacks of either right whale social sounds or vessel noise, highlighting the importance of the sound characteristics in producing a behavioral reaction. Conversely, Indo-Pacific humpback dolphins have been observed to dive for longer periods of time in areas where vessels were present and/or approaching (Ng and Leung, 2003). In both of these studies, the influence of the sound exposure cannot be decoupled from the physical presence of a surface vessel, thus complicating interpretations of the relative contribution of each stimulus to the response. Indeed, the presence of surface vessels, their approach, and speed of approach, seemed to be significant factors in the response of the Indo-Pacific humpback dolphins (Ng and Leung, 2003). Low-frequency signals of the Acoustic Thermometry of Ocean Climate (ATOC) sound source were not found to affect dive times of humpback whales in Hawaiian waters (Frankel and Clark, 2000) or to overtly affect elephant seal dives (Costa et al., 2003). They did, however, produce subtle effects that varied in direction and degree among the individual seals, illustrating the equivocal nature of behavioral effects and consequent difficulty in defining and predicting VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 them. Lastly, as noted previously, DeRuiter et al. (2013) noted that distance from a sound source may moderate marine mammal reactions in their study of Cuvier’s beaked whales, which showed the whales swimming rapidly and silently away when a sonar signal was 3.4–9.5 km away while showing no such reaction to the same signal when the signal was 118 km away even though the received levels were similar. Foraging Disruption of feeding behavior can be difficult to correlate with anthropogenic sound exposure, so it is usually inferred by observed displacement from known foraging areas, the appearance of secondary indicators (e.g., bubble nets or sediment plumes), or changes in dive behavior. As for other types of behavioral response, the frequency, duration, and temporal pattern of signal presentation, as well as differences in species sensitivity, are likely contributing factors to differences in response in any given circumstance (e.g., Croll et al., 2001; Harris et al., 2017; Madsen et al., 2006a; Nowacek et al.; 2004; Yazvenko et al., 2007). A determination of whether foraging disruptions incur fitness consequences would require information on or estimates of the energetic requirements of the affected individuals and the relationship between prey availability, foraging effort and success, and the life history stage of the animal. Noise from seismic surveys was not found to impact the feeding behavior in western grey whales off the coast of Russia (Yazvenko et al., 2007). Visual tracking, passive acoustic monitoring, and movement recording tags were used to quantify sperm whale behavior prior to, during, and following exposure to air gun arrays at received levels in the range 140–160 dB at distances of 7–13 km, following a phase-in of sound intensity and full array exposures at 1– 13 km (Madsen et al., 2006a; Miller et al., 2009). Sperm whales did not exhibit horizontal avoidance behavior at the surface. However, foraging behavior may have been affected. The sperm whales exhibited 19 percent less vocal (buzz) rate during full exposure relative to post exposure, and the whale that was approached most closely had an extended resting period and did not resume foraging until the air guns had ceased firing. The remaining whales continued to execute foraging dives throughout exposure; however, swimming movements during foraging dives were six percent lower during exposure than control periods (Miller et al., 2009). These data raise concerns that PO 00000 Frm 00033 Fmt 4701 Sfmt 4702 33945 air gun surveys may impact foraging behavior in sperm whales, although more data are required to understand whether the differences were due to exposure or natural variation in sperm whale behavior (Miller et al., 2009). Balaenopterid whales exposed to moderate low-frequency signals similar to the ATOC sound source demonstrated no variation in foraging activity (Croll et al., 2001), whereas five out of six North Atlantic right whales exposed to an acoustic alarm interrupted their foraging dives (Nowacek et al., 2004). Although the received SPLs were similar in the latter two studies, the frequency, duration, and temporal pattern of signal presentation were different. These factors, as well as differences in species sensitivity, are likely contributing factors to the differential response. Blue whales exposed to mid-frequency sonar in the Southern California Bight were less likely to produce low frequency calls usually associated with feeding behavior (Melco´n et al., 2012). However, Melco´n et al. (2012) were unable to determine if suppression of low frequency calls reflected a change in their feeding performance or abandonment of foraging behavior and indicated that implications of the documented responses are unknown. Further, it is not known whether the lower rates of calling actually indicated a reduction in feeding behavior or social contact since the study used data from remotely deployed, passive acoustic monitoring buoys. In contrast, blue whales increased their likelihood of calling when ship noise was present, and decreased their likelihood of calling in the presence of explosive noise, although this result was not statistically significant (Melco´n et al., 2012). Additionally, the likelihood of an animal calling decreased with the increased received level of midfrequency sonar, beginning at a SPL of approximately 110–120 dB re: 1 mPa (Melco´n et al., 2012). Results from behavioral response studies in Southern California waters indicated that, in some cases and at low received levels, tagged blue whales responded to midfrequency sonar but that those responses were were generally brief, of low to moderate severity, and highly dependent on exposure context (Southall et al., 2011; Southall et al., 2012b, Southall et al., 2019b). Information on or estimates of the energetic requirements of the individuals and the relationship between prey availability, foraging effort and success, and the life history stage of the animal will help better inform a E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33946 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules determination of whether foraging disruptions incur fitness consequences. Surface feeding blue whales did not show a change in behavior in response to mid-frequency simulated and real sonar sources with received levels between 90 and 179 dB re: 1 mPa, but deep feeding and non-feeding whales showed temporary reactions including cessation of feeding, reduced initiation of deep foraging dives, generalized avoidance responses, and changes to dive behavior. The behavioral responses they observed were generally brief, of low to moderate severity, and highly dependent on exposure context (behavioral state, source-to-whale horizontal range, and prey availability) (DeRuiter et al., 2017; Goldbogen et al., 2013b; Sivle et al., 2015). Goldbogen et al. (2013b) indicate that disruption of feeding and displacement could impact individual fitness and health. However, for this to be true, we would have to assume that an individual whale could not compensate for this lost feeding opportunity by either immediately feeding at another location, by feeding shortly after cessation of acoustic exposure, or by feeding at a later time. There is no indication this is the case, particularly since unconsumed prey would likely still be available in the environment in most cases following the cessation of acoustic exposure. Similarly, while the rates of foraging lunges decrease in humpback whales due to sonar exposure, there was variability in the response across individuals, with one animal ceasing to forage completely and another animal starting to forage during the exposure (Sivle et al., 2016). In addition, almost half of the animals that exhibited avoidance behavior were foraging before the exposure but the others were not; the animals that exhibited avoidance behavior while not feeding responded at a slightly lower received level and greater distance than those that were feeding (Wensveen et al., 2017). These findings indicate that the behavioral state of the animal plays a role in the type and severity of a behavioral response. In fact, when the prey field was mapped and used as a covariate in similar models looking for a response in the same blue whales, the response in deep-feeding behavior by blue whales was even more apparent, reinforcing the need for contextual variables to be included when assessing behavioral responses (Friedlaender et al., 2016). Breathing Respiration naturally varies with different behaviors and variations in respiration rate as a function of acoustic exposure can be expected to co-occur VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 with other behavioral reactions, such as a flight response or an alteration in diving. However, respiration rates in and of themselves may be representative of annoyance or an acute stress response. Mean exhalation rates of gray whales at rest and while diving were found to be unaffected by seismic surveys conducted adjacent to the whale feeding grounds (Gailey et al., 2007). Studies with captive harbor porpoises showed increased respiration rates upon introduction of acoustic alarms (Kastelein et al., 2001; Kastelein et al., 2006a) and emissions for underwater data transmission (Kastelein et al., 2005). However, exposure of the same acoustic alarm to a striped dolphin under the same conditions did not elicit a response (Kastelein et al., 2006a), again highlighting the importance in understanding species differences in the tolerance of underwater noise when determining the potential for impacts resulting from anthropogenic sound exposure. Social Relationships Social interactions between mammals can be affected by noise via the disruption of communication signals or by the displacement of individuals. Disruption of social relationships therefore depends on the disruption of other behaviors (e.g., avoidance, masking, etc.). Sperm whales responded to military sonar, apparently from a submarine, by dispersing from social aggregations, moving away from the sound source, remaining relatively silent, and becoming difficult to approach (Watkins et al., 1985). In contrast, sperm whales in the Mediterranean that were exposed to submarine sonar continued calling (J. Gordon pers. comm. cited in Richardson et al., 1995). Long-finned pilot whales exposed to three types of disturbance— playbacks of killer whale sounds, naval sonar exposure, and tagging—resulted in increased group sizes (Visser et al., 2016). In response to sonar, pilot whales also spent more time at the surface with other members of the group (Visser et al., 2016). However, social disruptions must be considered in context of the relationships that are affected. While some disruptions may not have deleterious effects, others, such as longterm or repeated disruptions of mother/ calf pairs or interruption of mating behaviors, have the potential to affect the growth and survival or reproductive effort/success of individuals. Vocalizations (Also See Auditory Masking Section) Vocal changes in response to anthropogenic noise can occur across PO 00000 Frm 00034 Fmt 4701 Sfmt 4702 the repertoire of sound production modes used by marine mammals, such as whistling, echolocation click production, calling, and singing. Changes in vocalization behavior that may result in response to anthropogenic noise can occur for any of these modes and may result from a need to compete with an increase in background noise or may reflect an increased vigilance or a startle response. For example, in the presence of potentially masking signals (low-frequency active sonar), humpback whales have been observed to increase the length of their songs (Miller et al., 2000; Fristrup et al., 2003). A similar compensatory effect for the presence of low-frequency vessel noise has been suggested for right whales; right whales have been observed to shift the frequency content of their calls upward while reducing the rate of calling in areas of increased anthropogenic noise (Parks et al., 2007; Roland et al., 2012). Killer whales off the northwestern coast of the United States have been observed to increase the duration of primary calls once a threshold in observing vessel density (e.g., whale watching) was reached, which has been suggested as a response to increased masking noise produced by the vessels (Foote et al., 2004; NOAA, 2014b). In contrast, both sperm and pilot whales potentially ceased sound production during the Heard Island feasibility test (Bowles et al., 1994), although it cannot be absolutely determined whether the inability to acoustically detect the animals was due to the cessation of sound production or the displacement of animals from the area. Cerchio et al. (2014) used passive acoustic monitoring to document the presence of singing humpback whales off the coast of northern Angola and to opportunistically test for the effect of seismic survey activity on the number of singing whales. Two recording units were deployed between March and December 2008 in the offshore environment; numbers of singers were counted every hour. Generalized Additive Mixed Models were used to assess the effect of survey day (seasonality), hour (diel variation), moon phase, and received levels of noise (measured from a single pulse during each ten-minute sampled period) on singer number. The number of singers significantly decreased with increasing received level of noise, suggesting that humpback whale communication was disrupted to some extent by the survey activity. Castellote et al. (2012) reported acoustic and behavioral changes by fin whales in response to shipping and air gun noise. Acoustic features of fin E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules whale song notes recorded in the Mediterranean Sea and northeast Atlantic Ocean were compared for areas with different shipping noise levels and traffic intensities and during an air gun survey. During the first 72 hours of the survey, a steady decrease in song received levels and bearings to singers indicated that whales moved away from the acoustic source and out of a Navy study area. This displacement persisted for a time period well beyond the 10day duration of air gun activity, providing evidence that fin whales may avoid an area for an extended period in the presence of increased noise. The authors hypothesize that fin whale acoustic communication is modified to compensate for increased background noise and that a sensitization process may play a role in the observed temporary displacement. Seismic pulses at average received levels of 131 dB re: 1 micropascal squared per second (mPa2-s) caused blue whales to increase call production (Di Iorio and Clark, 2010). In contrast, McDonald et al. (1995) tracked a blue whale with seafloor seismometers and reported that it stopped vocalizing and changed its travel direction at a range of 10 km from the seismic vessel (estimated received level 143 dB re: 1 mPa peak-to-peak). Blackwell et al. (2013) found that bowhead whale call rates dropped significantly at onset of air gun use at sites with a median distance of 41–45 km from the survey. Blackwell et al. (2015) expanded this analysis to show that whales actually increased calling rates as soon as air gun signals were detectable before ultimately decreasing calling rates at higher received levels (i.e., 10-minute cumulative sound exposure level (cSEL) of ∼127 dB). Overall, these results suggest that bowhead whales may adjust their vocal output in an effort to compensate for noise before ceasing vocalization effort and ultimately deflecting from the acoustic source (Blackwell et al., 2013, 2015). Captive bottlenose dolphins sometimes vocalized after an exposure to impulse sound from a seismic water gun (Finneran et al., 2010a). These studies demonstrate that even low levels of noise received far from the noise source can induce changes in vocalization and/ or behavioral responses. Avoidance Avoidance is the displacement of an individual from an area or migration path as a result of the presence of a sound or other stressors. Richardson et al. (1995) noted that avoidance reactions are the most obvious manifestations of disturbance in marine mammals. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Avoidance is qualitatively different from the flight response, but also differs in the magnitude of the response (i.e., directed movement, rate of travel, etc.). Oftentimes avoidance is temporary, and animals return to the area once the noise has ceased. Acute avoidance responses have been observed in captive porpoises and pinnipeds exposed to a number of different sound sources (Kastelein et al., 2001; Finneran et al., 2003; Kastelein et al., 2006a; Kastelein et al., 2006b). Short-term avoidance of seismic surveys, low frequency emissions, and acoustic deterrents have also been noted in wild populations of odontocetes (Bowles et al., 1994; Goold, 1996; 1998; Stone et al., 2000; Morton and Symonds, 2002) and to some extent in mysticetes (Gailey et al., 2007). Longerterm displacement is possible, however, which may lead to changes in abundance or distribution patterns of the affected species in the affected region if habituation to the presence of the sound does not occur (e.g., Blackwell et al., 2004; Bejder et al., 2006; Teilmann et al., 2006). Longer term or repetitive/chronic displacement for some dolphin groups and for manatees has been suggested to be due to the presence of chronic vessel noise (Haviland-Howell et al., 2007; MiksisOlds et al., 2007). Gray whales have been reported deflecting from customary migratory paths in order to avoid noise from air gun surveys (Malme et al., 1984). Humpback whales showed avoidance behavior in the presence of an active air gun array during observational studies and controlled exposure experiments in western Australia (McCauley et al., 2000a). As discussed earlier, Forney et al. (2017) detailed the potential effects of noise on marine mammal populations with high site fidelity, including displacement and auditory masking, noting that a lack of observed response does not imply absence of fitness costs and that apparent tolerance of disturbance may have population-level impacts that are less obvious and difficult to document. Avoidance of overlap between disturbing noise and areas and/or times of particular importance for sensitive species may be critical to avoiding population-level impacts because (particularly for animals with high site fidelity) there may be a strong motivation to remain in the area despite negative impacts. Forney et al. (2017) stated that, for these animals, remaining in a disturbed area may reflect a lack of alternatives rather than a lack of effects. The authors discuss several case studies, including western Pacific gray whales, which are PO 00000 Frm 00035 Fmt 4701 Sfmt 4702 33947 a small population of mysticetes believed to be adversely affected by oil and gas development off Sakhalin Island, Russia (Weller et al., 2002; Reeves et al., 2005). Western gray whales display a high degree of interannual site fidelity to the area for foraging purposes, and observations in the area during air gun surveys have shown the potential for harm caused by displacement from such an important area (Weller et al., 2006; Johnson et al., 2007). Forney et al. (2017) also discuss beaked whales, noting that anthropogenic effects in areas where they are resident could cause severe biological consequences, in part because displacement may adversely affect foraging rates, reproduction, or health, while an overriding instinct to remain could lead to more severe acute effects. In 1998, the Navy conducted a Low Frequency Sonar Scientific Research Program (LFS SRP) specifically to study behavioral responses of several species of marine mammals to exposure to LF sound, including one phase that focused on the behavior of gray whales to low frequency sound signals. The objective of this phase of the LFS SRP was to determine whether migrating gray whales respond more strongly to received levels, sound gradient, or distance from the source, and to compare whale avoidance responses to an LF source in the center of the migration corridor versus in the offshore portion of the migration corridor. A single source was used to broadcast LFAS sounds at received levels of 170– 178 dB re: 1 mPa. The Navy reported that the whales showed some avoidance responses when the source was moored one mile (1.8 km) offshore, and located within the migration path, but the whales returned to their migration path when they were a few kilometers beyond the source. When the source was moored two miles (3.7 km) offshore, responses were much less, even when the source level was increased to achieve the same received levels in the middle of the migration corridor as whales received when the source was located within the migration corridor (Clark et al., 1999). In addition, the researchers noted that the offshore whales did not seem to avoid the louder offshore source. Also during the LFS SRP, researchers sighted numerous odontocete and pinniped species in the vicinity of the sound exposure tests with LFA sonar. The MF and HF hearing specialists present in California and Hawaii showed no immediately obvious responses or changes in sighting rates as a function of source conditions. Consequently, the researchers E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33948 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules concluded that none of these species had any obvious behavioral reaction to LFA sonar signals at received levels similar to those that produced only minor short-term behavioral responses in the baleen whales (i.e., LF hearing specialists). Thus, for odontocetes, the chances of injury and/or significant behavioral responses to LFA sonar would be low given the MF/HF specialists’ observed lack of response to LFA sounds during the LFS SRP and due to the MF/HF frequencies to which these animals are adapted to hear (Clark and Southall, 2009). Maybaum (1993) conducted sound playback experiments to assess the effects of MFAS on humpback whales in Hawaiian waters. Specifically, she exposed focal pods to sounds of a 3.3kHz sonar pulse, a sonar frequency sweep from 3.1 to 3.6 kHz, and a control (blank) tape while monitoring behavior, movement, and underwater vocalizations. The two types of sonar signals differed in their effects on the humpback whales, but both resulted in avoidance behavior. The whales responded to the pulse by increasing their distance from the sound source and responded to the frequency sweep by increasing their swimming speeds and track linearity. In the Caribbean, sperm whales avoided exposure to midfrequency submarine sonar pulses, in the range of 1,000 Hz to 10,000 Hz (IWC, 2005). Kvadsheim et al. (2007) conducted a controlled exposure experiment in which killer whales fitted with D-tags were exposed to mid-frequency active sonar (Source A: A 1.0 second upsweep 209 dB at 1–2 kHz every 10 seconds for 10 minutes; Source B: with a 1.0 second upsweep 197 dB at 6–7 kHz every 10 seconds for 10 minutes). When exposed to Source A, a tagged whale and the group it was traveling with did not appear to avoid the source. When exposed to Source B, the tagged whales along with other whales that had been carousel feeding, where killer whales cooperatively herd fish schools into a tight ball towards the surface and feed on the fish which have been stunned by tailslaps, and subsurface feeding (Simila, 1997) ceased feeding during the approach of the sonar and moved rapidly away from the source. When exposed to Source B, Kvadsheim et al. (2007) reported that a tagged killer whale seemed to try to avoid further exposure to the sound field by the following behaviors: Immediately swimming away (horizontally) from the source of the sound; engaging in a series of erratic and frequently deep dives that seemed to take it below the sound field; or swimming away while engaged in a VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 series of erratic and frequently deep dives. Although the sample sizes in this study are too small to support statistical analysis, the behavioral responses of the killer whales were consistent with the results of other studies. Southall et al. (2007) reviewed the available literature on marine mammal hearing and physiological and behavioral responses to human-made sound with the goal of proposing exposure criteria for certain effects. This peer-reviewed compilation of literature is very valuable, though Southall et al. (2007) note that not all data are equal and some have poor statistical power, insufficient controls, and/or limited information on received levels, background noise, and other potentially important contextual variables. Such data were reviewed and sometimes used for qualitative illustration, but no quantitative criteria were recommended for behavioral responses. All of the studies considered, however, contain an estimate of the received sound level when the animal exhibited the indicated response. In the Southall et al. (2007) publication, for the purposes of analyzing responses of marine mammals to anthropogenic sound and developing criteria, the authors differentiate between single pulse sounds, multiple pulse sounds, and non-pulse sounds. LFAS/MFAS/HFAS are considered nonpulse sounds. Southall et al. (2007) summarize the studies associated with low-frequency, mid-frequency, and high-frequency cetacean and pinniped responses to non-pulse sounds, based strictly on received level, in Appendix C of their article (referenced and summarized in the following paragraphs). The studies that address responses of low-frequency cetaceans to non-pulse sounds include data gathered in the field and related to several types of sound sources (of varying similarity to active sonar) including: Vessel noise, drilling and machinery playback, lowfrequency M-sequences (sine wave with multiple phase reversals) playback, tactical low-frequency active sonar playback, drill ships, ATOC source, and non-pulse playbacks. These studies generally indicate no (or very limited) responses to received levels in the 90 to 120 dB re: 1 mPa range and an increasing likelihood of avoidance and other behavioral effects in the 120 to 160 dB re: 1 mPa range. As mentioned earlier, though, contextual variables play a very important role in the reported responses and the severity of effects are not linear when compared to received level. Also, few of the laboratory or field datasets had common conditions, behavioral PO 00000 Frm 00036 Fmt 4701 Sfmt 4702 contexts, or sound sources, so it is not surprising that responses differ. The studies that address responses of mid-frequency cetaceans to non-pulse sounds include data gathered both in the field and the laboratory and related to several different sound sources (of varying similarity to active sonar) including: Pingers, drilling playbacks, ship and ice-breaking noise, vessel noise, Acoustic Harassment Devices (AHDs), Acoustic Deterrent Devices (ADDs), MFAS, and non-pulse bands and tones. Southall et al. (2007) were unable to come to a clear conclusion regarding the results of these studies. In some cases, animals in the field showed significant responses to received levels between 90 and 120 dB re: 1 mPa, while in other cases these responses were not seen in the 120 to 150 dB re: 1 mPa range. The disparity in results was likely due to contextual variation and the differences between the results in the field and laboratory data (animals typically responded at lower levels in the field). The studies that address responses of high-frequency cetaceans to non-pulse sounds include data gathered both in the field and the laboratory and related to several different sound sources (of varying similarity to active sonar) including: Pingers, AHDs, and various laboratory non-pulse sounds. All of these data were collected from harbor porpoises. Southall et al. (2007) concluded that the existing data indicate that harbor porpoises are likely sensitive to a wide range of anthropogenic sounds at low received levels (∼90 to 120 dB re: 1 mPa), at least for initial exposures. All recorded exposures above 140 dB re: 1 mPa induced profound and sustained avoidance behavior in wild harbor porpoises (Southall et al., 2007). Rapid habituation was noted in some but not all studies. There are no data to indicate whether other high frequency cetaceans are as sensitive to anthropogenic sound as harbor porpoises. The studies that address the responses of pinnipeds in water to non-impulsive sounds include data gathered both in the field and the laboratory and related to several different sound sources including: AHDs, ATOC, various nonpulse sounds used in underwater data communication, underwater drilling, and construction noise. Few studies existed with enough information to include them in the analysis. The limited data suggested that exposures to non-pulse sounds between 90 and 140 dB re: 1 mPa generally do not result in strong behavioral responses in pinnipeds in water, but no data exist at higher received levels. E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules In 2007, the first in a series of behavioral response studies (BRS) on deep diving odontocetes conducted by NMFS, Navy, and other scientists showed one Blainville’s beaked whale responding to an MFAS playback. Tyack et al. (2011) indicates that the playback began when the tagged beaked whale was vocalizing at depth (at the deepest part of a typical feeding dive), following a previous control with no sound exposure. The whale appeared to stop clicking significantly earlier than usual, when exposed to MF signals in the 130– 140 dB (rms) received level range. After a few more minutes of the playback, when the received level reached a maximum of 140–150 dB, the whale ascended on the slow side of normal ascent rates with a longer than normal ascent, at which point the exposure was terminated. The results are from a single experiment and a greater sample size is needed before robust and definitive conclusions can be drawn. Tyack et al. (2011) also indicates that Blainville’s beaked whales appear to be sensitive to noise at levels well below expected TTS (∼160 dB re: 1m Pa). This sensitivity was manifested by an adaptive movement away from a sound source. This response was observed irrespective of whether the signal transmitted was within the band width of MFAS, which suggests that beaked whales may not respond to the specific sound signatures. Instead, they may be sensitive to any pulsed sound from a point source in this frequency range of the MFAS transmission. The response to such stimuli appears to involve the beaked whale increasing the distance between it and the sound source. Overall the results from the 2007–2008 study showed a change in diving behavior of the Blainville’s beaked whale to playback of MFAS and predator sounds (Boyd et al., 2008; Southall et al., 2009; Tyack et al., 2011). Stimpert et al. (2014) tagged a Baird’s beaked whale, which was subsequently exposed to simulated MFAS. Received levels of sonar on the tag increased to a maximum of 138 dB re: 1 mPa, which occurred during the first exposure dive. Some sonar received levels could not be measured due to flow noise and surface noise on the tag. Reaction to mid-frequency sounds included premature cessation of clicking and termination of a foraging dive, and a slower ascent rate to the surface. Results from a similar behavioral response study in southern California waters were presented for the 2010–2011 field season (Southall et al., 2011; DeRuiter et al., 2013b). DeRuiter et al. (2013b) presented results from two Cuvier’s beaked whales that were tagged VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 and exposed to simulated MFAS during the 2010 and 2011 field seasons of the southern California behavioral response study. The 2011 whale was also incidentally exposed to MFAS from a distant naval exercise. Received levels from the MFAS signals from the controlled and incidental exposures were calculated as 84–144 and 78–106 dB re: 1 mPa rms, respectively. Both whales showed responses to the controlled exposures, ranging from initial orientation changes to avoidance responses characterized by energetic fluking and swimming away from the source. However, the authors did not detect similar responses to incidental exposure to distant naval sonar exercises at comparable received levels, indicating that context of the exposures (e.g., source proximity, controlled source ramp-up) may have been a significant factor. Specifically, this result suggests that caution is needed when using marine mammal response data collected from smaller, nearer sound sources to predict at what received levels animals may respond to larger sound sources that are significantly farther away—as the distance of the source appears to be an important contextual variable and animals may be less responsive to sources at notably greater distances. Cuvier’s beaked whale responses suggested particular sensitivity to sound exposure as consistent with results for Blainville’s beaked whale. Similarly, beaked whales exposed to sonar during British training exercises stopped foraging (DSTL, 2007), and preliminary results of controlled playback of sonar may indicate feeding/foraging disruption of killer whales and sperm whales (Miller et al., 2011). In the 2007–2008 Bahamas study, playback sounds of a potential predator—a killer whale—resulted in a similar but more pronounced reaction, which included longer inter-dive intervals and a sustained straight-line departure of more than 20 km from the area (Boyd et al., 2008; Southall et al., 2009; Tyack et al., 2011). The authors noted, however, that the magnified reaction to the predator sounds could represent a cumulative effect of exposure to the two sound types since killer whale playback began approximately two hours after MF source playback. Pilot whales and killer whales off Norway also exhibited horizontal avoidance of a transducer with outputs in the mid-frequency range (signals in the 1–2 kHz and 6–7 kHz ranges) (Miller et al., 2011). Additionally, separation of a calf from its group during exposure to MFAS PO 00000 Frm 00037 Fmt 4701 Sfmt 4702 33949 playback was observed on one occasion (Miller et al., 2011, 2012). Miller et al. (2012) noted that this single observed mother-calf separation was unusual for several reasons, including the fact that the experiment was conducted in an unusually narrow fjord roughly one km wide and that the sonar exposure was started unusually close to the pod including the calf. Both of these factors could have contributed to calf separation. In contrast, preliminary analyses suggest that none of the pilot whales or false killer whales in the Bahamas showed an avoidance response to controlled exposure playbacks (Southall et al., 2009). In the 2010 BRS study, researchers again used controlled exposure experiments to carefully measure behavioral responses of individual animals to sound exposures of MFAS and pseudo-random noise. For each sound type, some exposures were conducted when animals were in a surface feeding (approximately 164 ft (50 m) or less) and/or socializing behavioral state and others while animals were in a deep feeding (greater than 164 ft (50 m)) and/or traveling mode. The researchers conducted the largest number of controlled exposure experiments on blue whales (n=19) and of these, 11 controlled exposure experiments involved exposure to the MFAS sound type. For the majority of controlled exposure experiment transmissions of either sound type, they noted few obvious behavioral responses detected either by the visual observers or on initial inspection of the tag data. The researchers observed that throughout the controlled exposure experiment transmissions, up to the highest received sound level (absolute RMS value approximately 160 dB re: 1 mPa with signal-to-noise ratio values over 60 dB), two blue whales continued surface feeding behavior and remained at a range of around 3,820 ft (1,000 m) from the sound source (Southall et al., 2011). In contrast, another blue whale (later in the day and greater than 11.5 mi (18.5 km; 10 nmi) from the first controlled exposure experiment location) exposed to the same stimulus (MFA) while engaged in a deep feeding/ travel state exhibited a different response. In that case, the blue whale responded almost immediately following the start of sound transmissions when received sounds were just above ambient background levels (Southall et al., 2011). The authors note that this kind of temporary avoidance behavior was not evident in any of the nine controlled exposure experiments involving blue whales E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33950 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules engaged in surface feeding or social behaviors, but was observed in three of the ten controlled exposure experiments for blue whales in deep feeding/travel behavioral modes (one involving MFA sonar; two involving pseudo-random noise) (Southall et al., 2011). The results of this study, as well as the results of the DeRuiter et al. (2013) study of Cuvier’s beaked whales discussed above, further illustrate the importance of behavioral context in understanding and predicting behavioral responses. Through analysis of the behavioral response studies, a preliminary overarching effect of greater sensitivity to all anthropogenic exposures was seen in beaked whales compared to the other odontocetes studied (Southall et al., 2009). Therefore, recent studies have focused specifically on beaked whale responses to active sonar transmissions or controlled exposure playback of simulated sonar on various military ranges (Defence Science and Technology Laboratory, 2007; Claridge and Durban, 2009; Moretti et al., 2009; McCarthy et al., 2011; Miller et al., 2012; Southall et al., 2011, 2012a, 2012b, 2013, 2014; Tyack et al., 2011). In the Bahamas, Blainville’s beaked whales located on the instrumented range will move off-range during sonar use and return only after the sonar transmissions have stopped, sometimes taking several days to do so (Claridge and Durban 2009; Moretti et al., 2009; McCarthy et al., 2011; Tyack et al., 2011). Moretti et al. (2014) used recordings from seafloor-mounted hydrophones at the Atlantic Undersea Test and Evaluation Center (AUTEC) to analyze the probability of Blainsville’s beaked whale dives before, during, and after Navy sonar exercises. Southall et al. (2016) indicates that results from Tyack et al. (2011), Miller et al. (2015), Stimpert et al. (2014), and DeRuiter et al. (2013) beaked whale studies demonstrate clear, strong, and pronounced but varied behavioral changes including avoidance with associated energetic swimming and cessation of individual foraging dives at quite low received levels (∼100 to 135 dB re: 1 Pa) for exposures to simulated or active MF military sonars (1–8 kHz) with sound sources approximately 2–5 km away. Similar responses by beaked whales to sonar have been documented by Stimpert et al., 2014, Falcone et al., 2017, DiMarzio et al., 2018, and Joyce et al., 2019. However, there are a number of variables influencing response or non-response including source distance (close vs. far), received sound levels, and other contextual variables such as other sound sources (e.g., vessels, etc.) (Manzano-Roth et al., 2016, Falcone et VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 al., 2017, Harris et al., 2018). Wensveen et al. (2019) found northern bottlenose whales to avoid sonar out to distances of 28 km, but these distances are well in line with those observed on Navy ranges (Manzano-Roth et al., 2016; Joyce et al., 2019) where the animals return once the sonar has ceased. Furthermore, beaked whales have also shown response to other non-sonar anthropogenic sounds such as commercial shipping and echosounders (Soto et al., 2006, Pirotta et al., 2012, Cholewiak et al., 2017). Pirotta et al. (2012) documented broadband ship noise causing a significant change in beaked whale behavior up to at least 5.2 km away from the vessel. Even though beaked whales appear to be sensitive to anthropogenic sounds, the level of response at the population level does not appear to be significant based on over a decade of research at two heavily used Navy training areas in the Pacific (Falcone et al., 2012, Schorr et al., 2014, DiMarzio et al., 2018, Schorr et al., 2019). With the exception of seasonal patterns, DiMarzio et al. (2018) did not detect any changes in annual Cuvier’s beaked whale abundance estimates in Southern California derived from passive acoustic echolocation detections over nine years (2010–2018). Similar results for Blainville’s beaked whales abundance estimates over several years was documented in Hawaii (Henderson et al., 2016;, DiMarzio et al., 2018). Visually, there have been documented repeated sightings in southern California of the same individual Cuvier’s beaked whales over 10 years, sightings of mother-calf pairs, and recently sightings of the same mothers with their second calf (Falcone et al., 2012; Schorr et al., 2014; Schorr et al., 2019; Schorr, unpublished data). Baleen whales have shown a variety of responses to impulse sound sources, including avoidance, reduced surface intervals, altered swimming behavior, and changes in vocalization rates (Richardson et al., 1995; Gordon et al., 2003; Southall, 2007). While most bowhead whales did not show active avoidance until within 8 km of seismic vessels (Richardson et al., 1995), some whales avoided vessels by more than 20 km at received levels as low as 120 dB re: 1 mPa rms. Additionally, Malme et al. (1988) observed clear changes in diving and respiration patterns in bowheads at ranges up to 73 km from seismic vessels, with received levels as low as 125 dB re: 1 mPa. Gray whales migrating along the United States West Coast showed avoidance responses to seismic vessels by 10 percent of animals at 164 dB re: 1 mPa, and by 90 percent of animals at PO 00000 Frm 00038 Fmt 4701 Sfmt 4702 190 dB re: 1 mPa, with similar results for whales in the Bering Sea (Malme, 1986; 1988). In contrast, noise from seismic surveys was not found to impact feeding behavior or exhalation rates while resting or diving in western gray whales off the coast of Russia (Yazvenko et al., 2007; Gailey et al., 2007). Humpback whales showed avoidance behavior at ranges of five to eight km from a seismic array during observational studies and controlled exposure experiments in western Australia (McCauley, 1998; Todd et al., 1996). Todd et al. (1996) found no clear short-term behavioral responses by foraging humpbacks to explosions associated with construction operations in Newfoundland, but did see a trend of increased rates of net entanglement and a shift to a higher incidence of net entanglement closer to the noise source. The strongest baleen whale response in any behavioral response study was observed in a minke whale in the 3S2 study, which responded at 146 dB re: 1 mPa by strongly avoiding the sound source (Kvadsheim et al., 2017; Sivle et al., 2015). Although the minke whale increased its swim speed, directional movement, and respiration rate, none of these were greater than rates observed in baseline behavior, and its dive behavior remained similar to baseline dives. A minke whale tagged in the Southern California behavioral response study also responded by increasing its directional movement, but maintained its speed and dive patterns, and so did not demonstrate as strong of a response (Kvadsheim et al., 2017). In addition, the 3S2 minke whale demonstrated some of the same avoidance behavior during the controlled ship approach with no sonar, indicating at least some of the response was to the vessel (Kvadsheim et al., 2017). Martin et al. (2015) found that the density of calling minke whales was reduced during periods of Navy training involving sonar relative to the periods before training, and increased again in the days after training was completed. The responses of individual whales could not be assessed, so in this case it is unknown whether the decrease in calling animals indicated that the animals left the range, or simply ceased calling. Similarly, minke whale detections made using Marine Acoustic Recording Instruments off Jacksonville, FL, were reduced or ceased altogether during periods of sonar use (Simeone et al., 2015; U.S. Department of the Navy, 2013b), especially with an increased ping rate (Charif et al., 2015). E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Orientation A shift in an animal’s resting state or an attentional change via an orienting response represent behaviors that would be considered mild disruptions if occurring alone. As previously mentioned, the responses may co-occur with other behaviors; for instance, an animal may initially orient toward a sound source, and then move away from it. Thus, any orienting response should be considered in context of other reactions that may occur. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Continued Pre-Disturbance Behavior and Habituation Under some circumstances, some of the individual marine mammals that are exposed to active sonar transmissions will continue their normal behavioral activities. In other circumstances, individual animals will respond to sonar transmissions at lower received levels and move to avoid additional exposure or exposures at higher received levels (Richardson et al., 1995). It is difficult to distinguish between animals that continue their predisturbance behavior without stress responses, animals that continue their behavior but experience stress responses (that is, animals that cope with disturbance), and animals that habituate to disturbance (that is, they may have experienced low-level stress responses initially, but those responses abated over time). Watkins (1986) reviewed data on the behavioral reactions of fin, humpback, right, and minke whales that were exposed to continuous, broadband low-frequency shipping and industrial noise in Cape Cod Bay. He concluded that underwater sound was the primary cause of behavioral reactions in these species of whales and that the whales responded behaviorally to acoustic stimuli within their respective hearing ranges. Watkins also noted that whales showed the strongest behavioral reactions to sounds in the 15 Hz to 28 kHz range, although negative reactions (avoidance, interruptions in vocalizations, etc.) were generally associated with sounds that were either unexpected, too loud, suddenly louder or different, or perceived as being associated with a potential threat (such as an approaching ship on a collision course). In particular, whales seemed to react negatively when they were within 100 m of the source or when received levels increased suddenly in excess of 12 dB relative to ambient sounds. At other times, the whales ignored the source of the signal and all four species habituated to these sounds. Nevertheless, Watkins concluded that whales ignored most sounds in the background of VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 ambient noise, including sounds from distant human activities even though these sounds may have had considerable energies at frequencies well within the whales’ range of hearing. Further, he noted that of the whales observed, fin whales were the most sensitive of the four species, followed by humpback whales; right whales were the least likely to be disturbed and generally did not react to low-amplitude engine noise. By the end of his period of study, Watkins (1986) concluded that fin and humpback whales had generally habituated to the continuous and broad-band noise of Cape Cod Bay while right whales did not appear to change their response. As mentioned above, animals that habituate to a particular disturbance may have experienced low-level stress responses initially, but those responses abated over time. In most cases, this likely means a lessened immediate potential effect from a disturbance. However, there is cause for concern where the habituation occurs in a potentially more harmful situation. For example, animals may become more vulnerable to vessel strikes once they habituate to vessel traffic (Swingle et al., 1993; Wiley et al., 1995). Aicken et al. (2005) monitored the behavioral responses of marine mammals to a new low-frequency active sonar system used by the British Navy (the United States Navy considers this to be a mid-frequency source as it operates at frequencies greater than 1,000 Hz). During those trials, fin whales, sperm whales, Sowerby’s beaked whales, long-finned pilot whales, Atlantic white-sided dolphins, and common bottlenose dolphins were observed and their vocalizations were recorded. These monitoring studies detected no evidence of behavioral responses that the investigators could attribute to exposure to the lowfrequency active sonar during these trials. Explosive Sources Underwater explosive detonations send a shock wave and sound energy through the water and can release gaseous by-products, create an oscillating bubble, or cause a plume of water to shoot up from the water surface. The shock wave and accompanying noise are of most concern to marine animals. Depending on the intensity of the shock wave and size, location, and depth of the animal, an animal can be injured, killed, suffer non-lethal physical effects, experience hearing related effects with or without behavioral responses, or exhibit temporary behavioral responses or PO 00000 Frm 00039 Fmt 4701 Sfmt 4702 33951 tolerance from hearing the blast sound. Generally, exposures to higher levels of impulse and pressure levels would result in greater impacts to an individual animal. Injuries resulting from a shock wave take place at boundaries between tissues of different densities. Different velocities are imparted to tissues of different densities, and this can lead to their physical disruption. Blast effects are greatest at the gas-liquid interface (Landsberg, 2000). Gas-containing organs, particularly the lungs and gastrointestinal tract, are especially susceptible (Goertner, 1982; Hill, 1978; Yelverton et al., 1973). Intestinal walls can bruise or rupture, with subsequent hemorrhage and escape of gut contents into the body cavity. Less severe gastrointestinal tract injuries include contusions, petechiae (small red or purple spots caused by bleeding in the skin), and slight hemorrhaging (Yelverton et al., 1973). Because the ears are the most sensitive to pressure, they are the organs most sensitive to injury (Ketten, 2000). Sound-related damage associated with sound energy from detonations can be theoretically distinct from injury from the shock wave, particularly farther from the explosion. If a noise is audible to an animal, it has the potential to damage the animal’s hearing by causing decreased sensitivity (Ketten, 1995). Lethal impacts are those that result in immediate death or serious debilitation in or near an intense source and are not, technically, pure acoustic trauma (Ketten, 1995). Sublethal impacts include hearing loss, which is caused by exposures to perceptible sounds. Severe damage (from the shock wave) to the ears includes tympanic membrane rupture, fracture of the ossicles, damage to the cochlea, hemorrhage, and cerebrospinal fluid leakage into the middle ear. Moderate injury implies partial hearing loss due to tympanic membrane rupture and blood in the middle ear. Permanent hearing loss also can occur when the hair cells are damaged by one very loud event, as well as by prolonged exposure to a loud noise or chronic exposure to noise. The level of impact from blasts depends on both an animal’s location and, at outer zones, on its sensitivity to the residual noise (Ketten, 1995). Further Potential Effects of Behavioral Disturbance on Marine Mammal Fitness The different ways that marine mammals respond to sound are sometimes indicators of the ultimate effect that exposure to a given stimulus will have on the well-being (survival, reproduction, etc.) of an animal. There E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33952 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules are few quantitative marine mammal data relating the exposure of marine mammals to sound to effects on reproduction or survival, though data exists for terrestrial species to which we can draw comparisons for marine mammals. Several authors have reported that disturbance stimuli may cause animals to abandon nesting and foraging sites (Sutherland and Crockford, 1993); may cause animals to increase their activity levels and suffer premature deaths or reduced reproductive success when their energy expenditures exceed their energy budgets (Daan et al., 1996; Feare, 1976; Mullner et al., 2004); or may cause animals to experience higher predation rates when they adopt risk-prone foraging or migratory strategies (Frid and Dill, 2002). Each of these studies addressed the consequences of animals shifting from one behavioral state (e.g., resting or foraging) to another behavioral state (e.g., avoidance or escape behavior) because of human disturbance or disturbance stimuli. One consequence of behavioral avoidance results in the altered energetic expenditure of marine mammals because energy is required to move and avoid surface vessels or the sound field associated with active sonar (Frid and Dill, 2002). Most animals can avoid that energetic cost by swimming away at slow speeds or speeds that minimize the cost of transport (MiksisOlds, 2006), as has been demonstrated in Florida manatees (Miksis-Olds, 2006). Those energetic costs increase, however, when animals shift from a resting state, which is designed to conserve an animal’s energy, to an active state that consumes energy the animal would have conserved had it not been disturbed. Marine mammals that have been disturbed by anthropogenic noise and vessel approaches are commonly reported to shift from resting to active behavioral states, which would imply that they incur an energy cost. Morete et al. (2007) reported that undisturbed humpback whale cows that were accompanied by their calves were frequently observed resting while their calves circled them (milling). When vessels approached, the amount of time cows and calves spent resting and milling, respectively, declined significantly. These results are similar to those reported by Scheidat et al. (2004) for the humpback whales they observed off the coast of Ecuador. Constantine and Brunton (2001) reported that bottlenose dolphins in the Bay of Islands, New Zealand engaged in resting behavior just 5 percent of the time when vessels were within 300 m, compared with 83 percent of the time VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 when vessels were not present. However, Heenehan et al. (2016) report that results of a study of the response of Hawaiian spinner dolphins to human disturbance suggest that the key factor is not the sheer presence or magnitude of human activities, but rather the directed interactions and dolphin-focused activities that elicit responses from dolphins at rest. This information again illustrates the importance of context in regard to whether an animal will respond to a stimulus. Miksis-Olds (2006) and Miksis-Olds et al. (2005) reported that Florida manatees in Sarasota Bay, Florida, reduced the amount of time they spent milling and increased the amount of time they spent feeding when background noise levels increased. Although the acute costs of these changes in behavior are not likely to exceed an animal’s ability to compensate, the chronic costs of these behavioral shifts are uncertain. Attention is the cognitive process of selectively concentrating on one aspect of an animal’s environment while ignoring other things (Posner, 1994). Because animals (including humans) have limited cognitive resources, there is a limit to how much sensory information they can process at any time. The phenomenon called ‘‘attentional capture’’ occurs when a stimulus (usually a stimulus that an animal is not concentrating on or attending to) ‘‘captures’’ an animal’s attention. This shift in attention can occur consciously or subconsciously (for example, when an animal hears sounds that it associates with the approach of a predator) and the shift in attention can be sudden (Dukas, 2002; van Rij, 2007). Once a stimulus has captured an animal’s attention, the animal can respond by ignoring the stimulus, assuming a ‘‘watch and wait’’ posture, or treat the stimulus as a disturbance and respond accordingly, which includes scanning for the source of the stimulus or ‘‘vigilance’’ (Cowlishaw et al., 2004). Vigilance is normally an adaptive behavior that helps animals determine the presence or absence of predators, assess their distance from conspecifics, or to attend cues from prey (Bednekoff and Lima, 1998; Treves, 2000). Despite those benefits, however, vigilance has a cost of time; when animals focus their attention on specific environmental cues, they are not attending to other activities such as foraging or resting. These effects have generally not been demonstrated for marine mammals, but studies involving fish and terrestrial animals have shown that increased vigilance may substantially reduce feeding rates (Saino, 1994; Beauchamp PO 00000 Frm 00040 Fmt 4701 Sfmt 4702 and Livoreil, 1997; Fritz et al., 2002; Purser and Radford, 2011). Animals will spend more time being vigilant, which may translate to less time foraging or resting, when disturbance stimuli approach them more directly, remain at closer distances, have a greater group size (e.g., multiple surface vessels), or when they co-occur with times that an animal perceives increased risk (e.g., when they are giving birth or accompanied by a calf). An example of this concept with terrestrial species involved bighorn sheep and Dall’s sheep, which dedicated more time being vigilant, and less time resting or foraging, when aircraft made direct approaches over them (Frid, 2001; Stockwell et al., 1991). Vigilance has also been documented in pinnipeds at haul-out sites where resting may be disturbed when seals become alerted and/or flush into the water due to a variety of disturbances, which may be anthropogenic (noise and/or visual stimuli) or due to other natural causes such as other pinnipeds (Richardson et al., 1995; Southall et al., 2007; VanBlaricom, 2010; and Lozano and Hente, 2014). Chronic disturbance can cause population declines through reduction of fitness (e.g., decline in body condition) and subsequent reduction in reproductive success, survival, or both (e.g., Harrington and Veitch, 1992; Daan et al., 1996; Bradshaw et al., 1998). For example, Madsen (1994) reported that pink-footed geese (Anser brachyrhynchus) in undisturbed habitat gained body mass and had about a 46 percent reproductive success rate compared with geese in disturbed habitat (being consistently scared off the fields on which they were foraging) which did not gain mass and had a 17 percent reproductive success rate. Similar reductions in reproductive success have been reported for mule deer (Odocoileus hemionus) disturbed by all-terrain vehicles (Yarmoloy et al., 1988), caribou (Rangifer tarandus caribou) disturbed by seismic exploration blasts (Bradshaw et al., 1998), and caribou disturbed by lowelevation military jet fights (Luick et al., 1996, Harrington and Veitch, 1992). Similarly, a study of elk (Cervus elaphus) that were disturbed experimentally by pedestrians concluded that the ratio of young to mothers was inversely related to disturbance rate (Phillips and Alldredge, 2000). However, Ridgway et al. (2006) reported that increased vigilance in bottlenose dolphins exposed to sound over a five-day period in open-air, open-water enclosures in E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules San Diego Bay did not cause any sleep deprivation or stress effects such as changes in cortisol or epinephrine levels. The primary mechanism by which increased vigilance and disturbance appear to affect the fitness of individual animals is by disrupting an animal’s time budget and, as a result, reducing the time they might spend foraging and resting (which increases an animal’s activity rate and energy demand while decreasing their caloric intake/energy). An example of this concept with terrestrial species involved a study of grizzly bears (Ursus horribilis) that reported that bears disturbed by hikers reduced their energy intake by an average of 12 kilocalories/min (50.2 × 103 kiloJoules/min), and spent energy fleeing or acting aggressively toward hikers (White et al., 1999). Lusseau and Bejder (2007) present data from three long-term studies illustrating the connections between disturbance from whale-watching boats and population-level effects in cetaceans. In Shark Bay Australia, the abundance of bottlenose dolphins was compared within adjacent control and tourism sites over three consecutive 4.5year periods of increasing tourism levels. Between the second and third time periods, in which tourism doubled, dolphin abundance decreased by 15 percent in the tourism area and did not change significantly in the control area. In Fiordland, New Zealand, two populations (Milford and Doubtful Sounds) of bottlenose dolphins with tourism levels that differed by a factor of seven were observed and significant increases in travelling time and decreases in resting time were documented for both. Consistent shortterm avoidance strategies were observed in response to tour boats until a threshold of disturbance was reached (average 68 minutes between interactions), after which the response switched to a longer-term habitat displacement strategy. For one population, tourism only occurred in a part of the home range. However, tourism occurred throughout the home range of the Doubtful Sound population and once boat traffic increased beyond the 68-minute threshold (resulting in abandonment of their home range/ preferred habitat), reproductive success drastically decreased (increased stillbirths) and abundance decreased significantly (from 67 to 56 individuals in a short period). Last, in a study of northern resident killer whales off Vancouver Island, exposure to boat traffic was shown to reduce foraging opportunities and increase traveling time. A simple bioenergetics model was VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 applied to show that the reduced foraging opportunities equated to a decreased energy intake of 18 percent, while the increased traveling incurred an increased energy output of 3–4 percent, which suggests that a management action based on avoiding interference with foraging might be particularly effective. On a related note, many animals perform vital functions, such as feeding, resting, traveling, and socializing, on a diel cycle (24-hr cycle). Behavioral reactions to noise exposure (such as disruption of critical life functions, displacement, or avoidance of important habitat) are more likely to be significant for fitness if they last more than one diel cycle or recur on subsequent days (Southall et al., 2007). Consequently, a behavioral response lasting less than one day and not recurring on subsequent days is not considered particularly severe unless it could directly affect reproduction or survival (Southall et al., 2007). It is important to note the difference between behavioral reactions lasting or recurring over multiple days and anthropogenic activities lasting or recurring over multiple days. For example, just because at-sea exercises last for multiple days does not necessarily mean that individual animals will be either exposed to those activity-related stressors (i.e., sonar) for multiple days or further, exposed in a manner that would result in sustained multi-day substantive behavioral responses. Stone (2015a) reported data from atsea observations during 1,196 airgun surveys from 1994 to 2010. When large arrays of airguns (considered to be 500 in3 or more) were firing, lateral displacement, more localized avoidance, or other changes in behavior were evident for most odontocetes. However, significant responses to large arrays were found only for the minke whale and fin whale. Behavioral responses observed included changes in swimming or surfacing behavior, with indications that cetaceans remained near the water surface at these times. Cetaceans were recorded as feeding less often when large arrays were active. Monitoring of gray whales during an air gun survey included recording whale movements and respirations pre-, during-, and post-seismic survey (Gailey et al., 2016). Behavioral state and water depth were the best ‘natural’ predictors of whale movements and respiration and, after considering natural variation, none of the response variables were significantly associated with survey or vessel sounds. In order to understand how the effects of activities may or may not impact PO 00000 Frm 00041 Fmt 4701 Sfmt 4702 33953 species and stocks of marine mammals, it is necessary to understand not only what the likely disturbances are going to be, but how those disturbances may affect the reproductive success and survivorship of individuals, and then how those impacts to individuals translate to population-level effects. Following on the earlier work of a committee of the U.S. National Research Council (NRC, 2005), New et al. (2014), in an effort termed the Potential Consequences of Disturbance (PCoD), outline an updated conceptual model of the relationships linking disturbance to changes in behavior and physiology, health, vital rates, and population dynamics. In this framework, behavioral and physiological changes can have direct (acute) effects on vital rates, such as when changes in habitat use or increased stress levels raise the probability of mother-calf separation or predation; they can have indirect and long-term (chronic) effects on vital rates, such as when changes in time/energy budgets or increased disease susceptibility affect health, which then affects vital rates; or they can have no effect to vital rates (New et al., 2014). In addition to outlining this general framework and compiling the relevant literature that supports it, the authors chose four example species for which extensive long-term monitoring data exist (southern elephant seals, North Atlantic right whales, Ziphidae beaked whales, and bottlenose dolphins) and developed state-space energetic models that can be used to forecast longer-term, population-level impacts from behavioral changes. While these are very specific models with very specific data requirements that cannot yet be applied broadly to project-specific risk assessments for the majority of species, as well as requiring significant resources and time to conduct (more than is typically available to support regulatory compliance for one project), they are a critical first step towards being able to quantify the likelihood of a population level effect. Since New et al. (2014), several publications have described models developed to examine the long-term effects of environmental or anthropogenic disturbance of foraging on various life stages of selected species (sperm whale, Farmer et al. (2018); California sea lion, McHuron et al. (2018); and blue whale, Pirotta, et al. (2018a)). These models continue to add to refinement to the approaches to the population consequences of disturbance (PCOD) framework. Such models also help identify what data inputs require further investigation. Pirotta et al. E:\FR\FM\02JNP2.SGM 02JNP2 33954 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 2005a; 2005b, Romero, 2004; Sih et al., 2004). Historically, stranding reporting and response efforts have been inconsistent, although significant improvements have occurred over the last 25 years. Stranding and Mortality Reporting forms for basic (‘‘Level A’’) information, rehabilitation disposition, The definition for a stranding under title IV of the MMPA is that (A) a marine and human interaction have been standardized nationally (available at mammal is dead and is (i) on a beach https://www.fisheries.noaa.gov/ or shore of the United States; or (ii) in national/marine-mammal-protection/ waters under the jurisdiction of the level-data-collection-marine-mammalUnited States (including any navigable waters); or (B) a marine mammal is alive stranding-events). However, data collected beyond basic information and is (i) on a beach or shore of the varies by region (and may vary from United States and is unable to return to the water; (ii) on a beach or shore of the case to case), and are not standardized across the United States. Logistical United States and, although able to conditions such as weather, time, return to the water, is in need of location, and decomposition state may apparent medical attention; or (iii) in also affect the ability of the stranding the waters under the jurisdiction of the network to thoroughly examine a United States (including any navigable specimen (Carretta et al., 2016b; Moore waters), but is unable to return to its et al., 2013). While the investigation of natural habitat under its own power or stranded animals provides insight into without assistance (see MMPA section the types of threats marine mammal 410(3)). This definition is useful for considering stranding events even when populations face, full investigations are only possible and conducted on a small they occur beyond lands and waters fraction of the total number of under the jurisdiction of the United strandings that occur, limiting our States. understanding of the causes of Marine mammal strandings have been strandings (Carretta et al., 2016a). linked to a variety of causes, such as Additionally, and due to the variability illness from exposure to infectious in effort and data collected, the ability agents, biotoxins, or parasites; to interpret long-term trends in stranded starvation; unusual oceanographic or marine mammals is complicated. weather events; or anthropogenic causes In the United States from 2006–2017, including fishery interaction, ship there were 19,430 cetacean strandings strike, entrainment, entrapment, sound and 55,833 pinniped strandings (75,263 exposure, or combinations of these total) (P. Onens, NMFS, pers comm., stressors sustained concurrently or in 2019). Several mass strandings series. Historically, the cause or causes (strandings that involve two or more of most strandings have remained individuals of the same species, unknown (Geraci et al., 1976; Eaton, excluding a single mother-calf pair) that 1979, Odell et al., 1980; Best, 1982), but have occurred over the past two decades the development of trained, professional have been associated with stranding response networks and anthropogenic activities that introduced improved analyses have led to a greater sound into the marine environment understanding of marine mammal such as naval operations and seismic stranding causes (Simeone and Moore surveys. An in-depth discussion of 2017). strandings is in the Navy’s Technical Numerous studies suggest that the Report on Marine Mammal Strandings physiology, behavior, habitat, social Associated with U.S. Navy Sonar relationships, age, or condition of Activities (U.S. Navy Marine Mammal cetaceans may cause them to strand or Program & Space and Naval Warfare might predispose them to strand when Systems Command Center Pacific, exposed to another phenomenon. These 2017). suggestions are consistent with the Worldwide, there have been several conclusions of numerous other studies efforts to identify relationships between cetacean mass stranding events and that have demonstrated that military active sonar (Cox et al., 2006, combinations of dissimilar stressors Hildebrand, 2004; IWC, 2005; Taylor et commonly combine to kill an animal or al., 2004). For example, based on a dramatically reduce its fitness, even review of mass stranding events around though one exposure without the other the world consisting of two or more does not produce the same result individuals of Cuvier’s beaked whales, (Bernaldo de Quiros et al., 2019; Chroussos, 2000; Creel, 2005; DeVries et records from the International Whaling Commission (IWC) (2005) show that a al., 2003; Fair and Becker, 2000; Foley quarter (9 of 41) were associated with et al., 2001; Moberg, 2000; Relyea, khammond on DSKJM1Z7X2PROD with PROPOSALS2 (2018b) provides a review of the PCOD framework with details on each step of the process and approaches to applying real data or simulations to achieve each step. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00042 Fmt 4701 Sfmt 4702 concurrent naval patrol, explosion, maneuvers, or MFAS. D’Amico et al. (2009) reviewed beaked whale stranding data compiled primarily from the published literature, which provides an incomplete record of stranding events, as many are not written up for publication, along with unpublished information from some regions of the world. Most of the stranding events reviewed by the IWC involved beaked whales. A mass stranding of Cuvier’s beaked whales in the eastern Mediterranean Sea occurred in 1996 (Frantzis, 1998), and mass stranding events involving Gervais’ beaked whales, Blainville’s beaked whales, and Cuvier’s beaked whales occurred off the coast of the Canary Islands in the late 1980s (Simmonds and Lopez-Jurado, 1991). The stranding events that occurred in the Canary Islands and Kyparissiakos Gulf in the late 1990s and the Bahamas in 2000 have been the most intensivelystudied mass stranding events and have been associated with naval maneuvers involving the use of tactical sonar. Other cetacean species with naval sonar implicated in stranding events include harbor porpoise (Phocoena phocoena) (Norman et al., 2004, Wright et al., 2013) and common dolphin (Delphinus delphis) (Jepson and Deaville 2009). Strandings Associated With Impulsive Sound Silver Strand During a Navy training event on March 4, 2011 at the Silver Strand Training Complex in San Diego, California, three or possibly four dolphins were killed in an explosion. During an underwater detonation training event, a pod of 100 to 150 longbeaked common dolphins were observed moving towards the 700-yd (640.1 m) exclusion zone around the explosive charge, monitored by personnel in a safety boat and participants in a dive boat. Approximately five minutes remained on a time-delay fuse connected to a single 8.76 lb (3.97 kg) explosive charge (C–4 and detonation cord). Although the dive boat was placed between the pod and the explosive in an effort to guide the dolphins away from the area, that effort was unsuccessful and three longbeaked common dolphins near the explosion died. In addition to the three dolphins found dead on March 4, the remains of a fourth dolphin were discovered on March 7, 2011 near Oceanside, California (3 days later and approximately 68 km north of the detonation), which might also have been related to this event. Association of the E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules fourth stranding with the training event is uncertain because dolphins strand on a regular basis in the San Diego area. Details such as the dolphins’ depth and distance from the explosive at the time of the detonation could not be estimated from the 250 yd (228.6 m) standoff point of the observers in the dive boat or the safety boat. These dolphin mortalities are the only known occurrence of a U.S. Navy training or testing event involving impulsive energy (underwater detonation) that caused mortality or injury to a marine mammal. Despite this being a rare occurrence, the Navy reviewed training requirements, safety procedures, and possible mitigation measures and implemented changes to reduce the potential for this to occur in the future. Discussions of procedures associated with underwater explosives training and other training events are presented in the Proposed Mitigation Measures section. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Kyle of Durness, Scotland On July 22, 2011 a mass stranding event involving long-finned pilot whales occurred at Kyle of Durness, Scotland. An investigation by Brownlow et al. (2015) considered unexploded ordnance detonation activities at a Ministry of Defense bombing range, conducted by the Royal Navy prior to and during the strandings, as a plausible contributing factor in the mass stranding event. While Brownlow et al. (2015) concluded that the serial detonations of underwater ordnance were an influential factor in the mass stranding event (along with the presence of a potentially compromised animal and navigational error in a topographically complex region), they also suggest that mitigation measures—which included observations from a zodiac only and by personnel not experienced in marine mammal observation, among other deficiencies—were likely insufficient to assess if cetaceans were in the vicinity of the detonations. The authors also cite information from the Ministry of Defense indicating ‘‘an extraordinarily high level of activity’’ (i.e., frequency and intensity of underwater explosions) on the range in the days leading up to the stranding. Gulf of California, Mexico One stranding event was contemporaneous with and reasonably associated spatially with the use of seismic air guns. This event occurred in the Gulf of California, coincident with seismic reflection profiling by the R/V Maurice Ewing operated by Columbia University’s Lamont-Doherty Earth Observatory and involved two Cuvier’s VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 beaked whales (Hildebrand, 2004). The vessel had been firing an array of 20 air guns with a total volume of 8,500 in3 (Hildebrand, 2004; Taylor et al., 2004). Strandings Associated With Active Sonar Over the past 21 years, there have been five stranding events coincident with U.S. Navy MF active sonar use in which exposure to sonar is believed to have been a contributing factor: Greece (1996); the Bahamas (2000); Madeira (2000); Canary Islands (2002); and Spain (2006) (Cox et al., 2006; Fernandez, 2006; U.S. Navy Marine Mammal Program & Space and Naval Warfare Systems Command Center Pacific, 2017). These five mass strandings have resulted in about 40 known cetacean deaths consisting mostly of beaked whales and with close linkages to midfrequency active sonar activity. In these circumstances, exposure to nonimpulsive acoustic energy was considered a potential indirect cause of death of the marine mammals (Cox et al., 2006). Only one of these stranding events, the Bahamas (2000), was associated with exercises conducted by the U.S. Navy. Additionally, in 2004, during the Rim of the Pacific (RIMPAC) exercises, between 150 and 200 usually pelagic melon-headed whales occupied the shallow waters of Hanalei Bay, Kauai, Hawaii for over 28 hours. NMFS determined that MFAS was a plausible, if not likely, contributing factor in what may have been a confluence of events that led to the Hanalei Bay stranding. A number of other stranding events coincident with the operation of MFAS, including the death of beaked whales or other species (minke whales, dwarf sperm whales, pilot whales), have been reported; however, the majority have not been investigated to the degree necessary to determine the cause of the stranding. Most recently, the Independent Scientific Review Panel investigating potential contributing factors to a 2008 mass stranding of melon-headed whales in Antsohihy, Madagascar released its final report suggesting that the stranding was likely initially triggered by an industry seismic survey (Southall et al., 2013). This report suggests that the operation of a commercial high-powered 12 kHz multibeam echosounder during an industry seismic survey was a plausible and likely initial trigger that caused a large group of melon-headed whales to leave their typical habitat and then ultimately strand as a result of secondary factors such as malnourishment and dehydration. The report indicates that the risk of this particular convergence of factors and ultimate outcome is likely PO 00000 Frm 00043 Fmt 4701 Sfmt 4702 33955 very low, but recommends that the potential be considered in environmental planning. Because of the association between tactical midfrequency active sonar use and a small number of marine mammal strandings, the Navy and NMFS have been considering and addressing the potential for strandings in association with Navy activities for years. In addition to the proposed mitigation measures intended to more broadly minimize impacts to marine mammals, the Navy will abide by the Notification and Reporting Plan, which sets out notification, reporting, and other requirements when dead, injured, or stranded marine mammals are detected in certain circumstances. Greece (1996) Twelve Cuvier’s beaked whales stranded atypically (in both time and space) along a 38.2-km strand of the Kyparissiakos Gulf coast on May 12 and 13, 1996 (Frantzis, 1998). From May 11 through May 15, the North Atlantic Treaty Organization (NATO) research vessel Alliance was conducting sonar tests with signals of 600 Hz and 3 kHz and source levels of 228 and 226 dB re: 1mPa, respectively (D’Amico and Verboom, 1998; D’Spain et al., 2006). The timing and location of the testing encompassed the time and location of the strandings (Frantzis, 1998). Necropsies of eight of the animals were performed but were limited to basic external examination and sampling of stomach contents, blood, and skin. No ears or organs were collected, and no histological samples were preserved. No significant apparent abnormalities or wounds were found, however examination of photos of the animals, taken soon after their death, revealed that the eyes of at least four of the individuals were bleeding (Frantzis, 2004). Stomach contents contained the flesh of cephalopods, indicating that feeding had recently taken place (Frantzis, 1998). All available information regarding the conditions associated with this stranding event was compiled, and many potential causes were examined including major pollution events, prominent tectonic activity, unusual physical or meteorological events, magnetic anomalies, epizootics, and conventional military activities (International Council for the Exploration of the Sea, 2005a). However, none of these potential causes coincided in time or space with the mass stranding, or could explain its characteristics (International Council for the Exploration of the Sea, 2005a). The robust condition of the animals, plus the E:\FR\FM\02JNP2.SGM 02JNP2 33956 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 recent stomach contents, is inconsistent with pathogenic causes. In addition, environmental causes can be ruled out as there were no unusual environmental circumstances or events before or during this time period and within the general proximity (Frantzis, 2004). Because of the rarity of this mass stranding of Cuvier’s beaked whales in the Kyparissiakos Gulf (first one in historical records), the probability for the two events (the military exercises and the strandings) to coincide in time and location, while being independent of each other, was thought to be extremely low (Frantzis, 1998). However, because full necropsies had not been conducted, and no abnormalities were noted, the cause of the strandings could not be precisely determined (Cox et al., 2006). A Bioacoustics Panel convened by NATO concluded that the evidence available did not allow them to accept or reject sonar exposures as a causal agent in these stranding events. The analysis of this stranding event provided support for, but no clear evidence for, the causeand-effect relationship of tactical sonar training activities and beaked whale strandings (Cox et al., 2006). Bahamas (2000) NMFS and the Navy prepared a joint report addressing the multi-species stranding in the Bahamas in 2000, which took place within 24 hrs of U.S. Navy ships using MFAS as they passed through the Northeast and Northwest Providence Channels on March 15–16, 2000. The ships, which operated both AN/SQS–53C and AN/SQS–56, moved through the channel while emitting sonar pings approximately every 24 seconds. Of the 17 cetaceans that stranded over a 36-hour period (Cuvier’s beaked whales, Blainville’s beaked whales, minke whales, and a spotted dolphin), seven animals died on the beach (five Cuvier’s beaked whales, one Blainville’s beaked whale, and the spotted dolphin), while the other 10 were returned to the water alive (though their ultimate fate is unknown). As discussed in the Bahamas report (DOC/ DON, 2001), there is no likely association between the minke whale and spotted dolphin strandings and the operation of MFAS. Necropsies were performed on five of the stranded beaked whales. All five necropsied beaked whales were in good body condition, showing no signs of infection, disease, ship strike, blunt trauma, or fishery related injuries, and three still had food remains in their stomachs. Auditory structural damage was discovered in four of the whales, specifically bloody effusions or VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 hemorrhaging around the ears. Bilateral intracochlear and unilateral temporal region subarachnoid hemorrhage, with blood clots in the lateral ventricles, were found in two of the whales. Three of the whales had small hemorrhages in their acoustic fats (located along the jaw and in the melon). A comprehensive investigation was conducted and all possible causes of the stranding event were considered, whether they seemed likely at the outset or not. Based on the way in which the strandings coincided with ongoing naval activity involving tactical MFAS use, in terms of both time and geography, the nature of the physiological effects experienced by the dead animals, and the absence of any other acoustic sources, the investigation team concluded that MFAS aboard U.S. Navy ships that were in use during the active sonar exercise in question were the most plausible source of this acoustic or impulse trauma to beaked whales. This sound source was active in a complex environment that included the presence of a surface duct, unusual and steep bathymetry, a constricted channel with limited egress, intensive use of multiple, active sonar units over an extended period of time, and the presence of beaked whales that appear to be sensitive to the frequencies produced by these active sonars. The investigation team concluded that the cause of this stranding event was the confluence of the Navy MFAS and these contributory factors working together, and further recommended that the Navy avoid operating MFAS in situations where these five factors would be likely to occur. This report does not conclude that all five of these factors must be present for a stranding to occur, nor that beaked whales are the only species that could potentially be affected by the confluence of the other factors. Based on this, NMFS believes that the operation of MFAS in situations where surface ducts exist, or in marine environments defined by steep bathymetry and/or constricted channels may increase the likelihood of producing a sound field with the potential to cause cetaceans (especially beaked whales) to strand, and therefore, suggests the need for increased vigilance while operating MFAS in these areas, especially when beaked whales (or potentially other deep divers) are likely present. Madeira, Portugal (2000) From May 10–14, 2000, three Cuvier’s beaked whales were found atypically stranded on two islands in the Madeira archipelago, Portugal (Cox et al., 2006). A fourth animal was reported floating in the Madeiran waters by fisherman but PO 00000 Frm 00044 Fmt 4701 Sfmt 4702 did not come ashore (Woods Hole Oceanographic Institution, 2005). Joint NATO amphibious training peacekeeping exercises involving participants from 17 countries and 80 warships, took place in Portugal during May 2–15, 2000. The bodies of the three stranded whales were examined post mortem (Woods Hole Oceanographic Institution, 2005), though only one of the stranded whales was fresh enough (24 hours after stranding) to be necropsied (Cox et al., 2006). Results from the necropsy revealed evidence of hemorrhage and congestion in the right lung and both kidneys (Cox et al., 2006). There was also evidence of intercochlear and intracranial hemorrhage similar to that which was observed in the whales that stranded in the Bahamas event (Cox et al., 2006). There were no signs of blunt trauma, and no major fractures (Woods Hole Oceanographic Institution, 2005). The cranial sinuses and airways were found to be clear with little or no fluid deposition, which may indicate good preservation of tissues (Woods Hole Oceanographic Institution, 2005). Several observations on the Madeira stranded beaked whales, such as the pattern of injury to the auditory system, are the same as those observed in the Bahamas strandings. Blood in and around the eyes, kidney lesions, pleural hemorrhages, and congestion in the lungs are particularly consistent with the pathologies from the whales stranded in the Bahamas, and are consistent with stress and pressure related trauma. The similarities in pathology and stranding patterns between these two events suggest that a similar pressure event may have precipitated or contributed to the strandings at both sites (Woods Hole Oceanographic Institution, 2005). Even though no definitive causal link can be made between the stranding event and naval exercises, certain conditions may have existed in the exercise area that, in their aggregate, may have contributed to the marine mammal strandings (Freitas, 2004): Exercises were conducted in areas of at least 547 fathoms (1,000 m) depth near a shoreline where there is a rapid change in bathymetry on the order of 547 to 3,281 fathoms (1,000 to 6,000 m) occurring across a relatively short horizontal distance (Freitas, 2004); multiple ships were operating around Madeira, though it is not known if MFAS was used, and the specifics of the sound sources used are unknown (Cox et al., 2006, Freitas, 2004); and exercises took place in an area surrounded by landmasses separated by less than 35 nmi (65 km) and at least 10 nmi (19 km) E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 in length, or in an embayment. Exercises involving multiple ships employing MFAS near land may produce sound directed towards a channel or embayment that may cut off the lines of egress for marine mammals (Freitas, 2004). Canary Islands, Spain (2002) The southeastern area within the Canary Islands is well known for aggregations of beaked whales due to its ocean depths of greater than 547 fathoms (1,000 m) within a few hundred meters of the coastline (Fernandez et al., 2005). On September 24, 2002, 14 beaked whales were found stranded on Fuerteventura and Lanzarote Islands in the Canary Islands (International Council for Exploration of the Sea, 2005a). Seven whales died, while the remaining seven live whales were returned to deeper waters (Fernandez et al., 2005). Four beaked whales were found stranded dead over the next three days either on the coast or floating offshore. These strandings occurred within close proximity of an international naval exercise that utilized MFAS and involved numerous surface warships and several submarines. Strandings began about four hours after the onset of MFAS activity (International Council for Exploration of the Sea, 2005a; Fernandez et al., 2005). Eight Cuvier’s beaked whales, one Blainville’s beaked whale, and one Gervais’ beaked whale were necropsied, 6 of them within 12 hours of stranding (Fernandez et al., 2005). No pathogenic bacteria were isolated from the carcasses (Jepson et al., 2003). The animals displayed severe vascular congestion and hemorrhage especially around the tissues in the jaw, ears, brain, and kidneys, displaying marked disseminated microvascular hemorrhages associated with widespread fat emboli (Jepson et al., 2003; International Council for Exploration of the Sea, 2005a). Several organs contained intravascular bubbles, although definitive evidence of gas embolism in vivo is difficult to determine after death (Jepson et al., 2003). The livers of the necropsied animals were the most consistently affected organ, which contained macroscopic gas-filled cavities and had variable degrees of fibrotic encapsulation. In some animals, cavitary lesions had extensively replaced the normal tissue (Jepson et al., 2003). Stomachs contained a large amount of fresh and undigested contents, suggesting a rapid onset of disease and death (Fernandez et al., 2005). Head and neck lymph nodes were enlarged and congested, and VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 parasites were found in the kidneys of all animals (Fernandez et al., 2005). The association of NATO MFAS use close in space and time to the beaked whale strandings, and the similarity between this stranding event and previous beaked whale mass strandings coincident with sonar use, suggests that a similar scenario and causative mechanism of stranding may be shared between the events. Beaked whales stranded in this event demonstrated brain and auditory system injuries, hemorrhages, and congestion in multiple organs, similar to the pathological findings of the Bahamas and Madeira stranding events. In addition, the necropsy results of the Canary Islands stranding event lead to the hypothesis that the presence of disseminated and widespread gas bubbles and fat emboli were indicative of nitrogen bubble formation, similar to what might be expected in decompression sickness (Jepson et al., 2003; Ferna´ndez et al., 2005). Hanalei Bay (2004) On July 3 and 4, 2004, approximately 150 to 200 melon-headed whales occupied the shallow waters of Hanalei Bay, Kauai, Hawaii for over 28 hrs. Attendees of a canoe blessing observed the animals entering the Bay in a single wave formation at 7 a.m. on July 3, 2004. The animals were observed moving back into the shore from the mouth of the Bay at 9 a.m. The usually pelagic animals milled in the shallow bay and were returned to deeper water with human assistance beginning at 9:30 a.m. on July 4, 2004, and were out of sight by 10:30 a.m. Only one animal, a calf, was known to have died following this event. The animal was noted alive and alone in the Bay on the afternoon of July 4, 2004, and was found dead in the Bay the morning of July 5, 2004. A full necropsy, magnetic resonance imaging, and computerized tomography examination were performed on the calf to determine the manner and cause of death. The combination of imaging, necropsy and histological analyses found no evidence of infectious, internal traumatic, congenital, or toxic factors. Cause of death could not be definitively determined, but it is likely that maternal separation, poor nutritional condition, and dehydration contributed to the final demise of the animal. Although it is not known when the calf was separated from its mother, the animals’ movement into the Bay and subsequent milling and re-grouping may have contributed to the separation or lack of nursing, especially if the PO 00000 Frm 00045 Fmt 4701 Sfmt 4702 33957 maternal bond was weak or this was an inexperienced mother with her first calf. Environmental factors, abiotic and biotic, were analyzed for any anomalous occurrences that would have contributed to the animals entering and remaining in Hanalei Bay. The Bay’s bathymetry is similar to many other sites within the Hawaiian Island chain and dissimilar to sites that have been associated with mass strandings in other parts of the United States. The weather conditions appeared to be normal for that time of year with no fronts or other significant features noted. There was no evidence of unusual distribution, occurrence of predator or prey species, or unusual harmful algal blooms, although Mobley et al. (2007) suggested that the full moon cycle that occurred at that time may have influenced a run of squid into the Bay. Weather patterns and bathymetry that have been associated with mass strandings elsewhere were not found to occur in this instance. The Hanalei event was spatially and temporally correlated with RIMPAC. Official sonar training and tracking exercises in the Pacific Missile Range Facility (PMRF) warning area did not commence until approximately 8 a.m. on July 3 and were thus ruled out as a possible trigger for the initial movement into the bay. However, six naval surface vessels transiting to the operational area on July 2 intermittently transmitted active sonar (for approximately nine hours total from 1:15 p.m. to 12:30 a.m.) as they approached from the south. The potential for these transmissions to have triggered the whales’ movement into Hanalei Bay was investigated. Analyses with the information available indicated that animals to the south and east of Kaua’i could have detected active sonar transmissions on July 2, and reached Hanalei Bay on or before 7 a.m. on July 3. However, data limitations regarding the position of the whales prior to their arrival in the Bay, the magnitude of sonar exposure, behavioral responses of melon-headed whales to acoustic stimuli, and other possible relevant factors preclude a conclusive finding regarding the role of sonar in triggering this event. Propagation modeling suggests that transmissions from sonar use during the July 3 exercise in the PMRF warning area may have been detectable at the mouth of the bay. If the animals responded negatively to these signals, it may have contributed to their continued presence in the bay. The U.S. Navy ceased all active sonar transmissions during exercises in this range on the afternoon of July 3. Subsequent to the cessation of sonar E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33958 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules use, the animals were herded out of the bay. While causation of this stranding event may never be unequivocally determined, NMFS considers the active sonar transmissions of July 2–3, 2004, a plausible, if not likely, contributing factor in what may have been a confluence of events. This conclusion is based on the following: (1) The evidently anomalous nature of the stranding; (2) its close spatiotemporal correlation with wide-scale, sustained use of sonar systems previously associated with stranding of deep-diving marine mammals; (3) the directed movement of two groups of transmitting vessels toward the southeast and southwest coast of Kauai; (4) the results of acoustic propagation modeling and an analysis of possible animal transit times to the bay; and (5) the absence of any other compelling causative explanation. The initiation and persistence of this event may have resulted from an interaction of biological and physical factors. The biological factors may have included the presence of an apparently uncommon, deep-diving cetacean species (and possibly an offshore, non-resident group), social interactions among the animals before or after they entered the bay, and/or unknown predator or prey conditions. The physical factors may have included the presence of nearby deep water, multiple vessels transiting in a directed manner while transmitting active sonar over a sustained period, the presence of surface sound ducting conditions, and/or intermittent and random human interactions while the animals were in the bay. A separate event involving melonheaded whales and rough-toothed dolphins took place over the same period of time in the Northern Mariana Islands (Jefferson et al., 2006), which is several thousand miles from Hawaii. Some 500 to 700 melon-headed whales came into Sasanhaya Bay on July 4, 2004, near the island of Rota and then left of their own accord after 5.5 hours; no known active sonar transmissions occurred in the vicinity of that event. The Rota incident led to scientific debate regarding what, if any, relationship the event had to the simultaneous events in Hawaii and whether they might be related by some common factor (e.g., there was a full moon on July 2, 2004, as well as during other melon-headed whale strandings and nearshore aggregations (Brownell et al., 2009; Lignon et al., 2007; Mobley et al., 2007). Brownell et al. (2009) compared the two incidents, along with one other stranding incident at Nuka Hiva in French Polynesia and normal VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 resting behaviors observed at Palmyra Island, in regard to physical features in the areas, melon-headed whale behavior, and lunar cycles. Brownell et al., (2009) concluded that the rapid entry of the whales into Hanalei Bay, their movement into very shallow water far from the 100-m contour, their milling behavior (typical pre-stranding behavior), and their reluctance to leave the bay constituted an unusual event that was not similar to the events that occurred at Rota, which appear to be similar to observations of melon-headed whales resting normally at Palmyra Island. Additionally, there was no correlation between lunar cycle and the types of behaviors observed in the Brownell et al. (2009) examples. Spain (2006) The Spanish Cetacean Society reported an atypical mass stranding of four beaked whales that occurred January 26, 2006, on the southeast coast of Spain, near Moja´car (Gulf of Vera) in the Western Mediterranean Sea. According to the report, two of the whales were discovered the evening of January 26 and were found to be still alive. Two other whales were discovered during the day on January 27, but had already died. The first three animals were located near the town of Moja´car and the fourth animal was found dead, a few kilometers north of the first three animals. From January 25–26, 2006, Standing NATO Response Force Maritime Group Two (five of seven ships including one U.S. ship under NATO Operational Control) had conducted active sonar training against a Spanish submarine within 50 nmi (93 km) of the stranding site. Veterinary pathologists necropsied the two male and two female Cuvier’s beaked whales. According to the pathologists, the most likely primary cause of this type of beaked whale mass stranding event was anthropogenic acoustic activities, most probably antisubmarine MFAS used during the military naval exercises. However, no positive acoustic link was established as a direct cause of the stranding. Even though no causal link can be made between the stranding event and naval exercises, certain conditions may have existed in the exercise area that, in their aggregate, may have contributed to the marine mammal strandings (Freitas, 2004). Exercises were conducted in areas of at least 547 fathoms (1,000 m) depth near a shoreline where there is a rapid change in bathymetry on the order of 547 to 3,281 fathoms (1,000 to 6,000 m) occurring across a relatively short horizontal distance (Freitas, 2004). Multiple ships (in this instance, five) PO 00000 Frm 00046 Fmt 4701 Sfmt 4702 were operating MFAS in the same area over extended periods of time (in this case, 20 hours) in close proximity; and exercises took place in an area surrounded by landmasses, or in an embayment. Exercises involving multiple ships employing MFAS near land may have produced sound directed towards a channel or embayment that may have cut off the lines of egress for the affected marine mammals (Freitas, 2004). Behaviorally Mediated Responses to MFAS That May Lead to Stranding Although the confluence of Navy MFAS with the other contributory factors noted in the 2001 NMFS/Navy joint report was identified as the cause of the 2000 Bahamas stranding event, the specific mechanisms that led to that stranding (or the others) are not well understood, and there is uncertainty regarding the ordering of effects that led to the stranding. It is unclear whether beaked whales were directly injured by sound (e.g., acoustically mediated bubble growth, as addressed above) prior to stranding or whether a behavioral response to sound occurred that ultimately caused the beaked whales to be injured and strand. Although causal relationships between beaked whale stranding events and active sonar remain unknown, several authors have hypothesized that stranding events involving these species in the Bahamas and Canary Islands may have been triggered when the whales changed their dive behavior in a startled response to exposure to active sonar or to further avoid exposure (Cox et al., 2006; Rommel et al., 2006). These authors proposed three mechanisms by which the behavioral responses of beaked whales upon being exposed to active sonar might result in a stranding event. These include the following: Gas bubble formation caused by excessively fast surfacing; remaining at the surface too long when tissues are supersaturated with nitrogen; or diving prematurely when extended time at the surface is necessary to eliminate excess nitrogen. More specifically, beaked whales that occur in deep waters that are in close proximity to shallow waters (for example, the ‘‘canyon areas’’ that are cited in the Bahamas stranding event; see D’Spain and D’Amico, 2006), may respond to active sonar by swimming into shallow waters to avoid further exposures and strand if they were not able to swim back to deeper waters. Second, beaked whales exposed to active sonar might alter their dive behavior. Changes in their dive behavior might cause them to remain at the surface or at depth for extended periods E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules of time which could lead to hypoxia directly by increasing their oxygen demands or indirectly by increasing their energy expenditures (to remain at depth) and increase their oxygen demands as a result. If beaked whales are at depth when they detect a ping from an active sonar transmission and change their dive profile, this could lead to the formation of significant gas bubbles, which could damage multiple organs or interfere with normal physiological function (Cox et al., 2006; Rommel et al., 2006; Zimmer and Tyack, 2007). Baird et al. (2005) found that slow ascent rates from deep dives and long periods of time spent within 50 m of the surface were typical for both Cuvier’s and Blainville’s beaked whales, the two species involved in mass strandings related to naval sonar. These two behavioral mechanisms may be necessary to purge excessive dissolved nitrogen concentrated in their tissues during their frequent long dives (Baird et al., 2005). Baird et al. (2005) further suggests that abnormally rapid ascents or premature dives in response to highintensity sonar could indirectly result in physical harm to the beaked whales, through the mechanisms described above (gas bubble formation or nonelimination of excess nitrogen). In a review of the previously published data on the potential impacts of sonar on beaked whales, Bernaldo de Quiro´s et al. (2019) suggested that the effect of mid-frequency active sonar on beaked whales varies among individuals or populations, and that predisposing conditions such as previous exposure to sonar and individual health risk factors may contribute to individual outcomes (such as decompression sickness). Because many species of marine mammals make repetitive and prolonged dives to great depths, it has long been assumed that marine mammals have evolved physiological mechanisms to protect against the effects of rapid and repeated decompressions. Although several investigators have identified physiological adaptations that may protect marine mammals against nitrogen gas supersaturation (alveolar collapse and elective circulation; Kooyman et al., 1972; Ridgway and Howard, 1979), Ridgway and Howard (1979) reported that bottlenose dolphins that were trained to dive repeatedly had muscle tissues that were substantially supersaturated with nitrogen gas. Houser et al. (2001) used these data to model the accumulation of nitrogen gas within the muscle tissue of other marine mammal species and concluded that cetaceans that dive deep and have slow VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 ascent or descent speeds would have tissues that are more supersaturated with nitrogen gas than other marine mammals. Based on these data, Cox et al. (2006) hypothesized that a critical dive sequence might make beaked whales more prone to stranding in response to acoustic exposures. The sequence began with (1) very deep (to depths as deep as 2 km) and long (as long as 90 minutes) foraging dives; (2) relatively slow, controlled ascents; and (3) a series of ‘‘bounce’’ dives between 100 and 400 m in depth (see also Zimmer and Tyack, 2007). They concluded that acoustic exposures that disrupted any part of this dive sequence (for example, causing beaked whales to spend more time at surface without the bounce dives that are necessary to recover from the deep dive) could produce excessive levels of nitrogen supersaturation in their tissues, leading to gas bubble and emboli formation that produces pathologies similar to decompression sickness. Zimmer and Tyack (2007) modeled nitrogen tension and bubble growth in several tissue compartments for several hypothetical dive profiles and concluded that repetitive shallow dives (defined as a dive where depth does not exceed the depth of alveolar collapse, approximately 72 m for Cuvier’s beaked whale), perhaps as a consequence of an extended avoidance reaction to sonar sound, could pose a risk for decompression sickness and that this risk should increase with the duration of the response. Their models also suggested that unrealistically rapid rates of ascent from normal dive behaviors are unlikely to result in supersaturation to the extent that bubble formation would be expected. Tyack et al. (2006) suggested that emboli observed in animals exposed to mid-frequency range sonar (Jepson et al., 2003; Fernandez et al., 2005; Ferna´ndez et al., 2012) could stem from a behavioral response that involves repeated dives shallower than the depth of lung collapse. Given that nitrogen gas accumulation is a passive process (i.e., nitrogen is metabolically inert), a bottlenose dolphin was trained to repetitively dive a profile predicted to elevate nitrogen saturation to the point that nitrogen bubble formation was predicted to occur. However, inspection of the vascular system of the dolphin via ultrasound did not demonstrate the formation of asymptomatic nitrogen gas bubbles (Houser et al., 2007). Baird et al. (2008), in a beaked whale tagging study off Hawaii, showed that deep dives are equally common during day or night, but ‘‘bounce dives’’ are typically a daytime behavior, possibly associated PO 00000 Frm 00047 Fmt 4701 Sfmt 4702 33959 with visual predator avoidance. This may indicate that ‘‘bounce dives’’ are associated with something other than behavioral regulation of dissolved nitrogen levels, which would be necessary day and night. If marine mammals respond to a Navy vessel that is transmitting active sonar in the same way that they might respond to a predator, their probability of flight responses could increase when they perceive that Navy vessels are approaching them directly, because a direct approach may convey detection and intent to capture (Burger and Gochfeld, 1981, 1990; Cooper, 1997, 1998). The probability of flight responses could also increase as received levels of active sonar increase (and the ship is, therefore, closer) and as ship speeds increase (that is, as approach speeds increase). For example, the probability of flight responses in Dall’s sheep (Ovis dalli dalli) (Frid 2001a, b), ringed seals (Phoca hispida) (Born et al., 1999), Pacific brant (Branta bernic nigricans) and Canada geese (B. canadensis) increased as a helicopter or fixed-wing aircraft approached groups of these animals more directly (Ward et al., 1999). Bald eagles (Haliaeetus leucocephalus) perched on trees alongside a river were also more likely to flee from a paddle raft when their perches were closer to the river or were closer to the ground (Steidl and Anthony, 1996). Despite the many theories involving bubble formation (both as a direct cause of injury, see Acoustically-Induced Bubble Formation Due to Sonars and Other Pressure-related Injury section and an indirect cause of stranding), Southall et al. (2007) summarizes that there is either scientific disagreement or a lack of information regarding each of the following important points: (1) Received acoustical exposure conditions for animals involved in stranding events; (2) pathological interpretation of observed lesions in stranded marine mammals; (3) acoustic exposure conditions required to induce such physical trauma directly; (4) whether noise exposure may cause behavioral reactions (such as atypical diving behavior) that secondarily cause bubble formation and tissue damage; and (5) the extent the post mortem artifacts introduced by decomposition before sampling, handling, freezing, or necropsy procedures affect interpretation of observed lesions. Strandings in the NWTT Study Area Stranded marine mammals are reported along the entire western coast of the United States each year. Marine mammals strand due to natural or E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33960 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules anthropogenic causes; the majority of reported type of occurrences in marine mammal strandings in this region include fishery interactions, illness, predation, and vessel strikes (Carretta et al., 2017b; Helker et al., 2017; National Marine Fisheries Service, 2016). Stranding events that are associated with active UMEs on the Northwest Coast of the United States (inclusive of the NWTT Study Area) were previously discussed in the Description of Marine Mammals and Their Habitat in the Area of the Specified Activities section. From 2007–2016, 43,125 marine mammal strandings were confirmed by the West Coast Marine Mammal Stranding Network including 33,569 in California (including areas outside the NWTT Study Area), 3,776 in Oregon, and 5,780 in Washington (10 year Data Summary Report, West Coast Marine Mammal Stranding Network 2017). The most common marine mammal to strand in the NWTT Study Area was pinnipeds, which comprise 94 percent of strandings in California, 90 percent of strandings in Oregon, and 89 percent of strandings in Washington. The next most common group was odontocetes, with harbor porpoises being the most common species. Gray whales were reported to be the most common large whale species to strand on the U.S. West Coast in all states. Where evidence of human interaction can be determined (9 percent as reported in the 10-year summary), the most common source of interaction on the U.S. West Coast was fishery interaction for pinnipeds, small cetaceans and large whales. The Behm Canal portion of the Study Area is a very small portion of the Southeast Regional Subarea of the Alaska Marine Mammal Stranding Network. A 10-year summary report is not available in this region however, in 2019 there were 40 confirmed strandings in the entire Southeast Regional Subarea, and 30 of these strandings were harbor seals or Steller sea lions. One stranding event has been investigated for a possible link to Navy activities in the NWTT Study Area. Between May 2 and June 2, 2003, approximately 16 strandings involving 15 harbor porpoises and one Dall’s porpoise in the Eastern Strait of Juan de Fuca and Haro Strait were reported to the Northwest Marine Mammal Stranding Network. Given that the USS SHOUP was known to have operated sonar in the Haro strait on May 5, 2003, and that behavioral reactions of killer whales were possibly linked to these sonar operations, NMFS undertook an analysis of whether sonar caused the strandings of the porpoises (National Marine Fisheries Service, 2005). NMFS VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 determined that the 2003 strandings and similar harbor porpoise strandings over the following years were normal given a number of factors as described in Huggins et al. (2015). The 2015 NWTT FEIS/OEIS includes a comprehensive review of all strandings and the events involving the USS SHOUP on May 5, 2003. Additional information on this event is available in the Navy’s Technical Report on Marine Mammal Strandings Associated with U.S. Navy Sonar Activities (U.S. Department of the Navy, 2017b). In the years since the SHOUP incident, annual numbers of stranded porpoises have been comparable (and sometimes higher) and have also shown similar causes of death (when determinable) to the causes of death noted in the SHOUP investigation (Huggins et al., 2015). Marine Mammal Habitat The Navy’s proposed training and testing activities could potentially affect marine mammal habitat through the introduction of impacts to the prey species of marine mammals, acoustic habitat (sound in the water column), water quality, and biologically important habitat for marine mammals. Each of these potential effects was considered in the 2019 NWTT DSEIS/ OEIS and was determined by the Navy to have no effect on marine mammal habitat. Based on the information below and the supporting information included in the 2019 NWTT DSEIS/ OEIS, NMFS has determined that the proposed training and training activities would not have adverse or long-term impacts on marine mammal habitat. Effects to Prey Sound may affect marine mammals through impacts on the abundance, behavior, or distribution of prey species (e.g., crustaceans, cephalopods, fish, zooplankton). Marine mammal prey varies by species, season, and location and, for some species, is not well documented. Here, we describe studies regarding the effects of noise on known marine mammal prey. Fish utilize the soundscape and components of sound in their environment to perform important functions such as foraging, predator avoidance, mating, and spawning (e.g., Zelick et al., 1999; Fay, 2009). The most likely effects on fishes exposed to loud, intermittent, low-frequency sounds are behavioral responses (i.e., flight or avoidance). Short duration, sharp sounds (such as pile driving or air guns) can cause overt or subtle changes in fish behavior and local distribution. The reaction of fish to acoustic sources depends on the physiological state of PO 00000 Frm 00048 Fmt 4701 Sfmt 4702 the fish, past exposures, motivation (e.g., feeding, spawning, migration), and other environmental factors. Key impacts to fishes may include behavioral responses, hearing damage, barotrauma (pressure-related injuries), and mortality. Fishes, like other vertebrates, have a variety of different sensory systems to glean information from ocean around them (Astrup and Mohl, 1993; Astrup, 1999; Braun and Grande, 2008; Carroll et al., 2017; Hawkins and Johnstone, 1978; Ladich and Popper, 2004; Ladich and Schulz-Mirbach, 2016; Mann, 2016; Nedwell et al., 2004; Popper et al., 2003; Popper et al., 2005). Depending on their hearing anatomy and peripheral sensory structures, which vary among species, fishes hear sounds using pressure and particle motion sensitivity capabilities and detect the motion of surrounding water (Fay et al., 2008) (terrestrial vertebrates generally only detect pressure). Most marine fishes primarily detect particle motion using the inner ear and lateral line system, while some fishes possess additional morphological adaptations or specializations that can enhance their sensitivity to sound pressure, such as a gas-filled swim bladder (Braun and Grande, 2008; Popper and Fay, 2011). Hearing capabilities vary considerably between different fish species with data only available for just over 100 species out of the 34,000 marine and freshwater fish species (Eschmeyer and Fong, 2016). In order to better understand acoustic impacts on fishes, fish hearing groups are defined by species that possess a similar continuum of anatomical features which result in varying degrees of hearing sensitivity (Popper and Hastings, 2009a). There are four hearing groups defined for all fish species (modified from Popper et al., 2014) within this analysis and they include: Fishes without a swim bladder (e.g., flatfish, sharks, rays, etc.); fishes with a swim bladder not involved in hearing (e.g., salmon, cod, pollock, etc.); fishes with a swim bladder involved in hearing (e.g., sardines, anchovy, herring, etc.); and fishes with a swim bladder involved in hearing and high-frequency hearing (e.g., shad and menhaden). Most marine mammal fish prey species would not be likely to perceive or hear Navy mid- or high-frequency sonars. While hearing studies have not been done on sardines and northern anchovies, it would not be unexpected for them to possess hearing similarities to Pacific herring (up to 2–5 kHz) (Mann et al., 2005). Currently, less data are available to estimate the range of best sensitivity for fishes without a swim bladder. E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules In terms of physiology, multiple scientific studies have documented a lack of mortality or physiological effects to fish from exposure to low- and midfrequency sonar and other sounds (Halvorsen et al., 2012; J<rgensen et al., 2005; Juanes et al., 2017; Kane et al., 2010; Kvadsheim and Sevaldsen, 2005; Popper et al., 2007; Popper et al., 2016; Watwood et al., 2016). Techer et al. (2017) exposed carp in floating cages for up to 30 days to low-power 23 and 46 kHz sources without any significant physiological response. Other studies have documented either a lack of TTS in species whose hearing range cannot perceive Navy sonar, or for those species that could perceive sonar-like signals, any TTS experienced would be recoverable (Halvorsen et al., 2012; Ladich and Fay, 2013; Popper and Hastings, 2009a, 2009b; Popper et al., 2014; Smith, 2016). Only fishes that have specializations that enable them to hear sounds above about 2,500 Hz (2.5 kHz) such as herring (Halvorsen et al., 2012; Mann et al., 2005; Mann, 2016; Popper et al., 2014) would have the potential to receive TTS or exhibit behavioral responses from exposure to mid-frequency sonar. In addition, any sonar induced TTS to fish whose hearing range could perceive sonar would only occur in the narrow spectrum of the source (e.g., 3.5 kHz) compared to the fish’s total hearing range (e.g., 0.01 kHz to 5 kHz). Overall, Navy sonar sources are much narrower in terms of source frequency compared to a given fish species full hearing range (Halvorsen et al., 2012; J<rgensen et al., 2005; Juanes et al., 2017; Kane et al., 2010; Kvadsheim & Sevaldsen, 2005; Popper et al., 2007; Popper and Hawkins, 2016; Watwood et al., 2016). In terms of behavioral responses, Juanes et al. (2017) discuss the potential for negative impacts from anthropogenic soundscapes on fish, but the author’s focus was on broader based sounds such as ship and boat noise sources. Watwood et al. (2016) also documented no behavioral responses by reef fish after exposure to mid-frequency active sonar. Doksaeter et al. (2009; 2012) reported no behavioral responses to mid-frequency naval sonar by Atlantic herring; specifically, no escape reactions (vertically or horizontally) were observed in free swimming herring exposed to mid-frequency sonar transmissions. Based on these results (Doksaeter et al., 2009; Doksaeter et al., 2012; Sivle et al., 2012), Sivle et al. (2014) created a model in order to report on the possible population-level effects on Atlantic herring from active naval sonar. The authors concluded that the VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 use of naval sonar poses little risk to populations of herring regardless of season, even when the herring populations are aggregated and directly exposed to sonar. Finally, Bruintjes et al. (2016) commented that fish exposed to any short-term noise within their hearing range might initially startle, but would quickly return to normal behavior. Occasional behavioral reactions to intermittent explosions and impulsive sound sources are unlikely to cause long-term consequences for individual fish or populations. Fish that experience hearing loss as a result of exposure to explosions and impulsive sound sources may have a reduced ability to detect relevant sounds such as predators, prey, or social vocalizations. However, PTS has not been known to occur in fishes and any hearing loss in fish may be as temporary as the timeframe required to repair or replace the sensory cells that were damaged or destroyed (Popper et al., 2005; Popper et al., 2014; Smith et al., 2006). It is not known if damage to auditory nerve fibers could occur, and if so, whether fibers would recover during this process. It is also possible for fish to be injured or killed by an explosion in the immediate vicinity of the surface from dropped or fired ordnance, or near the bottom from shallow water bottomplaced underwater mine warfare detonations. Physical effects from pressure waves generated by underwater sounds (e.g., underwater explosions) could potentially affect fish within proximity of training or testing activities. SPLs of sufficient strength have been known to cause injury to fish and fish mortality (summarized in Popper et al., 2014). The shock wave from an underwater explosion is lethal to fish at close range, causing massive organ and tissue damage and internal bleeding (Keevin and Hempen, 1997). At greater distance from the detonation point, the extent of mortality or injury depends on a number of factors including fish size, body shape, orientation, and species (Keevin and Hempen, 1997; Wright, 1982). At the same distance from the source, larger fish are generally less susceptible to death or injury, elongated forms that are round in cross-section are less at risk than deep-bodied forms, and fish oriented sideways to the blast suffer the greatest impact (Edds-Walton and Finneran, 2006; O’Keeffe, 1984; O’Keeffe and Young, 1984; Wiley et al., 1981; Yelverton et al., 1975). Species with gas-filled organs are more susceptible to injury and mortality than those without them (Gaspin, 1975; Gaspin et al., 1976; Goertner et al., PO 00000 Frm 00049 Fmt 4701 Sfmt 4702 33961 1994). Barotrauma injuries have been documented during controlled exposure to impact pile driving (an impulsive noise source, as are explosives and air guns) (Halvorsen et al., 2012b; Casper et al., 2013). Fish not killed or driven from a location by an explosion might change their behavior, feeding pattern, or distribution. Changes in behavior of fish have been observed as a result of sound produced by explosives, with effect intensified in areas of hard substrate (Wright, 1982). However, Navy explosive use avoids hard substrate to the best extent practical during underwater detonations, or deep-water surface detonations. Stunning from pressure waves could also temporarily immobilize fish, making them more susceptible to predation. The abundances of various fish (and invertebrates) near the detonation point for explosives could be altered for a few hours before animals from surrounding areas repopulate the area. However, these populations would likely be replenished as waters near the detonation point are mixed with adjacent waters. Repeated exposure of individual fish to sounds from underwater explosions is not likely and exposures are expected to be short-term and localized. Long-term consequences for fish populations would not be expected. For fishes exposed to Navy sonar, there would be limited sonar use spread out in time and space across large offshore areas such that only small areas are actually ensonified (tens of miles) compared to the total life history distribution of fish prey species. There would be no probability for mortality or physical injury from sonar, and for most species, no or little potential for hearing or behavioral effects, except to a few select fishes with hearing specializations (e.g., herring) that could perceive mid-frequency sonar. Training and testing exercises involving explosions are dispersed in space and time; therefore, repeated exposure of individual fishes are unlikely. Mortality and injury effects to fishes from explosives would be localized around the area of a given in-water explosion, but only if individual fish and the explosive (and immediate pressure field) were co-located at the same time. Fishes deeper in the water column or on the bottom would not be affected by water surface explosions. Repeated exposure of individual fish to sound and energy from underwater explosions is not likely given fish movement patterns, especially schooling prey species. Most acoustic effects, if any, are expected to be short-term and localized. E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33962 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Long-term consequences for fish populations, including key prey species within the NWTT Study Area, would not be expected. Vessels and in-water devices do not normally collide with adult fish, most of which can detect and avoid them. Exposure of fishes to vessel strike stressors is limited to those fish groups that are large, slow-moving, and may occur near the surface, such as ocean sunfish, whale sharks, basking sharks, and manta rays. These species are distributed widely in offshore portions of the NWTT Study Area. Any isolated cases of a Navy vessel striking an individual could injure that individual, impacting the fitness of an individual fish. Vessel strikes would not pose a risk to most of the other marine fish groups, because many fish can detect and avoid vessel movements, making strikes rare and allowing the fish to return to their normal behavior after the ship or device passes. As a vessel approaches a fish, they could have a detectable behavioral or physiological response (e.g., swimming away and increased heart rate) as the passing vessel displaces them. However, such reactions are not expected to have lasting effects on the survival, growth, recruitment, or reproduction of these marine fish groups at the population level and therefore would not have an impact on marine mammal species as prey items. In addition to fish, prey sources such as marine invertebrates could potentially be impacted by sound stressors as a result of the proposed activities. However, most marine invertebrates’ ability to sense sounds is very limited. In most cases, marine invertebrates would not respond to impulsive and non-impulsive sounds, although they may detect and briefly respond to nearby low-frequency sounds. These short-term responses would likely be inconsequential to invertebrate populations. Invertebrates appear to be able to detect sounds (Pumphrey, 1950; Frings and Frings, 1967) and are most sensitive to low-frequency sounds (Packard et al., 1990; Budelmann and Williamson, 1994; Lovell et al., 2005; Mooney et al., 2010). Data on response of invertebrates such as squid, another marine mammal prey species, to anthropogenic sound is more limited (de Soto, 2016; Sole et al., 2017b). Data suggest that cephalopods are capable of sensing the particle motion of sounds and detect low frequencies up to 1–1.5 kHz, depending on the species, and so are likely to detect air gun noise (Kaifu et al., 2008; Hu et al., 2009; Mooney et al., 2010; Samson et al., 2014). Sole et al. (2017b) reported physiological injuries to VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 cuttlefish in cages placed at-sea when exposed during a controlled exposure experiment to low-frequency sources (315 Hz, 139 to 142 dB re: 1 mPa2 and 400 Hz, 139 to 141 dB re: 1 mPa2). Fewtrell and McCauley (2012) reported squids maintained in cages displayed startle responses and behavioral changes when exposed to seismic air gun sonar (136–162 re: 1 mPa2·s). However, the sources Sole et al. (2017a) and Fewtrell and McCauley (2012) used are not similar and were much lower than typical Navy sources within the NWTT Study Area. Nor do the studies address the issue of individual displacement outside of a zone of impact when exposed to sound. Cephalopods have a specialized sensory organ inside the head called a statocyst that may help an animal determine its position in space (orientation) and maintain balance (Budelmann, 1992). Packard et al. (1990) showed that cephalopods were sensitive to particle motion, not sound pressure, and Mooney et al. (2010) demonstrated that squid statocysts act as an accelerometer through which particle motion of the sound field can be detected. Auditory injuries (lesions occurring on the statocyst sensory hair cells) have been reported upon controlled exposure to low-frequency sounds, suggesting that cephalopods are particularly sensitive to low-frequency sound (Andre et al., 2011; Sole et al., 2013). Behavioral responses, such as inking and jetting, have also been reported upon exposure to lowfrequency sound (McCauley et al., 2000b; Samson et al., 2014). Squids, like most fish species, are likely more sensitive to low frequency sounds, and may not perceive mid- and highfrequency sonars such as Navy sonars. Cumulatively for squid as a prey species, individual and population impacts from exposure to Navy sonar and explosives, like fish, are not likely to be significant, and explosive impacts would be short-term and localized. Explosions could kill or injure nearby marine invertebrates. Vessels also have the potential to impact marine invertebrates by disturbing the water column or sediments, or directly striking organisms (Bishop, 2008). The propeller wash (water displaced by propellers used for propulsion) from vessel movement and water displaced from vessel hulls can potentially disturb marine invertebrates in the water column and is a likely cause of zooplankton mortality (Bickel et al., 2011). The localized and short-term exposure to explosions or vessels could displace, injure, or kill zooplankton, invertebrate eggs or larvae, and macro- PO 00000 Frm 00050 Fmt 4701 Sfmt 4702 invertebrates. However, mortality or long-term consequences for a few animals is unlikely to have measurable effects on overall populations. Longterm consequences to marine invertebrate populations would not be expected as a result of exposure to sounds of vessels in the NWTT Study Area. Impacts to benthic communities from impulsive sound generated by active acoustic sound sources are not well documented. (e.g., Andriguetto-Filho et al., 2005; Payne et al., 2007; 2008; Boudreau et al., 2009). There are no published data that indicate whether temporary or permanent threshold shifts, auditory masking, or behavioral effects occur in benthic invertebrates (Hawkins et al., 2014) and some studies showed no short-term or long-term effects of air gun exposure (e.g., Andriguetto-Filho et al., 2005; Payne et al., 2007; 2008; Boudreau et al., 2009). Exposure to air gun signals was found to significantly increase mortality in scallops, in addition to causing significant changes in behavioral patterns during exposure (Day et al., 2017). However, the authors state that the observed levels of mortality were not beyond naturally occurring rates. Explosions and pile driving could potentially kill or injure nearby marine invertebrates; however, mortality or long-term consequences for a few animals is unlikely to have measurable effects on overall populations. There is little information concerning potential impacts of noise on zooplankton populations. However, one recent study (McCauley et al., 2017) investigated zooplankton abundance, diversity, and mortality before and after exposure to air gun noise, finding that the mortality rate for zooplankton after airgun exposure was two to three times more compared with controls for all taxa. The majority of taxa present were copepods and cladocerans; for these taxa, the range within which effects on abundance were detected was up to approximately 1.2 km. In order to have significant impacts on r-selected species such as plankton, the spatial or temporal scale of impact must be large in comparison with the ecosystem concerned (McCauley et al., 2017). Therefore, the large scale of effect observed here is of concern— particularly where repeated noise exposure is expected—and further study is warranted. Military expended materials resulting from training and testing activities could potentially result in minor longterm changes to benthic habitat, however the impacts of small amount of expended materials are unlikely to have E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 measurable effects on overall populations. Military expended materials may be colonized over time by benthic organisms that prefer hard substrate and would provide structure that could attract some species of fish or invertebrates. Overall, the combined impacts of sound exposure, explosions, vessel strikes, and military expended materials resulting from the proposed activities would not be expected to have measurable effects on populations of marine mammal prey species. Prey species exposed to sound might move away from the sound source, experience TTS, experience masking of biologically relevant sounds, or show no obvious direct effects. Mortality from decompression injuries is possible in close proximity to a sound, but only limited data on mortality in response to air gun noise exposure are available (Hawkins et al., 2014). The most likely impacts for most prey species in a given area would be temporary avoidance of the area. Surveys using towed air gun arrays move through an area relatively quickly, limiting exposure to multiple impulsive sounds. In all cases, sound levels would return to ambient once a survey ends and the noise source is shut down and, when exposure to sound ends, behavioral and/or physiological responses are expected to end relatively quickly (McCauley et al., 2000b). The duration of fish avoidance of a given area after survey effort stops is unknown, but a rapid return to normal recruitment, distribution, and behavior is anticipated. While the potential for disruption of spawning aggregations or schools of important prey species can be meaningful on a local scale, the mobile and temporary nature of most surveys and the likelihood of temporary avoidance behavior suggest that impacts would be minor. Long-term consequences to marine invertebrate populations would not be expected as a result of exposure to sounds or vessels in the NWTT Study Area. Acoustic Habitat Acoustic habitat is the soundscape which encompasses all of the sound present in a particular location and time, as a whole when considered from the perspective of the animals experiencing it. Animals produce sound for, or listen for sounds produced by, conspecifics (communication during feeding, mating, and other social activities), other animals (finding prey or avoiding predators), and the physical environment (finding suitable habitats, navigating). Together, sounds made by animals and the geophysical environment (e.g., produced by VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 earthquakes, lightning, wind, rain, waves) make up the natural contributions to the total acoustics of a place. These acoustic conditions, termed acoustic habitat, are one attribute of an animal’s total habitat. Soundscapes are also defined by, and acoustic habitat influenced by, the total contribution of anthropogenic sound. This may include incidental emissions from sources such as vessel traffic or may be intentionally introduced to the marine environment for data acquisition purposes (as in the use of air gun arrays) or for Navy training and testing purposes (as in the use of sonar and explosives and other acoustic sources). Anthropogenic noise varies widely in its frequency, content, duration, and loudness, and these characteristics greatly influence the potential habitatmediated effects to marine mammals (please also see the previous discussion on ‘‘Masking’’), which may range from local effects for brief periods of time to chronic effects over large areas and for long durations. Depending on the extent of effects to habitat, animals may alter their communications signals (thereby potentially expending additional energy) or miss acoustic cues (either conspecific or adventitious). Problems arising from a failure to detect cues are more likely to occur when noise stimuli are chronic and overlap with biologically relevant cues used for communication, orientation, and predator/prey detection (Francis and Barber, 2013). For more detail on these concepts see, e.g., Barber et al., 2009; Pijanowski et al., 2011; Francis and Barber, 2013; Lillis et al., 2014. The term ‘‘listening area’’ refers to the region of ocean over which sources of sound can be detected by an animal at the center of the space. Loss of communication space concerns the area over which a specific animal signal (used to communicate with conspecifics in biologically important contexts such as foraging or mating) can be heard, in noisier relative to quieter conditions (Clark et al., 2009). Lost listening area concerns the more generalized contraction of the range over which animals would be able to detect a variety of signals of biological importance, including eavesdropping on predators and prey (Barber et al., 2009). Such metrics do not, in and of themselves, document fitness consequences for the marine animals that live in chronically noisy environments. Long-term populationlevel consequences mediated through changes in the ultimate survival and reproductive success of individuals are difficult to study, and particularly so underwater. However, it is increasingly PO 00000 Frm 00051 Fmt 4701 Sfmt 4702 33963 well documented that aquatic species rely on qualities of natural acoustic habitats, with researchers quantifying reduced detection of important ecological cues (e.g., Francis and Barber, 2013; Slabbekoorn et al., 2010) as well as survivorship consequences in several species (e.g., Simpson et al., 2014; Nedelec et al., 2015). The sounds produced during training and testing activities can be widely dispersed or concentrated in small areas for varying periods. Sound produced from training and testing activities in the NWTT Study Area is temporary and transitory. Any anthropogenic noise attributed to training and testing activities in the NWTT Study Area would be temporary and the affected area would be expected to immediately return to the original state when these activities cease. Water Quality Training and testing activities may introduce water quality constituents into the water column. Based on the analysis of the 2019 NWTT DSEIS/OEIS, military expended materials (e.g., undetonated explosive materials) would be released in quantities and at rates that would not result in a violation of any water quality standard or criteria. NMFS has reviewed this analysis and concurs that it reflects the best available science. High-order explosions consume most of the explosive material, creating typical combustion products. For example, in the case of Royal Demolition Explosive, 98 percent of the products are common seawater constituents and the remainder is rapidly diluted below threshold effect level. Explosion by-products associated with high order detonations present no secondary stressors to marine mammals through sediment or water. However, low order detonations and unexploded ordnance present elevated likelihood of impacts on marine mammals. Indirect effects of explosives and unexploded ordnance to marine mammals via sediment is possible in the immediate vicinity of the ordnance. Degradation products of Royal Demolition Explosive are not toxic to marine organisms at realistic exposure levels (Rosen and Lotufo, 2010). Relatively low solubility of most explosives and their degradation products means that concentrations of these contaminants in the marine environment are relatively low and readily diluted. Furthermore, while explosives and their degradation products were detectable in marine sediment approximately 6–12 in (0.15– 0.3 m) away from degrading ordnance, the concentrations of these compounds E:\FR\FM\02JNP2.SGM 02JNP2 33964 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 were not statistically distinguishable from background beyond 3–6 ft (1–2 m) from the degrading ordnance. Taken together, it is possible that marine mammals could be exposed to degrading explosives, but it would be within a very small radius of the explosive (1–6 ft (0.3–2 m)). Equipment used by the Navy within the NWTT Study Area, including ships and other marine vessels, aircraft, and other equipment, are also potential sources of by-products. All equipment is properly maintained in accordance with applicable Navy and legal requirements. All such operating equipment meets Federal water quality standards, where applicable. Estimated Take of Marine Mammals This section indicates the number of takes that NMFS is proposing to authorize, which is based on the amount of take that NMFS anticipates could occur or the maximum amount that is reasonably likely to occur, depending on the type of take and the methods used to estimate it, as described in detail below. NMFS coordinated closely with the Navy in the development of their incidental take application, and preliminarily agrees that the methods the Navy has put forth described herein to estimate take (including the model, thresholds, and density estimates), and the resulting numbers estimated for authorization, are appropriate and based on the best available science. Takes would be predominantly in the form of harassment, but a small number of mortalities are also possible. For a military readiness activity, the MMPA defines ‘‘harassment’’ as (i) Any act that injures or has the significant potential to injure a marine mammal or marine mammal stock in the wild (Level A Harassment); or (ii) Any act that disturbs or is likely to disturb a marine mammal or marine mammal stock in the wild by causing disruption of natural behavioral patterns, including, but not limited to, migration, surfacing, nursing, breeding, feeding, or sheltering, to a point where such behavioral patterns are abandoned or significantly altered (Level B Harassment). Proposed authorized takes would primarily be in the form of Level B harassment, as use of the acoustic and explosive sources (i.e., sonar and explosives) is most likely to result in the disruption of natural behavioral patterns to a point where they are abandoned or significantly altered (as defined specifically at the beginning of this section, but referred to generally as VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 behavioral disruption) or TTS for marine mammals. There is also the potential for Level A harassment, in the form of auditory injury to result from exposure to the sound sources utilized in training and testing activities. Lastly, no more than three serious injuries or mortalities total (over the seven-year period) of large whales could potentially occur through vessel collisions. Although we analyze the impacts of these potential serious injuries or mortalities that are proposed for authorization, the proposed mitigation and monitoring measures are expected to minimize the likelihood (i.e., further lower the already low probability) that ship strike (and the associated serious injury or mortality) would occur. Generally speaking, for acoustic impacts NMFS estimates the amount and type of harassment by considering: (1) Acoustic thresholds above which NMFS believes the best available science indicates marine mammals will be taken by Level B harassment (in this case, as defined in the military readiness definition of Level B harassment included above) or incur some degree of temporary or permanent hearing impairment; (2) the area or volume of water that will be ensonified above these levels in a day or event; (3) the density or occurrence of marine mammals within these ensonified areas; and (4) the number of days of activities or events. Acoustic Thresholds Using the best available science, NMFS, in coordination with the Navy, has established acoustic thresholds that identify the most appropriate received level of underwater sound above which marine mammals exposed to these sound sources could be reasonably expected to experience a disruption in behavior patterns to a point where they are abandoned or significantly altered, or to incur TTS (equated to Level B harassment) or PTS of some degree (equated to Level A harassment). Thresholds have also been developed to identify the pressure levels above which animals may incur non-auditory injury from exposure to pressure waves from explosive detonation. Despite the quickly evolving science, there are still challenges in quantifying expected behavioral responses that qualify as take by Level B harassment, especially where the goal is to use one or two predictable indicators (e.g., received level and distance) to predict responses that are also driven by PO 00000 Frm 00052 Fmt 4701 Sfmt 4702 additional factors that cannot be easily incorporated into the thresholds (e.g., context). So, while the behavioral Level B harassment thresholds have been refined to better consider the best available science (e.g., incorporating both received level and distance), they also still have some built-in conservative factors to address the challenge noted. For example, while duration of observed responses in the data are now considered in the thresholds, some of the responses that are informing take thresholds are of a very short duration, such that it is possible some of these responses might not always rise to the level of disrupting behavior patterns to a point where they are abandoned or significantly altered. We describe the application of this Level B harassment threshold as identifying the maximum number of instances in which marine mammals could be reasonably expected to experience a disruption in behavior patterns to a point where they are abandoned or significantly altered. In summary, we believe these behavioral Level B harassment thresholds are the most appropriate method for predicting behavioral Level B harassment given the best available science and the associated uncertainty. Hearing Impairment (TTS/PTS) and Tissue Damage and Mortality NMFS’ Acoustic Technical Guidance (NMFS, 2018) identifies dual criteria to assess auditory injury (Level A harassment) to five different marine mammal groups (based on hearing sensitivity) as a result of exposure to noise from two different types of sources (impulsive or non-impulsive). The Acoustic Technical Guidance also identifies criteria to predict TTS, which is not considered injury and falls into the Level B harassment category. The Navy’s planned activity includes the use of non-impulsive (sonar) and impulsive (explosives) sources. These thresholds (Tables 10 and 11) were developed by compiling and synthesizing the best available science and soliciting input multiple times from both the public and peer reviewers. The references, analysis, and methodology used in the development of the thresholds are described in Acoustic Technical Guidance, which may be accessed at: https:// www.fisheries.noaa.gov/national/ marine-mammal-protection/marinemammal-acoustic-technical-guidance. E:\FR\FM\02JNP2.SGM 02JNP2 33965 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 10—ACOUSTIC THRESHOLDS IDENTIFYING THE ONSET OF TTS AND PTS FOR NON-IMPULSIVE SOUND SOURCES BY FUNCTIONAL HEARING GROUPS Non-impulsive Functional hearing group TTS threshold SEL (weighted) Low-Frequency Cetaceans .......................................................................................................................... Mid-Frequency Cetaceans ........................................................................................................................... High-Frequency Cetaceans ......................................................................................................................... Phocid Pinnipeds (Underwater) ................................................................................................................... Otarid Pinnipeds (Underwater) .................................................................................................................... PTS threshold SEL (weighted) 179 178 153 181 199 199 198 173 201 219 Note: SEL thresholds in dB re: 1 μPa2s. Based on the best available science, the Navy (in coordination with NMFS) used the acoustic and pressure thresholds indicated in Table 11 to predict the onset of TTS, PTS, tissue damage, and mortality for explosives (impulsive) and other impulsive sound sources. TABLE 11—ONSET OF TTS, PTS, TISSUE DAMAGE, AND MORTALITY THRESHOLDS FOR MARINE MAMMALS FOR EXPLOSIVES Functional hearing group Low-frequency cetaceans. Mid-frequency cetaceans. High-frequency cetaceans. Phocidae .................. Otariidae .................. Species Weighted onset TTS 1 Weighted onset PTS All mysticetes ........ 168 dB SEL or 213 dB Peak SPL. 170 dB SEL or 224 dB Peak SPL. 183 dB SEL or 219 dB Peak SPL. 185 dB SEL or 230 dB Peak SPL. 237 dB Peak SPL 140 dB SEL or 196 dB Peak SPL. 170 dB SEL or 212 dB Peak SPL. 155 dB SEL or 202 dB Peak SPL. 185 dB SEL or 218 dB Peak SPL. 237 dB Peak SPL. 188 dB SEL or 226 dB Peak SPL. 203 dB SEL or 232 dB Peak SPL. 237 dB Peak SPL. Most delphinids, medium and large toothed whales. Porpoises and Kogia spp. Harbor seal, Hawaiian monk seal, Northern elephant seal. California sea lion, Guadalupe fur seal, Northern fur seal. Mean onset slight GI tract injury Mean onset slight lung injury Equation 1 ...... Mean onset mortality Equation 2. 237 dB Peak SPL. 237 dB Peak SPL. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Notes: Equation 1: 47.5M1/3 (1+[DRm/10.1])1/6 Pa-sec. Equation 2: 103M1/3 (1+[DRm/10.1])1/6 Pa-sec. M = mass of the animals in kg. DRm = depth of the receiver (animal) in meters. SPL = sound pressure level. 1 Peak thresholds are unweighted. The criteria used to assess the onset of TTS and PTS due to exposure to sonars (non-impulsive, see Table 10 above) are discussed further in the Navy’s rulemaking/LOA application (see Hearing Loss from Sonar and Other Transducers in Chapter 6, Section 6.4.2.1, Methods for Analyzing Impacts from Sonars and Other Transducers). Refer to the ‘‘Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III)’’ report (U.S. Department of the Navy, 2017c) for detailed information on how the criteria and thresholds were derived. Nonauditory injury (i.e., other than PTS) and mortality from sonar and other transducers is so unlikely as to be discountable under normal conditions VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 for the reasons explained under the Potential Effects of Specified Activities on Marine Mammals and Their Habitat section—Acoustically Mediated Bubble Growth and other Pressure-related Injury and is therefore not considered further in this analysis. Behavioral Harassment Though significantly driven by received level, the onset of Level B harassment by behavioral disturbance from anthropogenic noise exposure is also informed to varying degrees by other factors related to the source (e.g., frequency, predictability, duty cycle), the environment (e.g., bathymetry), and the receiving animals (hearing, motivation, experience, demography, behavioral context) and can be difficult PO 00000 Frm 00053 Fmt 4701 Sfmt 4702 to predict (Ellison et al., 2011; Southall et al., 2007). Based on what the available science indicates and the practical need to use thresholds based on a factor, or factors, that are both predictable and measurable for most activities, NMFS uses generalized acoustic thresholds based primarily on received level (and distance in some cases) to estimate the onset of Level B behavioral harassment. Sonar As noted above, the Navy coordinated with NMFS to develop Level B behavioral harassment thresholds specific to their military readiness activities utilizing active sonar. These behavioral response thresholds are used to estimate the number of animals that E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33966 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules may exhibit a behavioral response that rises to the level of a take when exposed to sonar and other transducers. The way the criteria were derived is discussed in detail in the ‘‘Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III)’’ report (U.S. Department of the Navy, 2017c). Developing the Level B harassment behavioral criteria involved multiple steps. All peer-reviewed published behavioral response studies conducted both in the field and on captive animals were examined in order to understand the breadth of behavioral responses of marine mammals to sonar and other transducers. NMFS has carefully reviewed the Navy’s Level B behavioral thresholds and establishment of cutoff distances for the species, and agrees that it is the best available science and is the appropriate method to use at this time for determining impacts to marine mammals from sonar and other transducers and for calculating take and to support the determinations made in this proposed rule. As discussed above, marine mammal responses to sound (some of which are considered disturbances that rise to the level of a take) are highly variable and context specific, i.e., they are affected by differences in acoustic conditions; differences between species and populations; differences in gender, age, reproductive status, or social behavior; and other prior experience of the individuals. This means that there is support for considering alternative approaches for estimating Level B behavioral harassment. Although the statutory definition of Level B harassment for military readiness activities means that a natural behavior pattern of a marine mammal is significantly altered or abandoned, the current state of science for determining those thresholds is somewhat unsettled. In its analysis of impacts associated with sonar acoustic sources (which was coordinated with NMFS), the Navy used an updated conservative approach that likely overestimates the number of takes by Level B harassment due to behavioral disturbance and response. Many of the behavioral responses identified using the Navy’s quantitative analysis are most likely to be of moderate severity as described in the Southall et al. (2007) behavioral response severity scale. These ‘‘moderate’’ severity responses were considered significant if they were sustained for the duration of the exposure or longer. Within the Navy’s quantitative analysis, many reactions are predicted from exposure to sound that may exceed an animal’s Level B behavioral harassment threshold for only a single exposure (a few seconds) VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 to several minutes, and it is likely that some of the resulting estimated behavioral responses that are counted as Level B harassment would not constitute ‘‘significantly altering or abandoning natural behavioral patterns.’’ The Navy and NMFS have used the best available science to address the challenging differentiation between significant and non-significant behavioral reactions (i.e., whether the behavior has been abandoned or significantly altered such that it qualifies as harassment), but have erred on the cautious side where uncertainty exists (e.g., counting these lower duration reactions as take), which likely results in some degree of overestimation of behavioral Level B harassment. We consider application of this behavioral Level B harassment threshold, therefore, as identifying the maximum number of instances in which marine mammals could be reasonably expected to experience a disruption in behavior patterns to a point where they are abandoned or significantly altered (i.e., Level B harassment). Because this is the most appropriate method for estimating Level B harassment given the best available science and uncertainty on the topic, it is these numbers of Level B harassment by behavioral disturbance that are analyzed in the Preliminary Analysis and Negligible Impact Determination section and would be authorized. In the Navy’s acoustic impact analyses during Phase II (the previous phase of Navy testing and training, 2013–2018, see also Navy’s ‘‘Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis Technical Report’’, 2012), the likelihood of behavioral Level B harassment in response to sonar and other transducers was based on a probabilistic function (termed a behavioral response function—BRF), that related the likelihood (i.e., probability) of a behavioral response (at the level of a Level B harassment) to the received SPL. The BRF was used to estimate the percentage of an exposed population that is likely to exhibit Level B harassment due to altered behaviors or behavioral disturbance at a given received SPL. This BRF relied on the assumption that sound poses a negligible risk to marine mammals if they are exposed to SPL below a certain ‘‘basement’’ value. Above the basement exposure SPL, the probability of a response increased with increasing SPL. Two BRFs were used in Navy acoustic impact analyses: BRF1 for mysticetes and BRF2 for other species. BRFs were not used for beaked whales during PO 00000 Frm 00054 Fmt 4701 Sfmt 4702 Phase II analyses. Instead, a step function at an SPL of 140 dB re: 1 mPa was used for beaked whales as the threshold to predict Level B harassment by behavioral disturbance. Developing the behavioral Level B harassment criteria for Phase III (the current phase of Navy training and testing activities) involved multiple steps: all available behavioral response studies conducted both in the field and on captive animals were examined to understand the breadth of behavioral responses of marine mammals to sonar and other transducers (See also Navy’s ‘‘Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III) Technical Report’’, 2017). Six behavioral response field studies with observations of 14 different marine mammal species reactions to sonar or sonar-like signals and 6 captive animal behavioral studies with observations of 8 different species reactions to sonar or sonar-like signals were used to provide a robust data set for the derivation of the Navy’s Phase III marine mammal behavioral response criteria. All behavioral response research that has been published since the derivation of the Navy’s Phase III criteria (c.a. December 2016) has been examined and is consistent with the current behavioral response functions. Marine mammal species were placed into behavioral criteria groups based on their known or suspected behavioral sensitivities to sound. In most cases these divisions were driven by taxonomic classifications (e.g., mysticetes, pinnipeds). The data from the behavioral studies were analyzed by looking for significant responses, or lack thereof, for each experimental session. The Navy used cutoff distances beyond which the potential of significant behavioral responses (and therefore Level B harassment) is considered to be unlikely (see Table 12 below). These distances were determined by examining all available published field observations of behavioral reactions to sonar or sonarlike signals that included the distance between the sound source and the marine mammal. The longest distance, rounded up to the nearest 5-km increment, was chosen as the cutoff distance for each behavioral criteria group (i.e. odontocetes, mysticetes, and beaked whales). For animals within the cutoff distance, behavioral response functions for each behavioral criteria group based on a received SPL as presented in Chapter 6, Section 6.4.2.1 (Methods for Analyzing Impacts from Sonars and other Transducers) of the Navy’s rulemaking/LOA application were used to predict the probability of E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 a potential significant behavioral response. For training and testing events that contain multiple platforms or tactical sonar sources that exceed 215 dB re: 1 mPa at 1 m, this cutoff distance is substantially increased (i.e., doubled) from values derived from the literature. The use of multiple platforms and intense sound sources are factors that probably increase responsiveness in marine mammals overall (however, we note that helicopter dipping sonars were considered in the intense sound source group, despite lower source levels, because of data indicating that marine mammals are sometimes more responsive to the less predictable employment of this source). There are currently few behavioral observations under these circumstances; therefore, the Navy conservatively predicted significant behavioral responses that would rise to Level B harassment at farther ranges than shown in Table 12, versus less intense events. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 33967 received level exceeds the distance cutoff range for a particular hearing group and therefore are not included in the estimated take. See Chapter 6, Section 6.4.2.1 (Methods for Analyzing Impacts from Sonars and Other Transducers) of the Navy’s rulemaking/ LOA application for further details on the derivation and use of the behavioral response functions, thresholds, and the Moderate High cutoff distances to identify takes by SL/single SL/multiLevel B harassment, which were Criteria platform platform group cutoff cutoff coordinated with NMFS. As noted distance distance previously, NMFS carefully reviewed, (km) (km) and contributed to, the Navy’s proposed behavioral Level B harassment Odontocetes .......... 10 20 thresholds and cutoff distances for each Pinnipeds .. 5 10 behavioral criteria group, and agrees Mysticetes 10 20 that these methods represent the best Beaked available science at this time for Whales .. 25 50 determining impacts to marine Harbor Porpoise ...... 20 40 mammals from sonar and other transducers. Notes: dB re: 1 μPa at 1 m = decibels refTable 13 illustrates the maximum erenced to 1 micropascal at 1 meter, km = kilometer, SL = source level. likely percentage of exposed individuals taken at the indicated received level and The range to received sound levels in associated range (in which marine 6-dB steps from five representative mammals would be reasonably expected sonar bins and the percentage of to experience a disruption in behavior animals that may be taken by Level B patterns to a point where they are harassment under each behavioral abandoned or significantly altered) for response function are shown in Tables low-frequency active sonar (LFAS). 13 through 17. Cells are shaded if the mean range value for the specified BILLING CODE 3510–22–P TABLE 12—CUTOFF DISTANCES FOR MODERATE SOURCE LEVEL, SINGLE PLATFORM TRAINING AND TESTING EVENTS AND FOR ALL OTHER EVENTS WITH MULTIPLE PLATFORMS OR SONAR WITH SOURCE LEVELS AT OR EXCEEDING 215 dB RE: 1 μPa AT 1 m. PO 00000 Frm 00055 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 Tables 14 through 16 identify the maximum likely percentage of exposed individuals taken at the indicated VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 received level and associated range for mid-frequency active sonar (MFAS). PO 00000 Frm 00056 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.014</GPH> 33968 VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00057 Fmt 4701 Sfmt 4725 E:\FR\FM\02JNP2.SGM 02JNP2 33969 EP02JN20.003</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules VerDate Sep<11>2014 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00058 Fmt 4701 Sfmt 4725 E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.004</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 33970 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 associated range for high-frequency active sonar (HFAS). PO 00000 Frm 00059 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.005</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Table 17 identifies the maximum likely percentage of exposed individuals taken at the indicated received level and 33971 33972 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules BILLING CODE 3510–22–C Explosives Phase III explosive criteria for behavioral Level B harassment thresholds for marine mammals is the functional hearing groups’ TTS onset threshold (in SEL) minus 5 dB (see Table 18 below and Table 11 for the TTS thresholds for explosives) for events that contain multiple impulses from explosives underwater. This was the same approach as taken in Phase II for explosive analysis. See the ‘‘Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III)’’ report (U.S. Department of the Navy, 2017c) for detailed information on how the criteria and thresholds were derived. NMFS continues to concur that this approach represents the best available science for determining impacts to marine mammals from explosives. TABLE 18—BEHAVIORAL LEVEL B HARASSMENT THRESHOLDS FOR EXPLOSIVES FOR MARINE MAMMALS Medium Underwater Underwater Underwater Underwater Underwater SEL (weighted) Functional hearing group ............................................... ............................................... ............................................... ............................................... ............................................... Low-frequency cetaceans ............................................................................................ Mid-frequency cetaceans ............................................................................................. High-frequency cetaceans ........................................................................................... Phocids ......................................................................................................................... Otariids ......................................................................................................................... 163 165 135 165 183 Navy’s Acoustic Effects Model The Navy’s Acoustic Effects Model calculates sound energy propagation from sonar and other transducers and explosives during naval activities and the sound received by animat dosimeters. Animat dosimeters are VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 virtual representations of marine mammals distributed in the area around the modeled naval activity and each dosimeter records its individual sound ‘‘dose.’’ The model bases the distribution of animats over the NWTT Study Area on the density values in the Navy Marine Species Density Database PO 00000 Frm 00060 Fmt 4701 Sfmt 4702 and distributes animats in the water column proportional to the known time that species spend at varying depths. The model accounts for environmental variability of sound propagation in both distance and depth when computing the sound level received by the animats. The model E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.006</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Note: Weighted SEL thresholds in dB re: 1 μPa2s underwater. 33973 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules conducts a statistical analysis based on multiple model runs to compute the estimated effects on animals. The number of animats that exceed the thresholds for effects is tallied to provide an estimate of the number of marine mammals that could be affected. Assumptions in the Navy model intentionally err on the side of overestimation when there are unknowns. Naval activities are modeled as though they would occur regardless of proximity to marine mammals, meaning that no mitigation is considered (i.e., no power down or shut down modeled) and without any avoidance of the activity by the animal. The final step of the quantitative analysis of acoustic effects is to consider the implementation of mitigation and the possibility that marine mammals would avoid continued or repeated sound exposures. For more information on this process, see the discussion in the Take Requests subsection below. Many explosions from ordnance such as bombs and missiles actually occur upon impact with above-water targets. However, for this analysis, sources such as these were modeled as exploding underwater. This overestimates the amount of explosive and acoustic energy entering the water. The model estimates the impacts caused by individual training and testing exercises. During any individual modeled event, impacts to individual animats are considered over 24-hour periods. The animats do not represent actual animals, but rather they represent a distribution of animals based on density and abundance data, which allows for a statistical analysis of the number of instances that marine mammals may be exposed to sound levels resulting in an effect. Therefore, the model estimates the number of instances in which an effect threshold was exceeded over the course of a year, but does not estimate the number of individual marine mammals that may be impacted over a year (i.e., some marine mammals could be impacted several times, while others would not experience any impact). A detailed explanation of the Navy’s Acoustic Effects Model is provided in the technical report ‘‘Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and Analytical Approach for Phase III Training and Testing’’ (U.S. Department of the Navy, 2018). Sonar and Other Transducers and Explosives Range to Effects The following section provides range to effects for sonar and other active acoustic sources as well as explosives to specific acoustic thresholds determined using the Navy Acoustic Effects Model. Marine mammals exposed within these ranges for the shown duration are predicted to experience the associated effect. Range to effects is important information in not only predicting acoustic impacts, but also in verifying the accuracy of model results against real-world situations and determining adequate mitigation ranges to avoid higher level effects, especially physiological effects to marine mammals. Sonar The ranges to received sound levels in 6-dB steps from five representative sonar bins and the percentage of the total number of animals that may exhibit a significant behavioral response (and therefore Level B harassment) under each behavioral response function are shown in Tables 13 through 17 above. See Chapter 6, Section 6.4.2.1 (Methods for Analyzing Impacts from Sonars and Other Transducers) of the Navy’s rulemaking/LOA application for additional details on the derivation and use of the behavioral response functions, thresholds, and the cutoff distances that are used to identify Level B behavioral harassment. The ranges to PTS for five representative sonar systems for an exposure of 30 seconds is shown in Table 19 relative to the marine mammal’s functional hearing group. This period (30 seconds) was chosen based on examining the maximum amount of time a marine mammal would realistically be exposed to levels that could cause the onset of PTS based on platform (e.g., ship) speed and a nominal animal swim speed of approximately 1.5 m per second. The ranges provided in the table include the average range to PTS, as well as the range from the minimum to the maximum distance at which PTS is possible for each hearing group. TABLE 19—RANGE TO PERMANENT THRESHOLD SHIFT (METERS) FOR FIVE REPRESENTATIVE SONAR SYSTEMS Approximate PTS (30 seconds) ranges (meters) 1 Hearing group Sonar bin HF4 High-frequency cetaceans ................................................... Low-frequency cetaceans .................................................... Mid-frequency cetaceans ..................................................... Otariids ................................................................................. Phocids ................................................................................ Sonar bin LF4 38 (22–85) 0 (0–0) 1 (0–3) 0 (0–0) 0 (0–0) 0 2 0 0 0 (0–0) (1–3) (0–0) (0–0) (0–0) Sonar bin MF1 Sonar bin MF4 Sonar bin MF5 195 (80–330) 67 (60–110) 16 (16–19) 6 (6–6) 46 (45–75) 30 (30–40) 15 (15–17) 3 (3–3) 0 (0–0) 11 (11–12) 9 (8–11) 0 (0–0) 0 (0–0) 0 (0–0) 0 (0–0) 1 PTS ranges extend from the sonar or other transducer sound source to the indicated distance. The average range to PTS is provided as well as the range from the estimated minimum to the maximum range to PTS in parentheses. Notes: HF = high-frequency, LF = low-frequency, MF = mid-frequency, PTS = permanent threshold shift. khammond on DSKJM1Z7X2PROD with PROPOSALS2 The tables below illustrate the range to TTS for 1, 30, 60, and 120 seconds from five representative sonar systems (see Tables 20 through 24). TABLE 20—RANGES TO TEMPORARY THRESHOLD SHIFT (METERS) FOR SONAR BIN LF4 OVER A REPRESENTATIVE RANGE OF ENVIRONMENTS WITHIN THE NWTT STUDY AREA Approximate TTS ranges (meters) 1 Hearing group Sonar bin LF4 1 second High-frequency cetaceans ............................................................................... VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00061 Fmt 4701 Sfmt 4702 30 seconds 0 (0–0) E:\FR\FM\02JNP2.SGM 0 (0–0) 02JNP2 60 seconds 0 (0–0) 120 seconds 1 (0–1) 33974 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 20—RANGES TO TEMPORARY THRESHOLD SHIFT (METERS) FOR SONAR BIN LF4 OVER A REPRESENTATIVE RANGE OF ENVIRONMENTS WITHIN THE NWTT STUDY AREA—Continued Approximate TTS ranges (meters) 1 Hearing group Sonar bin LF4 1 second Low-frequency cetaceans ................................................................................ Mid-frequency cetaceans ................................................................................. Otariids ............................................................................................................. Phocids ............................................................................................................ 30 seconds 22 (19–30) 0 (0–0) 0 (0–0) 2 (1–3) 60 seconds 32 (25–230) 0 (0–0) 0 (0–0) 4 (3–4) 120 seconds 41 (30–230) 0 (0–0) 0 (0–0) 4 (4–5) 61 (45–100) 0 (0–0) 0 (0–0) 7 (6–9) 1 Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in parentheses. Notes: HF = high-frequency, TTS = temporary threshold shift. TABLE 21—RANGES TO TEMPORARY THRESHOLD SHIFT (METERS) FOR SONAR BIN MF1 OVER A REPRESENTATIVE RANGE OF ENVIRONMENTS WITHIN THE NWTT STUDY AREA Approximate TTS ranges (meters) 1 Hearing group Sonar bin MF1 1 second High-frequency cetaceans ............................................................................... 2,466 (80– 6,275) 1,054 (80– 2,775) 225 (80–380) 67 (60–110) 768 (80– 2,025) Low-frequency cetaceans ................................................................................ Mid-frequency cetaceans ................................................................................. Otariids ............................................................................................................. Phocids ............................................................................................................ 30 seconds 60 seconds 120 seconds 2,466 (80– 6,275) 1,054 (80– 2,775) 225 (80–380) 67 (60–110) 768 (80– 2,025) 3,140 (80– 10,275) 1,480 (80– 4,525) 331 (80–525) 111 (80–170) 1,145 (80– 3,275) 3,740 (80– 13,525) 1,888 (80– 5,275) 411 (80–700) 143 (80–250) 1,388 (80– 3,775) 1 Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in parentheses. Ranges for 1 second and 30 second periods are identical for Bin MF1 because this system nominally pings every 50 seconds; therefore, these periods encompass only a single ping. Notes: MF = mid-frequency, TTS = temporary threshold shift. TABLE 22—RANGES TO TEMPORARY THRESHOLD SHIFT (METERS) FOR SONAR BIN MF4 OVER A REPRESENTATIVE RANGE OF ENVIRONMENTS WITHIN THE NWTT STUDY AREA Approximate TTS ranges (meters) 1 Hearing group Sonar bin MF4 1 second 30 seconds 60 seconds High-frequency cetaceans ............................................................. 279 (220–600) Low-frequency cetaceans .............................................................. Mid-frequency cetaceans ............................................................... Otariids ........................................................................................... Phocids .......................................................................................... 87 (85–110) 22 (22–25) 8 (8–8) 66 (65–80) 647 (420– 1,275) 176 (130–320) 35 (35–45) 15 (15–17) 116 (110–200) 878 (500– 1,525) 265 (190–575) 50 (45–55) 19 (19–23) 173 (150–300) 120 seconds 1,205 (525–2,275) 477 (290–975) 71 (70–85) 25 (25–30) 303 (240–675) 1 Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in parentheses. Notes: MF = mid-frequency, TTS = temporary threshold shift. khammond on DSKJM1Z7X2PROD with PROPOSALS2 TABLE 23—RANGES TO TEMPORARY THRESHOLD SHIFT (METERS) FOR SONAR BIN MF5 OVER A REPRESENTATIVE RANGE OF ENVIRONMENTS WITHIN THE NWTT STUDY AREA Approximate TTS ranges (meters) 1 Hearing group Sonar bin MF5 High-frequency cetaceans ............................................................................... Low-frequency cetaceans ................................................................................ Mid-frequency cetaceans ................................................................................. Otariids ............................................................................................................. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00062 Fmt 4701 1 second 30 seconds 60 seconds 120 seconds 115 (110–180) 11 (10–13) 6 (0–9) 0 (0–0) 115 (110–180) 11 (10–13) 6 (0–9) 0 (0–0) 174 (150–390) 17 (16–19) 12 (11–14) 0 (0–0) 292 (210–825) 24 (23–25) 18 (17–22) 0 (0–0) Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 33975 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 23—RANGES TO TEMPORARY THRESHOLD SHIFT (METERS) FOR SONAR BIN MF5 OVER A REPRESENTATIVE RANGE OF ENVIRONMENTS WITHIN THE NWTT STUDY AREA—Continued Approximate TTS ranges (meters) 1 Hearing group Sonar bin MF5 1 second Phocids ............................................................................................................ 30 seconds 9 (8–11) 9 (8–11) 60 seconds 15 (14–17) 120 seconds 22 (21–25) 1 Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in parentheses. Notes: MF = mid-frequency, TTS = temporary threshold shift. TABLE 24—RANGES TO TEMPORARY THRESHOLD SHIFT (METERS) FOR SONAR BIN HF4 OVER A REPRESENTATIVE RANGE OF ENVIRONMENTS WITHIN THE NWTT STUDY AREA Approximate TTS Ranges (meters) 1 Hearing group Sonar bin HF4 1 second 30 seconds High-frequency cetaceans ............................................................................... 236 (60–675) 387 (60–875) Low-frequency cetaceans ................................................................................ Mid-frequency cetaceans ................................................................................. Otariids ............................................................................................................. Phocids ............................................................................................................ 2 (0–3) 12 (7–20) 0 (0–0) 3 (0–5) 3 (1–6) 21 (12–40) 0 (0–0) 6 (4–10) 60 seconds 503 (60– 1,025) 5 (3–8) 29 (17–60) 0 (0–0) 9 (5–15) 120 seconds 637 (60– 1,275) 8 (5–12) 43 (24–90) 1 (0–1) 14 (8–25) 1 Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in parentheses. Notes: HF = high-frequency, TTS = temporary threshold shift. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Explosives The following section provides the range (distance) over which specific physiological or behavioral effects are expected to occur based on the explosive criteria (see Chapter 6, Section 6.5.2 (Impacts from Explosives) of the Navy’s rulemaking/LOA application and the ‘‘Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III)’’ report (U.S. Department of the Navy, 2017c)) and the explosive propagation calculations from the Navy Acoustic Effects Model (see Chapter 6, Section 6.5.2.2 (Impact Ranges for Explosives) of the Navy’s rulemaking/LOA application). The range to effects are shown for a range of explosive bins, from E1 (up to 0.25 lb net explosive weight) to E11 (greater than 500 lb to 650 lb net explosive weight) (Tables 25 through 31). Ranges are determined by modeling the distance that noise from an explosion would need to propagate to reach exposure level thresholds specific to a hearing group that would cause behavioral response (to the degree of Level B behavioral harassment), TTS, PTS, and non-auditory injury. NMFS has reviewed the range distance to effect data provided by the Navy and concurs with the analysis. Range to effects is important information in not only predicting impacts from explosives, but also in verifying the accuracy of model results against real-world situations and determining adequate mitigation ranges to avoid higher level effects, especially physiological effects to marine mammals. For additional information on how ranges to impacts from explosions were estimated, see the technical report ‘‘Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and Analytical Approach for Phase III Training and Testing’’ (U.S. Navy, 2018). Tables 25 through 29 show the minimum, average, and maximum ranges to onset of auditory and likely behavioral effects that rise to the level of Level B harassment for highfrequency cetaceans based on the developed thresholds. Ranges are provided for a representative source depth and cluster size (the number of rounds fired, or buoys dropped, within a very short duration) for each bin. For events with multiple explosions, sound from successive explosions can be expected to accumulate and increase the range to the onset of an impact based on SEL thresholds. Ranges to non-auditory injury and mortality are shown in Tables 30 and 31, respectively. Table 25 shows the minimum, average, and maximum ranges to onset of auditory and likely behavioral effects that rise to the level of Level B harassment for high-frequency cetaceans based on the developed thresholds. TABLE 25—SEL-BASED RANGES TO ONSET PTS, ONSET TTS, AND BEHAVIORAL REACTION (IN METERS) FOR HIGHFREQUENCY CETACEANS Range to effects for explosives: High-frequency cetaceans 1 Bin Source depth (m) E1 ......................................... 0.1 E2 ......................................... 0.1 VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Cluster size PO 00000 Range to PTS (m) 1 18 1 Frm 00063 361 (350–370) 1,002 (925–1,025) 439 (420–450) Fmt 4701 Sfmt 4702 Range to TTS (m) 1,108 (1,000–1,275) 2,404 (1,275–4,025) 1,280 (1,025–1,775) E:\FR\FM\02JNP2.SGM 02JNP2 Range to behavioral (m) 1,515 (1,025–2,025) 3,053 (1,275–5,025) 1,729 (1,025–2,525) 33976 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 25—SEL-BASED RANGES TO ONSET PTS, ONSET TTS, AND BEHAVIORAL REACTION (IN METERS) FOR HIGHFREQUENCY CETACEANS—Continued Range to effects for explosives: High-frequency cetaceans 1 Bin Source depth (m) E3 ......................................... Cluster size 5 1 12 1 12 2 2 2 2 1 20 1 1 1 1 1 1 10 18.25 E4 ......................................... 10 30 70 90 0.1 E5 ......................................... E7 ......................................... E8 ......................................... E10 ....................................... E11 ....................................... 10 30 45.75 0.1 91.4 200 Range to PTS (m) 826 (775–875) 1,647 (160–3,525) 3,140 (160–9,525) 684 (550–1,000) 1,774 (1,025–3,775) 1,390 (950–3,025) 1,437 (925–2,775) 1,304 (925–2,275) 1,534 (900–2,525) 940 (850–1,025) 1,930 (1,275–2,775) 2,536 (1,275–3,775) 1,916 (1,025–4,275) 1,938 (1,275–4,025) 1,829 (1,025–2,775) 3,245 (2,025–6,775) 3,745 (3,025–5,025) Range to TTS (m) 1,953 (1,275–3,025) 2,942 (160–10,275) 3,804 (160–17,525) 2,583 (1,025–5,025) 5,643 (1,775–10,025) 5,250 (2,275–8,275) 4,481 (1,525–7,775) 3,845 (2,525–7,775) 5,115 (2,525–7,525) 2,159 (1,275–3,275) 4,281 (1,775–6,525) 6,817 (2,775–11,025) 5,784 (2,775–10,525) 4,919 (1,775–11,275) 4,166 (1,775–6,025) 6,459 (2,525–15,275) 7,116 (4,275–11,275) Range to behavioral (m) 2,560 (1,275–4,275) 3,232 (160–12,275) 3,944 (160–21,775) 4,217 (1,525–7,525) 7,220 (2,025–13,275) 7,004 (2,775–11,275) 5,872 (2,775–10,525) 5,272 (3,525–9,525) 6,840 (3,275–10,275) 2,762 (1,275–4,275) 5,176 (2,025–7,775) 8,963 (3,525–14,275) 7,346 (2,775–12,025) 5,965 (2,025–15,525) 5,023 (2,025–7,525) 7,632 (2,775–19,025) 8,727 (5,025–15,025) 1 Average distance (meters) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum distances (due to varying propagation environments), which are in parentheses. Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift. Table 26 shows the minimum, average, and maximum ranges to onset of auditory and likely behavioral effects that rise to the level of Level B harassment for low-frequency cetaceans based on the developed thresholds. TABLE 26—SEL-BASED RANGES TO ONSET PTS, ONSET TTS, AND BEHAVIORAL REACTION (IN METERS) FOR LOWFREQUENCY CETACEANS Range to effects for explosives: Low-frequency cetaceans 1 Bin Source depth (meters) E1 ......................................... 0.1 E2 ......................................... 0.1 E3 ......................................... 10 Cluster size 1 18 1 5 1 12 1 12 2 2 2 2 1 20 1 1 1 1 1 1 18.25 E4 ......................................... 10 30 70 90 0.1 E5 ......................................... E7 ......................................... E8 ......................................... E10 ....................................... E11 ....................................... 10 30 45.75 0.1 91.4 200 Range to PTS (meters) 52 (50–55) 177 (110–200) 66 (55–70) 128 (90–140) 330 (160–550) 1,177 (160–2,775) 198 (180–220) 646 (390–1,025) 462 (400–600) 527 (330–950) 490 (380–775) 401 (360–500) 174 (100–260) 550 (200–700) 1,375 (875–2,525) 1,334 (675–2,025) 1,227 (575–2,525) 546 (200–700) 2,537 (950–5,525) 2,541 (1,525–4,775) Range to TTS (meters) 221 (120–250) 656 (230–875) 276 (140–320) 512 (200–650) 1,583 (160–4,025) 2,546 (160–11,775) 1,019 (490–2,275) 3,723 (800–9,025) 3,743 (2,025–7,025) 3,253 (1,775–4,775) 3,026 (1,525–4,775) 3,041 (1,275–4,525) 633 (220–850) 1,352 (420–2,275) 7,724 (3,025–15,025) 7,258 (2,775–11,025) 3,921 (1,025–17,275) 1,522 (440–5,275) 11,249 (1,775–50,775) 7,407 (2,275–43,275) Range to behavioral (meters) 354 (160–420) 836 (280–1,025) 432 (180–525) 735 (250–975) 2,085 (160–7,525) 2,954 (160–17,025) 1,715 (625–4,025) 6,399 (1,025–46,525) 6,292 (2,525–13,275) 5,540 (2,275–8,275) 5,274 (2,275–7,775) 5,399 (1,775–9,275) 865 (270–1,275) 2,036 (700–4,275) 11,787 (4,525–25,275) 11,644 (4,525–24,275) 7,961 (1,275–48,525) 3,234 (850–30,525) 37,926 (6,025–94,775) 42,916 (6,275–51,275) khammond on DSKJM1Z7X2PROD with PROPOSALS2 1 Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses. Values depict the range produced by SEL hearing threshold criteria levels. Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift. Table 27 shows the minimum, average, and maximum ranges to onset VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 of auditory and likely behavioral effects that rise to the level of Level B PO 00000 Frm 00064 Fmt 4701 Sfmt 4702 harassment for mid-frequency cetaceans based on the developed thresholds. E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 33977 TABLE 27—SEL-BASED RANGES TO ONSET PTS, ONSET TTS, AND BEHAVIORAL REACTION (IN METERS) FOR MIDFREQUENCY CETACEANS Range to effects for explosives: Mid-frequency cetaceans 1 Source depth (meters) Bin E1 ....................................................................... 0.1 E2 ....................................................................... 0.1 E3 ....................................................................... 10 10 30 45.75 0.1 91.4 1 18 1 5 1 12 1 12 2 2 2 2 1 20 1 1 1 1 1 25 (25–25) 96 (90–100) 30 (30–30) 64 (60–65) 61 (50–100) 300 (160–625) 40 (35–40) 127 (120–130) 73 (70–75) 71 (65–90) 63 (60–85) 59 (55–85) 79 (75–80) 295 (280–300) 121 (110–130) 111 (100–130) 133 (120–170) 273 (260–280) 242 (220–310) 200 1 209 (200–300) 18.25 E4 ....................................................................... 10 30 70 90 0.1 E5 ....................................................................... E7 ....................................................................... E8 ....................................................................... E10 ..................................................................... E11 ..................................................................... Range to PTS (meters) Cluster size Range to TTS (meters) Range to behavioral (meters) 118 (110–120) 430 (410–440) 146 (140–150) 298 (290–300) 512 (160–750) 1,604 (160–3,525) 199 (180–280) 709 (575–1,000) 445 (400–575) 554 (320–1,025) 382 (320–675) 411 (310–900) 360 (350–370) 979 (800–1,275) 742 (575–1,275) 826 (500–1,775) 817 (575–1,525) 956 (775–1,025) 1,547 (1,025– 3,025) 1,424 (1,025– 2,025) 203 (190–210) 676 (600–700) 246 (230–250) 493 (470–500) 928 (160–2,025) 2,085 (160–5,525) 368 (310–800) 1,122 (875–2,525) 765 (600–1,275) 850 (525–1,775) 815 (525–1,275) 870 (525–1,275) 575 (525–600) 1,442 (925–1,775) 1,272 (875–2,275) 1,327 (925–2,275) 1,298 (925–2,525) 1,370 (900–1,775) 2,387 (1,275– 4,025) 2,354 (1,525– 3,775) 1 Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses. Note: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift. Table 28 shows the minimum, average, and maximum ranges to onset of auditory and likely behavioral effects that rise to the level of Level B harassment for otariid pinnipeds based on the developed thresholds. TABLE 28—SEL-BASED RANGES TO ONSET PTS, ONSET TTS, AND BEHAVIORAL REACTION (IN METERS) FOR OTARIIDS Range to effects for explosives: Otariids 1 Source depth (meters) Bin Cluster size E1 ....................................................................... 0.1 E2 ....................................................................... 0.1 E3 ....................................................................... 10 18.25 E4 ....................................................................... 10 30 70 90 0.1 E5 ....................................................................... E7 ....................................................................... 10 30 45.75 0.1 91.4 200 khammond on DSKJM1Z7X2PROD with PROPOSALS2 E8 ....................................................................... E10 ..................................................................... E11 ..................................................................... 1 18 1 5 1 12 1 12 2 2 2 2 1 20 1 1 1 1 1 1 Range to PTS (meters) 7 (7–8) 25 (25–25) 9 (9–10) 19 (19–20) 21 (18–25) 82 (75–100) 15 (15–15) 53 (50–55) 30 (30–30) 25 (25–25) 26 (25–35) 26 (25–35) 25 (24–25) 93 (90–95) 60 (60–60) 53 (50–65) 55 (55–55) 87 (85–90) 100 (100–100) 94 (90–100) Range to TTS (meters) 34 (30–35) 124 (120–130) 43 (40–45) 88 (85–90) 135 (120–210) 551 (160–875) 91 (85–95) 293 (260–430) 175 (170–180) 176 (160–250) 148 (140–200) 139 (130–190) 111 (110–120) 421 (390–440) 318 (300–360) 376 (290–700) 387 (310–750) 397 (370–410) 775 (550–1,275) 554 (525–700) Range to behavioral (meters) 58 (55–60) 208 (200–210) 72 (70–75) 145 (140–150) 250 (160–370) 954 (160–2,025) 155 (150–160) 528 (420–825) 312 (300–350) 400 (290–750) 291 (250–400) 271 (250–360) 188 (180–190) 629 (550–725) 575 (500–775) 742 (500–1,025) 763 (525–1,275) 599 (525–675) 1,531 (900–3,025) 1,146 (900–1,525) 1 Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses. Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift. Table 29 shows the minimum, average, and maximum ranges to onset VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 of auditory and likely behavioral effects that rise to the level of Level B PO 00000 Frm 00065 Fmt 4701 Sfmt 4702 harassment for phocid pinnipeds based on the developed thresholds. E:\FR\FM\02JNP2.SGM 02JNP2 33978 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 29—SEL-BASED RANGES TO ONSET PTS, ONSET TTS, AND BEHAVIORAL REACTION (IN METERS) FOR PHOCIDS Range to effects for explosives: Phocids 1 Source depth (meters) Bin E1 ......................................... 0.1 E2 ......................................... 0.1 E3 ......................................... 10 1 18 1 5 1 12 1 12 2 2 2 2 1 20 1 1 1 1 1 1 18.25 E4 ......................................... 10 30 70 90 0.1 E5 ......................................... E7 ......................................... E8 ......................................... E10 ....................................... E11 ....................................... Range to PTS (meters) Cluster size 10 30 45.75 0.1 91.4 200 Range to TTS (meters) 47 (45–50) 171 (160–180) 59 (55–60) 118 (110–120) 185 (160–260) 760 (160–1,525) 112 (110–120) 389 (330–625) 226 (220–240) 276 (200–600) 201 (180–280) 188 (170–270) 151 (140–160) 563 (550–575) 405 (370–490) 517 (370–875) 523 (390–1,025) 522 (500–525) 1,063 (675–2,275) 734 (675–850) Range to behavioral (meters) 219 (210–230) 764 (725–800) 273 (260–280) 547 (525–550) 1,144 (160–2,775) 2,262 (160–8,025) 628 (500–950) 2,248 (1,275–4,275) 1,622 (950–3,275) 1,451 (1,025–2,275) 1,331 (1,025–1,775) 1,389 (975–2,025) 685 (650–700) 1,838 (1,275–2,275) 3,185 (1,775–6,025) 2,740 (1,775–4,275) 2,502 (1,525–6,025) 1,800 (1,275–2,275) 5,043 (2,775–10,525) 5,266 (3,525–9,025) 366 (350–370) 1,088 (1,025–1,275) 454 (440–460) 881 (825–925) 1,655 (160–4,525) 2,708 (160–12,025) 1,138 (875–2,525) 4,630 (1,275–8,525) 3,087 (1,775–5,775) 2,611 (1,775–4,275) 2,403 (1,525–3,525) 2,617 (1,775–3,775) 1,002 (950–1,025) 2,588 (1,525–3,525) 5,314 (2,275–11,025) 4,685 (3,025–7,275) 3,879 (2,025–10,275) 2,470 (1,525–3,275) 7,371 (3,275–18,025) 7,344 (5,025–12,775) 1 Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses. Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift. Table 30 shows the minimum, average, and maximum ranges due to varying propagation conditions to nonauditory injury as a function of animal mass and explosive bin (i.e., net explosive weight). Ranges to gastrointestinal tract injury typically exceed ranges to slight lung injury; therefore, the maximum range to effect is not mass-dependent. Animals within these water volumes would be expected to receive minor injuries at the outer ranges, increasing to more substantial injuries, and finally mortality as an animal approaches the detonation point. TABLE 30—RANGES 1 TO NON-AUDITORY INJURY (IN METERS) FOR ALL MARINE MAMMAL HEARING GROUPS TABLE 30—RANGES 1 TO NON-AUDITORY INJURY (IN METERS) FOR ALL MARINE MAMMAL HEARING GROUPS—Continued Range to non-auditory injury (meters) 1 Bin E1 ......................................... E2 ......................................... E3 ......................................... E4 ......................................... E5 ......................................... E7 ......................................... E8 ......................................... E10 ....................................... 12 (11–13) 16 (15–16) 25 (25–45) 31 (23–50) 40 (40–40) 104 (80–190) 149 (130–210) 153 (100–400) Bin Range to non-auditory injury (meters) 1 E11 ....................................... 419 (350–725) 1 Distances in meters (m). Average distance is shown with the minimum and maximum distances due to varying propagation environments in parentheses. Modeled ranges based on peak pressure for a single explosion generally exceed the modeled ranges based on impulse (related to animal mass and depth). Ranges to mortality, based on animal mass, are shown in Table 31 below. TABLE 31—RANGES 1 TO MORTALITY (IN METERS) FOR ALL MARINE MAMMAL HEARING GROUPS AS A FUNCTION OF ANIMAL MASS Range to mortality (meters) for various animal mass intervals (kg) 1 Bin khammond on DSKJM1Z7X2PROD with PROPOSALS2 10 kg E1 ............................................................. E2 ............................................................. E3 ............................................................. E4 ............................................................. E5 ............................................................. E7 ............................................................. E8 ............................................................. E10 ........................................................... E11 ........................................................... 3 (2–3) 4 (3–5) 10 (9–20) 13 (11–19) 13 (11–15) 49 (40–80) 65 (60–75) 43 (40–50) 185 (90–230) 250 kg 1,000 kg 1 (0–3) 2 (1–3) 5 (3–20) 7 (4–13) 7 (4–11) 27 (15–60) 34 (22–55) 25 (16–40) 90 (30–170) 13 17 13 40 0 (0–0) 1 (0–1) 2 (1–5) 3 (2–4) 3 (3–4) (10–20) (14–20) (11–16) (30–50) 5,000 kg 0 (0–0) 0 (0–0) 0 (0–3) 2 (1–3) 2 (1–3) 9 (5–12) 11 (9–13) 9 (7–11) 28 (23–30) 25,000 kg 0 (0–0) 0 (0–0) 0 (0–1) 1 (1–1) 1 (1–1) 4 (4–6) 6 (5–6) 5 (4–6) 15 (13–16) 72,000 kg 0 (0–0) 0 (0–0) 0 (0–1) 1 (0–1) 1 (0–1) 3 (2–4) 5 (4–5) 4 (3–4) 11 (9–13) 1 Average distance to mortality (meters) is depicted above the minimum and maximum distances, which are in parentheses for each animal mass interval. Notes: kg = kilogram. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00066 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 Marine Mammal Density A quantitative analysis of impacts on a species or stock requires data on their abundance and distribution that may be affected by anthropogenic activities in the potentially impacted area. The most appropriate metric for this type of analysis is density, which is the number of animals present per unit area. Marine species density estimation requires a significant amount of effort to both collect and analyze data to produce a reasonable estimate. Unlike surveys for terrestrial wildlife, many marine species spend much of their time submerged, and are not easily observed. In order to collect enough sighting data to make reasonable density estimates, multiple observations are required, often in areas that are not easily accessible (e.g., far offshore). Ideally, marine mammal species sighting data would be collected for the specific area and time period (e.g., season) of interest and density estimates derived accordingly. However, in many places, poor weather conditions and high sea states prohibit the completion of comprehensive visual surveys. For most cetacean species, abundance is estimated using line-transect surveys or mark-recapture studies (e.g., Barlow, 2010; Barlow and Forney, 2007; Calambokidis et al., 2008). The result provides one single density estimate value for each species across broad geographic areas. This is the general approach applied in estimating cetacean abundance in NMFS’ Stock Assessment Reports (SARs). Although the single value provides a good average estimate of abundance (total number of individuals) for a specified area, it does not provide information on the species distribution or concentrations within that area, and it does not estimate density for other timeframes or seasons that were not surveyed. More recently, spatial habitat modeling developed by NMFS’ Southwest Fisheries Science Center has been used to estimate cetacean densities (Barlow et al., 2009; Becker et al., 2010, 2012a, b, c, 2014, 2016; Ferguson et al., 2006a; Forney et al., 2012, 2015; Redfern et al., 2006). These models estimate cetacean density as a continuous function of habitat variables (e.g., sea surface temperature, seafloor depth, etc.) and thus allow predictions of cetacean densities on finer spatial scales than traditional linetransect or mark recapture analyses and for areas that have not been surveyed. Within the geographic area that was modeled, densities can be predicted wherever these habitat variables can be measured or estimated. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Ideally, density data would be available for all species throughout the study area year-round, in order to best estimate the impacts of Navy activities on marine species. However, in many places, ship availability, lack of funding, inclement weather conditions, and high sea states prevent the completion of comprehensive year-round surveys. Even with surveys that are completed, poor conditions may result in lower sighting rates for species that would typically be sighted with greater frequency under favorable conditions. Lower sighting rates preclude having an acceptably low uncertainty in the density estimates. A high level of uncertainty, indicating a low level of confidence in the density estimate, is typical for species that are rare or difficult to sight. In areas where survey data are limited or non-existent, known or inferred associations between marine habitat features and the likely presence of specific species are sometimes used to predict densities in the absence of actual animal sightings. Consequently, there is no single source of density data for every area, species, and season because of the fiscal costs, resources, and effort involved in providing enough survey coverage to sufficiently estimate density. To characterize marine species density for large oceanic regions, the Navy reviews, critically assesses, and prioritizes existing density estimates from multiple sources, requiring the development of a systematic method for selecting the most appropriate density estimate for each combination of species/stock, area, and season. The selection and compilation of the best available marine species density data resulted in the Navy Marine Species Density Database (NMSDD), which includes seasonal density values for every marine mammal species and stock present within the NWTT Study Area. This database is described in the technical report titled ‘‘U.S. Navy Marine Species Density Database Phase III for the Northwest Training and Testing Study Area’’ (U.S. Department of the Navy, 2019), hereafter referred to as the Density Technical Report. NMFS vetted all cetacean densities by the Navy prior to use in the Navy’s acoustic analysis for the current NWTT rulemaking process. A variety of density data and density models are needed in order to develop a density database that encompasses the entirety of the NWTT Study Area. Because this data is collected using different methods with varying amounts of accuracy and uncertainty, the Navy has developed a hierarchy to ensure the most accurate data is used when PO 00000 Frm 00067 Fmt 4701 Sfmt 4702 33979 available. The Density Technical Report describes these models in detail and provides detailed explanations of the models applied to each species density estimate. The below list describes models in order of preference. 1. Spatial density models are preferred and used when available because they provide an estimate with the least amount of uncertainty by deriving estimates for divided segments of the sampling area. These models (see Becker et al., 2016; Forney et al., 2015) predict spatial variability of animal presence as a function of habitat variables (e.g., sea surface temperature, seafloor depth, etc.). This model is developed for areas, species, and, when available, specific timeframes (months or seasons) with sufficient survey data; therefore, this model cannot be used for species with low numbers of sightings. 2. Stratified design-based density estimates use line-transect survey data with the sampling area divided (stratified) into sub-regions, and a density is predicted for each sub-region (see Barlow, 2016; Becker et al., 2016; Bradford et al., 2017; Campbell et al., 2014; Jefferson et al., 2014). While geographically stratified density estimates provide a better indication of a species’ distribution within the study area, the uncertainty is typically high because each sub-region estimate is based on a smaller stratified segment of the overall survey effort. 3. Design-based density estimations use line-transect survey data from land and aerial surveys designed to cover a specific geographic area (see Carretta et al., 2015). These estimates use the same survey data as stratified design-based estimates, but are not segmented into sub-regions and instead provide one estimate for a large surveyed area. Although relative environmental suitability (RES) models provide estimates for areas of the oceans that have not been surveyed using information on species occurrence and inferred habitat associations and have been used in past density databases, these models were not used in the current quantitative analysis. The Navy describes some of the challenges of interpreting the results of the quantitative analysis summarized above and described in the Density Technical Report: ‘‘It is important to consider that even the best estimate of marine species density is really a model representation of the values of concentration where these animals might occur. Each model is limited to the variables and assumptions considered by the original data source provider. No mathematical model representation of any biological E:\FR\FM\02JNP2.SGM 02JNP2 33980 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules population is perfect, and with regards to marine mammal biodiversity, any single model method will not completely explain the actual distribution and abundance of marine mammal species. It is expected that there would be anomalies in the results that need to be evaluated, with independent information for each case, to support if we might accept or reject a model or portions of the model (U.S. Department of the Navy, 2017a).’’ The Navy’s estimate of abundance (based on density estimates used in the NWTT Study Area) utilizes NMFS’ SARs, except for species with high site fidelity/smaller home ranges within the NWTT Study Area, relative to their geographic distribution (e.g., harbor seals). For harbor seals in the inland waters, more up-to-date, site specific population estimates were available. For some species, the stock assessment for a given species may exceed the Navy’s density prediction because those species’ home range extends beyond the Study Area boundaries. For other species, the stock assessment abundance may be much less than the number of animals in the Navy’s modeling given that the NWTT Study Area extends beyond the U.S waters covered by the SAR abundance estimate. The primary source of density estimates are geographically specific survey data and either peer-reviewed line-transect estimates or habitat-based density models that have been extensively validated to provide the most accurate estimates possible. NMFS coordinated with the Navy in the development of its take estimates and concurs that the Navy’s approach for density appropriately utilizes the best available science. Later, in the Preliminary Analysis and Negligible Impact Determination section, we assess how the estimated take numbers compare to stock abundance in order to better understand the potential number of individuals impacted, and the rationale for which abundance estimate is used is included there. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Take Request The 2019 NWTT DSEIS/OEIS considered all training and testing activities proposed to occur in the NWTT Study Area that have the potential to result in the MMPA defined take of marine mammals. The Navy determined that the three stressors below could result in the incidental taking of marine mammals. NMFS has reviewed the Navy’s data and analysis and determined that it is complete and accurate and agrees that the following stressors have the potential to result in VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 takes by harassment of marine mammals from the Navy’s planned activities. • Acoustics (sonar and other transducers); • Explosives (explosive shock wave and sound, assumed to encompass the risk due to fragmentation); and • Vessel strike Acoustic and explosive sources have the potential to result in incidental takes of marine mammals by harassment and injury. Vessel strikes have the potential to result in incidental take from injury, serious injury, and/or mortality. The quantitative analysis process used for the 2019 NWTT DSEIS/OEIS and the Navy’s take request in the rulemaking/LOA application to estimate potential exposures to marine mammals resulting from acoustic and explosive stressors is detailed in the technical report titled Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and Analytical Approach for Phase III Training and Testing (U.S. Department of the Navy, 2018). The Navy Acoustic Effects Model estimates acoustic and explosive effects without taking mitigation into account; therefore, the model overestimates predicted impacts on marine mammals within mitigation zones. To account for mitigation for marine species in the take estimates, the Navy conducts a quantitative assessment of mitigation. The Navy conservatively quantifies the manner in which procedural mitigation is expected to reduce the risk for modelestimated PTS for exposures to sonars and for model-estimated mortality for exposures to explosives, based on species sightability, observation area, visibility, and the ability to exercise positive control over the sound source. Where the analysis indicates mitigation would effectively reduce risk, the model-estimated PTS are considered reduced to TTS and the modelestimated mortalities are considered reduced to injury. For a complete explanation of the process for assessing the effects of mitigation, see the Navy’s rulemaking/LOA application and the technical report titled Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and Analytical Approach for Phase III Training and Testing (U.S. Department of the Navy, 2018). The extent to which the mitigation areas reduce impacts on the affected species is addressed separately in the Preliminary Analysis and Negligible Impact Determination section. The Navy assessed the effectiveness of its procedural mitigation measures on a per-scenario basis for four factors: (1) Species sightability, (2) a Lookout’s ability to observe the range to PTS (for PO 00000 Frm 00068 Fmt 4701 Sfmt 4702 sonar and other transducers) and range to mortality (for explosives), (3) the portion of time when mitigation could potentially be conducted during periods of reduced daytime visibility (to include inclement weather and high sea-state) and the portion of time when mitigation could potentially be conducted at night, and (4) the ability for sound sources to be positively controlled (e.g., powered down). During training and testing activities, there is typically at least one, if not numerous, support personnel involved in the activity (e.g., range support personnel aboard a torpedo retrieval boat or support aircraft). In addition to the Lookout posted for the purpose of mitigation, these additional personnel observe and disseminate marine species sighting information amongst the units participating in the activity whenever possible as they conduct their primary mission responsibilities. However, as a conservative approach to assigning mitigation effectiveness factors, the Navy elected to only account for the minimum number of required Lookouts used for each activity; therefore, the mitigation effectiveness factors may underestimate the likelihood that some marine mammals may be detected during activities that are supported by additional personnel who may also be observing the mitigation zone. The Navy used the equations in the below sections to calculate the reduction in model-estimated mortality impacts due to implementing procedural mitigation. Equation 1: Mitigation Effectiveness = Species Sightability × Visibility × Observation Area × Positive Control Species Sightability is the ability to detect marine mammals and is dependent on the animal’s presence at the surface and the characteristics of the animal that influence its sightability. The Navy considered applicable data from the best available science to numerically approximate the sightability of marine mammals and determined the standard ‘‘detection probability’’ referred to as g(0) is most appropriate. Also, Visibility = 1¥sum of individual visibility reduction factors; Observation Area = portion of impact range that can be continuously observed during an event; and Positive Control = positive control factor of all sound sources involving mitigation. For further details on these mitigation effectiveness factors please refer to the technical report titled Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and Analytical Approach for Phase III Training and E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Testing (U.S. Department of the Navy, 2018). To quantify the number of marine mammals predicted to be sighted by Lookouts in the injury zone during implementation of procedural mitigation for sonar and other transducers, the species sightability is multiplied by the mitigation effectiveness scores and number of model-estimated PTS impacts, as shown in the equation below: Equation 2: Number of Animals Sighted by Lookouts = Mitigation Effectiveness × ModelEstimated Impacts The marine mammals sighted by Lookouts in the injury zone during implementation of mitigation, as calculated by the equation above, would avoid being exposed to these higher level impacts. To quantify the number of marine mammals predicted to be sighted by Lookouts in the mortality zone during implementation of procedural mitigation during events using explosives, the species sightability is multiplied by the mitigation effectiveness scores and number of model-estimated mortality impacts, as shown in equation 1 above. The marine mammals predicted to be sighted in the mortality zone by Lookouts during implementation of procedural mitigation, as calculated by the above equation 2, are predicted to avoid exposure in these ranges. The Navy corrects the category of predicted impact for the number of animals sighted within the mitigation zone, but does not modify the total number of animals predicted to experience impacts from the scenario. For example, the number of animals sighted (i.e., number of animals that will avoid mortality) is first subtracted from the modelpredicted mortality impacts, and then added to the model-predicted injurious impacts. The NAEMO (animal movement) model overestimates the number of marine mammals that would be exposed to sound sources that could cause PTS because the model does not consider horizontal movement of animats, including avoidance of high intensity sound exposures. Therefore, the potential for animal avoidance is considered separately. At close ranges and high sound levels, avoidance of the area immediately around the sound source is one of the assumed behavioral responses for marine mammals. Animal avoidance refers to the movement out of the immediate injury zone for subsequent exposures, not wide-scale area avoidance. Various researchers have demonstrated that cetaceans can VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 perceive the location and movement of a sound source (e.g., vessel, seismic source, etc.) relative to their own location and react with responsive movement away from the source, often at distances of 1 km or more (Au & Perryman,1982; Jansen et al., 2010; Richardson et al., 1995; Tyack et al., 2011; Watkins, 1986; Wu¨rsig et al., 1998) A marine mammal’s ability to avoid a sound source and reduce its cumulative sound energy exposure would reduce risk of both PTS and TTS. However, the quantitative analysis conservatively only considers the potential to reduce some instances of PTS by accounting for marine mammals swimming away to avoid repeated highlevel sound exposures. All reductions in PTS impacts from likely avoidance behaviors are instead considered TTS impacts. NMFS coordinated with the Navy in the development of this quantitative method to address the effects of procedural mitigation on acoustic and explosive exposures and takes, and NMFS independently reviewed and concurs with the Navy that it is appropriate to incorporate the quantitative assessment of mitigation into the take estimates based on the best available science. For additional information on the quantitative analysis process and mitigation measures, refer to the technical report titled Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and Analytical Approach for Phase III Training and Testing (U.S. Department of the Navy, 2018) and Chapter 6 (Take Estimates for Marine Mammals) and Chapter 11 (Mitigation Measures) of the Navy’s rulemaking/LOA application. As a general matter, NMFS does not prescribe the methods for estimating take for any applicant, but we review and ensure that applicants use the best available science, and methodologies that are logical and technically sound. Applicants may use different methods of calculating take (especially when using models) and still get to a result that is representative of the best available science and that allows for a rigorous and accurate evaluation of the effects on the affected populations. There are multiple pieces of the Navy take estimation methods—propagation models, animat movement models, and behavioral thresholds, for example. NMFS evaluates the acceptability of these pieces as they evolve and are used in different rules and impact analyses. Some of the pieces of the Navy’s take estimation process have been used in Navy incidental take rules since 2009 and undergone multiple public comment processes; all of them have PO 00000 Frm 00069 Fmt 4701 Sfmt 4702 33981 undergone extensive internal Navy review, and all of them have undergone comprehensive review by NMFS, which has sometimes resulted in modifications to methods or models. The Navy uses rigorous review processes (verification, validation, and accreditation processes; peer and public review) to ensure the data and methodology it uses represent the best available science. For instance, the NAEMO model is the result of a NMFSled Center for Independent Experts (CIE) review of the components used in earlier models. The acoustic propagation component of the NAEMO model (CASS/GRAB) is accredited by the Oceanographic and Atmospheric Master Library (OAML), and many of the environmental variables used in the NAEMO model come from approved OAML databases and are based on insitu data collection. The animal density components of the NAEMO model are base products of the NMSDD, which includes animal density components that have been validated and reviewed by a variety of scientists from NMFS Science Centers and academic institutions. Several components of the model, for example the Duke University habitat-based density models, have been published in peer reviewed literature. Others like the Atlantic Marine Assessment Program for Protected Species, which was conducted by NMFS Science Centers, have undergone quality assurance and quality control (QA/QC) processes. Finally, the NAEMO model simulation components underwent QA/QC review and validation for model parts such as the scenario builder, acoustic builder, scenario simulator, etc., conducted by qualified statisticians and modelers to ensure accuracy. Other models and methodologies have gone through similar review processes. In summary, we believe the Navy’s methods, including the method for incorporating mitigation and avoidance, are the most appropriate methods for predicting PTS, tissue damage, TTS, and behavioral disruption. But even with the consideration of mitigation and avoidance, given some of the more conservative components of the methodology (e.g., the thresholds do not consider ear recovery between pulses), we would describe the application of these methods as identifying the maximum number of instances in which marine mammals would be reasonably expected to be taken through PTS, tissue damage, TTS, or behavioral disruption. E:\FR\FM\02JNP2.SGM 02JNP2 33982 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Summary of Requested Take From Training and Testing Activities Based on the methods discussed in the previous sections and the Navy’s model and quantitative assessment of mitigation, the Navy provided its take estimate and request for authorization of takes incidental to the use of acoustic and explosive sources for training and testing activities both annually (based on the maximum number of activities that could occur per 12-month period) and over the seven-year period covered by the Navy’s rulemaking/LOA application. The following species/ stocks present in the NWTT Study Area were modeled by the Navy and estimated to have 0 takes of any type from any activity source: Eastern North Pacific Northern Resident stock of killer whales, Western North Pacific stock of gray whales, and California stock of harbor seals. NMFS has reviewed the Navy’s data, methodology, and analysis and determined that it is complete and accurate. NMFS agrees that the estimates for incidental takes by harassment from all sources requested for authorization are the maximum number of instances in which marine mammals are reasonably expected to be taken. Estimated Harassment Take From Training and Testing Activities For training and testing activities, Tables 32 and 33 summarize the Navy’s take estimate and request and the annual and maximum amount and type of Level A harassment and Level B harassment for the seven-year period that NMFS concurs is reasonably expected to occur by species and stock. Note that take by Level B harassment includes both behavioral disruption and TTS. Tables 6–14–41 (sonar and other transducers) and 6–56–71 (explosives) in Section 6 of the Navy’s rulemaking/ LOA application provide the comparative amounts of TTS and behavioral disruption for each species and stock annually, noting that if a modeled marine mammal was ‘‘taken’’ through exposure to both TTS and behavioral disruption in the model, it was recorded as a TTS. TABLE 32—ANNUAL AND SEVEN-YEAR TOTAL SPECIES-SPECIFIC TAKE ESTIMATES PROPOSED FOR AUTHORIZATION FROM ACOUSTIC AND EXPLOSIVE SOUND SOURCE EFFECTS FOR ALL TRAINING ACTIVITIES IN THE NWTT STUDY AREA Annual Species 7-Year total Stock Level B Level A Level B Level A Order Cetacea Suborder Mysticeti (baleen whales) Family Balaenopteridae (rorquals): Blue whale * ............................... Fin whale * ................................. Sei whale * ................................. Minke whale ............................... Humpback whale * ..................... Family Eschrichtiidae (gray whale): Gray whale ................................. Eastern North Pacific ....................... Northeast Pacific .............................. California/Oregon/Washington ......... Eastern North Pacific ....................... Alaska ............................................... California/Oregon/Washington ......... Central North Pacific ........................ California/Oregon/Washington ......... 2 0 54 30 0 110 5 4 0 0 0 0 0 0 0 0 11 0 377 206 0 767 31 32 0 0 0 0 0 0 0 0 Eastern North Pacific ....................... 2 0 10 0 Suborder Odontoceti (toothed whales) Family Delphinidae (dolphins): Bottlenose dolphin ..................... Killer whale ................................ Northern right whale dolphin ..... Pacific white-sided dolphin ........ khammond on DSKJM1Z7X2PROD with PROPOSALS2 Risso’s dolphin ........................... Short-beaked common dolphin .. Short-finned pilot whale ............. Striped dolphin ........................... Family Kogiidae (Kogia species): Kogia species Pygmy ................ Family Phocoenidae (porpoises): Dall’s porpoise ........................... Harbor porpoise ......................... Family Physeteridae (sperm whale): Sperm whale * ............................ Family Ziphiidae (beaked whales): Baird’s beaked whale ................ Cuvier’s beaked whale .............. VerDate Sep<11>2014 21:30 Jun 01, 2020 California/Oregon/Washington Offshore. Alaska Resident ............................... Eastern North Pacific Offshore ........ West Coast Transient ...................... Southern Resident ✝ ......................... California/Oregon/Washington ......... North Pacific ..................................... California/Oregon/Washington ......... California/Oregon/Washington ......... California/Oregon/Washington ......... California/Oregon/Washington ......... California/Oregon/Washington ......... 5 0 33 0 0 68 78 3 7,941 0 5,284 2,286 1,165 57 439 0 0 0 0 0 0 0 0 0 0 0 0 478 538 15 55,493 0 36,788 15,972 8,124 398 3,059 0 0 0 0 0 0 0 0 0 0 0 California/Oregon/Washington ......... 381 0 2,664 0 Alaska ............................................... California/Oregon/Washington ......... Southeast Alaska ............................. Northern Oregon/Washington Coast Northern California/Southern Oregon. Washington Inland Waters ............... 0 13,299 0 299 21 0 8 0 0 0 0 92,793 0 2,092 145 0 48 0 0 0 12,315 43 79,934 291 California/Oregon/Washington ......... 512 0 3,574 0 California/Oregon/Washington ......... California/Oregon/Washington ......... 556 1,462 0 0 3,875 10,209 0 0 Jkt 250001 PO 00000 Frm 00070 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 33983 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 32—ANNUAL AND SEVEN-YEAR TOTAL SPECIES-SPECIFIC TAKE ESTIMATES PROPOSED FOR AUTHORIZATION FROM ACOUSTIC AND EXPLOSIVE SOUND SOURCE EFFECTS FOR ALL TRAINING ACTIVITIES IN THE NWTT STUDY AREA— Continued Annual Species 7-Year total Stock Level B Mesoplodon species .................. California/Oregon/Washington ......... Level A Level B Level A 652 0 4,549 0 U.S. Stock ........................................ Eastern U.S. ..................................... Mexico .............................................. Eastern Pacific ................................. California .......................................... 3,624 108 608 2,134 43 0 0 0 0 0 25,243 743 4,247 14,911 300 0 0 0 0 0 Southeast Alaska—Clarence Strait .. Oregon/Washington Coastal ............ Washington Northern Inland Waters Hood Canal ...................................... Southern Puget Sound ..................... California .......................................... 0 0 669 2,686 1,090 1,909 0 0 5 1 1 1 0 0 3,938 18,662 6,657 13,324 0 0 35 5 6 1 Suborder Pinnipedia Family Otariidae (sea lions and fur seals): California sea lion ...................... Steller sea lion ........................... Guadalupe fur seal ∗ .................. Northern fur seal ........................ Family Phocidae (true seals): Harbor seal ................................ Northern elephant seal .............. * ESA-listed species (all stocks) within the NWTT Study Area. ✝ Only designated stocks are ESA-listed. TABLE 33—ANNUAL AND SEVEN-YEAR TOTAL SPECIES-SPECIFIC TAKE ESTIMATES PROPOSED FOR AUTHORIZATION FROM ACOUSTIC AND EXPLOSIVE SOUND SOURCE EFFECTS FOR ALL TRAINING ACTIVITIES IN THE NWTT STUDY AREA Annual Species 7-Year total Stock Level B Level A Level B Level A Order Cetacea Suborder Mysticeti (baleen whales) Family Balaenopteridae (rorquals): Blue whale ∗ ............................... Fin whale ∗ ................................. Sei whale ∗ ................................. Minke whale ............................... Humpback whale ∗ ..................... Family Eschrichtiidae (gray whale): Gray whale ................................. Eastern North Pacific ....................... Northeast Pacific .............................. California/Oregon/Washington ......... Eastern North Pacific ....................... Alaska ............................................... California/Oregon/Washington ......... Central North Pacific ........................ California/Oregon/Washington ......... 8 2 81 53 2 192 110 89 0 0 0 0 0 0 0 0 38 10 392 258 9 916 578 460 0 0 0 0 0 0 0 0 Eastern North Pacific ....................... 41 0 189 0 Suborder Odontoceti (toothed whales) Family Delphinidae (dolphins): Bottlenose dolphin ..................... Killer whale ................................ khammond on DSKJM1Z7X2PROD with PROPOSALS2 Northern right whale dolphin ..... Pacific white-sided dolphin ........ Risso’s dolphin ........................... Short-beaked common dolphin .. Short-finned pilot whale ............. Striped dolphin ........................... Family Kogiidae (Kogia species): Kogia species ............................ Family Phocoenidae (porpoises): Dall’s porpoise ........................... Harbor porpoise ......................... VerDate Sep<11>2014 21:30 Jun 01, 2020 California/Oregon/Washington Offshore. Alaska Resident ............................... Eastern North Pacific Offshore ........ West Coast Transient ...................... Southern Resident ✝ ......................... California/Oregon/Washington ......... North Pacific ..................................... California/Oregon/Washington ......... California/Oregon/Washington ......... California/Oregon/Washington ......... California/Oregon/Washington ......... California/Oregon/Washington ......... 3 0 14 0 34 89 154 48 13,759 101 15,681 4,069 984 31 344 0 0 0 0 1 0 1 0 0 0 0 202 412 831 228 66,457 603 76,980 19,637 3,442 126 1,294 0 0 0 0 7 0 8 0 0 0 0 California/Oregon/Washington ......... 501 1 2,376 9 Alaska ............................................... California/Oregon/Washington ......... Southeast Alaska ............................. Northern Oregon/Washington Coast 638 20,398 130 52,113 0 90 0 103 3,711 98,470 794 265,493 0 523 0 525 Jkt 250001 PO 00000 Frm 00071 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 33984 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 33—ANNUAL AND SEVEN-YEAR TOTAL SPECIES-SPECIFIC TAKE ESTIMATES PROPOSED FOR AUTHORIZATION FROM ACOUSTIC AND EXPLOSIVE SOUND SOURCE EFFECTS FOR ALL TRAINING ACTIVITIES IN THE NWTT STUDY AREA— Continued Annual Species 7-Year total Stock Level B Family Physeteridae (sperm whale): Sperm whale * ............................ Family Ziphiidae (beaked whales): Baird’s beaked whale ................ Cuvier’s beaked whale .............. Mesoplodon species .................. Level A Level B Level A Northern California/Southern Oregon. Washington Inland Waters ............... 2,018 86 12,131 432 17,228 137 115,770 930 California/Oregon/Washington ......... 327 0 1,443 0 California/Oregon/Washington ......... California/Oregon/Washington ......... California/Oregon/Washington ......... 420 1,077 470 0 0 0 1,738 4,979 2,172 0 0 0 U.S. Stock ........................................ Eastern U.S. ..................................... Mexico .............................................. Eastern Pacific ................................. California .......................................... 20,474 2,130 887 9,458 189 1 0 0 0 0 93,906 10,745 4,022 45,813 920 5 0 0 0 0 Southeast Alaska—Clarence Strait .. Oregon/Washington Coastal ............ Washington Northern Inland Waters Hood Canal ...................................... Southern Puget Sound ..................... California .......................................... 2,352 1,180 578 58,784 5,748 2,935 0 2 0 0 3 3 13,384 6,222 3,227 396,883 39,511 14,120 0 11 0 0 24 18 Suborder Pinnipedia Family Otariidae (sea lions and fur seals): California sea lion ...................... Steller sea lion ........................... Guadalupe fur seal * .................. Northern fur seal ........................ Family Phocidae (true seals): Harbor seal ................................ Northern elephant seal .............. khammond on DSKJM1Z7X2PROD with PROPOSALS2 * ESA-listed species (all stocks) within the NWTT Study Area. ✝ Only designated stocks are ESA-listed. Estimated Take From Vessel Strikes by Serious Injury or Mortality Vessel strikes from commercial, recreational, and military vessels are known to affect large whales and have resulted in serious injury and occasional fatalities to cetaceans (BermanKowalewski et al., 2010; Calambokidis, 2012; Douglas et al., 2008; Laggner 2009; Lammers et al., 2003). Records of collisions date back to the early 17th century, and the worldwide number of collisions appears to have increased steadily during recent decades (Laist et al., 2001; Ritter 2012). Numerous studies of interactions between surface vessels and marine mammals have demonstrated that freeranging marine mammals often, but not always (e.g., McKenna et al., 2015), engage in avoidance behavior when surface vessels move toward them. It is not clear whether these responses are caused by the physical presence of a surface vessel, the underwater noise generated by the vessel, or an interaction between the two (Amaral and Carlson, 2005; Au and Green, 2000; Bain et al., 2006; Bauer 1986; Bejder et al., 1999; Bejder and Lusseau, 2008; Bejder et al., 2009; Bryant et al., 1984; Corkeron, 1995; Erbe, 2002; Fe´lix, 2001; Goodwin and Cotton, 2004; Lemon et VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 al., 2006; Lusseau, 2003; Lusseau, 2006; Magalhaes et al., 2002; Nowacek et al., 2001; Richter et al., 2003; Scheidat et al., 2004; Simmonds, 2005; Watkins, 1986; Williams et al., 2002; Wursig et al., 1998). Several authors suggest that the noise generated during motion is probably an important factor (Blane and Jaakson, 1994; Evans et al., 1992; Evans et al., 1994). Water disturbance may also be a factor. These studies suggest that the behavioral responses of marine mammals to surface vessels are similar to their behavioral responses to predators. Avoidance behavior is expected to be even stronger in the subset of instances during which the Navy is conducting training or testing activities using active sonar or explosives. The marine mammals most vulnerable to vessel strikes are those that spend extended periods of time at the surface in order to restore oxygen levels within their tissues after deep dives (e.g., sperm whales). In addition, some baleen whales seem generally unresponsive to vessel sound, making them more susceptible to vessel collisions (Nowacek et al., 2004). These species are primarily large, slow moving whales. PO 00000 Frm 00072 Fmt 4701 Sfmt 4702 Some researchers have suggested the relative risk of a vessel strike can be assessed as a function of animal density and the magnitude of vessel traffic (e.g., Fonnesbeck et al., 2008; Vanderlaan et al., 2008). Differences among vessel types also influence the probability of a vessel strike. The ability of any ship to detect a marine mammal and avoid a collision depends on a variety of factors, including environmental conditions, ship design, size, speed, and ability and number of personnel observing, as well as the behavior of the animal. Vessel speed, size, and mass are all important factors in determining if injury or death of a marine mammal is likely due to a vessel strike. For large vessels, speed and angle of approach can influence the severity of a strike. For example, Vanderlaan and Taggart (2007) found that between vessel speeds of 8.6 and 15 knots, the probability that a vessel strike is lethal increases from 0.21 to 0.79. Large whales also do not have to be at the water’s surface to be struck. Silber et al. (2010) found when a whale is below the surface (about one to two times the vessel draft), under certain circumstances (vessel speed and location of the whale relative to the ship’s centerline), there is likely to be a pronounced propeller suction effect. E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules This suction effect may draw the whale into the hull of the ship, increasing the probability of propeller strikes. There are some key differences between the operation of military and non-military vessels, which make the likelihood of a military vessel striking a whale lower than some other vessels (e.g., commercial merchant vessels). Key differences include: • Many military ships have their bridges positioned closer to the bow, offering better visibility ahead of the ship (compared to a commercial merchant vessel); • There are often aircraft associated with the training or testing activity (which can serve as Lookouts), which can more readily detect cetaceans in the vicinity of a vessel or ahead of a vessel’s present course before crew on the vessel would be able to detect them; • Military ships are generally more maneuverable than commercial merchant vessels, and if cetaceans are spotted in the path of the ship, could be capable of changing course more quickly; • The crew size on military vessels is generally larger than merchant ships, allowing for stationing more trained Lookouts on the bridge. At all times when Navy vessels are underway, trained Lookouts and bridge navigation teams are used to detect objects on the surface of the water ahead of the ship, including cetaceans. Additional Lookouts, beyond those already stationed on the bridge and on navigation teams, are positioned as Lookouts during some training events; and • When submerged, submarines are generally slow moving (to avoid detection) and therefore marine mammals at depth with a submarine are likely able to avoid collision with the submarine. When a submarine is transiting on the surface, there are Lookouts serving the same function as they do on surface ships. Vessel strike to marine mammals is not associated with any specific training or testing activity but is rather an extremely limited and sporadic, but possible, accidental result of Navy vessel movement within the NWTT Study Area or while in transit. Data from the ports of Vancouver, British Columbia; Seattle, Washington; and Tacoma, Washington indicate there were more than 7,000 commercial vessel transits in 2017 associated with visits to just those ports (The Northwest Seaport Alliance, 2018; Vancouver Fraser Port Authority). This number of vessel transits does not account for other vessel traffic in the Strait of Juan de Fuca or Puget Sound including VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 commercial ferries, tourist vessels, or recreational vessels. Additional commercial traffic in the NWTT Study Area also includes vessels transiting offshore along the Pacific coast, bypassing ports in Canada and Washington; traffic associated with ports to the south along the coast of Washington and in Oregon; and vessel traffic in Southeast Alaska (Nuka Research & Planning Group, 2012). Navy vessel traffic accounts for only a small portion of vessel activities in the NWTT Study Area. The Navy has, in total, the following homeported operational vessels: 2 Aircraft carriers, 6 destroyers, 14 submarines, and 22 smaller security vessels with a combined annual total of 241 Navy vessel transits (see Appendix A (Navy Activities Descriptions) of the 2019 DSEIS/OEIS for descriptions of the number of vessels used during the various types of Navy’s proposed activities). Activities involving military vessel movement would be widely dispersed throughout the NWTT Study Area. Navy vessel strike records have been kept since 1995, and since 1995 there have been two recorded strikes of whales by Navy vessels (or vessels being operated on behalf of the Navy) in the NWTT Study Area. Neither strike was associated with training or testing activities. The first strike occurred in 2012 by a Navy destroyer off the southern coast of Oregon while in transit to San Diego. The whale was suspected to be a minke whale due to the appearance and size (25 ft, dark with white belly), however the Navy could not rule out the possibility that it was a juvenile fin whale. The whale was observed swimming after the strike and no blood or injury was sighted. The second strike occurred in 2016 by a U.S. Coast Guard cutter operating on behalf of the Navy as part of a Maritime Security Operation escort vessel in the Strait of Juan de Fuca. The whale was positively identified as a humpback whale. It was observed for 10 minutes post-collision and appeared normal at the surface. There was no blood observed in the water and the whale subsequently swam away. In order to account for the potential risk from vessel movement within the NWTT Study Area within the sevenyear period in particular, the Navy requested incidental takes based on probabilities derived from a Poisson distribution using ship strike data between 2009–2018 in the NWTT Study Area (the time period from when current mitigation measures to reduce the likelihood of vessel strikes were instituted until the Navy conducted the analysis for the Navy’s application), as PO 00000 Frm 00073 Fmt 4701 Sfmt 4702 33985 well as historical at-sea days in the NWTT Study Area from 2009–2018 and estimated potential at-sea days for the period from 2020 to 2027 covered by the requested regulations. This distribution predicted the probabilities of a specific number of strikes (n = 0, 1, 2, etc.) over the period from 2020 to 2027. The analysis for the period of 2020 to 2027 is described in detail in Chapter 6.6 (Vessel Strike Analysis) of the Navy’s rulemaking/LOA application. For the same reasons listed above, describing why a Navy vessel strike is comparatively unlikely, it is highly unlikely that a Navy vessel would strike a whale, dolphin, porpoise, or pinniped without detecting it and, accordingly, NMFS is confident that the Navy’s reported strikes are accurate and appropriate for use in the analysis. Specifically, Navy ships have multiple Lookouts, including on the forward part of the ship that can visually detect a hit animal, in the unlikely event ship personnel do not feel the strike. Unlike the situation for non-Navy ships engaged in commercial activities, NMFS and the Navy have no evidence that the Navy has struck a whale and not detected it. Navy’s strict internal procedures and mitigation requirements include reporting of any vessel strikes of marine mammals, and the Navy’s discipline, extensive training (not only for detecting marine mammals, but for detecting and reporting any potential navigational obstruction), and strict chain of command give NMFS a high level of confidence that all strikes actually get reported. The Navy used those two whale strikes in their calculations to determine the number of strikes likely to result from their activities and evaluated data beginning in 2009. The Navy’s Marine Species Awareness Training was first used in 2006 and was fully integrated across the Navy in 2009, which is why the Navy uses 2009 as the date to begin the analysis. The adoption of additional mitigation measures to address ship strike also began in 2009, and will remain in place along with additional mitigation measures during the seven years of this rule. The probability analysis concluded that there was a 26 percent chance that zero whales would be struck by Navy vessels over the seven-year period, and a 35, 24, 11, and 4 percent chance that one, two, three, or four whales, respectively, would be struck over the seven-year period (with a 74 percent chance total that at least one whale would be struck over the seven-year period). Therefore, the Navy estimates, and NMFS agrees, that there is some probability that the Navy could strike, and take by serious injury or E:\FR\FM\02JNP2.SGM 02JNP2 33986 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules mortality, up to three large whales incidental to training and testing activities within the NWTT Study Area over the course of the seven years. Small whales, delphinids, porpoises, and pinnipeds are not expected to be struck by Navy vessels. In addition to the reasons listed above that make it unlikely that the Navy will hit a large whale (more maneuverable ships, larger crew, etc.), the following are the additional reasons that vessel strike of dolphins, small whales, porpoises, and pinnipeds is considered very unlikely. Dating back more than 20 years and for as long as it has kept records, the Navy has no records of individuals of these groups being struck by a vessel as a result of Navy activities and, further, their smaller size and maneuverability make a strike unlikely. Also, NMFS has never received any reports from other authorized activities indicating that these species have been struck by vessels. Worldwide ship strike records show little evidence of strikes of these groups from the shipping sector and larger vessels and the majority of the Navy’s activities involving fastermoving vessels (that could be considered more likely to hit a marine mammal) are located in offshore areas where smaller delphinid, porpoise, and pinniped densities are lower. Based on this information, NMFS concurs with the Navy’s assessment and recognizes the potential for incidental take by vessel strike of large whales only (i.e., no dolphins, small whales, porpoises, or pinnipeds) over the course of the sevenyear regulations from training and testing activities. Taking into account the available information regarding how many of any given stock could be struck and therefore should be authorized for take, NMFS considered three factors in addition to those considered in the Navy’s request: (1) The relative likelihood of hitting one stock versus another based on available strike data from all vessel types as denoted in the SARs, (2) whether the Navy has ever definitively struck an individual from a particular species or stock in the NWTT Study Area, and if so, how many times, and (3) whether there are records that an individual from a particular species or stock has been struck by any vessel in the NWTT Study Area, and if so, how many times (based on ship strike records provided by the NMFS West Coast Region in February 2020). To address number (1) above, NMFS compiled information from NMFS’ SARs on detected annual rates of large whale serious injury or mortality (M/SI) from vessel collisions (Table 34). The annual rates of large whale serious injury or mortality from vessel collisions from the SARs help inform the relative susceptibility of large whale species to vessel strike in NWTT Study Area as recorded systematically over the last five years (the period used for the SARs). However, we note that the SARs present strike data from the stock’s entire range, which is much larger than the NWTT Study Area, and available ship strike records show that the majority of strikes that occur off the United States West Coast occur in southern California. We summed the annual rates of serious injury or mortality from vessel collisions as reported in the SARs, then divided each species’ annual rate by this sum to get the proportion of strikes for each species/stock. To inform the likelihood of striking a particular species of large whale, we multiplied the proportion of striking each species by the probability of striking at least one whale (i.e., 74 percent, as described by the Navy’s probability analysis above). We note that these probabilities vary from year to year as the average annual mortality for a given five-year window in the SAR changes; however, over the years and through changing SARs, stocks tend to consistently maintain a relatively higher or relatively lower likelihood of being struck (and we include the annual averages from 2017 SARs in Table 34 to illustrate). The probabilities calculated as described above are then considered in combination with the information indicating the species that the Navy has definitively hit in the NWTT Study Area since 1995 (since they started tracking consistently) and the species that are known to have been struck by any vessel (through regional stranding data) in the NWTT Study Area. We also note that Rockwood et al. (2017) modeled the likely vessel strike of blue whales, fin whales, and humpback whales on the U.S. West Coast (discussed in more detail in the Serious Injury or Mortality subsection of the Preliminary Analysis and Negligible Impact Determination section), and those numbers help inform the relative likelihood that the Navy will hit those stocks. For each indicated stock, Table 34 includes the percent likelihood of hitting an individual whale once based on SAR data, total strikes from Navy vessels (from 1995), total strikes from any vessel (from 2000 from regional stranding data), and modeled vessel strikes from Rockwood et al. (2017). The last column indicates the annual serious injury or mortality proposed for authorization. TABLE 34—SUMMARY OF FACTORS CONSIDERED IN DETERMINING THE NUMBER OF INDIVIDUALS IN EACH STOCK POTENTIALLY STRUCK BY A VESSEL ESA status Species Stock Listed .......... Blue whale ............... Fin whale ................. Eastern North Pacific ..................... Northeast Pacific ............................ CA/OR/WA ..................................... Eastern North Pacific ..................... CA/OR/WA (Mexico and Central America DPS). CA/OR/WA ..................................... Alaska ............................................ CA/OR/WA ..................................... Eastern North Pacific ..................... Central North Pacific (Hawaii DPS) khammond on DSKJM1Z7X2PROD with PROPOSALS2 Sei whale ................. Humpback whale ..... Not Listed ... Sperm whale ........... Minke whale ............ Gray whale .............. Humpback whale ..... Annual rate of M/SI from vessel collision (observed from 2017 SARs) Annual rate of M/SI from vessel collision (observed from 2019 Draft SARs) Percent likelihood of hitting individual from species/ stock once (from 2019 Draft SARs) Total known strikes in OR, WA, northern CA (from 2000 to present) 1 0 0.2 1.8 0 1.1 0.4 0.4 1.6 0.2 2.1 3.7 3.7 14.8 1.85 19.425 2 10 0.2 0 0 2 2.6 0 0 0 0.8 2.5 0 0 0 7.4 23.125 Total known navy strikes in NWTT study area Rockwood et al. (2017) modeled vessel strikes 5 MMPA proposed authorized takes (from the 3 total) 18 0 2 2 0 2 0 0.29 0.29 0 0.29 1 0 1 1 2 0.14 0 0.14 0.14 0.29 2 10 34 43 41 3 1 9 34 1 41 1 Only 22 Annual proposed authorized take one ship strike was reported in California in the NWTT Study Area (which is limited to Humbolt and Del Norte Counties). This strike occurred in 2004 in Humbolt County and was not identified to species. 2 A total of 10 fin whale strikes are reported in the regional stranding database, however no information on stock is provided. As these two stocks of fin whales are known to overlap spatially and temporally in the NWTT Study Area, the 10 reported strikes could come from either stock or a combination of both stocks. 3 A total of 4 humpback whales strikes are reported in the regional stranding database, however no information on stock is provided. As these two stocks of humpback whales are known to overlap spatially and temporally in the NWTT Study Area, the 4 reported strikes could come from either stock or a combination of both stocks. 4 One humpback whale was reported as struck by a U.S. Coast Guard cutter operating on behalf of the Navy, however it was not possible for the Navy to determine which stock this whale came from. As these two stocks of humpback whales are known to overlap spatially and temporally in the NWTT Study Area, this whale could have come from either stock. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00074 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 5 Rockwood 33987 et al. modeled likely annual vessel strikes off the West Coast for these three species only. Accordingly, stocks that have no record of having been struck by any vessel are considered unlikely to be struck by the Navy in the seven-year period of the rule. Stocks that have never been struck by the Navy, have rarely been struck by other vessels, and have a low likelihood of being struck based on the SAR calculation and a low relative abundance (Eastern North Pacific stock of blue whales, Eastern North Pacific stock of sei whales, and Alaska stock of minke whales) are also considered unlikely to be struck by the Navy during the seven-year rule. This rules out all but seven stocks. The two stocks of humpback whales (CA/OR/WA and Central North Pacific) and two stocks of fin whales (CA/OR/ WA and Northeast Pacific) are known to overlap spatially and temporally in the NWTT Study Area, and it is not possible to distinguish the difference between individuals of these stocks based on visual sightings in the field. The Navy has previously struck a humpback whale in the NWTT Study Area and it is the second most common species struck by any vessel in the Study Area based on stranding data. Based on the SAR data, the two stocks of humpback whales also have the highest likelihood of being struck. Though the Navy has not definitively struck a fin whale in the NWTT Study Area (noting that the Navy could not rule out that the minke whale strike could have been a juvenile fin whale), fin whales are the most common species struck by any vessel in the Study Area based on stranding data. Based on the SAR data, the CA/OR/WA stock has the third highest likelihood of being struck. Based on all of these factors, it is considered reasonably likely that humpback whales (from either the CA/OR/WA or Central North Pacific stocks) could be struck twice and fin whales (from either the CA/OR/WA or Northeast Pacific stocks) could be struck twice during the seven-year rule. Based on the SAR data, the CA/OR/ WA stock of sperm whales and CA/OR/ WA stock of minke whales have a very low likelihood of being struck. However, 3 sperm whales have been struck by non-Navy vessels in the NWTT Study Area (in 2002, 2007, and 2012) and the Navy has previously struck a minke whale in the NWTT Study Area. Therefore, we consider it reasonable to predict that an individual from each of these stocks could be struck by the Navy once during the seven-year rule. Finally, based on stranding data, gray whales are the second most commonly struck whale in VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 the NWTT Study Area and the SAR data indicates that on average, 0.8 whales from this stock are struck throughout the stock’s range each year. Based on these data, we consider it reasonable to predict that an individual from the Eastern North Pacific stock of gray whales could be struck by the Navy once during the seven-year rule. In conclusion, although it is generally unlikely that any whales will be struck in a year, based on the information and analysis above, NMFS anticipates that no more than three whales have the potential to be taken by serious injury or mortality over the seven-year period of the rule. Of those three whales over the seven years, no more than two may come from any of the following species/ stocks: Fin whale (which may come from either the Northeast Pacific or CA/ OR/WA stock) and humpback whale (which may come from either the Central North Pacific or CA/OR/WA stock). Additionally, of those three whales over the seven years no more than one may come from any of the following species/stocks: Sperm whale (CA/OR/WA stock), minke whale (CA/ OR/WA stock), and gray whale (Eastern North Pacific stock). Accordingly, NMFS has evaluated under the negligible impact standard the M/SI of 0.14 or 0.29 whales annually from each of these species or stocks (i.e., 1 or 2 takes, respectively, divided by seven years to get the annual number), along with the expected incidental takes by harassment. We do not anticipate, nor propose to authorize, ship strike takes to blue whales (Eastern North Pacific stock), minke whales (Alaska stock), or sei whales (Eastern North Pacific stock). Proposed Mitigation Measures Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the permissible methods of taking pursuant to the activity, and other means of effecting the least practicable adverse impact on the species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and on the availability of the species or stocks for subsistence uses (‘‘least practicable adverse impact’’). NMFS does not have a regulatory definition for least practicable adverse impact. The 2004 NDAA amended the MMPA as it relates to military readiness activities and the incidental take authorization process such that a determination of ‘‘least practicable adverse impact’’ shall include consideration of personnel safety, practicality of implementation, PO 00000 Frm 00075 Fmt 4701 Sfmt 4702 and impact on the effectiveness of the military readiness activity. In Conservation Council for Hawaii v. National Marine Fisheries Service, 97 F. Supp. 3d 1210, 1229 (D. Haw. 2015), the Court stated that NMFS ‘‘appear[s] to think [it] satisf[ies] the statutory ‘least practicable adverse impact’ requirement with a ‘negligible impact’ finding.’’ More recently, expressing similar concerns in a challenge to a U.S. Navy Surveillance Towed Array Sensor System Low Frequency Active Sonar (SURTASS LFA) incidental take rule (77 FR 50290), the Ninth Circuit Court of Appeals in Natural Resources Defense Council (NRDC) v. Pritzker, 828 F.3d 1125, 1134 (9th Cir. 2016), stated, ‘‘[c]ompliance with the ‘negligible impact’ requirement does not mean there [is] compliance with the ‘least practicable adverse impact’ standard.’’ As the Ninth Circuit noted in its opinion, however, the Court was interpreting the statute without the benefit of NMFS’ formal interpretation. We state here explicitly that NMFS is in full agreement that the ‘‘negligible impact’’ and ‘‘least practicable adverse impact’’ requirements are distinct, even though both statutory standards refer to species and stocks. With that in mind, we provide further explanation of our interpretation of least practicable adverse impact, and explain what distinguishes it from the negligible impact standard. This discussion is consistent with previous rules we have published, such as the Navy’s HawaiiSouthern California Training and Testing (HSTT) rule (83 FR 66846; December 27, 2018), Atlantic Fleet Training and Testing (AFTT) rule (84 FR 70712; December 23, 2019), and Mariana Islands Training and Testing (MITT) proposed rule (85 FR 5782; January 31, 2020). Before NMFS can issue incidental take regulations under section 101(a)(5)(A) of the MMPA, it must make a finding that the total taking will have a ‘‘negligible impact’’ on the affected ‘‘species or stocks’’ of marine mammals. NMFS’ and U.S. Fish and Wildlife Service’s implementing regulations for section 101(a)(5) both define ‘‘negligible impact’’ as an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival (50 CFR 216.103 and 50 CFR 18.27(c)). Recruitment (i.e., reproduction) and survival rates are used to determine E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33988 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules population growth rates 3 and, therefore are considered in evaluating population level impacts. As stated in the preamble to the proposed rule for the MMPA incidental take implementing regulations, not every population-level impact violates the negligible impact requirement. The negligible impact standard does not require a finding that the anticipated take will have ‘‘no effect’’ on population numbers or growth rates: The statutory standard does not require that the same recovery rate be maintained, rather that no significant effect on annual rates of recruitment or survival occurs. The key factor is the significance of the level of impact on rates of recruitment or survival. (54 FR 40338, 40341–42; September 29, 1989). While some level of impact on population numbers or growth rates of a species or stock may occur and still satisfy the negligible impact requirement—even without consideration of mitigation—the least practicable adverse impact provision separately requires NMFS to prescribe means of effecting the least practicable adverse impact on such species or stock and its habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, 50 CFR 216.102(b), which are typically identified as mitigation measures.4 The negligible impact and least practicable adverse impact standards in the MMPA both call for evaluation at the level of the ‘‘species or stock.’’ The MMPA does not define the term ‘‘species.’’ However, Merriam-Webster Dictionary defines ‘‘species’’ to include ‘‘related organisms or populations potentially capable of interbreeding.’’ See www.merriam-webster.com/ dictionary/species (emphasis added). Section 3(11) of the MMPA defines ‘‘stock’’ as a group of marine mammals of the same species or smaller taxa in a common spatial arrangement that interbreed when mature. The definition of ‘‘population’’ is a group of interbreeding organisms that represents the level of organization at which speciation begins. www.merriamwebster.com/dictionary/population. The definition of ‘‘population’’ is strikingly similar to the MMPA’s definition of ‘‘stock,’’ with both involving groups of individuals that belong to the same species and located in a manner that allows for interbreeding. In fact under MMPA section 3(11), the term ‘‘stock’’ 3A growth rate can be positive, negative, or flat. purposes of this discussion, we omit reference to the language in the standard for least practicable adverse impact that says we also must mitigate for subsistence impacts because they are not at issue in this rule. 4 For VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 in the MMPA is interchangeable with the statutory term ‘‘population stock.’’ Both the negligible impact standard and the least practicable adverse impact standard call for evaluation at the level of the species or stock, and the terms ‘‘species’’ and ‘‘stock’’ both relate to populations; therefore, it is appropriate to view both the negligible impact standard and the least practicable adverse impact standard as having a population-level focus. This interpretation is consistent with Congress’ statutory findings for enacting the MMPA, nearly all of which are most applicable at the species or stock (i.e., population) level. See MMPA section 2 (finding that it is species and population stocks that are or may be in danger of extinction or depletion; that it is species and population stocks that should not diminish beyond being significant functioning elements of their ecosystems; and that it is species and population stocks that should not be permitted to diminish below their optimum sustainable population level). Annual rates of recruitment (i.e., reproduction) and survival are the key biological metrics used in the evaluation of population-level impacts, and accordingly these same metrics are also used in the evaluation of population level impacts for the least practicable adverse impact standard. Recognizing this common focus of the least practicable adverse impact and negligible impact provisions on the ‘‘species or stock’’ does not mean we conflate the two standards; despite some common statutory language, we recognize the two provisions are different and have different functions. First, a negligible impact finding is required before NMFS can issue an incidental take authorization. Although it is acceptable to use the mitigation measures to reach a negligible impact finding (see 50 CFR 216.104(c)), no amount of mitigation can enable NMFS to issue an incidental take authorization for an activity that still would not meet the negligible impact standard. Moreover, even where NMFS can reach a negligible impact finding—which we emphasize does allow for the possibility of some ‘‘negligible’’ population-level impact—the agency must still prescribe measures that will affect the least practicable amount of adverse impact upon the affected species or stock. Section 101(a)(5)(A)(i)(II) requires NMFS to issue, in conjunction with its authorization, binding—and enforceable—restrictions (in the form of regulations) setting forth how the activity must be conducted, thus ensuring the activity has the ‘‘least practicable adverse impact’’ on the PO 00000 Frm 00076 Fmt 4701 Sfmt 4702 affected species or stocks. In situations where mitigation is specifically needed to reach a negligible impact determination, section 101(a)(5)(A)(i)(II) also provides a mechanism for ensuring compliance with the ‘‘negligible impact’’ requirement. Finally, the least practicable adverse impact standard also requires consideration of measures for marine mammal habitat, with particular attention to rookeries, mating grounds, and other areas of similar significance, and for subsistence impacts, whereas the negligible impact standard is concerned solely with conclusions about the impact of an activity on annual rates of recruitment and survival.5 In NRDC v. Pritzker, the Court stated, ‘‘[t]he statute is properly read to mean that even if population levels are not threatened significantly, still the agency must adopt mitigation measures aimed at protecting marine mammals to the greatest extent practicable in light of military readiness needs.’’ Pritzker at 1134 (emphases added). This statement is consistent with our understanding stated above that even when the effects of an action satisfy the negligible impact standard (i.e., in the Court’s words, ‘‘population levels are not threatened significantly’’), still the agency must prescribe mitigation under the least practicable adverse impact standard. However, as the statute indicates, the focus of both standards is ultimately the impact on the affected ‘‘species or stock,’’ and not solely focused on or directed at the impact on individual marine mammals. We have carefully reviewed and considered the Ninth Circuit’s opinion in NRDC v. Pritzker in its entirety. While the Court’s reference to ‘‘marine mammals’’ rather than ‘‘marine mammal species or stocks’’ in the italicized language above might be construed as holding that the least practicable adverse impact standard applies at the individual ‘‘marine mammal’’ level, i.e., that NMFS must require mitigation to minimize impacts to each individual marine mammal unless impracticable, we believe such an interpretation reflects an incomplete appreciation of the Court’s holding. In our view, the opinion as a whole turned on the Court’s determination that NMFS had not given separate and independent meaning to the least practicable adverse impact standard apart from the negligible impact standard, and further, that the Court’s use of the term ‘‘marine mammals’’ was not addressing the 5 Outside of the military readiness context, mitigation may also be appropriate to ensure compliance with the ‘‘small numbers’’ language in MMPA sections 101(a)(5)(A) and (D). E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules question of whether the standard applies to individual animals as opposed to the species or stock as a whole. We recognize that while consideration of mitigation can play a role in a negligible impact determination, consideration of mitigation measures extends beyond that analysis. In evaluating what mitigation measures are appropriate, NMFS considers the potential impacts of the Specified Activities, the availability of measures to minimize those potential impacts, and the practicability of implementing those measures, as we describe below. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Implementation of Least Practicable Adverse Impact Standard Given the NRDC v. Pritzker decision, we discuss here how we determine whether a measure or set of measures meets the ‘‘least practicable adverse impact’’ standard. Our separate analysis of whether the take anticipated to result from Navy’s activities meets the ‘‘negligible impact’’ standard appears in the Preliminary Analysis and Negligible Impact Determination section below. Our evaluation of potential mitigation measures includes consideration of two primary factors: (1) The manner in which, and the degree to which, implementation of the potential measure(s) is expected to reduce adverse impacts to marine mammal species or stocks, their habitat, and their availability for subsistence uses (where relevant). This analysis considers such things as the nature of the potential adverse impact (such as likelihood, scope, and range), the likelihood that the measure will be effective if implemented, and the likelihood of successful implementation; and (2) The practicability of the measures for applicant implementation. Practicability of implementation may consider such things as cost, impact on activities, and, in the case of a military readiness activity, specifically considers personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. While the language of the least practicable adverse impact standard calls for minimizing impacts to affected species or stocks, we recognize that the reduction of impacts to those species or stocks accrues through the application of mitigation measures that limit impacts to individual animals. Accordingly, NMFS’ analysis focuses on measures that are designed to avoid or minimize impacts on individual marine mammals that are likely to increase the VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 probability or severity of populationlevel effects. While direct evidence of impacts to species or stocks from a specified activity is rarely available, and additional study is still needed to understand how specific disturbance events affect the fitness of individuals of certain species, there have been improvements in understanding the process by which disturbance effects are translated to the population. With recent scientific advancements (both marine mammal energetic research and the development of energetic frameworks), the relative likelihood or degree of impacts on species or stocks may often be inferred given a detailed understanding of the activity, the environment, and the affected species or stocks—and the best available science has been used here. This same information is used in the development of mitigation measures and helps us understand how mitigation measures contribute to lessening effects (or the risk thereof) to species or stocks. We also acknowledge that there is always the potential that new information, or a new recommendation could become available in the future and necessitate reevaluation of mitigation measures (which may be addressed through adaptive management) to see if further reductions of population impacts are possible and practicable. In the evaluation of specific measures, the details of the specified activity will necessarily inform each of the two primary factors discussed above (expected reduction of impacts and practicability), and are carefully considered to determine the types of mitigation that are appropriate under the least practicable adverse impact standard. Analysis of how a potential mitigation measure may reduce adverse impacts on a marine mammal stock or species, consideration of personnel safety, practicality of implementation, and consideration of the impact on effectiveness of military readiness activities are not issues that can be meaningfully evaluated through a yes/ no lens. The manner in which, and the degree to which, implementation of a measure is expected to reduce impacts, as well as its practicability in terms of these considerations, can vary widely. For example, a time/area restriction could be of very high value for decreasing population-level impacts (e.g., avoiding disturbance of feeding females in an area of established biological importance) or it could be of lower value (e.g., decreased disturbance in an area of high productivity but of less biological importance). Regarding practicability, a measure might involve PO 00000 Frm 00077 Fmt 4701 Sfmt 4702 33989 restrictions in an area or time that impede the Navy’s ability to certify a strike group (higher impact on mission effectiveness), or it could mean delaying a small in-port training event by 30 minutes to avoid exposure of a marine mammal to injurious levels of sound (lower impact). A responsible evaluation of ‘‘least practicable adverse impact’’ will consider the factors along these realistic scales. Accordingly, the greater the likelihood that a measure will contribute to reducing the probability or severity of adverse impacts to the species or stock or its habitat, the greater the weight that measure is given when considered in combination with practicability to determine the appropriateness of the mitigation measure, and vice versa. We discuss consideration of these factors in greater detail below. 1. Reduction of adverse impacts to marine mammal species or stocks and their habitat.6 The emphasis given to a measure’s ability to reduce the impacts on a species or stock considers the degree, likelihood, and context of the anticipated reduction of impacts to individuals (and how many individuals) as well as the status of the species or stock. The ultimate impact on any individual from a disturbance event (which informs the likelihood of adverse species- or stock-level effects) is dependent on the circumstances and associated contextual factors, such as duration of exposure to stressors. Though any proposed mitigation needs to be evaluated in the context of the specific activity and the species or stocks affected, measures with the following types of effects have greater value in reducing the likelihood or severity of adverse species- or stocklevel impacts: Avoiding or minimizing injury or mortality; limiting interruption of known feeding, breeding, mother/ young, or resting behaviors; minimizing the abandonment of important habitat (temporally and spatially); minimizing the number of individuals subjected to these types of disruptions; and limiting degradation of habitat. Mitigating these types of effects is intended to reduce the likelihood that the activity will result in energetic or other types of impacts that 6 We recognize the least practicable adverse impact standard requires consideration of measures that will address minimizing impacts on the availability of the species or stocks for subsistence uses where relevant. Because subsistence uses are not implicated for this action, we do not discuss them. However, a similar framework would apply for evaluating those measures, taking into account the MMPA’s directive that we make a finding of no unmitigable adverse impact on the availability of the species or stocks for taking for subsistence, and the relevant implementing regulations. E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 33990 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules are more likely to result in reduced reproductive success or survivorship. It is also important to consider the degree of impacts that are expected in the absence of mitigation in order to assess the added value of any potential measures. Finally, because the least practicable adverse impact standard gives NMFS discretion to weigh a variety of factors when determining appropriate mitigation measures and because the focus of the standard is on reducing impacts at the species or stock level, the least practicable adverse impact standard does not compel mitigation for every kind of take, or every individual taken, if that mitigation is unlikely to meaningfully contribute to the reduction of adverse impacts on the species or stock and its habitat, even when practicable for implementation by the applicant. The status of the species or stock is also relevant in evaluating the appropriateness of potential mitigation measures in the context of least practicable adverse impact. The following are examples of factors that may (either alone, or in combination) result in greater emphasis on the importance of a mitigation measure in reducing impacts on a species or stock: The stock is known to be decreasing or status is unknown, but believed to be declining; the known annual mortality (from any source) is approaching or exceeding the potential biological removal (PBR) level (as defined in MMPA section 3(20)); the affected species or stock is a small, resident population; or the stock is involved in a UME or has other known vulnerabilities, such as recovering from an oil spill. Habitat mitigation, particularly as it relates to rookeries, mating grounds, and areas of similar significance, is also relevant to achieving the standard and can include measures such as reducing impacts of the activity on known prey utilized in the activity area or reducing impacts on physical habitat. As with species- or stock-related mitigation, the emphasis given to a measure’s ability to reduce impacts on a species or stock’s habitat considers the degree, likelihood, and context of the anticipated reduction of impacts to habitat. Because habitat value is informed by marine mammal presence and use, in some cases there may be overlap in measures for the species or stock and for use of habitat. We consider available information indicating the likelihood of any measure to accomplish its objective. If evidence shows that a measure has not typically been effective nor successful, then either that measure should be modified VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 or the potential value of the measure to reduce effects should be lowered. 2. Practicability. Factors considered may include cost, impact on activities, and, in the case of a military readiness activity, will include personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity (see MMPA section 101(a)(5)(A)(ii)). Assessment of Mitigation Measures for NWTT Study Area NMFS has fully reviewed the specified activities and the mitigation measures included in the Navy’s rulemaking/LOA application and the 2019 NWTT DSEIS/OEIS to determine if the mitigation measures would result in the least practicable adverse impact on marine mammals and their habitat. NMFS worked with the Navy in the development of the Navy’s initially proposed measures, which are informed by years of implementation and monitoring. A complete discussion of the Navy’s evaluation process used to develop, assess, and select mitigation measures, which was informed by input from NMFS, can be found in Chapter 5 (Mitigation) and Appendix K (Geographic Mitigation Assessment) of the 2019 NWTT DSEIS/OEIS. The process described in Chapter 5 (Mitigation) and Appendix K (Geographic Mitigation Assessment) of the 2019 NWTT DSEIS/OEIS robustly supported NMFS’ independent evaluation of whether the mitigation measures would meet the least practicable adverse impact standard. The Navy would be required to implement the mitigation measures identified in this rule for the full seven years to avoid or reduce potential impacts from acoustic, explosive, and physical disturbance and strike stressors. As a general matter, where an applicant proposes measures that are likely to reduce impacts to marine mammals, the fact that they are included in the application indicates that the measures are practicable, and it is not necessary for NMFS to conduct a detailed analysis of the measures the applicant proposed (rather, they are simply included). However, it is still necessary for NMFS to consider whether there are additional practicable measures that would meaningfully reduce the probability or severity of impacts that could affect reproductive success or survivorship. Overall the Navy has agreed to procedural mitigation measures that would reduce the probability and/or severity of impacts expected to result from acute exposure to acoustic sources PO 00000 Frm 00078 Fmt 4701 Sfmt 4702 or explosives, ship strike, and impacts to marine mammal habitat. Specifically, the Navy would use a combination of delayed starts, powerdowns, and shutdowns to avoid mortality or serious injury, minimize the likelihood or severity of PTS or other injury, and reduce instances of TTS or more severe behavioral disruption caused by acoustic sources or explosives. The Navy would also implement multiple time/area restrictions that would reduce take of marine mammals in areas or at times where they are known to engage in important behaviors, such as calving, where the disruption of those behaviors would have a higher probability of resulting in impacts on reproduction or survival of individuals that could lead to population-level impacts. The Navy assessed the practicability of the proposed measures in the context of personnel safety, practicality of implementation, and their impacts on the Navy’s ability to meet their Title 10 requirements and found that the measures are supportable. As described in more detail below, NMFS has independently evaluated the measures the Navy proposed in the manner described earlier in this section (i.e., in consideration of their ability to reduce adverse impacts on marine mammal species and their habitat and their practicability for implementation). We have determined that the measures will significantly and adequately reduce impacts on the affected marine mammal species and stocks and their habitat and, further, be practicable for Navy implementation. Therefore, the mitigation measures assure that the Navy’s activities will have the least practicable adverse impact on the species or stocks and their habitat. The Navy also evaluated numerous measures in the 2019 NWTT DSEIS/ OEIS that were not included in the Navy’s rulemaking/LOA application, and NMFS independently reviewed and preliminarily concurs with the Navy’s analysis that their inclusion was not appropriate under the least practicable adverse impact standard based on our assessment. The Navy considered these additional potential mitigation measures in two groups. First, Chapter 5 (Mitigation) of the 2019 NWTT DSEIS/ OEIS, in the Measures Considered but Eliminated section, includes an analysis of an array of different types of mitigation that have been recommended over the years by non-governmental organizations or the public, through scoping or public comment on environmental compliance documents. Appendix K (Geographic Mitigation Assessment) of the 2019 NWTT DSEIS/ OEIS includes an in-depth analysis of E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 time/area restrictions that have been recommended over time or previously implemented as a result of litigation (outside of the NWTT Study Area). As described in Chapter 5 (Mitigation) of the 2019 NWTT DSEIS/OEIS, commenters sometimes recommend that the Navy reduce its overall amount of training, reduce explosive use, modify its sound sources, completely replace live training with computer simulation, or include time of day restrictions. Many of these mitigation measures could potentially reduce the number of marine mammals taken, via direct reduction of the activities or amount of sound energy put in the water. However, as described in Chapter 5 (Mitigation) of the 2019 NWTT DSEIS/ OEIS, the Navy needs to train and test in the conditions in which it fights— and these types of modifications fundamentally change the activity in a manner that would not support the purpose and need for the training and testing (i.e., are entirely impracticable) and therefore are not considered further. NMFS finds the Navy’s explanation for why adoption of these recommendations would unacceptably undermine the purpose of the testing and training persuasive. After independent review, NMFS finds Navy’s judgment on the impacts of potential mitigation measures to personnel safety, practicality of implementation, and the effectiveness of training and testing within the NWTT Study Area persuasive, and for these reasons, NMFS finds that these measures do not meet the least practicable adverse impact standard because they are not practicable. Second, in Chapter 5 (Mitigation) of the 2019 NWTT DSEIS/OEIS, the Navy evaluated additional potential procedural mitigation measures, including increased mitigation zones, ramp-up measures, additional passive acoustic and visual monitoring, and decreased vessel speeds. Some of these measures have the potential to incrementally reduce take to some degree in certain circumstances, though the degree to which this would occur is typically low or uncertain. However, as described in the Navy’s analysis, the measures would have significant direct negative effects on mission effectiveness and are considered impracticable (see Chapter 5 Mitigation of 2019 NWTT DSEIS/OEIS). NMFS independently reviewed the Navy’s evaluation and concurs with this assessment, which supports NMFS’ preliminary findings that the impracticability of this additional mitigation would greatly outweigh any potential minor reduction in marine mammal impacts that might result; therefore, these additional mitigation measures are not warranted. Last, Appendix K (Geographic Mitigation Assessment) of the 2019 NWTT DSEIS/OEIS describes a comprehensive method for analyzing potential geographic mitigation that includes consideration of both a biological assessment of how the potential time/area limitation would benefit the species and its habitat (e.g., is a key area of biological importance or would result in avoidance or reduction of impacts) in the context of the stressors of concern in the specific area and an operational assessment of the practicability of implementation (e.g., including an assessment of the specific importance of that area for training, considering proximity to training ranges and emergency landing fields and other issues). For most of the areas that were considered in the 2019 NWTT DSEIS/ OEIS but not included in this rule, the Navy found that the mitigation was not warranted because the anticipated reduction of adverse impacts on marine mammal species and their habitat was not sufficient to offset the impracticability of implementation. In some cases potential benefits to marine mammals were non-existent, while in others the consequences on mission effectiveness were too great. NMFS has reviewed the Navy’s analysis in Chapter 5 Mitigation and Appendix K Geographic Mitigation Assessment of the 2019 NWTT DSEIS/ OEIS, which considers the same factors that NMFS considers to satisfy the least practicable adverse impact standard, and concurs with the analysis and conclusions. Therefore, NMFS is not proposing to include any of the measures that the Navy ruled out in the 2019 NWTT DSEIS/OEIS. Below are the mitigation measures that NMFS 33991 determined will ensure the least practicable adverse impact on all affected species and their habitat, including the specific considerations for military readiness activities. The following sections describe the mitigation measures that would be implemented in association with the training and testing activities analyzed in this document. The mitigation measures are organized into two categories: Procedural mitigation and mitigation areas. Procedural Mitigation Procedural mitigation is mitigation that the Navy would implement whenever and wherever an applicable training or testing activity takes place within the NWTT Study Area. The Navy customizes procedural mitigation for each applicable activity category or stressor. Procedural mitigation generally involves: (1) The use of one or more trained Lookouts to diligently observe for specific biological resources (including marine mammals) within a mitigation zone, (2) requirements for Lookouts to immediately communicate sightings of specific biological resources to the appropriate watch station for information dissemination, and (3) requirements for the watch station to implement mitigation (e.g., halt an activity) until certain recommencement conditions have been met. The first procedural mitigation (Table 35) is designed to aid Lookouts and other applicable Navy personnel with their observation, environmental compliance, and reporting responsibilities. The remainder of the procedural mitigation measures (Tables 36 through 49) are organized by stressor type and activity category and include acoustic stressors (i.e., active sonar, weapons firing noise), explosive stressors (i.e., sonobuoys, torpedoes, medium-caliber and largecaliber projectiles, missiles, bombs, mine counter-measure and neutralization activities, mine neutralization involving Navy divers), and physical disturbance and strike stressors (i.e., vessel movement, towed in-water devices, small-, medium-, and large-caliber non-explosive practice munitions, non-explosive missiles, nonexplosive bombs and mine shapes). TABLE 35—PROCEDURAL MITIGATION FOR ENVIRONMENTAL AWARENESS AND EDUCATION Procedural mitigation description Stressor or Activity: • All training and testing activities, as applicable. Mitigation Requirements: • Appropriate personnel (including civilian personnel) involved in mitigation and training or testing activity reporting under the specified activities will complete one or more modules of the U.S. Navy Afloat Environmental Compliance Training Series, as identified in their career path training plan. Modules include: VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00079 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 33992 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 35—PROCEDURAL MITIGATION FOR ENVIRONMENTAL AWARENESS AND EDUCATION—Continued Procedural mitigation description —Introduction to the U.S. Navy Afloat Environmental Compliance Training Series. The introductory module provides information on environmental laws (e.g., ESA, MMPA) and the corresponding responsibilities that are relevant to Navy training and testing activities. The material explains why environmental compliance is important in supporting the Navy’s commitment to environmental stewardship. —Marine Species Awareness Training. All bridge watch personnel, Commanding Officers, Executive Officers, maritime patrol aircraft aircrews, anti-submarine warfare and mine warfare rotary-wing aircrews, Lookouts, and equivalent civilian personnel must successfully complete the Marine Species Awareness Training prior to standing watch or serving as a Lookout. The Marine Species Awareness Training provides information on sighting cues, visual observation tools and techniques, and sighting notification procedures. Navy biologists developed Marine Species Awareness Training to improve the effectiveness of visual observations for biological resources, focusing on marine mammals and sea turtles, and including floating vegetation, jellyfish aggregations, and flocks of seabirds. —U.S. Navy Protective Measures Assessment Protocol. This module provides the necessary instruction for accessing mitigation requirements during the event planning phase using the Protective Measures Assessment Protocol software tool. —U.S. Navy Sonar Positional Reporting System and Marine Mammal Incident Reporting. This module provides instruction on the procedures and activity reporting requirements for the Sonar Positional Reporting System and marine mammal incident reporting. Procedural Mitigation for Acoustic Stressors Procedural Mitigation for Active Sonar Mitigation measures for acoustic stressors are provided in Tables 36 and 37. Procedural mitigation for active sonar is described in Table 36 below. TABLE 36—PROCEDURAL MITIGATION FOR ACTIVE SONAR khammond on DSKJM1Z7X2PROD with PROPOSALS2 Procedural mitigation description Stressor or Activity: • Low-frequency active sonar, mid-frequency active sonar, high-frequency active sonar: —For vessel-based active sonar activities, mitigation applies only to sources that are positively controlled and deployed from manned surface vessels (e.g., sonar sources towed from manned surface platforms). —For aircraft-based active sonar activities, mitigation applies only to sources that are positively controlled and deployed from manned aircraft that do not operate at high altitudes (e.g., rotary-wing aircraft). Mitigation does not apply to active sonar sources deployed from unmanned aerial systems or aircraft operating at high altitudes (e.g., maritime patrol aircraft). Number of Lookouts and Observation Platform: • Hull-mounted sources: —1 Lookout: Platforms with space or manning restrictions while underway (at the forward part of a small boat or ship) and platforms using active sonar while moored or at anchor (including pierside). —2 Lookouts: Platforms without space or manning restrictions while underway (at the forward part of the ship). • Sources that are not hull-mounted: —1 Lookout on the ship or aircraft conducting the activity. Mitigation Requirements: • Mitigation zones: —1,000 yd power down, 500 yd power down, and 200 yd or 100 yd shut down for low-frequency active sonar ≥200 decibels (dB) and hull-mounted mid-frequency active sonar. —200 yd or 100 yd shut down for low-frequency active sonar <200 dB, mid-frequency active sonar sources that are not hull-mounted, and high-frequency active sonar. • Prior to the initial start of the activity (e.g., when maneuvering on station): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of active sonar transmission. • During the activity: —Low-frequency active sonar ≥200 decibels (dB) and hull-mounted mid-frequency active sonar: Observe the mitigation zone for marine mammals; power down active sonar transmission by 6 dB if a marine mammal is observed within 1,000 yd of the sonar source; power down an additional 4 dB (10 dB total) if a marine mammal is observed within 500 yd; cease transmission if a cetacean in the NWTT Offshore Area, NWTT Inland Area, or Western Behm Canal is observed within 200 yd; cease transmission if a pinniped in the NWTT Offshore Area or Western Behm Canal is observed within 200 yd and cease transmission if a pinniped in NWTT Inland Waters is observed within 100 yd (except if hauled out on, or in the water near, man-made structures and vessels). —Low-frequency active sonar <200 dB, mid-frequency active sonar sources that are not hull-mounted, and high-frequency active sonar: Observe the mitigation zone for marine mammals; cease transmission if a cetacean or pinniped in the NWTT Offshore Area or Western Behm Canal is observed within 200 yd of the sonar source; cease transmission if a pinniped in NWTT Inland Waters is observed within 100 yd (except if hauled out on, or in the water near, man-made structures and vessels). • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00080 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 33993 TABLE 36—PROCEDURAL MITIGATION FOR ACTIVE SONAR—Continued Procedural mitigation description —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing or powering up active sonar transmission) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the sonar source; (3) the mitigation zone has been clear from any additional sightings for 10 minutes for aircraft-deployed sonar sources or 30 minutes for vessel-deployed sonar sources; (4) for mobile activities, the active sonar source has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting; or (5) for activities using hull-mounted sonar, the Lookout concludes that dolphins are deliberately closing in on the ship to ride the ship’s bow wave, and are therefore out of the main transmission axis of the sonar (and there are no other marine mammal sightings within the mitigation zone). Procedural Mitigation for Weapons Firing Noise Procedural mitigation for weapons firing noise is described in Table 37 below. TABLE 37—PROCEDURAL MITIGATION FOR WEAPONS FIRING NOISE Procedural mitigation description Stressor or Activity: • Weapons firing noise associated with large-caliber gunnery activities. Number of Lookouts and Observation Platform: • 1 Lookout positioned on the ship conducting the firing; —Depending on the activity, the Lookout could be the same one described in Table 40 for Explosive Medium-Caliber and Large-Caliber Projectiles or Table 47 for Small-, Medium-, and Large-Caliber Non-Explosive Practice Munitions. Mitigation Requirements: • Mitigation zone: —30° on either side of the firing line out to 70 yd from the muzzle of the weapon being fired. • Prior to the initial start of the activity: —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of weapons firing. • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease weapons firing. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing weapons firing) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the firing ship; (3) the mitigation zone has been clear from any additional sightings for 30 minutes; or (4) for mobile activities, the firing ship has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. Procedural Mitigation for Explosive Stressors Procedural Mitigation for Explosive Sonobuoys Mitigation measures for explosive stressors are provided in Tables 38 through 44. Procedural mitigation for explosive sonobuoys is described in Table 38 below. TABLE 38—PROCEDURAL MITIGATION FOR EXPLOSIVE SONOBUOYS khammond on DSKJM1Z7X2PROD with PROPOSALS2 Procedural mitigation description Stressor or Activity: • Explosive sonobuoys. Number of Lookouts and Observation Platform: • 1 Lookout positioned in an aircraft or on a small boat. • If additional platforms are participating in the activity, personnel positioned in those assets (e.g., safety observers, evaluators) will support observing the mitigation zone for marine mammals while performing their regular duties. Mitigation Requirements: • Mitigation zone: —600 yd. around an explosive sonobuoy. • Prior to the initial start of the activity (e.g., during deployment of a sonobuoy field, which typically lasts 20–30 minutes): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Conduct passive acoustic monitoring for marine mammals; use information from detections to assist visual observations. —Visually observe the mitigation zone for marine mammals; if observed, relocate or delay the start of sonobuoy or source/receiver pair detonations. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00081 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 33994 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 38—PROCEDURAL MITIGATION FOR EXPLOSIVE SONOBUOYS—Continued Procedural mitigation description • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease sonobuoy or source/receiver pair detonations. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing detonations) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the sonobuoy; or (3) the mitigation zone has been clear from any additional sightings for 10 minutes when the activity involves aircraft that have fuel constraints, or 30 minutes when the activity involves aircraft that are not typically fuel constrained. • After completion of the activity (e.g., prior to maneuvering off station): —When practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, follow established incident reporting procedures. —If additional platforms are supporting this activity (e.g., providing range clearance), these assets will assist in the visual observation of the area where detonations occurred. Procedural Mitigation for Explosive Torpedoes Procedural mitigation for explosive torpedoes is described in Table 39 below. TABLE 39—PROCEDURAL MITIGATION FOR EXPLOSIVE TORPEDOES Procedural Mitigation Description khammond on DSKJM1Z7X2PROD with PROPOSALS2 Stressor or Activity: • Explosive torpedoes. Number of Lookouts and Observation Platform: • 1 Lookout positioned in an aircraft. • If additional platforms are participating in the activity, personnel positioned in those assets (e.g., safety observers, evaluators) will support observing the mitigation zone for marine mammals while performing their regular duties. Mitigation Requirements: • Mitigation zone: —2,100 yd around the intended impact location. • Prior to the initial start of the activity (e.g., during deployment of the target): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Conduct passive acoustic monitoring for marine mammals; use information from detections to assist visual observations. —Visually observe the mitigation zone for marine mammals; if observed, relocate or delay the start of firing. • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease firing. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; or (3) the mitigation zone has been clear from any additional sightings for 10 minutes when the activity involves aircraft that have fuel constraints, or 30 minutes when the activity involves aircraft that are not typically fuel constrained. • After completion of the activity (e.g., prior to maneuvering off station): —When practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, follow established incident reporting procedures. —If additional platforms are supporting this activity (e.g., providing range clearance), these assets will assist in the visual observation of the area where detonations occurred. Procedural Mitigation for Explosive Medium-Caliber and Large-Caliber Projectiles Projectiles is described in Table 40 below. Procedural mitigation for Explosive Medium-Caliber and Large-Caliber VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00082 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 33995 TABLE 40—PROCEDURAL MITIGATION FOR EXPLOSIVE MEDIUM-CALIBER AND LARGE-CALIBER PROJECTILES Procedural mitigation description Stressor or Activity: • Gunnery activities using explosive medium-caliber and large-caliber projectiles: —Mitigation applies to activities using a surface target. Number of Lookouts and Observation Platform: • 1 Lookout on the vessel conducting the activity: —For activities using explosive large-caliber projectiles, depending on the activity, the Lookout could be the same as the one described in Table 37 for Weapons Firing Noise. • If additional platforms are participating in the activity, personnel positioned in those assets (e.g., safety observers, evaluators) will support observing the mitigation zone for marine mammals while performing their regular duties. Mitigation Requirements: • Mitigation zones: —600 yd around the intended impact location for explosive medium-caliber projectiles. —1,000 yd around the intended impact location for explosive large-caliber projectiles. • Prior to the initial start of the activity (e.g., when maneuvering on station): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of firing. • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease firing. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; (3) the mitigation zone has been clear from any additional sightings for 30 minutes for vessel-based firing; or (4) for activities using mobile targets, the intended impact location has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. • After completion of the activity (e.g., prior to maneuvering off station): —When practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, follow established incident reporting procedures. —If additional platforms are supporting this activity (e.g., providing range clearance), these assets will assist in the visual observation of the area where detonations occurred. Procedural Mitigation for Explosive Missiles Procedural mitigation for explosive missiles is described in Table 41 below. TABLE 41—PROCEDURAL MITIGATION FOR EXPLOSIVE MISSILES khammond on DSKJM1Z7X2PROD with PROPOSALS2 Procedural mitigation description Stressor or Activity: • Aircraft-deployed explosive missiles: —Mitigation applies to activities using a surface target. Number of Lookouts and Observation Platform: • 1 Lookout positioned in an aircraft. • If additional platforms are participating in the activity, personnel positioned in those assets (e.g., safety observers, evaluators) will support observing the mitigation zone for marine mammals while performing their regular duties. Mitigation Requirements: • Mitigation zone: —2,000 yd around the intended impact location. • Prior to the initial start of the activity (e.g., during a fly-over of the mitigation zone): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of firing. • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease firing. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; or (3) the mitigation zone has been clear from any additional sightings for 10 minutes when the activity involves aircraft that have fuel constraints, or 30 minutes when the activity involves aircraft that are not typically fuel constrained. • After completion of the activity (e.g., prior to maneuvering off station): —When practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, follow established incident reporting procedures. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00083 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 33996 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 41—PROCEDURAL MITIGATION FOR EXPLOSIVE MISSILES—Continued Procedural mitigation description —If additional platforms are supporting this activity (e.g., providing range clearance), these assets will assist in the visual observation of the area where detonations occurred. Procedural Mitigation for Explosive Bombs Procedural mitigation for explosive bombs is described in Table 42 below. TABLE 42—PROCEDURAL MITIGATION FOR EXPLOSIVE BOMBS Procedural mitigation description Stressor or Activity: • Explosive bombs. Number of Lookouts and Observation Platform: • 1 Lookout positioned in the aircraft conducting the activity. • If additional platforms are participating in the activity, personnel positioned in those assets (e.g., safety observers, evaluators) will support observing the mitigation zone for marine mammals while performing their regular duties. Mitigation Requirements: • Mitigation zone: —2,500 yd around the intended target. • Prior to the initial start of the activity (e.g., when arriving on station): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of bomb deployment. • During the activity (e.g., during target approach): —Observe the mitigation zone for marine mammals; if observed, cease bomb deployment. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing bomb deployment) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended target; (3) the mitigation zone has been clear from any additional sightings for 10 minutes; or (4) for activities using mobile targets, the intended target has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. • After completion of the activity (e.g., prior to maneuvering off station): —When practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, follow established incident reporting procedures. —If additional platforms are supporting this activity (e.g., providing range clearance), these assets will assist in the visual observation of the area where detonations occurred. Procedural Mitigation for Explosive Mine Countermeasure and Neutralization Activities activities is described in Table 43 below. Procedural mitigation for explosive mine countermeasure and neutralization TABLE 43—PROCEDURAL MITIGATION FOR EXPLOSIVE MINE COUNTERMEASURE AND NEUTRALIZATION ACTIVITIES khammond on DSKJM1Z7X2PROD with PROPOSALS2 Procedural mitigation description Stressor or Activity: • Explosive mine countermeasure and neutralization activities. Number of Lookouts and Observation Platform: • 1 Lookout positioned on a vessel or in an aircraft when implementing the smaller mitigation zone. • 2 Lookouts (one positioned in an aircraft and one on a small boat) when implementing the larger mitigation zone. • If additional platforms are participating in the activity, personnel positioned in those assets (e.g., safety observers, evaluators) will support observing the mitigation zone for marine mammals while performing their regular duties. Mitigation Requirements: • Mitigation zones: —600 yd around the detonation site for activities using ≤5 lb net explosive weight. —2,100 yd around the detonation site for activities using >5–60 lb net explosive weight. • Prior to the initial start of the activity (e.g., when maneuvering on station; typically, 10 minutes when the activity involves aircraft that have fuel constraints, or 30 minutes when the activity involves aircraft that are not typically fuel constrained): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of detonations. • During the activity: VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00084 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 33997 TABLE 43—PROCEDURAL MITIGATION FOR EXPLOSIVE MINE COUNTERMEASURE AND NEUTRALIZATION ACTIVITIES— Continued Procedural mitigation description —Observe for marine mammals; if observed, cease detonations. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing detonations) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to detonation site; or (3) the mitigation zone has been clear from any additional sightings for 10 minutes when the activity involves aircraft that have fuel constraints, or 30 minutes when the activity involves aircraft that are not typically fuel constrained. • After completion of the activity (typically 10 minutes when the activity involves aircraft that have fuel constraints, or 30 minutes when the activity involves aircraft that are not typically fuel constrained): —Observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, follow established incident reporting procedures. —If additional platforms are supporting this activity (e.g., providing range clearance), these assets will assist in the visual observation of the area where detonations occurred. Procedural Mitigation for Explosive Mine Neutralization Activities lnvolving Navy Divers Navy divers is described in Table 44 below. Procedural mitigation for explosive mine neutralization activities involving TABLE 44—PROCEDURAL MITIGATION FOR EXPLOSIVE MINE NEUTRALIZATION ACTIVITIES INVOLVING NAVY DIVERS khammond on DSKJM1Z7X2PROD with PROPOSALS2 Procedural mitigation description Stressor or Activity: • Explosive mine neutralization activities involving Navy divers. Number of Lookouts and Observation Platform: • 2 Lookouts on two small boats with one Lookout each, one of which will be a Navy biologist. • All divers placing the charges on mines will support the Lookouts while performing their regular duties and will report applicable sightings to the lead Lookout, the supporting small boat, or the Range Safety Officer. • If additional platforms are participating in the activity, personnel positioned in those assets (e.g., safety observers, evaluators) will support observing the mitigation zone for marine mammals while performing their regular duties. Mitigation Requirements: • Mitigation zone: —500 yd around the detonation site during activities using >0.5–2.5 lb net explosive weight. • Prior to the initial start of the activity (starting 30 minutes before the first planned detonation): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of detonations. —The Navy will ensure the area is clear of marine mammals for 30 minutes prior to commencing a detonation. —A Navy biologist will serve as the lead Lookout and will make the final determination that the mitigation zone is clear of any biological resource sightings prior to the commencement of a detonation. The Navy biologist will maintain radio communication with the unit conducting the event and the other Lookout. • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease detonations. —To the maximum extent practicable depending on mission requirements, safety, and environmental conditions, boats will position themselves near the midpoint of the mitigation zone radius (but outside of the detonation plume and human safety zone), will position themselves on opposite sides of the detonation location, and will travel in a circular pattern around the detonation location with one Lookout observing inward toward the detonation site and the other observing outward toward the perimeter of the mitigation zone. —The Navy will use only positively controlled charges (i.e., no time-delay fuses). —The Navy will use the smallest practicable charge size for each activity. —Activities will be conducted in Beaufort sea state number 2 conditions or better and will not be conducted in low visibility conditions. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing detonations) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the detonation site; or (3) the mitigation zone has been clear from any additional sightings for 30 minutes. • After each detonation and the completion of an activity (for 30 minutes): —Observe for marine mammals in the vicinity of where detonations occurred and immediately downstream of the detonation location; if any injured or dead marine mammals are observed, follow established incident reporting procedures. —If additional platforms are supporting this activity (e.g., providing range clearance), these assets will assist in the visual observation of the area where detonations occurred. • Additional requirements: —At the Hood Canal Explosive Ordnance Disposal Range and Crescent Harbor Explosive Ordnance Disposal Range, naval units will obtain permission from the appropriate designated Command authority prior to conducting explosive mine neutralization activities involving the use of Navy divers. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00085 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 33998 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 44—PROCEDURAL MITIGATION FOR EXPLOSIVE MINE NEUTRALIZATION ACTIVITIES INVOLVING NAVY DIVERS— Continued Procedural mitigation description —At the Hood Canal Explosive Ordnance Disposal Range, during February, March, and April (the juvenile migration period for Hood Canal Summer Run Chum), the Navy will not use explosives in bin E3 (>0.5–2.5 lb net explosive weight), and will instead use explosives in bin E0 (<0.1 lb net explosive weight). —At the Hood Canal Explosive Ordnance Disposal Range, during August, September, and October (the adult migration period for Hood Canal summer-run chum and Puget Sound Chinook), the Navy will avoid the use of explosives in bin E3 (>0.5–2.5 lb net explosive weight), and will instead use explosive bin E0 (<0.1 lb net explosive weight) to the maximum extent practicable unless necessitated by mission requirements. —At the Crescent Harbor Explosive Ordnance Disposal Range, the Navy will conduct explosive activities at least 1,000 m from the closest point of land to avoid or reduce impacts on fish (e.g., bull trout) in nearshore habitat areas. Procedural Mitigation for Physical Disturbance and Strike Stressors Procedural Mitigation for Vessel Movement Mitigation measures for physical disturbance and strike stressors are provided in Tables 45 through 49. Procedural mitigation for vessel movement is described in Table 45 below. TABLE 45—PROCEDURAL MITIGATION FOR VESSEL MOVEMENT Procedural mitigation description Stressor or Activity: • Vessel movement: —The mitigation will not be applied if: (1) The vessel’s safety is threatened, (2) the vessel is restricted in its ability to maneuver (e.g., during launching and recovery of aircraft or landing craft, during towing activities, when mooring, during Transit Protection Program exercises or other events involving escort vessels), (3) the vessel is operated autonomously, or (4) when impractical based on mission requirements (e.g., during test body retrieval by range craft). Number of Lookouts and Observation Platform: • 1 Lookout on the vessel that is underway. Mitigation Requirements: • Mitigation zones: —500 yd (for surface ships other than small boats) around whales. —200 yd (for surface ships other than small boats) around all marine mammals other than whales (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels). —100 yd (for small boats, such as range craft) around marine mammals (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels). • During the activity: —When underway, observe the mitigation zone for marine mammals; if observed, maneuver to maintain distance. • Additional requirements: —Prior to Small Boat Attack exercises at Naval Station Everett, Naval Base Kitsap Bangor, or Naval Base Kitsap Bremerton, Navy event planners will coordinate with Navy biologists during the event planning process. Navy biologists will work with NMFS to determine the likelihood of marine mammal presence in the planned training location. Navy biologists will notify event planners of the likelihood of species presence as they plan specific details of the event (e.g., timing, location, duration). The Navy will provide additional environmental awareness training to event participants. The training will alert participating ship and aircraft crews to the possible presence of marine mammals in the training location. Lookouts will use the information to assist their visual observation of applicable mitigation zones and to aid in the implementation of procedural mitigation. —If a marine mammal vessel strike occurs, the Navy will follow the established incident reporting procedures. Procedural Mitigation for Towed InWater Devices TABLE 46—PROCEDURAL MITIGATION FOR TOWED IN-WATER DEVICES khammond on DSKJM1Z7X2PROD with PROPOSALS2 Procedural mitigation description Stressor or Activity: • Towed in-water devices: —Mitigation applies to devices towed from a manned surface platform or manned aircraft, or when a manned support craft is already participating in an activity involving in-water devices being towed by unmanned platforms. —The mitigation will not be applied if the safety of the towing platform or in-water device is threatened. Number of Lookouts and Observation Platform: • 1 Lookout positioned on the towing platform or support craft. Mitigation Requirements: • Mitigation zones: —250 yd (for in-water devices towed by aircraft or surface ships other than small boats) around marine mammals (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels). VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00086 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 33999 TABLE 46—PROCEDURAL MITIGATION FOR TOWED IN-WATER DEVICES—Continued Procedural mitigation description —100 yd (for in-water devices towed by small boats, such as range craft) around marine mammals (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels). • During the activity (i.e., when towing an in-water device): —Observe the mitigation zone for marine mammals; if observed, maneuver to maintain distance. Procedural Mitigation for Small-, Medium-, and Large-Caliber NonExplosive Practice Munitions TABLE 47—PROCEDURAL MITIGATION FOR SMALL-, MEDIUM-, AND LARGE-CALIBER NON-EXPLOSIVE PRACTICE MUNITIONS Procedural mitigation description Stressor or Activity: • Gunnery activities using small-, medium-, and large-caliber non-explosive practice munitions: —Mitigation applies to activities using a surface target. Number of Lookouts and Observation Platform: • 1 Lookout positioned on the platform conducting the activity. • Depending on the activity, the Lookout could be the same as the one described in Table 37 for Weapons Firing Noise. Mitigation Requirements: • Mitigation zone: —200 yd around the intended impact location. • Prior to the initial start of the activity (e.g., when maneuvering on station): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of firing. • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease firing. • Commencement/recommencement conditions after a marine mammal sighting before or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; (3) the mitigation zone has been clear from any additional sightings for 10 minutes for aircraft-based firing or 30 minutes for vessel-based firing; or (4) for activities using a mobile target, the intended impact location has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. Procedural Mitigation for Non-Explosive Missiles TABLE 48—PROCEDURAL MITIGATION FOR NON-EXPLOSIVE MISSILES khammond on DSKJM1Z7X2PROD with PROPOSALS2 Procedural mitigation description Stressor or Activity: • Aircraft-deployed non-explosive missiles: —Mitigation applies to activities using a surface target. Number of Lookouts and Observation Platform: • 1 Lookout positioned in an aircraft. Mitigation Requirements: • Mitigation zone: —900 yd around the intended impact location. • Prior to the initial start of the activity (e.g., during a fly-over of the mitigation zone): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of firing. • During the activity: —Observe the mitigation zone for marine mammals; if observed, cease firing. • Commencement/recommencement conditions after a marine mammal sighting prior to or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; or (3) the mitigation zone has been clear from any additional sightings for 10 minutes when the activity involves aircraft that have fuel constraints, or 30 minutes when the activity involves aircraft that are not typically fuel constrained. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00087 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 34000 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Procedural Mitigation for Non-Explosive Bombs and Mine Shapes TABLE 49—PROCEDURAL MITIGATION FOR NON-EXPLOSIVE BOMBS AND MINE SHAPES Procedural mitigation description Stressor or Activity: • Non-explosive bombs. • Non-explosive mine shapes during mine laying activities. Number of Lookouts and Observation Platform: • 1 Lookout positioned in an aircraft. Mitigation Requirements: • Mitigation zone: —1,000 yd around the intended target. • Prior to the initial start of the activity (e.g., when arriving on station): —Observe the mitigation zone for floating vegetation; if observed, relocate or delay the start until the mitigation zone is clear. —Observe the mitigation zone for marine mammals; if observed, relocate or delay the start of bomb deployment or mine laying. • During the activity (e.g., during approach of the target or intended minefield location): —Observe the mitigation zone for marine mammals; if observed, cease bomb deployment or mine laying. • Commencement/recommencement conditions after a marine mammal sighting prior to or during the activity: —The Navy will allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing bomb deployment or mine laying) until one of the following conditions has been met: (1) The animal is observed exiting the mitigation zone; (2) the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended target or minefield location; (3) the mitigation zone has been clear from any additional sightings for 10 minutes; or (4) for activities using mobile targets, the intended target has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. Mitigation Areas In addition to procedural mitigation, the Navy would implement mitigation measures within mitigation areas to avoid or minimize potential impacts on marine mammals. A full technical analysis (for which the methods were summarized above) of the mitigation areas that the Navy considered for marine mammals is provided in Appendix K (Geographic Mitigation Assessment) of the 2019 NWTT DSEIS/ OEIS. The Navy took into account public comments received on the 2019 NWTT DSEIS/OEIS, the best available science, and the practicability of implementing additional mitigation measures and has enhanced its mitigation areas and mitigation measures beyond those that were included in the 2015–2020 regulations to further reduce impacts to marine mammals. Information on the mitigation measures that the Navy will implement within mitigation areas is provided in Table 50 (see below). The mitigation applies year-round unless specified otherwise in the table. NMFS conducted an independent analysis of the mitigation areas that the Navy proposed, which are described below. NMFS preliminarily concurs with the Navy’s analysis, which indicates that the measures in these mitigation areas are both practicable and will reduce the likelihood or severity of adverse impacts to marine mammal species or their habitat in the manner described in the Navy’s analysis and this rule. NMFS is heavily reliant on the Navy’s description of operational practicability, since the Navy is best equipped to describe the degree to which a given mitigation measure affects personnel safety or mission effectiveness, and is practical to implement. The Navy considers the measures in this proposed rule to be practicable, and NMFS concurs. We further discuss the manner in which the Geographic Mitigation Areas in the proposed rule will reduce the likelihood or severity of adverse impacts to marine mammal species or their habitat in the Preliminary Analysis and Negligible Impact Determination section. TABLE 50—GEOGRAPHIC MITIGATION AREAS FOR MARINE MAMMALS IN THE NWTT STUDY AREA khammond on DSKJM1Z7X2PROD with PROPOSALS2 Mitigation area description Stressor or Activity: • Sonar. • Explosives. • Physical disturbance and strikes. Mitigation Requirements: • Marine Species Coastal Mitigation Area (year-round): —Within 50 nmi from shore in the Marine Species Coastal Mitigation Area, the Navy will not conduct: (1) Explosive training activities, (2) explosive testing activities (with the exception of explosive Mine Countermeasure and Neutralization Testing activities), and (3) non-explosive missile training activities. Should national security present a requirement to conduct these activities in the mitigation area, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. —Within 20 nmi from shore in the Marine Species Coastal Mitigation Area, the Navy will not conduct non-explosive large-caliber gunnery training activities and non-explosive bombing training activities. Should national security present a requirement to conduct these activities in the mitigation area, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00088 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 34001 TABLE 50—GEOGRAPHIC MITIGATION AREAS FOR MARINE MAMMALS IN THE NWTT STUDY AREA—Continued Mitigation area description • • • • • —Within 12 nmi from shore in the Marine Species Coastal Mitigation Area, the Navy will not conduct: (1) Non-explosive small- and medium-caliber gunnery training activities, (2) non-explosive torpedo training activities, and (3) Anti-Submarine Warfare Tracking Exercise—Helicopter, Maritime Patrol Aircraft, Ship, or Submarine training activities. Should national security present a requirement to conduct these activities in the mitigation area, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. Olympic Coast National Marine Sanctuary Mitigation Area (year-round): —Within the Olympic Coast National Marine Sanctuary Mitigation Area, the Navy will not conduct more than 32 hours of MF1 mid-frequency active sonar during training annually and will not conduct non-explosive bombing training activities. Should national security present a requirement to conduct more than 32 hours of MF1 mid-frequency active sonar during training annually or conduct non-explosive bombing training activities in the mitigation area, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. —Within the Olympic Coast National Marine Sanctuary Mitigation Area, the Navy will not conduct more than 33 hours of MF1 mid-frequency active sonar during testing annually (except within the portion of the mitigation area that overlaps the Quinault Range Site) and will not conduct explosive Mine Countermeasure and Neutralization Testing activities. Should national security present a requirement for the Navy to conduct more than 33 hours of MF1 mid-frequency active sonar during testing annually (except within the portion of the mitigation area that overlaps the Quinault Range Site) or conduct explosive Mine Countermeasure and Neutralization Testing activities in the mitigation area, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. Stonewall and Heceta Bank Humpback Whale Mitigation Area (May 1–November 30): —Within the Stonewall and Heceta Bank Humpback Whale Mitigation Area, the Navy will not use MF1 mid-frequency active sonar or explosives during training and testing from May 1 to November 30. Should national security present a requirement to use MF1 midfrequency active sonar or explosives during training and testing from May 1 to November 30, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. Point St. George Humpback Whale Mitigation Area (July 1–November 30): —Within the Point St. George Humpback Whale Mitigation Area, the Navy will not use MF1 mid-frequency active sonar or explosives during training and testing from July 1 to November 30. Should national security present a requirement to use MF1 mid-frequency active sonar or explosives during training and testing from July 1 to November 30, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. Puget Sound and Strait of Juan de Fuca Mitigation Area (year-round): —Within the Puget Sound and Strait of Juan de Fuca Mitigation Area, the Navy will require units to obtain approval from the appropriate designated Command authority prior to: (1) The use of hull-mounted mid-frequency active sonar during training while underway, and (2) conducting ship and submarine active sonar pierside maintenance or testing. —Within the Puget Sound and Strait of Juan de Fuca Mitigation Area for Civilian Port Defense—Homeland Security Anti-Terrorism/ Force Protection Exercises, Navy event planners will coordinate with Navy biologists during the event planning process. Navy biologists will work with NMFS to determine the likelihood of gray whale and Southern Resident Killer Whale presence in the planned training location. Navy biologists will notify event planners of the likelihood of species presence as they plan specific details of the event (e.g., timing, location, duration). The Navy will ensure environmental awareness of event participants. Environmental awareness will help alert participating ship and aircraft crews to the possible presence of marine mammals in the training location, such as gray whales and Southern Resident Killer Whales. Northern Puget Sound Gray Whale Mitigation Area (March 1–May 31): —Within the Northern Puget Sound Gray Whale Mitigation Area, the Navy will not conduct Civilian Port Defense—Homeland Security Anti-Terrorism/Force Protection Exercises from March 1 to May 31. Should national security present a requirement to conduct Civilian Port Defense—Homeland Security Anti-Terrorism/Force Protection Exercises from March 1 to May 31, naval units will obtain permission from the appropriate designated Command authority prior to commencement of the activity. The Navy will provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. khammond on DSKJM1Z7X2PROD with PROPOSALS2 BILLING CODE 3510–22–P VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00089 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules BILLING CODE 3510–22–C VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00090 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.007</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 34002 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Mitigation Conclusions NMFS has carefully evaluated the Navy’s proposed mitigation measures— many of which were developed with NMFS’ input during the previous phases of Navy training and testing authorizations but several of which are new since implementation of the current 2015 to 2020 regulations—and considered a broad range of other measures (i.e., the measures considered but eliminated in the 2019 NWTT DSEIS/OEIS, which reflect many of the comments that have arisen via NMFS or public input in past years) in the context of ensuring that NMFS prescribes the means of effecting the least practicable adverse impact on the affected marine mammal species and their habitat. Our evaluation of potential measures included consideration of the following factors in relation to one another: The manner in which, and the degree to which, the successful implementation of the mitigation measures is expected to reduce the likelihood and/or magnitude of adverse impacts to marine mammal species and their habitat; the proven or likely efficacy of the measures; and the practicability of the measures for applicant implementation, including consideration of personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. Based on our evaluation of the Navy’s proposed measures, as well as other measures considered by the Navy and NMFS, NMFS has preliminarily determined that these proposed mitigation measures are appropriate means of effecting the least practicable adverse impact on marine mammal species and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and considering specifically personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. Additionally, an adaptive management component helps further ensure that mitigation is regularly assessed and provides a mechanism to improve the mitigation, based on the factors above, through modification as appropriate. The proposed rule comment period provides the public an opportunity to submit recommendations, views, and/or concerns regarding the Navy’s activities and the proposed mitigation measures. While NMFS has preliminarily determined that the Navy’s proposed mitigation measures would effect the least practicable adverse impact on the affected species and their habitat, NMFS VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 will consider all public comments to help inform our final determination. Consequently, the proposed mitigation measures may be refined, modified, removed, or added to prior to the issuance of the final rule based on public comments received and, as appropriate, analysis of additional potential mitigation measures. Proposed Monitoring Section 101(a)(5)(A) of the MMPA states that in order to authorize incidental take for an activity, NMFS must set forth requirements pertaining to the monitoring and reporting of such taking. The MMPA implementing regulations at 50 CFR 216.104(a)(13) indicate that requests for incidental take authorizations must include the suggested means of accomplishing the necessary monitoring and reporting that will result in increased knowledge of the species and of the level of taking or impacts on populations of marine mammals that are expected to be present. Although the Navy has been conducting research and monitoring in the NWTT Study Area for over 20 years, it developed a formal marine species monitoring program in support of the MMPA and ESA authorizations in 2009. This robust program has resulted in hundreds of technical reports and publications on marine mammals that have informed Navy and NMFS analyses in environmental planning documents, rules, and Biological Opinions. The reports are made available to the public on the Navy’s marine species monitoring website (www.navymarinespeciesmonitoring.us) and the data on the Ocean Biogeographic Information System Spatial Ecological Analysis of Megavertebrate Populations (OBIS–SEAMAP) (https:// seamap.env.duke.edu/). The Navy will continue collecting monitoring data to inform our understanding of the occurrence of marine mammals in the NWTT Study Area; the likely exposure of marine mammals to stressors of concern in the NWTT Study Area; the response of marine mammals to exposures to stressors; the consequences of a particular marine mammal response to their individual fitness and, ultimately, populations; and the effectiveness of implemented mitigation measures. Taken together, mitigation and monitoring comprise the Navy’s integrated approach for reducing environmental impacts from the specified activities. The Navy’s overall monitoring approach seeks to leverage PO 00000 Frm 00091 Fmt 4701 Sfmt 4702 34003 and build on existing research efforts whenever possible. As agreed upon between the Navy and NMFS, the monitoring measures presented here, as well as the mitigation measures described above, focus on the protection and management of potentially affected marine mammals. A well-designed monitoring program can provide important feedback for validating assumptions made in analyses and allow for adaptive management of marine resources. Monitoring is required under the MMPA, and details of the monitoring program for the specified activities have been developed through coordination between NMFS and the Navy through the regulatory process for previous Navy at-sea training and testing activities. Integrated Comprehensive Monitoring Program The Navy’s Integrated Comprehensive Monitoring Program (ICMP) is intended to coordinate marine species monitoring efforts across all regions and to allocate the most appropriate level and type of effort for each range complex based on a set of standardized objectives, and in acknowledgement of regional expertise and resource availability. The ICMP is designed to be flexible, scalable, and adaptable through the adaptive management and strategic planning processes to periodically assess progress and reevaluate objectives. This process includes conducting an annual adaptive management review meeting, at which the Navy and NMFS jointly consider the prior-year goals, monitoring results, and related scientific advances to determine if monitoring plan modifications are warranted to more effectively address program goals. Although the ICMP does not specify actual monitoring field work or individual projects, it does establish a matrix of goals and objectives that have been developed in coordination with NMFS. As the ICMP is implemented through the Strategic Planning Process, detailed and specific studies will be developed which support the Navy’s and NMFS top-level monitoring goals. In essence, the ICMP directs that monitoring activities relating to the effects of Navy training and testing activities on marine species should be designed to contribute towards or accomplish one or more of the following top-level goals: • An increase in the understanding of the likely occurrence of marine mammals and ESA-listed marine species in the vicinity of the action (i.e., presence, abundance, distribution, and density of species); • An increase in the understanding of the nature, scope, or context of the E:\FR\FM\02JNP2.SGM 02JNP2 34004 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 likely exposure of marine mammals and ESA-listed species to any of the potential stressors associated with the action (e.g., sound, explosive detonation, or expended materials), through better understanding of one or more of the following: (1) The nature of the action and its surrounding environment (e.g., sound-source characterization, propagation, and ambient noise levels), (2) the affected species (e.g., life history or dive patterns), (3) the likely co-occurrence of marine mammals and ESA-listed marine species with the action (in whole or part), and (4) the likely biological or behavioral context of exposure to the stressor for the marine mammal and ESA-listed marine species (e.g., age class of exposed animals or known pupping, calving, or feeding areas); • An increase in the understanding of how individual marine mammals or ESA-listed marine species respond (behaviorally or physiologically) to the specific stressors associated with the action (in specific contexts, where possible, e.g., at what distance or received level); • An increase in the understanding of how anticipated individual responses, to individual stressors or anticipated combinations of stressors, may impact either (1) the long-term fitness and survival of an individual; or (2) the population, species, or stock (e.g., through impacts on annual rates of recruitment or survival); • An increase in the understanding of the effectiveness of mitigation and monitoring measures; • A better understanding and record of the manner in which the Navy complies with the incidental take regulations and LOAs and the ESA Incidental Take Statement; • An increase in the probability of detecting marine mammals (through improved technology or methods), both specifically within the mitigation zone (thus allowing for more effective implementation of the mitigation) and in general, to better achieve the above goals; and • Ensuring that adverse impact of activities remains at the least practicable level. Strategic Planning Process for Marine Species Monitoring The Navy also developed the Strategic Planning Process for Marine Species Monitoring, which serves to guide the investment of resources to most efficiently address ICMP objectives and intermediate scientific objectives developed through this process. The Strategic Planning Process establishes the guidelines and processes necessary VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 to develop, evaluate, and fund individual projects based on objective scientific study questions. The process uses an underlying framework designed around intermediate scientific objectives and a conceptual framework incorporating a progression of knowledge spanning occurrence, exposure, response, and consequence. The Strategic Planning Process for Marine Species Monitoring is used to set overarching intermediate scientific objectives; develop individual monitoring project concepts; evaluate, prioritize, and select specific monitoring projects to fund or continue supporting for a given fiscal year; execute and manage selected monitoring projects; and report and evaluate progress and results. This process addresses relative investments to different range complexes based on goals across all range complexes, and monitoring would leverage multiple techniques for data acquisition and analysis whenever possible. More information on the Strategic Planning Process for Marine Species Monitoring including results, reports, and publications, is also available online (https://www. navymarinespeciesmonitoring.us/). Past and Current Monitoring in the NWTT Study Area The monitoring program has undergone significant changes since the first rule was issued for the NWTT Study Area in 2010, which highlights the monitoring program’s evolution through the process of adaptive management. The monitoring program developed for the first cycle of environmental compliance documents (e.g., U.S. Department of the Navy, 2008a, 2008b) utilized effort-based compliance metrics that were somewhat limiting. Through adaptive management discussions, the Navy designed and conducted monitoring studies according to scientific objectives and eliminated specific effort requirements. Progress has also been made on the conceptual framework categories from the Scientific Advisory Group for Navy Marine Species Monitoring (U.S. Department of the Navy, 2011), ranging from occurrence of animals, to their exposure, response, and population consequences. The Navy continues to manage the Atlantic and Pacific program as a whole, with monitoring in each range complex taking a slightly different but complementary approach. The Navy has continued to use the approach of layering multiple simultaneous components in many of the range complexes to leverage an increase in return of the progress toward answering scientific monitoring PO 00000 Frm 00092 Fmt 4701 Sfmt 4702 questions. This includes in the NWTT Study Area, for example, (a) satellite tagging of blue whales, fin whales, humpback whales, and Southern Resident killer whales; (b) analysis of existing passive acoustic monitoring datasets; and (c) line-transect aerial surveys for marine mammals in Puget Sound, Washington. Numerous publications, dissertations, and conference presentations have resulted from research conducted under the marine species monitoring program (https:// www.navymarinespeciesmonitoring.us/ reading-room/publications/), leading to a significant contribution to the body of marine mammal science. Publications on occurrence, distribution, and density have fed the modeling input, and publications on exposure and response have informed Navy and NMFS analysis of behavioral response and consideration of mitigation measures. Furthermore, collaboration between the monitoring program and the Navy’s research and development (e.g., the Office of Naval Research) and demonstration-validation (e.g., Living Marine Resources) programs has been strengthened, leading to research tools and products that have already transitioned to the monitoring program. These include Marine Mammal Monitoring on Ranges, controlled exposure experiment behavioral response studies, acoustic sea glider surveys, and global positioning systemenabled satellite tags. Recent progress has been made with better integration with monitoring across all Navy at-sea study areas, including the Atlantic Fleet Training and Testing Study Area in the Atlantic Ocean, and various other ranges. Publications from the Living Marine Resources and Office of Naval Research programs have also resulted in significant contributions to hearing, acoustic criteria used in effects modeling, exposure, and response, as well as in developing tools to assess biological significance (e.g., consequences). NMFS and the Navy also consider data collected during procedural mitigations as monitoring. Data are collected by shipboard personnel on hours spent training, hours of observation, hours of sonar, and marine mammals observed within the mitigation zones when mitigations are implemented. These data are provided to NMFS in both classified and unclassified annual exercise reports, which would continue under this proposed rule. NMFS has received multiple years’ worth of annual exercise and monitoring reports addressing active E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules sonar use and explosive detonations within the NWTT Study Area and other Navy range complexes. The data and information contained in these reports have been considered in developing mitigation and monitoring measures for the proposed training and testing activities within the NWTT Study Area. The Navy’s annual exercise and monitoring reports may be viewed at: https://www.fisheries.noaa.gov/ national/marine-mammal-protection/ incidental-take-authorizations-militaryreadiness-activities and https:// www.navymarinespeciesmonitoring.us/ reporting/. The Navy’s marine species monitoring program typically supports several monitoring projects in the NWTT Study Area at any given time. Additional details on the scientific objectives for each project can be found at https:// www.navymarinespeciesmonitoring.us/ regions/pacific/current-projects/. Projects can be either major multi-year efforts, or one to two-year special studies. The emphasis on monitoring in the Pacific Northwest is directed towards collecting and analyzing tagging data related to the occurrence of blue whales, fin whales, humpback whales, and Southern Resident killer whales. In 2017, researchers deployed 28 tags on blue whales and one tag on a fin whale off southern and central California (Mate et al., 2017). Detailed analyses for the 2017 tagging effort are ongoing and will be available later in a final report and posted at https:// www.navymarinespeciesmonitoring.us/. Humpback whales have been tagged with satellite tags, and biopsy samples have been collected (Mate et al., 2017). Location information on Southern Resident killer whales was provided via satellite tag data and acoustic detections (Hanson et al., 2018). Also, distribution of Chinook salmon (a key prey species of Southern Resident killer whales) in coastal waters from Alaska to Northern California was studied (Shelton et al., in review). Future monitoring efforts in the NWTT Study Area are anticipated to continue along the same objectives: Determining the species and populations of marine mammals present and potentially exposed to Navy training and testing activities in the NWTT Study Area, through tagging, passive acoustic monitoring, refined modeling, photo identification, biopsies, and visual monitoring. Adaptive Management The proposed regulations governing the take of marine mammals incidental to Navy training and testing activities in the NWTT Study Area contain an adaptive management component. Our VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 understanding of the effects of Navy training and testing activities (e.g., acoustic and explosive stressors) on marine mammals continues to evolve, which makes the inclusion of an adaptive management component both valuable and necessary within the context of seven-year regulations. The reporting requirements associated with this rule are designed to provide NMFS with monitoring data from the previous year to allow NMFS to consider whether any changes to existing mitigation and monitoring requirements are appropriate. The use of adaptive management allows NMFS to consider new information from different sources to determine (with input from the Navy regarding practicability) on an annual or biennial basis if mitigation or monitoring measures should be modified (including additions or deletions). Mitigation measures could be modified if new data suggests that such modifications would have a reasonable likelihood of more effectively accomplishing the goals of the mitigation and monitoring and if the measures are practicable. If the modifications to the mitigation, monitoring, or reporting measures are substantial, NMFS would publish a notice of the planned LOAs in the Federal Register and solicit public comment. The following are some of the possible sources of applicable data to be considered through the adaptive management process: (1) Results from monitoring and exercise reports, as required by MMPA authorizations; (2) compiled results of Navy funded research and development studies; (3) results from specific stranding investigations; (4) results from general marine mammal and sound research; and (5) any information which reveals that marine mammals may have been taken in a manner, extent, or number not authorized by these regulations or subsequent LOAs. The results from monitoring reports and other studies may be viewed at https:// www.navymarinespeciesmonitoring.us. Proposed Reporting In order to issue incidental take authorization for an activity, section 101(a)(5)(A) of the MMPA states that NMFS must set forth requirements pertaining to the monitoring and reporting of such taking. Effective reporting is critical both to compliance as well as ensuring that the most value is obtained from the required monitoring. Reports from individual monitoring events, results of analyses, publications, and periodic progress reports for specific monitoring projects PO 00000 Frm 00093 Fmt 4701 Sfmt 4702 34005 will be posted to the Navy’s Marine Species Monitoring web portal: https:// www.navymarinespeciesmonitoring.us. There are several different reporting requirements pursuant to the current regulations. All of these reporting requirements would be continued under this proposed rule for the seven-year period. Notification of Injured, Live Stranded or Dead Marine Mammals The Navy would consult the Notification and Reporting Plan, which sets out notification, reporting, and other requirements when injured, live stranded, or dead marine mammals are detected. The Notification and Reporting Plan is available for review at https://www.fisheries.noaa.gov/ national/marine-mammal-protection/ incidental-take-authorizations-militaryreadiness-activities. Annual NWTT Monitoring Report The Navy would submit an annual report to NMFS of the NWTT monitoring describing the implementation and results from the previous calendar year. Data collection methods would be standardized across Pacific Range Complexes including the MITT, HSTT, NWTT, and Gulf of Alaska (GOA) Study Areas to allow for comparison in different geographic locations. The draft of the annual monitoring report would be submitted either three months after the end of the calendar year or three months after the conclusion of the monitoring year, to be determined by the Adaptive Management process. NMFS will submit comments or questions on the report, if any, within one month of receipt. The report will be considered final after the Navy has addressed NMFS’ comments, or one month after submittal of the draft if NMFS does not provide comments on the draft report. Such a report would describe progress of knowledge made with respect to intermediate scientific objectives within the NWTT Study Area associated with the ICMP. Similar study questions would be treated together so that summaries can be provided for each topic area. The report need not include analyses and content that do not provide direct assessment of cumulative progress on the monitoring plan study questions. NMFS would submit comments on the draft monitoring report, if any, within three months of receipt. The report would be considered final after the Navy has addressed NMFS’ comments, or three months after the submittal of the draft if NMFS does not have comments. As an alternative, the Navy may submit a Pacific-Range Complex annual E:\FR\FM\02JNP2.SGM 02JNP2 34006 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 Monitoring Plan report to fulfill this requirement. Such a report describes progress of knowledge made with respect to monitoring study questions across multiple Navy ranges associated with the ICMP. Similar study questions would be treated together so that progress on each topic is summarized across multiple Navy ranges. The report need not include analyses and content that does not provide direct assessment of cumulative progress on the monitoring study question. This would continue to allow the Navy to provide a cohesive monitoring report covering multiple ranges (as per ICMP goals), rather than entirely separate reports for the NWTT, GOA, MITT, and HSTT Study Areas. Annual NWTT Training Exercise Report and Testing Activity Reports Each year, the Navy would submit one preliminary report (Quick Look Report) to NMFS detailing the status of applicable sound sources within 21 days after the anniversary of the date of issuance of the LOA. Each year, the Navy would also submit a detailed report (NWTT Annual Training Exercise Report and Testing Activity Report) to NMFS within three months after the one-year anniversary of the date of issuance of the LOA. NMFS will submit comments or questions on the report, if any, within one month of receipt. The report will be considered final after the Navy has addressed NMFS’ comments, or one month after submittal of the draft if NMFS does not provide comments on the draft report. The annual report would contain a summary of all sound sources used (total hours or quantity (per the LOA) of each bin of sonar or other non-impulsive source; total annual number of each type of explosive exercises; and total annual expended/ detonated rounds (missiles, bombs, sonobuoys, etc.) for each explosive bin). The annual report will also contain cumulative sonar and explosive use quantity from previous years’ reports through the current year. Additionally, if there were any changes to the sound source allowance in the reporting year, or cumulatively, the report would include a discussion of why the change was made and include analysis to support how the change did or did not affect the analysis in the NWTT EIS/ OEIS and MMPA final rule. The annual report would also include the details regarding specific requirements associated with specific mitigation areas. The analysis in the detailed report would be based on the accumulation of data from the current year’s report and data collected from previous annual reports. The final annual/close-out VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 report at the conclusion of the authorization period (year seven) would also serve as the comprehensive closeout report and include both the final year annual use compared to annual authorization as well as a cumulative seven-year annual use compared to seven-year authorization. Information included in the annual reports may be used to inform future adaptive management of activities within the NWTT Study Area. The Annual NWTT Training Exercise Report and Testing Activity Navy report (classified or unclassified versions) could be consolidated with other exercise reports from other range complexes in the Pacific Ocean for a single Pacific Exercise Report, if desired. Other Reporting and Coordination The Navy would continue to report and coordinate with NMFS for the following: • Annual marine species monitoring technical review meetings that also include researchers and the Marine Mammal Commission (currently, every two years a joint Pacific-Atlantic meeting is held); and • Annual Adaptive Management meetings that also include the Marine Mammal Commission (recently modified to occur in conjunction with the annual monitoring technical review meeting). Preliminary Analysis and Negligible Impact Determination General Negligible Impact Analysis Introduction NMFS has defined negligible impact as an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival (50 CFR 216.103). A negligible impact finding is based on the lack of likely adverse effects on annual rates of recruitment or survival (i.e., populationlevel effects). An estimate of the number of takes alone is not enough information on which to base an impact determination. For Level A harassment or Level B harassment (as presented in Tables 32 and 33), in addition to considering estimates of the number of marine mammals that might be taken NMFS considers other factors, such as the likely nature of any responses (e.g., intensity, duration) and the context of any responses (e.g., critical reproductive time or location, migration), as well as effects on habitat and the likely effectiveness of the mitigation. We also PO 00000 Frm 00094 Fmt 4701 Sfmt 4702 assess the number, intensity, and context of estimated takes by evaluating this information relative to population status. Consistent with the 1989 preamble for NMFS’ implementing regulations (54 FR 40338; September 29, 1989), the impacts from other past and ongoing anthropogenic activities are incorporated into this analysis via their impacts on the environmental baseline (e.g., as reflected in the regulatory status of the species, population size and growth rate where known, other ongoing sources of human-caused mortality, and ambient noise levels). In the Estimated Take of Marine Mammals section, we identified the subset of potential effects that would be expected to rise to the level of takes both annually and over the seven-year period covered by this proposed rule, and then identified the maximum number of takes we believe could occur (mortality) or are reasonably expected to occur (harassment) based on the methods described. The impact that any given take will have is dependent on many case-specific factors that need to be considered in the negligible impact analysis (e.g., the context of behavioral exposures such as duration or intensity of a disturbance, the health of impacted animals, the status of a species that incurs fitness-level impacts to individuals, etc.). For this proposed rule we evaluated the likely impacts of the enumerated maximum number of harassment takes that are proposed for authorization and reasonably expected to occur, in the context of the specific circumstances surrounding these predicted takes. We also include a specific assessment of serious injury or mortality (hereafter referred to as M/SI) takes that could occur, as well as consideration of the traits and statuses of the affected species and stocks. Last, we collectively evaluated this information, as well as other more taxaspecific information and mitigation measure effectiveness, in group-specific assessments that support our negligible impact conclusions for each stock or species. Because all of the Navy’s specified activities would occur within the ranges of the marine mammal stocks identified in the rule, all negligible impact analyses and determinations are at the stock level (i.e., additional species-level determinations are not needed). Harassment The Specified Activities reflect representative levels of training and testing activities. The Description of the Specified Activity section describes annual activities. There may be some flexibility in the exact number of hours, E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules items, or detonations that may vary from year to year, but take totals would not exceed the maximum annual totals and seven-year totals indicated in Tables 32 and 33. We base our analysis and negligible impact determination on the maximum number of takes that would be reasonably expected to occur annually and are proposed to be authorized, although, as stated before, the number of takes are only a part of the analysis, which includes extensive qualitative consideration of other contextual factors that influence the degree of impact of the takes on the affected individuals. To avoid repetition, we provide some general analysis immediately below that applies to all the species listed in Tables 32 and 33, given that some of the anticipated effects of the Navy’s training and testing activities on marine mammals are expected to be relatively similar in nature. However, below that, we break our analysis into species (and/or stocks), or groups of species (and the associated stocks) where relevant similarities exist, to provide more specific information related to the anticipated effects on individuals of a specific stock or where there is information about the status or structure of any species that would lead to a differing assessment of the effects on the species or stock. Organizing our analysis by grouping species or stocks that share common traits or that will respond similarly to effects of the Navy’s activities and then providing species- or stock-specific information allows us to avoid duplication while assuring that we have analyzed the effects of the specified activities on each affected species or stock. The Navy’s harassment take request is based on its model and quantitative assessment of mitigation, which NMFS reviewed and concurs appropriately predicts the maximum amount of harassment that is reasonably likely to occur. The model calculates sound energy propagation from sonar, other active acoustic sources, and explosives during naval activities; the sound or impulse received by animat dosimeters representing marine mammals distributed in the area around the modeled activity; and whether the sound or impulse energy received by a marine mammal exceeds the thresholds for effects. Assumptions in the Navy model intentionally err on the side of overestimation when there are unknowns. Naval activities are modeled as though they would occur regardless of proximity to marine mammals, meaning that no mitigation is considered (e.g., no power down or shut down) and without any avoidance of the VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 activity by the animal. The final step of the quantitative analysis of acoustic effects, which occurs after the modeling (as described in the Estimated Take of Marine Mammals section), is to consider the implementation of mitigation and the possibility that marine mammals would avoid continued or repeated sound exposures. NMFS provided input to, independently reviewed, and concurred with the Navy on this process and the Navy’s analysis, which is described in detail in Section 6 of the Navy’s rulemaking/LOA application, was used to quantify harassment takes for this rule. Generally speaking, the Navy and NMFS anticipate more severe effects from takes resulting from exposure to higher received levels (though this is in no way a strictly linear relationship for behavioral effects throughout species, individuals, or circumstances) and less severe effects from takes resulting from exposure to lower received levels. However, there is also growing evidence of the importance of distance in predicting marine mammal behavioral response to sound—i.e., sounds of a similar level emanating from a more distant source have been shown to be less likely to evoke a response of equal magnitude (DeRuiter 2012). The estimated number of Level A harassment and Level B harassment takes does not equate to the number of individual animals the Navy expects to harass (which is lower), but rather to the instances of take (i.e., exposures above the Level A harassment and Level B harassment threshold) that are anticipated to occur over the seven-year period. These instances may represent either brief exposures (seconds or minutes) or, in some cases, longer durations of exposure within a day. Some individuals may experience multiple instances of take (meaning over multiple days) over the course of the year, which means that the number of individuals taken is smaller than the total estimated takes. Generally speaking, the higher the number of takes as compared to the population abundance, the more repeated takes of individuals are likely, and the higher the actual percentage of individuals in the population that are likely taken at least once in a year. We look at this comparative metric to give us a relative sense of where a larger portion of a species is being taken by Navy activities, where there is a higher likelihood that the same individuals are being taken across multiple days, and where that number of days might be higher or more likely sequential. Where the number of instances of take is less PO 00000 Frm 00095 Fmt 4701 Sfmt 4702 34007 than 100 percent of the abundance and there is no information to specifically suggest that a small subset of animals is being repeatedly taken over a high number of sequential days, the overall magnitude is generally considered low, as it could on one extreme mean that every take represents a separate individual in the population being taken on one day (a very minimal impact) or, more likely, that some smaller number of individuals are taken on one day annually and some are taken on a few not likely sequential days annually, and of course some are not taken at all. In the ocean, the use of sonar and other active acoustic sources is often transient and is unlikely to repeatedly expose the same individual animals within a short period, for example within one specific exercise. However, for some individuals of some species repeated exposures across different activities could occur over the year, especially where events occur in generally the same area with more resident species. In short, for some species we expect that the total anticipated takes represent exposures of a smaller number of individuals of which some would be exposed multiple times, but based on the nature of the Navy activities and the movement patterns of marine mammals, it is unlikely that individuals from most stocks would be taken over more than a few sequential days. This means that even where repeated takes of individuals are likely to occur, they are more likely to result from nonsequential exposures from different activities, and, even if sequential, individual animals are not predicted to be taken for more than several days in a row, at most. As described elsewhere, the nature of the majority of the exposures would be expected to be of a less severe nature and based on the numbers it is likely that any individual exposed multiple times is still only taken on a small percentage of the days of the year. The greater likelihood is that not every individual is taken, or perhaps a smaller subset is taken with a slightly higher average and larger variability of highs and lows, but still with no reason to think that any individuals would be taken a significant portion of the days of the year, much less that many of the days of disturbance would be sequential. Physiological Stress Response Some of the lower level physiological stress responses (e.g., orientation or startle response, change in respiration, change in heart rate) discussed earlier would likely co-occur with the predicted harassments, although these E:\FR\FM\02JNP2.SGM 02JNP2 34008 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 responses are more difficult to detect and fewer data exist relating these responses to specific received levels of sound. Level B harassment takes, then, may have a stress-related physiological component as well; however, we would not expect the Navy’s generally shortterm, intermittent, and (typically in the case of sonar) transitory activities to create conditions of long-term continuous noise leading to long-term physiological stress responses in marine mammals that could affect reproduction or survival. Behavioral Response The estimates calculated using the behavioral response function do not differentiate between the different types of behavioral responses that rise to the level of Level B harassments. As described in the Navy’s application, the Navy identified (with NMFS’ input) the types of behaviors that would be considered a take (moderate behavioral responses as characterized in Southall et al. (2007) (e.g., altered migration paths or dive profiles, interrupted nursing, breeding or feeding, or avoidance) that also would be expected to continue for the duration of an exposure). The Navy then compiled the available data indicating at what received levels and distances those responses have occurred, and used the indicated literature to build biphasic behavioral response curves that are used to predict how many instances of Level B behavioral harassment occur in a day. Take estimates alone do not provide information regarding the potential fitness or other biological consequences of the reactions on the affected individuals. We therefore consider the available activity-specific, environmental, and species-specific information to determine the likely nature of the modeled behavioral responses and the potential fitness consequences for affected individuals. Use of sonar and other transducers would typically be transient and temporary. The majority of acoustic effects to individual animals from sonar and other active sound sources during training and testing activities would be primarily from ASW events. Unlike other Navy training and testing Study Areas, no major training exercises (MTEs) are proposed in the NWTT Study Area. In the range of potential behavioral effects that might expect to be part of a response that qualifies as an instance of Level B behavioral harassment (which by nature of the way it is modeled/counted, occurs within one day), the less severe end might include exposure to comparatively lower levels of a sound, at a detectably VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 greater distance from the animal, for a few or several minutes. A less severe exposure of this nature could result in a behavioral response such as avoiding an area that an animal would otherwise have chosen to move through or feed in for some amount of time or breaking off one or a few feeding bouts. More severe effects could occur when the animal gets close enough to the source to receive a comparatively higher level of sound, is exposed continuously to one source for a longer time, or is exposed intermittently to different sources throughout a day. Such effects might result in an animal having a more severe flight response and leaving a larger area for a day or more or potentially losing feeding opportunities for a day. However, such severe behavioral effects are expected to occur infrequently. To help assess this, for sonar (LFAS/ MFAS/HFAS) used in the NWTT Study Area, the Navy provided information estimating the percentage of animals that may be taken by Level B harassment under each behavioral response function that would occur within 6-dB increments (percentages discussed below in the Group and Species-Specific Analyses section). As mentioned above, all else being equal, an animal’s exposure to a higher received level is more likely to result in a behavioral response that is more likely to lead to adverse effects, which could more likely accumulate to impacts on reproductive success or survivorship of the animal, but other contextual factors (such as distance) are also important. The majority of Level B harassment takes are expected to be in the form of milder responses (i.e., lower-level exposures that still rise to the level of take, but would likely be less severe in the range of responses that qualify as take) of a generally shorter duration. We anticipate more severe effects from takes when animals are exposed to higher received levels of sound or at closer proximity to the source. Because species belonging to taxa that share common characteristics are likely to respond and be affected in similar ways, these discussions are presented within each species group below in the Group and Species-Specific Analyses section. As noted previously in this proposed rule, behavioral response is likely highly variable between species, individuals within a species, and context of the exposure. Specifically, given a range of behavioral responses that may be classified as Level B harassment, to the degree that higher received levels of sound are expected to result in more severe behavioral responses, only a smaller percentage of the anticipated PO 00000 Frm 00096 Fmt 4701 Sfmt 4702 Level B harassment from Navy activities might necessarily be expected to potentially result in more severe responses (see the Group and SpeciesSpecific Analyses section below for more detailed information). To fully understand the likely impacts of the predicted/proposed authorized take on an individual (i.e., what is the likelihood or degree of fitness impacts), one must look closely at the available contextual information, such as the duration of likely exposures and the likely severity of the exposures (e.g., whether they will occur for a longer duration over sequential days or the comparative sound level that will be received). Ellison et al. (2012) and Moore and Barlow (2013), among others emphasize the importance of context (e.g., behavioral state of the animals, distance from the sound source, etc.) in evaluating behavioral responses of marine mammals to acoustic sources. Diel Cycle Many animals perform vital functions, such as feeding, resting, traveling, and socializing on a diel cycle (24-hour cycle). Behavioral reactions to noise exposure, when taking place in a biologically important context, such as disruption of critical life functions, displacement, or avoidance of important habitat, are more likely to be significant if they last more than one diel cycle or recur on subsequent days (Southall et al., 2007). Henderson et al. (2016) found that ongoing smaller scale events had little to no impact on foraging dives for Blainville’s beaked whale, while multiday training events may decrease foraging behavior for Blainville’s beaked whale (Manzano-Roth et al., 2016). Consequently, a behavioral response lasting less than one day and not recurring on subsequent days is not considered severe unless it could directly affect reproduction or survival (Southall et al., 2007). Note that there is a difference between multiple-day substantive behavioral reactions and multiple-day anthropogenic activities. For example, just because an at-sea exercise lasts for multiple days does not necessarily mean that individual animals are either exposed to those exercises for multiple days or, further, exposed in a manner resulting in a sustained multiple day substantive behavioral response. Large multi-day Navy exercises such as ASW activities, typically include vessels that are continuously moving at speeds typically 10–15 kn, or higher, and likely cover large areas that are relatively far from shore (typically more than 3 nmi from shore) and in waters greater than 600 ft deep. Additionally marine mammals are E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules moving as well, which would make it unlikely that the same animal could remain in the immediate vicinity of the ship for the entire duration of the exercise. Further, the Navy does not necessarily operate active sonar the entire time during an exercise. While it is certainly possible that these sorts of exercises could overlap with individual marine mammals multiple days in a row at levels above those anticipated to result in a take, because of the factors mentioned above, it is considered unlikely for the majority of takes. However, it is also worth noting that the Navy conducts many different types of noise-producing activities over the course of the year and it is likely that some marine mammals will be exposed to more than one activity and taken on multiple days, even if they are not sequential. Durations of Navy activities utilizing tactical sonar sources and explosives vary and are fully described in Appendix A (Navy Activity Descriptions) of the 2019 NWTT DSEIS/ OEIS. Sonar used during ASW would impart the greatest amount of acoustic energy of any category of sonar and other transducers analyzed in the Navy’s rulemaking/LOA application and include hull-mounted, towed, line array, sonobuoy, helicopter dipping, and torpedo sonars. Most ASW sonars are MFAS (1–10 kHz); however, some sources may use higher or lower frequencies. ASW training activities using hull mounted sonar proposed for the NWTT Study Area generally last for only a few hours (see Table 3). Some ASW testing activities range from several hours, to days, to up to 3 weeks for Pierside-Sonar Testing and Submarine Sonar Testing/Maintenance (see Table 4). For these multi-day exercises there will typically be extended intervals of non-activity in between active sonar periods. Because of the need to train in a large variety of situations, the Navy does not typically conduct successive ASW exercises in the same locations. Given the average length of ASW exercises (times of sonar use) and typical vessel speed, combined with the fact that the majority of the cetaceans would not likely remain in proximity to the sound source, it is unlikely that an animal would be exposed to LFAS/MFAS/HFAS at levels or durations likely to result in a substantive response that would then be carried on for more than one day or on successive days. Most planned explosive events are scheduled to occur over a short duration (1–8 hours); however Mine Countermeasure and Neutralization Testing would last 1–10 days (see VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Tables 3 and 4). The explosive component of these activities only lasts for minutes. Although explosive exercises may sometimes be conducted in the same general areas repeatedly, because of their short duration and the fact that they are in the open ocean and animals can easily move away, it is similarly unlikely that animals would be exposed for long, continuous amounts of time, or demonstrate sustained behavioral responses. All of these factors make it unlikely that individuals would be exposed to the exercise for extended periods or on consecutive days. Assessing the Number of Individuals Taken and the Likelihood of Repeated Takes As described previously, Navy modeling uses the best available science to predict the instances of exposure above certain acoustic thresholds, which are equated, as appropriate, to harassment takes (and further corrected to account for mitigation and avoidance). As further noted, for active acoustics it is more challenging to parse out the number of individuals taken by Level B harassment and the number of times those individuals are taken from this larger number of instances. One method that NMFS uses to help better understand the overall scope of the impacts is to compare these total instances of take against the abundance of that species (or stock if applicable). For example, if there are 100 harassment takes in a population of 100, one can assume either that every individual was exposed above acoustic thresholds in no more than one day, or that some smaller number were exposed in one day but a few of those individuals were exposed multiple days within a year and a few were not exposed at all. Where the instances of take exceed 100 percent of the population, multiple takes of some individuals are predicted and expected to occur within a year. Generally speaking, the higher the number of takes as compared to the population abundance, the more multiple takes of individuals are likely, and the higher the actual percentage of individuals in the population that are likely taken at least once in a year. We look at this comparative metric to give us a relative sense of where larger portions of the species are being taken by Navy activities and where there is a higher likelihood that the same individuals are being taken across multiple days and where that number of days might be higher. It also provides a relative picture of the scale of impacts to each species. In the ocean, unlike a modeling simulation with static animals, the use PO 00000 Frm 00097 Fmt 4701 Sfmt 4702 34009 of sonar and other active acoustic sources is often transient, and is unlikely to repeatedly expose the same individual animals within a short period, for example within one specific exercise. However, some repeated exposures across different activities could occur over the year with more resident species. In short, we expect that the total anticipated takes represent exposures of a smaller number of individuals of which some could be exposed multiple times, but based on the nature of the Navy’s activities and the movement patterns of marine mammals, it is unlikely that any particular subset would be taken over more than several sequential days (with a few possible exceptions discussed in the species-specific conclusions). When calculating the proportion of a population affected by takes (e.g., the number of takes divided by population abundance), which can also be helpful in estimating the number of days over which some individuals may be taken, it is important to choose an appropriate population estimate against which to make the comparison. The SARs, where available, provide the official population estimate for a given species or stock in U.S. waters in a given year (and are typically based solely on the most recent survey data). When the stock is known to range well outside of U.S. Exclusive Economic Zone (EEZ) boundaries, population estimates based on surveys conducted only within the U.S. EEZ are known to be underestimates. The information used to estimate take includes the best available survey abundance data to model density layers. Accordingly, in calculating the percentage of takes versus abundance for each species in order to assist in understanding both the percentage of the species affected, as well as how many days across a year individuals could be taken, we use the data most appropriate for the situation. For all species and stocks except for a few stocks of harbor seals for which SAR data are unavailable and Navy abundance surveys of the inland areas of the NWTT Study Area are used, the most recent NMFS SARs are used to calculate the proportion of a population affected by takes. The estimates found in NMFS’ SARs remain the official estimates of stock abundance where they are current. These estimates are typically generated from the most recent shipboard and/or aerial surveys conducted. In some cases, NMFS’ abundance estimates show substantial year-to-year variability. However, for highly migratory species (e.g., large whales) or those whose geographic distribution extends well E:\FR\FM\02JNP2.SGM 02JNP2 34010 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 beyond the boundaries of the NWTT Study Area (e.g., populations with distribution along the entire eastern Pacific Ocean rather than just the NWTT Study Area), comparisons to the SAR are appropriate. Many of the stocks present in the NWTT Study Area have ranges significantly larger than the NWTT Study Area and that abundance is captured by the SAR. A good descriptive example is migrating large whales, which traverse the NWTT Study Area for several days to weeks on their migrations. Therefore, at any one time there may be a stable number of animals, but over the course of the entire year the entire population may pass through the NWTT Study Area. Therefore, comparing the estimated takes to an abundance, in this case the SAR abundance, which represents the total population, may be more appropriate than modeled abundances for only the NWTT Study Area. Temporary Threshold Shift NMFS and the Navy have estimated that all species of marine mammals may sustain some level of TTS from active sonar. As mentioned previously, in general, TTS can last from a few minutes to days, be of varying degree, and occur across various frequency bandwidths, all of which determine the severity of the impacts on the affected individual, which can range from minor to more severe. Tables 52–57 indicate the number of takes by TTS that may be incurred by different species from exposure to active sonar and explosives. The TTS sustained by an animal is primarily classified by three characteristics: 1. Frequency—Available data (of midfrequency hearing specialists exposed to mid- or high-frequency sounds; Southall et al., 2007) suggest that most TTS occurs in the frequency range of the source up to one octave higher than the source (with the maximum TTS at 1⁄2 octave above). The Navy’s MF sources, which are the highest power and most numerous sources and the ones that cause the most take, utilize the 1–10 kHz frequency band, which suggests that if TTS were to be induced by any of these MF sources it would be in a frequency band somewhere between approximately 2 and 20 kHz, which is in the range of communication calls for many odontocetes, but below the range of the echolocation signals used for foraging. There are fewer hours of HF source use and the sounds would attenuate more quickly, plus they have lower source levels, but if an animal were to incur TTS from these sources, it would cover a higher frequency range (sources are between 10 and 100 kHz, VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 which means that TTS could range up to 200 kHz), which could overlap with the range in which some odontocetes communicate or echolocate. However, HF systems are typically used less frequently and for shorter time periods than surface ship and aircraft MF systems, so TTS from these sources is unlikely. There are fewer LF sources and the majority are used in the more readily mitigated testing environment, and TTS from LF sources would most likely occur below 2 kHz, which is in the range where many mysticetes communicate and also where other noncommunication auditory cues are located (waves, snapping shrimp, fish prey). Also of note, the majority of sonar sources from which TTS may be incurred occupy a narrow frequency band, which means that the TTS incurred would also be across a narrower band (i.e., not affecting the majority of an animal’s hearing range). This frequency provides information about the cues to which a marine mammal may be temporarily less sensitive, but not the degree or duration of sensitivity loss. TTS from explosives would be broadband. 2. Degree of the shift (i.e., by how many dB the sensitivity of the hearing is reduced)—Generally, both the degree of TTS and the duration of TTS will be greater if the marine mammal is exposed to a higher level of energy (which would occur when the peak dB level is higher or the duration is longer). The threshold for the onset of TTS was discussed previously in this rule. An animal would have to approach closer to the source or remain in the vicinity of the sound source appreciably longer to increase the received SEL, which would be difficult considering the Lookouts and the nominal speed of an active sonar vessel (10–15 kn) and the relative motion between the sonar vessel and the animal. In the TTS studies discussed in the Potential Effects of Specified Activities on Marine Mammals and their Habitat section, some using exposures of almost an hour in duration or up to 217 SEL, most of the TTS induced was 15 dB or less, though Finneran et al. (2007) induced 43 dB of TTS with a 64second exposure to a 20 kHz source. However, since any hull-mounted sonar such as the SQS–53 (MFAS), emits a ping typically every 50 seconds, incurring those levels of TTS is highly unlikely. Since any hull-mounted sonar, such as the SQS–53, engaged in antisubmarine warfare training would be moving at between 10 and 15 knots and nominally pinging every 50 seconds, the vessel will have traveled a minimum distance of approximately 257 m during PO 00000 Frm 00098 Fmt 4701 Sfmt 4702 the time between those pings. A scenario could occur where an animal does not leave the vicinity of a ship or travels a course parallel to the ship, however, the close distances required make TTS exposure unlikely. For a Navy vessel moving at a nominal 10 knots, it is unlikely a marine mammal could maintain speed parallel to the ship and receive adequate energy over successive pings to suffer TTS. In short, given the anticipated duration and levels of sound exposure, we would not expect marine mammals to incur more than relatively low levels of TTS (i.e., single digits of sensitivity loss). To add context to this degree of TTS, individual marine mammals may regularly experience variations of 6 dB differences in hearing sensitivity across time (Finneran et al., 2000, 2002; Schlundt et al., 2000). 3. Duration of TTS (recovery time)— In the TTS laboratory studies (as discussed in the Potential Effects of Specified Activities on Marine Mammals and their Habitat section), some using exposures of almost an hour in duration or up to 217 SEL, almost all individuals recovered within 1 day (or less, often in minutes), although in one study (Finneran et al., 2007), recovery took 4 days. Based on the range of degree and duration of TTS reportedly induced by exposures to non-pulse sounds of energy higher than that to which freeswimming marine mammals in the field are likely to be exposed during LFAS/ MFAS/HFAS training and testing exercises in the NWTT Study Area, it is unlikely that marine mammals would ever sustain a TTS from MFAS that alters their sensitivity by more than 20 dB for more than a few hours—and any incident of TTS would likely be far less severe due to the short duration of the majority of the events and the speed of a typical vessel, especially given the fact that the higher power sources resulting in TTS are predominantly intermittent, which have been shown to result in shorter durations of TTS. Also, for the same reasons discussed in the Preliminary Analysis and Negligible Impact Determination—Diel Cycle section, and because of the short distance within which animals would need to approach the sound source, it is unlikely that animals would be exposed to the levels necessary to induce TTS in subsequent time periods such that their recovery is impeded. Additionally, though the frequency range of TTS that marine mammals might sustain would overlap with some of the frequency ranges of their vocalization types, the frequency range of TTS from MFAS would not usually span the entire E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules frequency range of one vocalization type, much less span all types of vocalizations or other critical auditory cues. Tables 52–57 indicate the number of incidental takes by TTS for each species that are likely to result from the Navy’s activities. As a general point, the majority of these TTS takes are the result of exposure to hull-mounted MFAS (MF narrower band sources), with fewer from explosives (broad-band lower frequency sources), and even fewer from LFAS or HFAS sources (narrower band). As described above, we expect the majority of these takes to be in the form of mild (single-digit), short-term (minutes to hours), narrower band (only affecting a portion of the animal’s hearing range) TTS. This means that for one to several times per year, for several minutes to maybe a few hours at most each, a taken individual will have slightly diminished hearing sensitivity (slightly more than natural variation, but nowhere near total deafness). More often than not, such an exposure would occur within a narrower mid- to higher frequency band that may overlap part (but not all) of a communication, echolocation, or predator range, but sometimes across a lower or broader bandwidth. The significance of TTS is also related to the auditory cues that are germane within the time period that the animal incurs the TTS. For example, if an odontocete has TTS at echolocation frequencies, but incurs it at night when it is resting and not feeding, it is not impactful. In short, the expected results of any one of these small number of mild TTS occurrences could be that (1) it does not overlap signals that are pertinent to that animal in the given time period, (2) it overlaps parts of signals that are important to the animal, but not in a manner that impairs interpretation, or (3) it reduces detectability of an important signal to a small degree for a short amount of time—in which case the animal may be aware and be able to compensate (but there may be slight energetic cost), or the animal may have some reduced opportunities (e.g., to detect prey) or reduced capabilities to react with maximum effectiveness (e.g., to detect a predator or navigate optimally). However, given the small number of times that any individual might incur TTS, the low degree of TTS and the short anticipated duration, and the low likelihood that one of these instances would occur in a time period in which the specific TTS overlapped the entirety of a critical signal, it is unlikely that TTS of the nature expected to result from the Navy activities would result in VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 behavioral changes or other impacts that would impact any individual’s (of any hearing sensitivity) reproduction or survival. Auditory Masking or Communication Impairment The ultimate potential impacts of masking on an individual (if it were to occur) are similar to those discussed for TTS, but an important difference is that masking only occurs during the time of the signal, versus TTS, which continues beyond the duration of the signal. Fundamentally, masking is referred to as a chronic effect because one of the key harmful components of masking is its duration—the fact that an animal would have reduced ability to hear or interpret critical cues becomes much more likely to cause a problem the longer it is occurring. Also inherent in the concept of masking is the fact that the potential for the effect is only present during the times that the animal and the source are in close enough proximity for the effect to occur (and further, this time period would need to coincide with a time that the animal was utilizing sounds at the masked frequency). As our analysis has indicated, because of the relative movement of vessels and the species involved in this rule, we do not expect the exposures with the potential for masking to be of a long duration. In addition, masking is fundamentally more of a concern at lower frequencies, because low frequency signals propagate significantly further than higher frequencies and because they are more likely to overlap both the narrower LF calls of mysticetes, as well as many noncommunication cues such as fish and invertebrate prey, and geologic sounds that inform navigation. Masking is also more of a concern from continuous sources (versus intermittent sonar signals) where there is no quiet time between pulses within which auditory signals can be detected and interpreted. For these reasons, dense aggregations of, and long exposure to, continuous LF activity are much more of a concern for masking, whereas comparatively shortterm exposure to the predominantly intermittent pulses of often narrow frequency range MFAS or HFAS, or explosions are not expected to result in a meaningful amount of masking. While the Navy occasionally uses LF and more continuous sources, it is not in the contemporaneous aggregate amounts that would accrue to a masking concern. Specifically, the nature of the activities and sound sources used by the Navy do not support the likelihood of a level of masking accruing that would have the potential to affect reproductive success PO 00000 Frm 00099 Fmt 4701 Sfmt 4702 34011 or survival. Additional detail is provided below. Standard hull-mounted MFAS typically pings every 50 seconds. Some hull-mounted anti-submarine sonars can also be used in an object detection mode known as ‘‘Kingfisher’’ mode (e.g., used on vessels when transiting to and from port) where pulse length is shorter but pings are much closer together in both time and space since the vessel goes slower when operating in this mode. For the majority of other sources, the pulse length is significantly shorter than hullmounted active sonar, on the order of several microseconds to tens of milliseconds. Some of the vocalizations that many marine mammals make are less than one second long, so, for example with hull-mounted sonar, there would be a 1 in 50 chance (only if the source was in close enough proximity for the sound to exceed the signal that is being detected) that a single vocalization might be masked by a ping. However, when vocalizations (or series of vocalizations) are longer than one second, masking would not occur. Additionally, when the pulses are only several microseconds long, the majority of most animals’ vocalizations would not be masked. Most ASW sonars and countermeasures use MF frequencies and a few use LF and HF frequencies. Most of these sonar signals are limited in the temporal, frequency, and spatial domains. The duration of most individual sounds is short, lasting up to a few seconds each. A few systems operate with higher duty cycles or nearly continuously, but they typically use lower power, which means that an animal would have to be closer, or in the vicinity for a longer time, to be masked to the same degree as by a higher level source. Nevertheless, masking could occasionally occur at closer ranges to these high-duty cycle and continuous active sonar systems, but as described previously, it would be expected to be of a short duration when the source and animal are in close proximity. While data are lacking on behavioral responses of marine mammals to continuously active sonars, mysticete species are known to be able to habituate to novel and continuous sounds (Nowacek et al., 2004), suggesting that they are likely to have similar responses to high-duty cycle sonars. Furthermore, most of these systems are hull-mounted on surface ships with the ships moving at least 10 kn, and it is unlikely that the ship and the marine mammal would continue to move in the same direction and the marine mammal subjected to the same exposure due to that movement. Most E:\FR\FM\02JNP2.SGM 02JNP2 34012 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 ASW activities are geographically dispersed and last for only a few hours, often with intermittent sonar use even within this period. Most ASW sonars also have a narrow frequency band (typically less than one-third octave). These factors reduce the likelihood of sources causing significant masking. HF signals (above 10 kHz) attenuate more rapidly in the water due to absorption than do lower frequency signals, thus producing only a very small zone of potential masking. If masking or communication impairment were to occur briefly, it would more likely be in the frequency range of MFAS (the more powerful source), which overlaps with some odontocete vocalizations (but few mysticete vocalizations); however, it would likely not mask the entirety of any particular vocalization, communication series, or other critical auditory cue, because the signal length, frequency, and duty cycle of the MFAS/ HFAS signal does not perfectly resemble the characteristics of any single marine mammal species’ vocalizations. Other sources used in Navy training and testing that are not explicitly addressed above, many of either higher frequencies (meaning that the sounds generated attenuate even closer to the source) or lower amounts of operation, are similarly not expected to result in masking. For the reasons described here, any limited masking that could potentially occur would be minor and short-term. In conclusion, masking is more likely to occur in the presence of broadband, relatively continuous noise sources such as from vessels, however, the duration of temporal and spatial overlap with any individual animal and the spatially separated sources that the Navy uses would not be expected to result in more than short-term, low impact masking that would not affect reproduction or survival. PTS from Sonar Acoustic Sources and Explosives and Tissue Damage from Explosives Tables 52 through 57 indicate the number of individuals of each species for which Level A harassment in the form of PTS resulting from exposure to active sonar and/or explosives is estimated to occur. The number of individuals to potentially incur PTS annually (from sonar and explosives) for each species/stock ranges from 0 to 180 (the 180 is for the Inland Washington stock of harbor porpoise), but is more typically 0 or 1. No species/stocks have the potential to incur tissue damage from sonar or explosives. Data suggest that many marine mammals would deliberately avoid VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 exposing themselves to the received levels of active sonar necessary to induce injury by moving away from or at least modifying their path to avoid a close approach. Additionally, in the unlikely event that an animal approaches the sonar-emitting vessel at a close distance, NMFS has determined that the mitigation measures (i.e., shutdown/powerdown zones for active sonar) would typically ensure that animals would not be exposed to injurious levels of sound. As discussed previously, the Navy utilizes both aerial (when available) and passive acoustic monitoring (during ASW exercises, passive acoustic detections are used as a cue for Lookouts’ visual observations when passive acoustic assets are already participating in an activity) in addition to Lookouts on vessels to detect marine mammals for mitigation implementation. As discussed previously, the Navy utilized a postmodeling quantitative assessment to adjust the take estimates based on avoidance and the likely success of some portion of the mitigation measures. As is typical in predicting biological responses, it is challenging to predict exactly how avoidance and mitigation will affect the take of marine mammals, and therefore the Navy erred on the side of caution in choosing a method that would more likely still overestimate the take by PTS to some degree. Nonetheless, these modified Level A harassment take numbers represent the maximum number of instances in which marine mammals would be reasonably expected to incur PTS, and we have analyzed them accordingly. If a marine mammal is able to approach a surface vessel within the distance necessary to incur PTS in spite of the mitigation measures, the likely speed of the vessel (nominally 10–15 kn) and relative motion of the vessel would make it very difficult for the animal to remain in range long enough to accumulate enough energy to result in more than a mild case of PTS. As discussed previously in relation to TTS, the likely consequences to the health of an individual that incurs PTS can range from mild to more serious dependent upon the degree of PTS and the frequency band it is in. The majority of any PTS incurred as a result of exposure to Navy sources would be expected to be in the 2–20 kHz range (resulting from the most powerful hull-mounted sonar) and could overlap a small portion of the communication frequency range of many odontocetes, whereas other marine mammal groups have communication calls at lower PO 00000 Frm 00100 Fmt 4701 Sfmt 4702 frequencies. Regardless of the frequency band, the more important point in this case is that any PTS accrued as a result of exposure to Navy activities would be expected to be of a small amount (single digits). Permanent loss of some degree of hearing is a normal occurrence for older animals, and many animals are able to compensate for the shift, both in old age or at younger ages as the result of stressor exposure. While a small loss of hearing sensitivity may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, at the expected scale it would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival. The Navy implements mitigation measures (described in the Proposed Mitigation Measures section) during explosive activities, including delaying detonations when a marine mammal is observed in the mitigation zone. Nearly all explosive events would occur during daylight hours to improve the sightability of marine mammals and thereby improve mitigation effectiveness. Observing for marine mammals during the explosive activities would include visual and passive acoustic detection methods (when they are available and part of the activity) before the activity begins, in order to cover the mitigation zones that can range from 600 yds (656 m) to 2,500 yds (2,286 m) depending on the source (e.g., explosive sonobuoy, explosive torpedo, explosive bombs; see Tables 38–44). For all of these reasons, the proposed mitigation measures associated with explosives are expected to be effective in preventing tissue damage to any potentially affected species, and no species are anticipated to incur tissue damage during the period of the proposed rule. Serious Injury and Mortality NMFS is authorizing a very small number of serious injuries or mortalities that could occur in the event of a ship strike. We note here that the takes from potential ship strikes enumerated below could result in non-serious injury, but their worst potential outcome (mortality) is analyzed for the purposes of the negligible impact determination. In addition, we discuss here the connection, and differences, between the legal mechanisms for authorizing incidental take under section 101(a)(5) for activities such as the Navy’s testing and training in the NWTT Study Area, and for authorizing incidental take from commercial fisheries. In 1988, Congress amended the MMPA’s provisions for E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules addressing incidental take of marine mammals in commercial fishing operations. Congress directed NMFS to develop and recommend a new longterm regime to govern such incidental taking (see MMC, 1994). The need to develop a system suited to the unique circumstances of commercial fishing operations led NMFS to suggest a new conceptual means and associated regulatory framework. That concept, PBR, and a system for developing plans containing regulatory and voluntary measures to reduce incidental take for fisheries that exceed PBR were incorporated as sections 117 and 118 in the 1994 amendments to the MMPA. In Conservation Council for Hawaii v. National Marine Fisheries Service, 97 F. Supp. 3d 1210 (D. Haw. 2015), which concerned a challenge to NMFS’ regulations and LOAs to the Navy for activities assessed in the 2013–2018 HSTT MMPA rulemaking, the Court ruled that NMFS’ failure to consider PBR when evaluating lethal takes in the negligible impact analysis under section 101(a)(5)(A) violated the requirement to use the best available science. PBR is defined in section 3 of the MMPA as ‘‘the maximum number of animals, not including natural mortalities, that may be removed from a marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population’’ (OSP) and, although not controlling, can be one measure considered among other factors when evaluating the effects of M/ SI on a marine mammal species or stock during the section 101(a)(5)(A) process. OSP is defined in section 3 of the MMPA as ‘‘the number of animals which will result in the maximum productivity of the population or the species, keeping in mind the carrying capacity of the habitat and the health of the ecosystem of which they form a constituent element.’’ Through section 2, an overarching goal of the statute is to ensure that each species or stock of marine mammal is maintained at or returned to its OSP. PBR values are calculated by NMFS as the level of annual removal from a stock that will allow that stock to equilibrate within OSP at least 95 percent of the time, and is the product of factors relating to the minimum population estimate of the stock (Nmin), the productivity rate of the stock at a small population size, and a recovery factor. Determination of appropriate values for these three elements incorporates significant precaution, such that application of the parameter to the management of marine mammal stocks may be reasonably certain to achieve the goals of the MMPA. For example, VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 calculation of the minimum population estimate (Nmin) incorporates the level of precision and degree of variability associated with abundance information, while also providing reasonable assurance that the stock size is equal to or greater than the estimate (Barlow et al., 1995), typically by using the 20th percentile of a log-normal distribution of the population estimate. In general, the three factors are developed on a stock-specific basis in consideration of one another in order to produce conservative PBR values that appropriately account for both imprecision that may be estimated, as well as potential bias stemming from lack of knowledge (Wade, 1998). Congress called for PBR to be applied within the management framework for commercial fishing incidental take under section 118 of the MMPA. As a result, PBR cannot be applied appropriately outside of the section 118 regulatory framework without consideration of how it applies within the section 118 framework, as well as how the other statutory management frameworks in the MMPA differ from the framework in section 118. PBR was not designed and is not used as an absolute threshold limiting commercial fisheries. Rather, it serves as a means to evaluate the relative impacts of those activities on marine mammal stocks. Even where commercial fishing is causing M/SI at levels that exceed PBR, the fishery is not suspended. When M/ SI exceeds PBR in the commercial fishing context under section 118, NMFS may develop a take reduction plan, usually with the assistance of a take reduction team. The take reduction plan will include measures to reduce and/or minimize the taking of marine mammals by commercial fisheries to a level below the stock’s PBR. That is, where the total annual human-caused M/SI exceeds PBR, NMFS is not required to halt fishing activities contributing to total M/SI but rather utilizes the take reduction process to further mitigate the effects of fishery activities via additional bycatch reduction measures. In other words, under section 118 of the MMPA, PBR does not serve as a strict cap on the operation of commercial fisheries that may incidentally take marine mammals. Similarly, to the extent PBR may be relevant when considering the impacts of incidental take from activities other than commercial fisheries, using it as the sole reason to deny (or issue) incidental take authorization for those activities would be inconsistent with Congress’s intent under section 101(a)(5), NMFS’ long-standing regulatory definition of ‘‘negligible PO 00000 Frm 00101 Fmt 4701 Sfmt 4702 34013 impact,’’ and the use of PBR under section 118. The standard for authorizing incidental take for activities other than commercial fisheries under section 101(a)(5) continues to be, among other things that are not related to PBR, whether the total taking will have a negligible impact on the species or stock. Nowhere does section 101(a)(5)(A) reference use of PBR to make the negligible impact finding or authorize incidental take through multiyear regulations, nor does its companion provision at 101(a)(5)(D) for authorizing non-lethal incidental take under the same negligible-impact standard. NMFS’ MMPA implementing regulations state that take has a negligible impact when it does not ‘‘adversely affect the species or stock through effects on annual rates of recruitment or survival’’—likewise without reference to PBR. When Congress amended the MMPA in 1994 to add section 118 for commercial fishing, it did not alter the standards for authorizing non-commercial fishing incidental take under section 101(a)(5), implicitly acknowledging that the negligible impact standard under section 101(a)(5) is separate from the PBR metric under section 118. In fact, in 1994 Congress also amended section 101(a)(5)(E) (a separate provision governing commercial fishing incidental take for species listed under the ESA) to add compliance with the new section 118 but retained the standard of the negligible impact finding under section 101(a)(5)(A) (and section 101(a)(5)(D)), showing that Congress understood that the determination of negligible impact and application of PBR may share certain features but are, in fact, different. Since the introduction of PBR in 1994, NMFS had used the concept almost entirely within the context of implementing sections 117 and 118 and other commercial fisheries managementrelated provisions of the MMPA. Prior to the Court’s ruling in Conservation Council for Hawaii v. National Marine Fisheries Service and consideration of PBR in a series of section 101(a)(5) rulemakings, there were a few examples where PBR had informed agency deliberations under other MMPA sections and programs, such as playing a role in the issuance of a few scientific research permits and subsistence takings. But as the Court found when reviewing examples of past PBR consideration in Georgia Aquarium v. Pritzker, 135 F. Supp. 3d 1280 (N.D. Ga. 2015), where NMFS had considered PBR outside the commercial fisheries context, ‘‘it has treated PBR as only one ‘quantitative tool’ and [has not used it] E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 34014 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules as the sole basis for its impact analyses.’’ Further, the agency’s thoughts regarding the appropriate role of PBR in relation to MMPA programs outside the commercial fishing context have evolved since the agency’s early application of PBR to section 101(a)(5) decisions. Specifically, NMFS’ denial of a request for incidental take authorization for the U.S. Coast Guard in 1996 seemingly was based on the potential for lethal take in relation to PBR and did not appear to consider other factors that might also have informed the potential for ship strike in relation to negligible impact (61 FR 54157; October 17, 1996). The MMPA requires that PBR be estimated in SARs and that it be used in applications related to the management of take incidental to commercial fisheries (i.e., the take reduction planning process described in section 118 of the MMPA and the determination of whether a stock is ‘‘strategic’’ as defined in section 3), but nothing in the statute requires the application of PBR outside the management of commercial fisheries interactions with marine mammals. Nonetheless, NMFS recognizes that as a quantitative metric, PBR may be useful as a consideration when evaluating the impacts of other human-caused activities on marine mammal stocks. Outside the commercial fishing context, and in consideration of all known human-caused mortality, PBR can help inform the potential effects of M/SI requested to be authorized under 101(a)(5)(A). As noted by NMFS and the U.S. Fish and Wildlife Service in our implementation regulations for the 1986 amendments to the MMPA (54 FR 40341, September 29, 1989), the Services consider many factors, when available, in making a negligible impact determination, including, but not limited to, the status of the species or stock relative to OSP (if known); whether the recruitment rate for the species or stock is increasing, decreasing, stable, or unknown; the size and distribution of the population; and existing impacts and environmental conditions. In this multi-factor analysis, PBR can be a useful indicator for when, and to what extent, the agency should take an especially close look at the circumstances associated with the potential mortality, along with any other factors that could influence annual rates of recruitment or survival. When considering PBR during evaluation of effects of M/SI under section 101(a)(5)(A), we first calculate a metric for each species or stock that incorporates information regarding ongoing anthropogenic M/SI from all VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 sources into the PBR value (i.e., PBR minus the total annual anthropogenic mortality/serious injury estimate in the SAR), which is called ‘‘residual PBR.’’ (Wood et al., 2012). We first focus our analysis on residual PBR because it incorporates anthropogenic mortality occurring from other sources. If the ongoing human-caused mortality from other sources does not exceed PBR, then residual PBR is a positive number, and we consider how the anticipated or potential incidental M/SI from the activities being evaluated compares to residual PBR using the framework in the following paragraph. If the ongoing anthropogenic mortality from other sources already exceeds PBR, then residual PBR is a negative number and we consider the M/SI from the activities being evaluated as described further below. When ongoing total anthropogenic mortality from the applicant’s specified activities does not exceed PBR and residual PBR is a positive number, as a simplifying analytical tool we first consider whether the specified activities could cause incidental M/SI that is less than 10 percent of residual PBR (the ‘‘insignificance threshold,’’ see below). If so, we consider M/SI from the specified activities to represent an insignificant incremental increase in ongoing anthropogenic M/SI for the marine mammal stock in question that alone (i.e., in the absence of any other take) will not adversely affect annual rates of recruitment and survival. As such, this amount of M/SI would not be expected to affect rates of recruitment or survival in a manner resulting in more than a negligible impact on the affected stock unless there are other factors that could affect reproduction or survival, such as Level A and/or Level B harassment, or other considerations such as information that illustrates uncertainty involved in the calculation of PBR for some stocks. In a few prior incidental take rulemakings, this threshold was identified as the ‘‘significance threshold,’’ but it is more accurately labeled an insignificance threshold, and so we use that terminology here. Assuming that any additional incidental take by Level A or Level B harassment from the activities in question would not combine with the effects of the authorized M/SI to exceed the negligible impact level, the anticipated M/SI caused by the activities being evaluated would have a negligible impact on the species or stock. However, M/SI above the 10 percent insignificance threshold does not indicate that the M/SI associated with the specified activities is PO 00000 Frm 00102 Fmt 4701 Sfmt 4702 approaching a level that would necessarily exceed negligible impact. Rather, the 10 percent insignificance threshold is meant only to identify instances where additional analysis of the anticipated M/SI is not required because the negligible impact standard clearly will not be exceeded on that basis alone. Where the anticipated M/SI is near, at, or above residual PBR, consideration of other factors (positive or negative), including those outlined above, as well as mitigation is especially important to assessing whether the M/SI will have a negligible impact on the species or stock. PBR is a conservative metric and not sufficiently precise to serve as an absolute predictor of population effects upon which mortality caps would appropriately be based. For example, in some cases stock abundance (which is one of three key inputs into the PBR calculation) is underestimated because marine mammal survey data within the U.S. EEZ are used to calculate the abundance even when the stock range extends well beyond the U.S. EEZ. An underestimate of abundance could result in an underestimate of PBR. Alternatively, we sometimes may not have complete M/SI data beyond the U.S. EEZ to compare to PBR, which could result in an overestimate of residual PBR. The accuracy and certainty around the data that feed any PBR calculation, such as the abundance estimates, must be carefully considered to evaluate whether the calculated PBR accurately reflects the circumstances of the particular stock. M/SI that exceeds PBR may still potentially be found to be negligible in light of other factors that offset concern, especially when robust mitigation and adaptive management provisions are included. In Conservation Council for Hawaii v. National Marine Fisheries Service, which involved the challenge to NMFS’ issuance of LOAs to the Navy in 2013 for activities in the HSTT Study Area, the Court reached a different conclusion, stating, ‘‘Because any mortality level that exceeds PBR will not allow the stock to reach or maintain its OSP, such a mortality level could not be said to have only a ‘negligible impact’ on the stock.’’ As described above, the Court’s statement fundamentally misunderstands the two terms and incorrectly indicates that these concepts (PBR and ‘‘negligible impact’’) are directly connected, when in fact nowhere in the MMPA is it indicated that these two terms are equivalent. Specifically, PBR was designed as a tool for evaluating mortality and is defined as the number of animals that E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules can be removed while ‘‘allowing that stock to reach or maintain its [OSP].’’ OSP is defined as a population that falls within a range from the population level that is the largest supportable within the ecosystem to the population level that results in maximum net productivity, and thus is an aspirational management goal of the overall statute with no specific timeframe by which it should be met. PBR is designed to ensure minimal deviation from this overarching goal, with the formula for PBR typically ensuring that growth towards OSP is not reduced by more than 10 percent (or equilibrates to OSP 95 percent of the time). As PBR is applied by NMFS, it provides that growth toward OSP is not reduced by more than 10 percent, which certainly allows a stock to ‘‘reach or maintain its [OSP]’’ in a conservative and precautionary manner—and we can therefore clearly conclude that if PBR were not exceeded, there would not be adverse effects on the affected species or stocks. Nonetheless, it is equally clear that in some cases the time to reach this aspirational OSP level could be slowed by more than 10 percent (i.e., total human-caused mortality in excess of PBR could be allowed) without adversely affecting a species or stock through effects on its rates of recruitment or survival. Thus even in situations where the inputs to calculate PBR are thought to accurately represent factors such as the species’ or stock’s abundance or productivity rate, it is still possible for incidental take to have a negligible impact on the species or stock even where M/SI exceeds residual PBR or PBR. As noted above, in some cases the ongoing human-caused mortality from activities other than those being evaluated already exceeds PBR and, therefore, residual PBR is negative. In these cases (such as is specifically discussed for the CA/OR/WA stock of humpback whales below), any additional mortality, no matter how small, and no matter how small relative to the mortality caused by other human activities, would result in greater exceedance of PBR. PBR is helpful in informing the analysis of the effects of mortality on a species or stock because it is important from a biological perspective to be able to consider how the total mortality in a given year may affect the population. However, section 101(a)(5)(A) of the MMPA indicates that NMFS shall authorize the requested incidental take from a specified activity if we find that ‘‘the total of such taking [i.e., from the specified activity] will have a negligible impact on such species or stock.’’ In other words, the task under VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 the statute is to evaluate the applicant’s anticipated take in relation to their take’s impact on the species or stock, not other entities’ impacts on the species or stock. Neither the MMPA nor NMFS’ implementing regulations call for consideration of other unrelated activities and their impacts on the species or stock. In fact, in response to public comments on the implementing regulations NMFS explained that such effects are not considered in making negligible impact findings under section 101(a)(5), although the extent to which a species or stock is being impacted by other anthropogenic activities is not ignored. Such effects are reflected in the baseline of existing impacts as reflected in the species’ or stock’s abundance, distribution, reproductive rate, and other biological indicators. NMFS guidance for commercial fisheries provides insight when evaluating the effects of an applicant’s incidental take as compared to the incidental take caused by other entities. Parallel to section 101(a)(5)(A), section 101(a)(5)(E) of the MMPA provides that NMFS shall allow the incidental take of ESA-listed endangered or threatened marine mammals by commercial fisheries if, among other things, the incidental M/SI from the commercial fisheries will have a negligible impact on the species or stock. As discussed earlier, the authorization of incidental take resulting from commercial fisheries and authorization for activities other than commercial fisheries are under two separate regulatory frameworks. However, when it amended the statute in 1994 to provide a separate incidental take authorization process for commercial fisheries, Congress kept the requirement of a negligible impact determination for this one category of species, thereby applying the standard to both programs. Therefore, while the structure and other standards of the two programs differ such that evaluation of negligible impact under one program may not be fully applicable to the other program (e.g., the regulatory definition of ‘‘negligible impact’’ at 50 CFR 216.103 applies only to activities other than commercial fishing), guidance on determining negligible impact for commercial fishing take authorizations can be informative when considering incidental take outside the commercial fishing context. In 1999, NMFS published criteria for making a negligible impact determination pursuant to section 101(a)(5)(E) of the MMPA in a notice of proposed permits for certain fisheries (64 FR 28800; May 27, 1999). Criterion 2 stated if total human-related serious injuries and PO 00000 Frm 00103 Fmt 4701 Sfmt 4702 34015 mortalities are greater than PBR, and fisheries-related mortality is less than 0.1 PBR, individual fisheries may be permitted if management measures are being taken to address non-fisheriesrelated serious injuries and mortalities. When fisheries-related serious injury and mortality is less than 10 percent of the total, the appropriate management action is to address components that account for the major portion of the total. This criterion addresses when total human-caused mortality is exceeding PBR, but the activity being assessed is responsible for only a small portion of the mortality. The analytical framework we use here appropriately incorporates elements of the one developed for use under section 101(a)(5)(E) and because the negligible impact determination under section 101(a)(5)(A) focuses on the activity being evaluated, it is appropriate to utilize the parallel concept from the framework for section 101(a)(5)(E). Accordingly, we are using a similar criterion in our negligible impact analysis under section 101(a)(5)(A) to evaluate the relative role of an applicant’s incidental take when other sources of take are causing PBR to be exceeded, but the take of the specified activity is comparatively small. Where this occurs, we may find that the impacts of the taking from the specified activity may (those impacts alone, before we have considered the combined effects from any harassment take) be negligible even when total human-caused mortality from all activities exceeds PBR if (in the context of a particular species or stock): The authorized mortality or serious injury would be less than or equal to 10 percent of PBR and management measures are being taken to address serious injuries and mortalities from the other activities (i.e., other than the specified activities covered by the incidental take authorization under consideration). We must also determine, though, that impacts on the species or stock from other types of take (i.e., harassment) caused by the applicant do not combine with the impacts from mortality or serious injury to result in adverse effects on the species or stock through effects on annual rates of recruitment or survival. As discussed above, however, while PBR is useful in informing the evaluation of the effects of M/SI in section 101(a)(5)(A) determinations, it is just one consideration to be assessed in combination with other factors and is not determinative, including because, as explained above, the accuracy and certainty of the data used to calculate PBR for the species or stock must be E:\FR\FM\02JNP2.SGM 02JNP2 34016 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules considered. And we reiterate the considerations discussed above for why it is not appropriate to consider PBR an absolute cap in the application of this guidance. Accordingly, we use PBR as a trigger for concern while also considering other relevant factors to provide a reasonable and appropriate means of evaluating the effects of potential mortality on rates of recruitment and survival, while acknowledging that it is possible to exceed PBR (or exceed 10 percent of PBR in the case where other humancaused mortality is exceeding PBR but the specified activity being evaluated is an incremental contributor, as described in the last paragraph) by some small amount and still make a negligible impact determination under section 101(a)(5)(A). Our evaluation of the M/SI for each of the species and stocks for which mortality or serious injury could occur follows. No M/SI are anticipated from the Navy’s sonar activities or use of explosives. We first consider maximum potential incidental M/SI from the Navy’s ship strike analysis for the affected mysticetes and sperm whales (see Table 51) in consideration of NMFS’ threshold for identifying insignificant M/SI take. By considering the maximum potential incidental M/SI in relation to PBR and ongoing sources of anthropogenic mortality, we begin our evaluation of whether the potential incremental addition of M/SI through Navy’s ship strikes may affect the species’ or stocks’ annual rates of recruitment or survival. We also consider the interaction of those mortalities with incidental taking of that species or stock by harassment pursuant to the specified activity. Based on the methods discussed previously, NMFS believes that mortal takes of three large whales may occur over the course of the seven-year rule. Of the three total M/SI takes, the rule would authorize no more than two from any of the following species/stocks over the seven-year period: Fin whale (which may come from either the Northeast Pacific or CA/OR/WA stock) and humpback whale (which may come from either the Central North Pacific or CA/OR/WA stock). Of the three total M/ SI takes, the rule also would authorize no more than one mortality from any of the following species/stocks over the seven-year period: Sperm whale (CA/ OR/WA stock), minke whale (CA/OR/ WA stock), and gray whale (Eastern North Pacific stock). We do not anticipate, nor authorize, ship strike takes to blue whale (Eastern North Pacific stock), minke whale (Alaska stock), or sei whale (Eastern North Pacific stock). This means an annual average of 0.14 whales from each species or stock where one mortality may occur and an annual average of 0.29 whales from each species or stock where two mortalities may occur, as described in Table 51, is proposed for authorization (i.e., 1 or 2 takes over 7 years divided by 7 to get the annual number). TABLE 51—SUMMARY INFORMATION RELATED TO MORTALITIES REQUESTED FOR SHIP STRIKE, 2020–2027 Annual proposed NWTT authorized take by serious injury or mortality 1 Total annual M/SI * 2 Fisheries interactions (Y/N); annual rate of M/SI from fisheries interactions * Vessel collisions (Y/N); annual rate of M/SI from vessel collision * Annual Navy HSTT authorized take (2018– 2023) 5 Residual PBR-PBR minus annual M/SI and HSTT authorized take 3 Y; 0.4 0 5.1 4.7 ↑ ................................... N Y; 43 3.9 0.4 0.4 81 83 37.1 57.6 ↑ ................................... ↑ ................................... N N Recent UME (Y/N); number and year (since 2007) Species (stock) Stock abundance (Nbest) * Fin whale (Northeast Pacific). Fin whale (CA/OR/WA) Humpback whale (Central North Pacific). Humpback whale (CA/ OR/WA). Sperm whale (CA/OR/ WA). Minke whale (CA/OR/ WA). Gray whale (Eastern North Pacific). 3,168 .................................... 0.29 0.4 N; 0 9,029 .................................... 10,103 .................................. 0.29 0.29 ≥43.5 25 Y; ≥0.5 Y; 9.5 2,900 .................................... 0.29 ≥42.1 Y; ≥17.3 Y; 22 0.2 33.4 ¥8.9 Stable (↑ (historically) .. N 1,997 .................................... 0.14 0.4 Y; 0.4 N; 0 0 2.5 2.1 Unknown ...................... N 636 ....................................... 0.14 ≥1.3 Y; ≥1.3 N; 0 0 3.5 2.2 Unknown ...................... N 26,960 .................................. 0.14 139 Y; 9.6 Y; 0.8 0.4 801 661.6 ↑ ................................... Y, 264, 2019 6 Y; PBR * Stock trend *4 * Presented in the 2019 draft SARs or most recent SAR. 1 This column represents the annual take by serious injury or mortality by vessel collision and was calculated by the number of mortalities proposed for authorization divided by seven years (the length of the rule and LOAs). 2 This column represents the total number of incidents of M/SI that could potentially accrue to the specified species or stock. This number comes from the SAR, but deducts the takes accrued from either NMFS Science Center research activities or Navy strikes authorized for training and testing activities. No NMFS Science Center or Navy M/SI takes for these stocks are recorded in the SARs and no NMFS Science Center M/SI incidental takes have been authorized. 3 This value represents the calculated PBR minus the average annual estimate of ongoing anthropogenic mortalities (i.e., total annual human-caused M/SI column and the annual authorized take from the HSTT column). This value represents the total PBR for the stock in the stock’s entire range. 4 See relevant SARs for more information regarding stock status and trends. 5 This column represents annual M/SI take authorized through NMFS’ current 5-year HSTT regulations/LOAs (83 FR 66846). Note that NMFS has proposed to replace the current HSTT regulations with 7-year regulations (84 FR 48388) which propose to authorize the same number of M/SI for the same species/stocks, but over a 7-year period rather than a 5-year period (resulting in slightly lower annual authorized take for each species/stock). 6 This value represents average annual observed M/SI from ship strikes in Alaska (2.5) and Hawaii (1.4). For the purposes of analysis of potential ship strike (see the Estimated Takes section) we incorporated only Alaska ship strikes as only these ship strikes have the potential to overlap with the NWTT Study Area. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Stocks With M/SI Below the Insignificance Threshold As noted above, for a species or stock with incidental M/SI less than 10 percent of residual PBR, we consider M/ SI from the specified activities to represent an insignificant incremental increase in ongoing anthropogenic M/SI that alone (i.e., in the absence of any other take and barring any other unusual circumstances) will clearly not adversely affect annual rates of recruitment and survival. In this case, as VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 shown in Table 51, the following species or stocks have potential M/SI from ship strike proposed for authorization below their insignificance threshold: Fin whale (both the Northeast Pacific and CA/OR/WA stocks), humpback whale (Central North Pacific stock), sperm whale (CA/OR/WA stock), minke whale (CA/OR/WA stock), and gray whale (Eastern North Pacific stock). While the M/SI proposed for authorization of gray whales (Eastern North Pacific stock) is below the PO 00000 Frm 00104 Fmt 4701 Sfmt 4702 insignificance threshold, because of the recent UME, we further address how the authorized M/SI and the UME inform the negligible impact determination immediately below. For the other five stocks with M/SI proposed for authorization below the insignificance threshold, there are no other known factors, information, or unusual circumstances that indicate anticipated M/SI below the insignificance threshold could have adverse effects on annual rates of recruitment or survival and they E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules are not discussed further. For the remaining one stock (CA/OR/WA stock of humpback whales) with potential M/ SI above the insignificance threshold, how that M/SI compares to residual PBR, as well as additional factors, are discussed below as well. khammond on DSKJM1Z7X2PROD with PROPOSALS2 Gray Whales (Eastern North Pacific Stock) For this stock, PBR is currently set at 801. The total annual M/SI from other sources of anthropogenic mortality is estimated to be 139. In addition, 0.4 annual mortalities have been authorized for this same stock in the current incidental take regulations for Navy testing and training activities in the HSTT Study Area. This yields a residual PBR of 661.6. The additional 0.29 annual mortalities that are proposed for authorization in this rule are well below the insignificance threshold (10 percent of residual PBR, in this case 66.16). Nonetheless, since January 2019, gray whale strandings along the west coast of North America have been significantly higher than the previous 18-year average. Preliminary findings from necropsies have shown evidence of poor to thin body condition. The seasonal pattern of elevated strandings in the spring and summer months is similar to that of the previous gray whale UME in 1999–2000. Current total monthly strandings are slightly higher than 1999 and lower than 2000. If strandings continue to follow a similar pattern, we would anticipate a decrease in strandings in late summer and fall. However, combined with other annual human-caused mortalities, and viewed through the PBR lens (for human-caused mortalities), total human-caused mortality (inclusive of the potential for additional UME deaths) would still fall well below residual PBR and the insignificance threshold. Because of the abundance, population trend (increasing, despite the UME in 1999– 2000), and residual PBR (661.6) of this stock, this UME is not expected to have impacts on the population rate that, in combination with the effects of mortality proposed to be authorized, would affect annual rates of recruitment or survival. Stocks With M/SI Above the Insignificance Threshold Humpback Whale (CA/OR/WA Stock) For this stock, PBR is currently set at 16.7 for U.S. waters and 33.4 for the stock’s entire range. The total annual M/ SI is estimated at greater than or equal to 42.1. Combined with 0.2 annual mortalities that have been authorized for this same stock in the current incidental VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 take regulations for Navy testing and training activities in the HSTT Study Area, this yields a residual PBR of ¥8.9. NMFS proposes to authorize up to 2 M/ SI takes over the seven-year duration of this rule, which would be 0.29 M/SI takes annually for the purposes of comparing to PBR and considering other possible effects on annual rates of recruitment and survival. This means that with the additional 0.29 M/SI annual takes proposed in this rule, residual PBR would be exceeded by 9.19. In the commercial fisheries setting for ESA-listed marine mammals (which is similar to the non-fisheries incidental take setting, in that a negligible impact determination is required that is based on the assessment of take caused by the activity being analyzed) NMFS may find the impact of the authorized take from a specified activity to be negligible even if total human-caused mortality exceeds PBR, if the authorized mortality is less than 10 percent of PBR and management measures are being taken to address serious injuries and mortalities from the other activities causing mortality (i.e., other than the specified activities covered by the incidental take authorization under consideration). When those considerations are applied in the section 101(a)(5)(A) context here, the proposed authorized lethal take (0.29 annually) of humpback whales from the CA/OR/WA stock is significantly less than 10 percent of PBR (in fact less than 1 percent of 33.4) and there are management measures in place to address M/SI from activities other than those the Navy is conducting (as discussed below). Based on identical simulations as those conducted to identify Recovery Factors for PBR in Wade et al. (1998), but where values less than 0.1 were investigated (P. Wade, pers. comm.), we predict that where the mortality from a specified activity does not exceed Nmin * 1⁄2 Rmax * 0.013, the contemplated mortality for the specific activity will not delay the time to recovery by more than 1 percent. For this stock of humpback whales, Nmin * 1⁄2 Rmax * 0.013 = 1.45 and the annual mortality proposed for authorization is 0.29 (i.e., less than 1.45), which means that the mortality proposed to be authorized in this rule for NWTT activities would not delay the time to recovery by more than 1 percent. NMFS must also ensure that impacts by the applicant on the species or stock from other types of take (i.e., harassment) do not combine with the impacts from M/SI to adversely affect the species or stock via impacts on annual rates of recruitment or survival, PO 00000 Frm 00105 Fmt 4701 Sfmt 4702 34017 which is discussed further below in the species- and stock-specific section. In November 2019, NMFS published 2019 draft SARs in which PBR is reported as 33.4 with the predicted average annual mortality greater than or equal to 42.1 (including 22 estimated from vessel collisions and greater than 17.3 observed fisheries interactions). While the observed M/SI from vessel strikes remains low at 2.2 per year, the 2018 final and 2019 draft SARs rely on a new method to estimate annual deaths by ship strike utilizing an encounter theory model that combined species distribution models of whale density, vessel traffic characteristics, and whale movement patterns obtained from satellite-tagged animals in the region to estimate encounters that would result in mortality (Rockwood et al., 2017). The model predicts 22 annual mortalities of humpback whales from this stock from vessel strikes. The authors (Rockwood et al., 2017) do not suggest that ship strikes suddenly increased to 22. In fact, the model is not specific to a year, but rather offers a generalized prediction of ship strikes off the U.S. West Coast. Therefore, if the Rockwood et al. (2017) model is an accurate representation of vessel strike, then similar levels of ship strike have been occurring in past years as well. Put another way, if the model is correct, for some number of years total human-caused mortality has been significantly underestimated, and PBR has been similarly exceeded by a notable amount, and yet the CA/OR/WA stock of humpback whales is considered stable (or increasing based on population trends since 1990) nevertheless. The CA/OR/WA stock of humpback whales experienced a steady increase from the 1990s through approximately 2008, and more recent estimates through 2014 indicate a leveling off of the population size. This stock is comprised of the feeding groups of three DPSs. Two DPSs associated with this stock are listed under the ESA as either endangered (Central America DPS) or threatened (Mexico DPS), while the third (Hawaii DPS) is not listed. Humpback whales from the Hawaii DPS are anticipated to be rare in the Study Area with a probability of the DPS foraging in the waters of the Study Area of 1.6 percent (including summer areas of Oregon/California and Southern British Columbia/Washington from Wade, 2017). Humpback whales from the Mexico DPS and Central America DPS are anticipated to be more prevalent in the Study Area with probabilities of the DPSs foraging in the waters of the Study Area of 31.7 and 100 percent, respectively (including summer E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 34018 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules areas of Oregon/California and Southern British Columbia/Washington from Wade, 2017). As discussed earlier, we also take into consideration management measures in place to address M/SI caused by other activities. The California swordfish and thresher shark drift gillnet fishery is one of the primary causes of M/SI take from fisheries interactions for humpback whales on the West Coast. NMFS established the Pacific Offshore Cetacean Take Reduction Team in 1996 and prepared an associated Plan (POCTRP) to reduce the risk of M/SI via fisheries interactions. In 1997, NMFS published final regulations formalizing the requirements of the PCTRP, including the use of pingers following several specific provisions and the employment of Skipper education workshops. Commercial fisheries such as crab pot, gillnet, and prawn fisheries are also a significant source of mortality and serious injury for humpback whales and other large whales and, unfortunately, have increased mortalities and serious injuries over recent years (Carretta et al., 2019). However, the 2019 draft SAR notes that a recent increase in disentanglement efforts has resulted in an increase in the fraction of cases that are reported as non-serious injuries as a result of successful disentanglement. More importantly, since 2015, NMFS has engaged in a multi-stakeholder process in California (including California State resource managers, fishermen, non-governmental organizations (NGOs), and scientists) to identify and develop solutions and make recommendations to regulators and the fishing industry for reducing whale entanglements (see https:// www.opc.ca.gov/whale-entanglementworking-group/), referred to as the Whale Entanglement Working Group. The Whale Entanglement Working Group has made significant progress since 2015 and is tackling the problem from multiple angles, including: • Development of Fact Sheets and Best Practices for specific Fisheries issues (e.g., California Dungeness Crab Fishing BMPs and the 2018–2019 Best Fishing Practices Guide); • 2018–2019 Risk Assessment and Mitigation Program (RAMP) to support the state of California in working collaboratively with experts (fishermen, researchers, NGOs, etc.) to identify and assess elevated levels of entanglement risk and determine the need for management options to reduce risk of entanglement; and • Support of pilot studies to test new fisheries technologies to reduce take (e.g., Exploring Ropeless Fishing VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Technologies for the California Dungeness Crab Fishery). The Working Group meets regularly, posts reports and annual recommendations, and makes all of their products and guidance documents readily accessible for the public. The March 2019 Working Group Report reported on the status of the fishery closure, progress and continued development of the RAMP (though there is a separate RAMP report), discussed the role of the Working Group (development of a new Charter), and indicated next steps. Importantly, in early 2019, as a result of a litigation settlement agreement, the California Department of Fish and Wildlife (CDFW) closed the Dungeness crab fishery three months early for the year, which is expected to reduce the number of likely entanglements. The agreement also limits the fishery duration over the next couple of years and has different triggers to reduce or close it further. Further, pursuant to the settlement, CDFW is required to apply for a Section 10 Incidental Take Permit under the ESA to address protected species interactions with fishing gear and crab fishing gear (pots), and they have agreed to prepare a Conservation Plan by May 2020. Any request for such a permit must include a Conservation Plan that specifies, among other things, what steps the applicant will take to minimize and mitigate the impacts, and the funding that will be available to implement such steps. Regarding measures in place to reduce mortality from other sources, the Channel Islands NMS staff coordinates, collects, and monitors whale sightings in and around a Whale Advisory Zone and the Channel Islands NMS region, which is within the area of highest vessel strike mortality (90th percentile) for humpback whales on the U.S. West Coast (Rockwood et al., 2017). The seasonally established Whale Advisory Zone spans from Point Arguello to Dana Point, including the Traffic Separation Schemes in the Santa Barbara Channel and San Pedro Channel. Vessels transiting the area from June through November are recommended to exercise caution and voluntarily reduce speed to 10 kn or less for blue, humpback, and fin whales. Channel Island NMS observers collect information from aerial surveys conducted by NOAA, the U.S. Coast Guard, California Department of Fish and Game, and Navy chartered aircraft. Information on seasonal presence, movement, and general distribution patterns of large whales is shared with mariners, NMFS’ Office of Protected Resources, the U.S. Coast Guard, the California Department of PO 00000 Frm 00106 Fmt 4701 Sfmt 4702 Fish and Game, the Santa Barbara Museum of Natural History, the Marine Exchange of Southern California, and whale scientists. Real time and historical whale observation data collected from multiple sources can be viewed on the Point Blue Whale Database. More recently, similar efforts to reduce entanglement risk and severity have also been initiated in Oregon and Washington. Both Oregon and Washington are developing applications for ESA Incidental Take Permits for their commercial crab fisheries. They advocate similar best practices for their fishermen as California, and they are taking regulatory steps related to gear marking and pot limits. In this case, 0.29 M/SI annually means the potential for two mortalities in one or two of the seven years and zero mortalities in five or six of those seven years. Therefore, the Navy would not be contributing to the total humancaused mortality at all in at least five of the seven, or 71.4 percent, of the years covered by this rule. That means that even if a humpback whale from the CA/ OR/WA stock were to be struck, in at least five of the seven years there could be no effect on annual rates of recruitment or survival from Navycaused M/SI. Additionally, the loss of a male would have far less, if any, of an effect on population rates than the loss of a reproductive female (as males are known to mate with multiple females), and absent any information suggesting that one sex is more likely to be struck than another, we can reasonably assume that there is a 50 percent chance that the strikes proposed to be authorized by this rule would be males, thereby further decreasing the likelihood of impacts on the population rate. In situations like this where potential M/SI is fractional, consideration must be given to the lessened impacts anticipated due to the absence of any M/SI in five or six of the years and due to the fact that strikes could be males. Lastly, we reiterate that PBR is a conservative metric and also not sufficiently precise to serve as an absolute predictor of population effects upon which mortality caps would appropriately be based. Wade et al. (1998), authors of the paper from which the current PBR equation is derived, note that ‘‘Estimating incidental mortality in one year to be greater than the PBR calculated from a single abundance survey does not prove the mortality will lead to depletion; it identifies a population worthy of careful future monitoring and possibly indicates that mortality-mitigation efforts should be initiated.’’ E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 The information included here illustrates that this humpback whale stock is stable, the potential (and proposed authorized) mortality is well below 10 percent (0.87 percent) of PBR, and management actions are in place to minimize both fisheries interactions and ship strike from other vessel activity in one of the highest-risk areas for strikes. More specifically, although the total human-mortality exceeds PBR, the authorized mortality proposed for the Navy’s specified activities would incrementally contribute less than 1 percent of that and, further, given the fact that it would occur in only one or two of the seven years with a 50 percent chance of the take involving males (far less impactful to the population), the potential impacts on population rates are even less. Based on all of the considerations described above, including consideration of the fact that the M/SI of 0.29 proposed for authorization would not delay the time to recovery by more than 1 percent, we do not expect the potential lethal take from Navy activities, alone, to adversely affect the CA/OR/WA stock of humpback whales through effects on annual rates of recruitment or survival. Nonetheless, the fact that total humancaused mortality exceeds PBR necessitates close attention to the remainder of the impacts (i.e., harassment) on the CA/OR/WA stock of humpback whales from the Navy’s activities to ensure that the total authorized takes would have a negligible impact on the species and stock. Therefore, this information will be considered in combination with our assessment of the impacts of authorized harassment takes in the Group and Species-Specific Analyses section that follows. Group and Species-Specific Analyses The maximum amount and type of incidental take of marine mammals reasonably likely to occur and therefore proposed to be authorized from exposures to sonar and other active acoustic sources and explosions during the seven-year training and testing period are shown in Tables 32 and 33 along with the discussion in the Estimated Take of Marine Mammals section on Vessel Strike. The vast majority of predicted exposures (greater than 99 percent) are expected to be Level B harassment (non-injurious TTS and behavioral reactions) from acoustic and explosive sources during training and testing activities at relatively low received levels. In the discussions below, the estimated Level B harassment takes represent instances of take, not the VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 number of individuals taken (the much lower and less frequent Level A harassment takes are far more likely to be associated with separate individuals), and in some cases individuals may be taken more than one time. Below, we compare the total take numbers (including PTS, TTS, and behavioral disruption) for species or stocks to their associated abundance estimates to evaluate the magnitude of impacts across the species and to individuals. Specifically, when an abundance percentage comparison is below 100, it means that that percentage or less of the individuals will be affected (i.e., some individuals will not be taken at all), that the average for those taken is one day per year, and that we would not expect any individuals to be taken more than a few times in a year. When it is more than 100 percent, it means there will definitely be some number of repeated takes of individuals. For example, if the percentage is 300, the average would be each individual is taken on three days in a year if all were taken, but it is more likely that some number of individuals will be taken more than three times and some number of individuals fewer or not at all. While it is not possible to know the maximum number of days across which individuals of a stock might be taken, in acknowledgement of the fact that it is more than the average, for the purposes of this analysis, we assume a number approaching twice the average. For example, if the percentage of take compared to the abundance is 800, we estimate that some individuals might be taken as many as 16 times. Those comparisons are included in the sections below. To assist in understanding what this analysis means, we clarify a few issues related to estimated takes and the analysis here. An individual that incurs a PTS or TTS take may sometimes, for example, also be subject to behavioral disturbance at the same time. As described above in this section, the degree of PTS, and the degree and duration of TTS, expected to be incurred from the Navy’s activities are not expected to impact marine mammals such that their reproduction or survival could be affected. Similarly, data do not suggest that a single instance in which an animal accrues PTS or TTS and is also subjected to behavioral disturbance would result in impacts to reproduction or survival. Alternately, we recognize that if an individual is subjected to behavioral disturbance repeatedly for a longer duration and on consecutive days, effects could accrue to the point that reproductive success is jeopardized, PO 00000 Frm 00107 Fmt 4701 Sfmt 4702 34019 although those sorts of impacts are generally not expected to result from these activities. Accordingly, in analyzing the number of takes and the likelihood of repeated and sequential takes, we consider the total takes, not just the Level B harassment takes by behavioral disruption, so that individuals potentially exposed to both threshold shift and behavioral disruption are appropriately considered. The number of Level A harassment takes by PTS are so low (and zero in most cases) compared to abundance numbers that it is considered highly unlikely that any individual would be taken at those levels more than once. Use of sonar and other transducers would typically be transient and temporary. The majority of acoustic effects to marine mammals from sonar and other active sound sources during testing and training activities would be primarily from ASW events. It is important to note that unlike other Navy Training and Testing Study Areas, there are no MTEs proposed for the NWTT Study Area. On the less severe end, exposure to comparatively lower levels of sound at a detectably greater distance from the animal, for a few or several minutes, could result in a behavioral response such as avoiding an area that an animal would otherwise have moved through or fed in, or breaking off one or a few feeding bouts. More severe behavioral effects could occur when an animal gets close enough to the source to receive a comparatively higher level of sound, is exposed continuously to one source for a longer time, or is exposed intermittently to different sources throughout a day. Such effects might result in an animal having a more severe flight response and leaving a larger area for a day or more, or potentially losing feeding opportunities for a day. However, such severe behavioral effects are expected to occur infrequently. Occasional, milder behavioral reactions are unlikely to cause long-term consequences for individual animals or populations, and even if some smaller subset of the takes are in the form of a longer (several hours or a day) and more severe response, if they are not expected to be repeated over sequential days, impacts to individual fitness are not anticipated. Nearly all studies and experts agree that infrequent exposures of a single day or less are unlikely to impact an individual’s overall energy budget (Farmer et al., 2018; Harris et al., 2017; King et al., 2015; NAS 2017; New et al., 2014; Southall et al., 2007; Villegas-Amtmann et al., 2015). When impacts to individuals increase in magnitude or severity such that either E:\FR\FM\02JNP2.SGM 02JNP2 34020 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 repeated and sequential higher severity impacts occur (the probability of this goes up for an individual the higher total number of takes it has) or the total number of moderate to more severe impacts increases substantially, especially if occurring across sequential days, then it becomes more likely that the aggregate effects could potentially interfere with feeding enough to reduce energy budgets in a manner that could impact reproductive success via longer cow-calf intervals, terminated pregnancies, or calf mortality. It is important to note that these impacts only accrue to females, which only comprise a portion of the population (typically approximately 50 percent). Based on energetic models, it takes energetic impacts of a significantly greater magnitude to cause the death of an adult marine mammal, and females will always terminate a pregnancy or stop lactating before allowing their health to deteriorate. Also, as noted previously, the death of an adult female has significantly more impact on population growth rates than reductions in reproductive success, while the death of an adult male has very little effect on population growth rates. However, as explained earlier, such severe impacts from the Navy’s activities would be very infrequent and not likely to occur at all for most species and stocks. Even for those species or stocks where it is possible for a small number of females to experience reproductive effects, we explain below why there still would be VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 no effect on rates of recruitment or survival. The analyses below in some cases address species collectively if they occupy the same functional hearing group (i.e., low, mid, and highfrequency cetaceans), share similar life history strategies, and/or are known to behaviorally respond similarly to acoustic stressors. Because some of these groups or species share characteristics that inform the impact analysis similarly, it would be duplicative to repeat the same analysis for each species. In addition, similar species typically have the same hearing capabilities and behaviorally respond in the same manner. Thus, our analysis below considers the effects of the Navy’s activities on each affected species or stock even where discussion is organized by functional hearing group and/or information is evaluated at the group level. Where there are meaningful differences between a species or stock that would further differentiate the analysis, they are either described within the section or the discussion for those species or stocks is included as a separate subsection. Specifically below, we first give broad descriptions of the mysticete, odontocete, and pinniped groups and then differentiate into further groups as appropriate. Mysticetes This section builds on the broader discussion above and brings together the discussion of the different types and PO 00000 Frm 00108 Fmt 4701 Sfmt 4702 amounts of take that different species and stocks could potentially or would likely incur, the applicable mitigation, and the status of the species and stocks to support the preliminary negligible impact determinations for each species or stock. We have described (earlier in this section) the unlikelihood of any masking having effects that would impact the reproduction or survival of any of the individual marine mammals affected by the Navy’s activities. We have also described above in the Potential Effects of Specified Activities on Marine Mammals and their Habitat section the unlikelihood of any habitat impacts having effects that would impact the reproduction or survival of any of the individual marine mammals affected by the Navy’s activities. For mysticetes, there is no predicted PTS from sonar or explosives and no predicted tissue damage from explosives for any species. Much of the discussion below focuses on the behavioral effects and the mitigation measures that reduce the probability or severity of effects. Because there are species-specific and stock-specific considerations as well as M/SI take proposed for several stocks, at the end of the section we break out our findings on a species-specific and, for one species, stock-specific basis. In Table 52 below for mysticetes, we indicate for each species and stock the total annual numbers of take by mortality, Level A and Level B harassment, and a number indicating the instances of total take as a percentage of abundance. E:\FR\FM\02JNP2.SGM 02JNP2 The majority of takes by harassment of mysticetes in the NWTT Study Area are caused by anti-submarine warfare (ASW) activities in the Offshore portion of the Study Area. Anti-submarine activities include sources from the MFAS bin (which includes hullmounted sonar) because they are high level, narrowband sources in the 1–10 kHz range, which intersect what is estimated to be the most sensitive area of hearing for mysticetes. They also are used in a large portion of exercises (see Tables 3 and 4). Most of the takes (90 percent) from the MF1 bin in the NWTT Study Area would result from received levels between 160 and 178 dB SPL, while another 9 percent would result from exposure between 178 and 184 dB SPL. For the remaining active sonar bin types, the percentages are as follows: LF4 = 97 percent between 124 and 142 dB SPL, MF4 = 95 percent between 136 and 148 dB SPL, MF5 = 97 percent between 112 and 142 dB SPL, and HF4 = 91 percent between 100 and 154 dB SPL. For mysticetes, explosive training activities do not result in any take. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Explosive testing activities result in a small number of behavioral Level B harassment takes (0–6 per stock) and TTS takes (0–2 per stock). Based on this information, the majority of the Level B behavioral harassment is expected to be of low to sometimes moderate severity and of a relatively shorter duration. No PTS or tissue damage from training and testing activities is anticipated or proposed for authorization for any species or stock. Research and observations show that if mysticetes are exposed to sonar or other active acoustic sources they may react in a number of ways depending on the characteristics of the sound source, their experience with the sound source, and whether they are migrating or on seasonal feeding or breeding grounds. Behavioral reactions may include alerting, breaking off feeding dives and surfacing, diving or swimming away, or no response at all (DOD, 2017; Nowacek, 2007; Richardson, 1995; Southall et al., 2007). Overall, mysticetes have been observed to be more reactive to acoustic disturbance PO 00000 Frm 00109 Fmt 4701 Sfmt 4702 34021 when a noise source is located directly on their migration route. Mysticetes disturbed while migrating could pause their migration or route around the disturbance, while males en route to breeding grounds have been shown to be less responsive to disturbances. Although some may pause temporarily, they will resume migration shortly after the exposure ends. Animals disturbed while engaged in other activities such as feeding or reproductive behaviors may be more likely to ignore or tolerate the disturbance and continue their natural behavior patterns. Alternately, adult females with calves may be more responsive to stressors. As noted in the Potential Effects of Specified Activities on Marine Mammals and Their Habitat section, there are multiple examples from behavioral response studies of odontocetes ceasing their feeding dives when exposed to sonar pulses at certain levels, but alternately, blue whales were less likely to show a visible response to sonar exposures at certain levels when feeding than when traveling. However, Goldbogen et al. (2013) indicated some E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.008</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 34022 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules horizontal displacement of deep foraging blue whales in response to simulated MFAS. Southall et al. (2019b) observed that after exposure to simulated and operational midfrequency active sonar, more than 50 percent of blue whales in deep-diving states responded to the sonar, while no behavioral response was observed in shallow-feeding blue whales. Southall et al. (2019b) noted that the behavioral responses they observed were generally brief, of low to moderate severity, and highly dependent on exposure context (behavioral state, source-to-whale horizontal range, and prey availability). Most Level B behavioral harassment of mysticetes is likely to be short-term and of low to sometimes moderate severity, with no anticipated effect on reproduction or survival. Richardson et al. (1995) noted that avoidance (temporary displacement of an individual from an area) reactions are the most obvious manifestations of disturbance in marine mammals. Avoidance is qualitatively different from the startle or flight response, but also differs in the magnitude of the response (i.e., directed movement, rate of travel, etc.). Oftentimes avoidance is temporary, and animals return to the area once the noise has ceased. Some mysticetes may avoid larger activities as they move through an area, although the Navy’s activities do not typically use the same training locations day-after-day during multi-day activities, except periodically in instrumented ranges. Therefore, displaced animals could return quickly after even a large activity is completed. In the ocean, the use of Navy sonar and other active acoustic sources is transient and is unlikely to expose the same population of animals repeatedly over a short period of time, especially given the broader-scale movements of mysticetes. The implementation of procedural mitigation and the sightability of mysticetes (due to their large size) further reduces the potential for a significant behavioral reaction or a threshold shift to occur (i.e., shutdowns are expected to be successfully implemented), which is reflected in the amount and type of incidental take that is anticipated to occur and proposed for authorization. As noted previously, when an animal incurs a threshold shift, it occurs in the frequency from that of the source up to one octave above. This means that the vast majority of threshold shifts caused by Navy sonar sources will typically occur in the range of 2–20 kHz (from the 1–10 kHz MF bin, though in a specific narrow band within this range as the sources are narrowband), and if VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 resulting from hull-mounted sonar, will be in the range of 3.5–7 kHz. The majority of mysticete vocalizations occur in frequencies below 1 kHz, which means that TTS incurred by mysticetes will not interfere with conspecific communication. Additionally, many of the other critical sounds that serve as cues for navigation and prey (e.g., waves, fish, invertebrates) occur below a few kHz, which means that detection of these signals will not be inhibited by most threshold shift either. When we look in ocean areas where the Navy has been intensively training and testing with sonar and other active acoustic sources for decades, there is no data suggesting any long-term consequences to reproduction or survival rates of mysticetes from exposure to sonar and other active acoustic sources. All the mysticete species discussed in this section would benefit from the procedural mitigation measures described earlier in the Proposed Mitigation Measures section. Additionally, the Navy would limit activities and employ other measures in mitigation areas that would avoid or reduce impacts to mysticetes. Where these mitigation areas are designed to mitigate impacts to particular species or stocks (gray whales and humpback whales), they are discussed in detail below. Below we compile and summarize the information that supports our preliminary determination that the Navy’s activities would not adversely affect any species or stock through effects on annual rates of recruitment or survival for any of the affected mysticete stocks. Blue Whale (Eastern North Pacific Stock) Blue whales are listed as endangered under the ESA throughout their range, but there is no ESA designated critical habitat or biologically important areas identified for this species in the NWTT Study Area. The SAR identifies this stock as ‘‘stable’’. We further note that this stock was originally listed under the ESA as a result of the impacts from commercial whaling, which is no longer affecting the species. Blue whales are anticipated to be present in summer and winter months and only in the Offshore Area of the Study Area. No mortality from either explosives or vessel strike and no Level A harassment is anticipated or proposed for authorization. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is less than 1 percent. Given PO 00000 Frm 00110 Fmt 4701 Sfmt 4702 the range of blue whales, this information indicates that only a very small portion of individuals in the stock are likely impacted and repeated exposures of individuals are not anticipated. Regarding the severity of those individual takes by behavioral Level B harassment, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB with a small portion up to 184 dB (i.e., of a moderate or lower level, less likely to evoke a severe response). Regarding the severity of TTS takes, we have explained that they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with blue whale communication or other important low-frequency cues and that the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, this population is stable, only a very small portion of the stock is anticipated to be impacted, and any individual blue whale is likely to be disturbed at a low-moderate level. No mortality and no Level A harassment is anticipated or proposed for authorization. The low magnitude and severity of harassment effects is not expected to result in impacts on the reproduction or survival of any individuals, let alone have impacts on annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the Eastern North Pacific stock of blue whales. Fin Whale (Northeast Pacific Stock and California/Oregon/Washington Stock) Fin whales are listed as endangered under the ESA throughout their range, but no ESA designated critical habitat or biologically important areas are identified for this species in the NWTT Study Area. The SAR identifies these stocks as ‘‘increasing.’’ NMFS is proposing to authorize two mortalities of fin whales over the seven years covered by this rule, but because it is not possible to determine from which stock these potential takes would occur, that is 0.29 mortality annually for each stock. The addition of this 0.29 annual mortality still leaves the total annual human-caused mortality well under residual PBR (37.1 for the CA/OR/WA stock and 4.7 for the Northeast Pacific stock) and below the insignificance threshold for both stocks. No mortality from explosives and no Level A E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 harassment is anticipated or proposed for authorization. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is less than 1 percent for the Northeast Pacific stock and 1.5 percent for the CA/OR/WA stock. This information indicates that only a very small portion of individuals in each stock are likely impacted and repeated exposures of individuals are not anticipated. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB with a small portion up to 184 dB (i.e., of a moderate or lower level, less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with fin whale communication or other important lowfrequency cues—and the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, these populations are increasing, only a small portion of each stock is anticipated to be impacted, and any individual fin whale is likely to be disturbed at a low-moderate level. No Level A harassment is anticipated or proposed to be authorized. This low magnitude and severity of harassment effects is not expected to result in impacts on individual reproduction or survival for any individuals, nor are these harassment takes combined with the proposed authorized mortality expected to adversely affect these stocks through impacts on annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on both the Northeast Pacific and CA/OR/ WA stocks of fin whales. Humpback Whale (Central North Pacific Stock) The Central North Pacific stock of humpback whales consists of winter/ spring humpback whale populations of the Hawaiian Islands which migrate primarily to foraging habitat in northern British Columbia/Southeast Alaska, the Gulf of Alaska, and the Bering Sea/ Aleutian Islands (Muto et al. 2019). Three Feeding Area biologically important areas for humpback whales VerDate Sep<11>2014 23:01 Jun 01, 2020 Jkt 250001 overlap with the NWTT Study Area: Northern Washington Feeding Area for humpback whales (May–November); Stonewall and Heceta Bank Feeding Area for humpback whales (May– November); and Point St. George Feeding Area for humpback whales (July–November) (Calambokidis et al., 2015). The Marine Species Coastal, Olympic Coast National Marine Sanctuary, Stonewall and Hecta Bank Humpback Whale, and Point St. George Humpback Whale Mitigation Areas overlap with these important foraging areas. The mitigation measures implemented in each of these areas including no MF1 MFAS use seasonally or limited MFAS use year round, no explosive training, etc. (see details for each area in the Proposed Mitigation section), would reduce the severity of impacts to humpback whales by reducing interference in feeding that could result in lost feeding opportunities or necessitate additional energy expenditure to find other good opportunities. The SAR identifies this stock as ‘‘increasing’’ and the associated Hawaii DPS is not listed under the ESA. No mortality from explosives and no Level A harassment is anticipated or proposed for authorization. NMFS proposes to authorize two mortalities of humpback whales over the seven years covered by this rule, but because it is not possible to determine from which stock these potential takes would occur, that is 0.29 mortality annually for both this stock and the CA/OR/WA stock (discussed separately below). The addition of this 0.29 annual mortality still leaves the total annual human-caused mortality well under both the insignificance threshold and residual PBR (57.6). Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated instances of take compared to the abundance is 1 percent. This information and the complicated farranging nature of the stock structure indicates that only a very small portion of the stock is likely impacted and repeated exposures of individuals are not anticipated. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB with a small portion up to 184 dB (i.e., of a moderate or lower level, less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected PO 00000 Frm 00111 Fmt 4701 Sfmt 4702 34023 to interfere with humpback whale communication or other important lowfrequency cues, and that the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, this population is increasing and the associated DPS is not listed as endangered or threatened under the ESA. Only a very small portion of the stock is anticipated to be impacted and any individual humpback whale is likely to be disturbed at a lowmoderate level. No Level A harassment is anticipated or proposed to be authorized. This low magnitude and severity of harassment effects is not expected to result in impacts on individual reproduction or survival, nor are these harassment takes combined with the proposed authorized mortality expected to adversely affect this stock through effects on annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the Central North Pacific stock of humpback whales. Humpback Whale (California/Oregon/ Washington Stock) The CA/OR/WA stock of humpback whales includes individuals from three ESA DPSs: Central America (endangered), Mexico (threatened), and Hawaii (not listed). There is no ESAdesignated critical habitat for humpback whales, however NMFS recently proposed to designate critical habitat for humpback whales (84 FR 54354; October 9, 2019). Three Feeding Area biologically important areas for humpback whales overlap with the NWTT Study Area: Northern Washington Feeding Area for humpback whales (May–November); Stonewall and Heceta Bank Feeding Area for humpback whales (May–November); and Point St. George Feeding Area for humpback whales (July–November) (Calambokidis et al., 2015). The Marine Species Coastal, Olympic Coast National Marine Sanctuary, Stonewall and Hecta Bank Humpback Whale, and Point St. George Humpback Whale Mitigation Areas overlap with these important foraging areas. The mitigation measures implemented in each of these areas including no MF1 MFAS use seasonally or limited MFAS use year round, no explosive training, etc. (see details for each area in the Proposed Mitigation section), would reduce the severity of impacts to humpback whales by reducing interference in feeding that could result in lost feeding E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 34024 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules opportunities or necessitate additional energy expenditure to find other good opportunities. The SAR identifies this stock as stable (having shown a long-term increase from 1990 and then leveling off between 2008 and 2014). NMFS proposes to authorize two mortalities over the seven years covered by this rule, or 0.29 mortality annually. With the addition of this 0.29 annual mortality, the total annual human-caused mortality exceeds residual PBR by 9.19. However, as described in more detail in the Serious Injury or Mortality section, when total human-caused mortality exceeds PBR, we consider whether the incremental addition of a small amount of mortality proposed for authorization from the specified activity may still result in a negligible impact, in part by identifying whether it is less than 10 percent of PBR. In this case, the mortality proposed for authorization is well below 10 percent of PBR (less than one percent, in fact) and management measures are in place to reduce mortality from other sources. More importantly, as described above in the Serious Injury or Mortality section, the mortality of 0.29 proposed for authorization would not delay the time to recovery by more than 1 percent. Given these considerations, the incremental addition of two mortalities over the course of the seven-year Navy rule is not expected to, alone, lead to adverse impacts on the stock through effects on annual rates of recruitment or survival. No mortality from explosives and no Level A harassment is anticipated or proposed for authorization. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is 3 percent. Given the range of humpback whales, this information indicates that only a very small portion of individuals in the stock are likely impacted and repeated exposures of individuals are not anticipated. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB with a small portion up to 184 dB (i.e., of a moderate or lower level, less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with humpback whale communication or other important low- VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 frequency cues and the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, this population is stable (even though two of the three associated DPSs are listed as endangered or threatened under the ESA), only a small portion of the stock is anticipated to be impacted, and any individual humpback whale is likely to be disturbed at a low-moderate level. No Level A harassment is anticipated or proposed to be authorized. This low magnitude and severity of harassment effects is not expected to result in impacts on the reproduction or survival of any individuals and, therefore, when combined with the proposed authorized mortality (which our earlier analysis indicated will not, alone, have more than a negligible impact on this stock of humpback whales), the total take is not expected to adversely affect this stock through impacts on annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the CA/OR/WA stock of humpback whales. Minke Whale (Alaska and California/ Oregon/Washington Stocks) The status of these stocks is unknown and the species is not listed under the ESA. No biologically important areas have been identified for this species in the NWTT Study Area. NMFS proposes to authorize one mortality over the seven years covered by this rule, or 0.14 mortality annually. The addition of this 0.14 annual mortality still leaves the total annual human-caused mortality well under the residual PBR (2.2) and below the insignificance threshold. No mortality from explosives and no Level A harassment is anticipated or proposed for authorization. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is less than 1 percent for the Alaska stock (based on, to be conservative, the smallest available provisional estimate in the SAR, which is derived from surveys that cover only a portion of the stock’s range) and 47.5 percent for the CA/OR/WA stock. Given the range of minke whales, this information indicates that only a portion of individuals in these stocks are likely to be impacted and repeated exposures of individuals are not anticipated. Regarding the severity of those individual Level B harassment PO 00000 Frm 00112 Fmt 4701 Sfmt 4702 takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB with a small portion up to 184 dB (i.e., of a moderate or lower level, less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with minke whale communication or other important lowfrequency cues—and the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, although the status of the stocks is unknown, the species is not listed under the ESA as endangered or threatened, only a portion of these stocks is anticipated to be impacted, and any individual minke whale is likely to be disturbed at a low-moderate level. No Level A harassment is anticipated or proposed to be authorized. This low magnitude and severity of harassment effects is not expected to result in impacts on individual reproduction or survival, nor are these harassment takes combined with the proposed authorized mortality expected to adversely affect these stocks through effects on annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the Alaska and CA/OR/WA stocks of minke whales. Sei Whale (Eastern North Pacific Stock) The status of this stock is unknown, however sei whales are listed as endangered under the ESA throughout their range. There is no ESA designated critical habitat or biologically important areas identified for this species in the NWTT Study Area. No mortality from either explosives or vessel strikes and no Level A harassment is anticipated or proposed for authorization. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is 16 percent. This information and the large range of sei whales suggests that only a small portion of individuals in the stock are likely impacted and repeated exposures of individuals are not anticipated. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB with a small portion up to 184 dB (i.e., of a moderate or lower level, less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with sei whale communication or other important lowfrequency cues and the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, the status of the stock is unknown and the species is listed as endangered, but only a small portion of the stock is anticipated to be impacted and any individual sei whale is likely to be disturbed at a low-moderate level. No mortality and no Level A harassment is anticipated or proposed for authorization. This low magnitude and severity of harassment effects is not expected to result in impacts on individual reproduction or survival, much less annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the Eastern North Pacific stock of sei whales. Gray Whale (Eastern North Pacific Stock) The SAR identifies this stock as ‘‘increasing’’ and the associated DPS is not listed under the ESA. The NWTT Study Area overlaps with the offshore Northwest Washington and the Northern Puget Sound gray whale Feeding biologically important areas, and a portion of the Northwest coast of Washington approximately from Pacific Beach (WA) and extending north to the Strait of Juan de Fuca overlaps with the gray whale Migrations Corridor biologically important area. The Marine Species Coastal, Olympic Coast National Marine Sanctuary, Stonewall and Hecta Bank Humpback Whale, and Point St. George Humpback Whale, and Northern Puget Sound Gray Whale Mitigation Areas overlap with these important foraging and migration areas. The mitigation measures implemented in each of these areas including no MF1 MFAS use seasonally or limited MFAS use year round, no explosive training, etc. (see details for each area in the Proposed Mitigation section), would reduce the severity of impacts to gray whales by reducing interference in feeding and migration that could result in lost feeding opportunities or necessitate additional energy VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 expenditure to find other good foraging opportunities or move migration routes. NMFS proposes to authorize one mortality over the seven years covered by this rule, or 0.14 mortality annually. The addition of this 0.14 annual mortality still leaves the total annual human-caused mortality well under both the insignificance threshold and residual PBR (661.6). No mortality from explosives and no Level A harassment is anticipated or proposed for authorization. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is less than 1 percent. This information indicates that only a very small portion of individuals in the stock are likely to be impacted and repeated exposures of individuals are not anticipated. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB with a small portion up to 184 dB (i.e., of a moderate or lower level, less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with gray whale communication or other important lowfrequency cues and that the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, while we have considered the impacts of the gray whale UME, this population of gray whales is not endangered or threatened under the ESA and the stock is increasing. No Level A harassment is anticipated or proposed to be authorized. Only a very small portion of the stock is anticipated to be impacted by Level B harassment and any individual gray whale is likely to be disturbed at a low-moderate level. This low magnitude and severity of harassment effects is not expected to result in impacts to reproduction or survival for any individuals, nor are these harassment takes combined with the proposed authorized mortality of one whale over the seven-year period expected to adversely affect this stock through impacts on annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on PO 00000 Frm 00113 Fmt 4701 Sfmt 4702 34025 the Eastern North Pacific stock of gray whales. Odontocetes This section builds on the broader discussion above and brings together the discussion of the different types and amounts of take that different species and stocks could potentially or would likely incur, the applicable mitigation, and the status of the species and stock to support the negligible impact determinations for each species or stock. We have described (earlier in this section) the unlikelihood of any masking having effects that would impact the reproduction or survival of any of the individual marine mammals affected by the Navy’s activities. We have also described above in the Potential Effects of Specified Activities on Marine Mammals and their Habitat section the unlikelihood of any habitat impacts having effects that would impact the reproduction or survival of any of the individual marine mammals affected by the Navy’s activities. For odontocetes, there is no anticipated M/ SI or tissue damage from sonar or explosives for any species. Here, we include information that applies to all of the odontocete species, which are then further divided and discussed in more detail in the following subsections: Sperm whales, dwarf sperm whales, and pygmy sperm whales; beaked whales; dolphins and small whales; and porpoises. These subsections include more specific information about the groups, as well as conclusions for each species or stock represented. The majority of takes by harassment of odontocetes in the NWTT Study Area are caused by sources from the MFAS bin (which includes hull-mounted sonar) because they are high level, typically narrowband sources at a frequency (in the 1–10 kHz range) that overlaps a more sensitive portion (though not the most sensitive) of the MF hearing range and they are used in a large portion of exercises (see Tables 3 and 4). For odontocetes other than beaked whales and porpoises (for which these percentages are indicated separately in those sections), most of the takes (96 percent) from the MF1 bin in the NWTT Study Area would result from received levels between 160 and 172 dB SPL. For the remaining active sonar bin types, the percentages are as follows: LF4 = 99 percent between 124 and 154 dB SPL, MF4 = 99 percent between 136 and 166 dB SPL, MF5 = 98 percent between 112 and 148 dB SPL, and HF4 = 95 percent between 100 and 160 dB SPL. Based on this information, the majority of the takes by Level B behavioral harassment are expected to E:\FR\FM\02JNP2.SGM 02JNP2 34026 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 be low to sometimes moderate in nature, but still of a generally shorter duration. For all odontocetes, takes from explosives (Level B behavioral harassment, TTS, or PTS) comprise a very small fraction (and low number) of those caused by exposure to active sonar. For the following odontocetes, zero takes from explosives are expected to occur: Common bottlenose dolphins, killer whales, short-beaked common dolphins, short-finned pilot whales, the Alaska stock of Dall’s porpoises, Southeast Alaska stock of harbor porpoises, sperm whales, Baird’s beaked whale, Cuvier’s beaked whale, and Mesoplodon species. For Level B behavioral disruption from explosives, with the exception of porpoises, one take is anticipated for the remaining species/stocks. For the CA/OR/WA stock of Dall’s porpoise and the remaining three harbor porpoise stocks 1–91 Level B behavioral takes from explosives are anticipated. Similarly the instances of TTS and PTS expected to occur from explosives for all remaining species/stocks, with the exception of porpoises, are anticipated to be low (1– 3 for TTS and 1 for PTS). Because of the lower TTS and PTS thresholds for HF odontocetes, for the CA/OR/WA stock of Dall’s porpoise and the remaining three harbor porpoise stocks, TTS takes range from 61–214 and PTS takes range from 27–86. Because the majority of harassment takes of odontocetes result from the sources in the MFAS bin, the vast majority of threshold shift would occur at a single frequency within the 1–10 kHz range and, therefore, the vast majority of threshold shift caused by Navy sonar sources would be at a single frequency within the range of 2–20 kHz. The frequency range within which any of the anticipated narrowband threshold shift would occur would fall directly within the range of most odontocete vocalizations (2–20 kHz). For example, the most commonly used hull-mounted sonar has a frequency around 3.5 kHz, and any associated threshold shift would be expected to be at around 7 kHz. However, odontocete vocalizations typically span a much wider range than this, and alternately, threshold shift from active sonar will often be in a narrower band (reflecting the narrower VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 band source that caused it), which means that TTS incurred by odontocetes would typically only interfere with communication within a portion of their range (if it occurred during a time when communication with conspecifics was occurring) and, as discussed earlier, it would only be expected to be of a short duration and relatively small degree. Odontocete echolocation occurs predominantly at frequencies significantly higher than 20 kHz, though there may be some small overlap at the lower part of their echolocating range for some species, which means that there is little likelihood that threshold shift, either temporary or permanent, would interfere with feeding behaviors. Many of the other critical sounds that serve as cues for navigation and prey (e.g., waves, fish, invertebrates) occur below a few kHz, which means that detection of these signals will not be inhibited by most threshold shift either. The low number of takes by threshold shift that might be incurred by individuals exposed to explosives would likely be lower frequency (5 kHz or less) and spanning a wider frequency range, which could slightly lower an individual’s sensitivity to navigational or prey cues, or a small portion of communication calls, for several minutes to hours (if temporary) or permanently. There is no reason to think that any of the individual odontocetes taken by TTS would incur these types of takes over more than one day, or over a few days at most, and therefore they are unlikely to incur impacts on reproduction or survival. PTS takes from these sources are very low, and while spanning a wider frequency band, are still expected to be of a low degree (i.e., low amount of hearing sensitivity loss) and unlikely to affect reproduction or survival. The range of potential behavioral effects of sound exposure on marine mammals generally, and odontocetes specifically, has been discussed in detail previously. There are behavioral patterns that differentiate the likely impacts on odontocetes as compared to mysticetes however. First, odontocetes echolocate to find prey, which means that they actively send out sounds to detect their prey. While there are many strategies for hunting, one common PO 00000 Frm 00114 Fmt 4701 Sfmt 4702 pattern, especially for deeper diving species, is many repeated deep dives within a bout, and multiple bouts within a day, to find and catch prey. As discussed above, studies demonstrate that odontocetes may cease their foraging dives in response to sound exposure. If enough foraging interruptions occur over multiple sequential days, and the individual either does not take in the necessary food, or must exert significant effort to find necessary food elsewhere, energy budget deficits can occur that could potentially result in impacts to reproductive success, such as increased cow/calf intervals (the time between successive calving). Second, while many mysticetes rely on seasonal migratory patterns that position them in a geographic location at a specific time of the year to take advantage of ephemeral large abundances of prey (i.e., invertebrates or small fish, which they eat by the thousands), odontocetes forage more homogeneously on one fish or squid at a time. Therefore, if odontocetes are interrupted while feeding, it is often possible to find more prey relatively nearby. Sperm Whale, Dwarf Sperm Whale, and Pygmy Sperm Whale This section builds on the broader odontocete discussion above and brings together the discussion of the different types and amounts of take that different species and stocks could potentially or would likely incur, the applicable mitigation, and the status of the species and stocks to support the preliminary negligible impact determinations for each species or stock. For sperm whales, there is no predicted PTS from sonar or explosives and no predicted tissue damage from explosives. For dwarf sperm whales and pygmy sperm whales (described as Kogia species below) no mortality or tissue damage from sonar or explosives is anticipated or proposed for authorization and only one PTS take is predicted. In Table 53 below for sperm whales and Kogia species, we indicate the total annual numbers of take by mortality, Level A and Level B harassment, and a number indicating the instances of total take as a percentage of abundance. E:\FR\FM\02JNP2.SGM 02JNP2 As discussed above, the majority of Level B harassment behavioral takes of odontocetes, and thereby sperm whales and Kogia species, is expected to be in the form of low to occasionally moderate severity of a generally shorter duration. As mentioned earlier in this section, we anticipate more severe effects from takes when animals are exposed to higher received levels or for longer durations. Occasional milder Level B behavioral harassment, as is expected here, is unlikely to cause longterm consequences for either individual animals or populations, even if some smaller subset of the takes are in the form of a longer (several hours or a day) and more moderate response. We note that Kogia species (dwarf and pygmy sperm whales), as HF-sensitive species, have a lower PTS threshold than all other groups and therefore are generally likely to experience larger amounts of TTS and PTS, and NMFS accordingly has evaluated and would authorize higher numbers. However, Kogia whales are still likely to avoid sound levels that would cause higher levels of TTS (greater than 20 dB) or PTS. Therefore, even though the number of TTS takes are higher than for other odontocetes, for all of the reasons described above, TTS and PTS are not expected to impact reproduction or survival of any individual. Below we compile and summarize the information that supports our preliminary determination that the Navy’s activities would not adversely affect sperm whales and pygmy and dwarf sperm whales through effects on annual rates of recruitment or survival. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Sperm Whale (California/Oregon/ Washington Stock) The SAR identifies the CA/OR/WA stock of sperm whales as ‘‘stable’’ and the species is listed as endangered under the ESA. No critical habitat has been designated for sperm whales under the ESA and there are no biologically important areas for sperm whales in the NWTT Study Area. NMFS proposes to authorize one mortality for the CA/OR/ WA stock of sperm whales over the seven years covered by this rule, or 0.14 mortality annually. The addition of this 0.14 annual mortality still leaves the total human-caused mortality under residual PBR (2.1) and below the insignificance threshold. No mortality from explosives and no Level A harassment is anticipated or proposed for authorization. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is 42 percent for sperm whales. Given the range of this stock (which extends the entire length of the West Coast, as well as beyond the U.S. EEZ boundary), this information indicates that only a portion of the individuals in the stock are likely to be impacted and repeated exposures of individuals are not anticipated. Additionally, while interrupted feeding bouts are a known response and concern for odontocetes, we also know that there are often viable alternative habitat options in the relative vicinity. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any PO 00000 Frm 00115 Fmt 4701 Sfmt 4702 34027 exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB (i.e., of a lower, to occasionally moderate, level and less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with sperm whale communication or other important lowfrequency cues, and that the associated lost opportunities and capabilities are not at a level that will impact reproduction or survival. Altogether, this population is stable (even though the species is listed under the ESA), only a portion of the stock is anticipated to be impacted, and any individual sperm whale is likely to be disturbed at a low-moderate level. No Level A harassment is anticipated or proposed to be authorized. This low magnitude and severity of harassment effects is not expected to result in impacts on individual reproduction or survival for any individuals, nor are these harassment takes combined with the proposed authorized mortality expected to adversely affect this stock through impacts on annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the CA/OR/WA stock of sperm whales. Kogia Species (California/Oregon/ Washington Stocks) The status of the CA/OR/WA stocks of pygmy and dwarf sperm whales (Kogia E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.009</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 34028 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 species) is unknown and neither are listed under the ESA. There are no biologically important areas for Kogia in the NWTT Study Area. No mortality or Level A harassment from tissue damage are anticipated or proposed for authorization, and one PTS Level A harassment take is expected and proposed for authorization. Due to their pelagic distribution, small size, and cryptic behavior, pygmy sperm whales and dwarf sperm whales (Kogia species) are rarely sighted during at-sea surveys and are difficult to distinguish between when visually observed in the field. Many of the relatively few observations of Kogia species off the U.S. West Coast were not identified to species. All at-sea sightings of Kogia species have been identified as pygmy sperm whales or Kogia species generally. Stranded dwarf sperm and pygmy sperm whales have been found on the U.S. West Coast, however dwarf sperm whale strandings are rare. NMFS SARs suggest that the majority of Kogia sighted off the U.S. West Coast were likely pygmy sperm whales. As such, the stock estimate in the NMFS SAR for pygmy sperm whales is the estimate derived for all Kogia species in the region (Barlow, 2016), and no separate abundance estimate can be determined for dwarf sperm whales, though some low number likely reside in the U.S. EEZ. Due to the lack of an abundance estimate it is not possible to predict the amount of Level A and Level B harassment take of dwarf sperm whales and therefore take estimates are identified as Kogia whales (including both pygmy and dwarf sperm whales). We assume only a small portion of those takes are likely to be dwarf sperm whales as the available information indicates that the density and abundance in the U.S. EEZ is low. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is 21 percent. Given the range of these stocks (which extends the entire length of the West Coast, as well VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 as beyond the U.S. EEZ boundary), this information indicates that only a portion of the individuals in the stocks are likely to be impacted and repeated exposures of individuals are not anticipated. Additionally, while interrupted feeding bouts are a known response and concern for odontocetes, we also know that there are often viable alternative habitat options in the relative vicinity. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB (i.e., of a lower, to occasionally moderate, level and less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with sperm whale communication or other important lowfrequency cues, and that the associated lost opportunities and capabilities are not at a level that will impact reproduction or survival. For these same reasons (low level and frequency band), while a small permanent loss of hearing sensitivity (PTS) may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, at the expected scale the estimated one Level A harassment take by PTS would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival of the affected individual. Thus, the one Level A harassment take by PTS for these stocks would be unlikely to affect rates of recruitment and survival for the stock. Altogether, although the status of the stocks is unknown, these species are not listed under the ESA as endangered or threatened, only a portion of these stocks is anticipated to be impacted, and any individual Kogia whale is likely to PO 00000 Frm 00116 Fmt 4701 Sfmt 4702 be disturbed at a low-moderate level. This low magnitude and severity of harassment effects is not expected to result in impacts on the reproduction or survival of any individuals, let alone have impacts on annual rates of recruitment or survival. One individual could be taken by PTS annually of likely low severity. A small permanent loss of hearing sensitivity (PTS) may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, but at the expected scale the estimated one Level A harassment take by PTS would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival of that individual, let alone affect annual rates of recruitment or survival. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the CA/OR/WA stocks of Kogia whales. Beaked Whales This section builds on the broader odontocete discussion above and brings together the discussion of the different types and amounts of take that different beaked whale species and stocks would likely incur, the applicable mitigation for stocks, and the status of the species and stocks to support the preliminary negligible impact determinations for each species or stock. For beaked whales, there is no anticipated Level A harassment by PTS or tissue damage from sonar or explosives, and no mortality is anticipated or proposed for authorization. In Table 54 below for beaked whales, we indicate the total annual numbers of take by mortality, Level A and Level B harassment, and a number indicating the instances of total take as a percentage of abundance. E:\FR\FM\02JNP2.SGM 02JNP2 This first paragraph provides specific information that is in lieu of the parallel information provided for odontocetes as a whole. The majority of takes by harassment of beaked whales in the NWTT Study Area are caused by sources from the MFAS bin (which includes hull-mounted sonar) because they are high level narrowband sources that fall within the 1–10 kHz range, which overlap a more sensitive portion (though not the most sensitive) of the MF hearing range. Also, of the sources expected to result in take, they are used in a large portion of exercises (see Tables 3 and 4). Most of the takes (95 percent) from the MF1 bin in the NWTT Study Area would result from received levels between 142 and 160 dB SPL. For the remaining active sonar bin types, the percentages are as follows: LF4 = 99 percent between 118 and 148 dB SPL, MF4 = 97 percent between 124 and 148 dB SPL, MF5 = 99 percent between 100 and 148 dB SPL, and HF4 = 97 percent between 100 and 154 dB SPL. Given the levels they are exposed to and beaked whale sensitivity, some responses would be of a lower severity, but many would likely be considered moderate, but still of generally short duration. Research has shown that beaked whales are especially sensitive to the presence of human activity (Pirotta et al., 2012; Tyack et al., 2011) and therefore have been assigned a lower harassment threshold, with lower received levels resulting in a higher percentage of individuals being harassed and a more distant distance cutoff (50 km for high source level, 25 km for moderate source level). VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Beaked whales have been documented to exhibit avoidance of human activity or respond to vessel presence (Pirotta et al., 2012). Beaked whales were observed to react negatively to survey vessels or low altitude aircraft by quick diving and other avoidance maneuvers, and none were observed to approach vessels (Wursig et al., 1998). It has been speculated for some time that beaked whales might have unusual sensitivities to sonar sound due to their likelihood of stranding in conjunction with MFAS use, although few definitive causal relationships between MFAS use and strandings have been documented (see Potential Effects of Specified Activities on Marine Mammals and their Habitat section). Research and observations show that if beaked whales are exposed to sonar or other active acoustic sources, they may startle, break off feeding dives, and avoid the area of the sound source to levels of 157 dB re: 1 mPa, or below (McCarthy et al., 2011). Acoustic monitoring during actual sonar exercises revealed some beaked whales continuing to forage at levels up to 157 dB re: 1 mPa (Tyack et al., 2011). Stimpert et al. (2014) tagged a Baird’s beaked whale, which was subsequently exposed to simulated MFAS. Changes in the animal’s dive behavior and locomotion were observed when received level reached 127 dB re: 1 mPa. However, Manzano-Roth et al. (2013) found that for beaked whale dives that continued to occur during MFAS activity, differences from normal dive profiles and click rates were not PO 00000 Frm 00117 Fmt 4701 Sfmt 4702 34029 detected with estimated received levels up to 137 dB re: 1 mPa while the animals were at depth during their dives. In research done at the Navy’s fixed tracking range in the Bahamas, animals were observed to leave the immediate area of the anti-submarine warfare training exercise (avoiding the sonar acoustic footprint at a distance where the received level was ‘‘around 140 dB SPL’’, according to Tyack et al. (2011)), but return within a few days after the event ended (Claridge and Durban, 2009; McCarthy et al., 2011; Moretti et al., 2009, 2010; Tyack et al., 2010, 2011). Tyack et al. (2011) report that, in reaction to sonar playbacks, most beaked whales stopped echolocating, made long slow ascent to the surface, and moved away from the sound. A similar behavioral response study conducted in Southern California waters during the 2010–2011 field season found that Cuvier’s beaked whales exposed to MFAS displayed behavior ranging from initial orientation changes to avoidance responses characterized by energetic fluking and swimming away from the source (DeRuiter et al., 2013b). However, the authors did not detect similar responses to incidental exposure to distant naval sonar exercises at comparable received levels, indicating that context of the exposures (e.g., source proximity, controlled source ramp-up) may have been a significant factor. The study itself found the results inconclusive and meriting further investigation. Cuvier’s beaked whale responses suggested particular sensitivity to sound exposure consistent E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.010</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 34030 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules with results for Blainville’s beaked whale. Populations of beaked whales and other odontocetes on the Bahamas and other Navy fixed ranges that have been operating for decades appear to be stable. Behavioral reactions (avoidance of the area of Navy activity) seem likely in most cases if beaked whales are exposed to anti-submarine sonar within a few tens of kilometers, especially for prolonged periods (a few hours or more) since this is one of the most sensitive marine mammal groups to anthropogenic sound of any species or group studied to date and research indicates beaked whales will leave an area where anthropogenic sound is present (De Ruiter et al., 2013; Manzano-Roth et al., 2013; Moretti et al., 2014; Tyack et al., 2011). Research involving tagged Cuvier’s beaked whales in the SOCAL Range Complex reported on by Falcone and Schorr (2012, 2014) indicates year-round prolonged use of the Navy’s training and testing area by these beaked whales and has documented movements in excess of hundreds of kilometers by some of those animals. Given that some of these animals may routinely move hundreds of kilometers as part of their normal pattern, leaving an area where sonar or other anthropogenic sound is present may have little, if any, cost to such an animal. Photo identification studies in the SOCAL Range Complex, a Navy range that is utilized for training and testing, have identified approximately 100 Cuvier’s beaked whale individuals with 40 percent having been seen in one or more prior years, with re-sightings up to seven years apart (Falcone and Schorr, 2014). These results indicate long-term residency by individuals in an intensively used Navy training and testing area, which may also suggest a lack of long-term consequences as a result of exposure to Navy training and testing activities. More than eight years of passive acoustic monitoring on the Navy’s instrumented range west of San Clemente Island documented no significant changes in annual and monthly beaked whale echolocation clicks, with the exception of repeated fall declines likely driven by natural beaked whale life history functions (DiMarzio et al., 2018). Finally, results from passive acoustic monitoring estimated that regional Cuvier’s beaked whale densities were higher than indicated by NMFS’ broad scale visual surveys for the United States West Coast (Hildebrand and McDonald, 2009). Below we compile and summarize the information that supports our preliminary determination that the Navy’s activities would not adversely VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 affect beaked whales through effects on annual rates of recruitment or survival. Baird’s and Cuvier’s Beaked Whales and Mesoplodon Species (California/ Oregon/Washington Stocks) The CA/OR/WA stocks of Baird’s beaked whale, Cuvier’s beaked whale, and Mesoplodon species are not listed as endangered or threatened species under the ESA, and have been identified as ‘‘stable,’’ ‘‘decreasing,’’ and ‘‘increasing,’’ respectively, in the SARs. There are no biologically important areas for beaked whales in the NWTT Study Area. No mortality or Level A harassment from sonar or explosives is expected or proposed for authorization. No methods are available to distinguish between the six species of Mesoplodon beaked whales from the CA/OR/WA stocks (Blainville’s beaked whale (M. densirostris), Perrin’s beaked whale (M. perrini), Lesser beaked whale (M. peruvianus), Stejneger’s beaked whale (M. stejnegeri), Gingko-toothed beaked whale (M. gingkodens), and Hubbs’ beaked whale (M. carlhubbsi)) when observed during at-sea surveys (Carretta et al., 2019). Bycatch and stranding records from the region indicate that Hubb’s beaked whale is the most commonly encountered (Carretta et al., 2008, Moore and Barlow, 2013). As indicated in the SAR, no speciesspecific abundance estimates are available, the abundance estimate includes all CA/OR/WA Mesoplodon species, and the six species are managed as one unit. Due to the lack of speciesspecific abundance estimates it is not possible to predict the take of individual species and take estimates are identified as Mesoplodon species. Therefore our analysis considers these Mesoplodon species together. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance is 36 to 78 percent. This information indicates that up to 78 percent of the individuals in these stocks are likely to be impacted, depending on the stock, though the more likely scenario is that a smaller portion than that would be taken, and a subset of them would be taken on a few days, with no indication that these days would be sequential. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 166 dB, though with beaked whales, which are considered somewhat more sensitive, PO 00000 Frm 00118 Fmt 4701 Sfmt 4702 this could mean that some individuals will leave preferred habitat for a day (i.e., moderate level takes). However, while interrupted feeding bouts are a known response and concern for odontocetes, we also know that there are often viable alternative habitat options nearby. Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with beaked whale communication or other important lowfrequency cues, and that the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. As mentioned earlier in the odontocete overview, we anticipate more severe effects from takes when animals are exposed to higher received levels or sequential days of impacts. Altogether, none of these species are listed as threatened or endangered under the ESA, only a portion of the stocks are anticipated to be impacted, and any individual beaked whale is likely to be disturbed at a moderate or sometimes low level. This low magnitude and low to moderate severity of harassment effects is not expected to result in impacts on individual reproduction or survival, let alone annual rates of recruitment or survival. No mortality and no Level A harassment is anticipated or proposed for authorization. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on the CA/OR/WA stocks of beaked whales. Dolphins and Small Whales This section builds on the broader odontocete discussion above and brings together the discussion of the different types and amounts of take that different dolphin and small whale species and stocks would likely incur, the applicable mitigation for stocks, and the status of the species and stocks to support the preliminary negligible impact determinations for each species or stock. For all dolphin and small whale stocks discussed here except for the CA/OR/WA stocks of Northern right whale dolphin and Pacific white-sided dolphin there is no predicted PTS from sonar or explosives, and no mortality or tissue damage from sonar or explosives is anticipated or proposed for authorization. For the CA/OR/WA stocks of Northern right whale dolphin and Pacific white-sided dolphin no mortality or tissue damage from sonar or explosives is anticipated or proposed for authorization and one Level A E:\FR\FM\02JNP2.SGM 02JNP2 34031 harassment by PTS from testing activities is predicted for each stock. In Table 55 below for dolphins and small whales, we indicate the total annual numbers of take by mortality, Level A harassment and Level B harassment, and a number indicating the instances of total take as a percentage of abundance. As described above, the large majority of Level B behavioral harassment to odontocetes, and thereby dolphins and small whales, from hull-mounted sonar (MFAS) in the NWTT Study Area would result from received levels between 160 and 172 dB SPL. Therefore, the majority of Level B harassment takes are expected to be in the form of low to occasionally moderate responses of a generally shorter duration. As mentioned earlier in this section, we anticipate more severe effects from takes when animals are exposed to higher received levels. Occasional milder occurrences of Level B behavioral harassment are unlikely to cause longterm consequences for individual animals or populations that have any effect on reproduction or survival. Research and observations show that if delphinids are exposed to sonar or other active acoustic sources they may react in a number of ways depending on their experience with the sound source and what activity they are engaged in at the time of the acoustic exposure. Delphinids may not react at all until the sound source is approaching within a few hundred meters to within a few kilometers depending on the environmental conditions and species. Some dolphin species (the more surfacedwelling taxa—typically those with ‘‘dolphin’’ in the common name, such as bottlenose dolphins, spotted dolphins, spinner dolphins, roughtoothed dolphins, etc., but not Risso’s dolphin), especially those residing in more industrialized or busy areas, have demonstrated more tolerance for disturbance and loud sounds and many VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00119 Fmt 4701 Sfmt 4702 E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.011</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules 34032 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 of these species are known to approach vessels to bow-ride. These species are often considered generally less sensitive to disturbance. Dolphins and small whales that reside in deeper waters and generally have fewer interactions with human activities are more likely to demonstrate more typical avoidance reactions and foraging interruptions as described above in the odontocete overview. Below we compile and summarize the information that supports our preliminary determination that the Navy’s activities would not adversely affect dolphins and small whales through effects on annual rates of recruitment or survival. Killer Whales (Eastern North Pacific Alaskan Resident, West Coast Transient, Eastern North Pacific Offshore, and Eastern North Pacific Southern Resident Stocks) With the exception of the Eastern North Pacific Southern Resident stock (Southern Resident killer whale DPS) which is listed as endangered under the ESA, killer whale stocks in the NWTT Study Area are not listed under the ESA. ESA-designated critical habitat for the Southern Resident killer whale DPS overlaps with the NWTT Study area in the Strait of Juan de Fuca. No biologically important areas for killer whales have been identified in the NWTT Study Area. The Eastern North Pacific Southern Resident stock is small (75 individuals) and has been decreasing in recent years. The Eastern North Pacific Offshore stock is reported as ‘‘stable’’, and the other stocks have unknown population trends. No mortality or Level A harassment is anticipated or proposed for authorization for any of these stocks. The proposed Marine Species Coastal, Olympic Coast National Marine Sanctuary, Stonewall and Heceta Bank Humpback Whale, Point St. George Humpback Whale, and Puget Sound and Strait of Juan de Fuca Mitigation Areas overlap with important Eastern North Pacific Southern Resident (Southern Resident DPS) killer whale foraging and migration habitat. Procedural mitigation along with the mitigation measures implemented in each of these areas include no MF1 MFAS use seasonally or limited MFAS use year round, no explosive training, etc. (see details for each area in the Proposed Mitigation Measures section), would reduce the severity of impacts to Eastern North Pacific Southern Resident (Southern Resident DPS) killer whales by reducing interference in feeding and migration that could result in lost feeding opportunities or necessitate additional VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 energy expenditure to find other good foraging opportunities or migration routes. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance ranges from 1 percent (Eastern North Pacific Alaskan Resident) to 95 percent (West Coast Transient). The number of estimated total instances of take compared to the abundance for the Eastern North Pacific Southern Resident is 68 percent. This information indicates that only a very small portion of the Eastern North Pacific Alaskan Resident stock is likely impacted and repeated exposures of individuals are not anticipated. This information also indicates that a few to up to 95 percent of individuals of the remaining three stocks could be impacted, if each were taken only one day per year, though the more likely scenario is that a smaller portion than that would be taken, and a subset of them would be taken multiple days with no indication that these days would be sequential. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB (i.e., of a lower, to occasionally moderate, level and less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with killer whale communication or other important lowfrequency cues, and that the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. Altogether, with the exception of the Eastern North Pacific Southern Resident stock which is listed as endangered under the ESA, these killer whale stocks are not listed under the ESA. Only a portion of these killer whale stocks is anticipated to be impacted, and any individual is likely to be disturbed at a low-moderate level, with the taken individuals likely exposed on one day or a few days. Even acknowledging the small and declining stock size of the Eastern North Pacific Southern Resident stock, this low magnitude and severity of harassment effects is unlikely to result in impacts on individual reproduction or survival, much less annual rates of recruitment or survival of any of the stocks. No mortality or Level A harassment is anticipated or proposed for authorization for any of the PO 00000 Frm 00120 Fmt 4701 Sfmt 4702 stocks. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on these killer whale stocks. All other dolphin and small whale stocks None of these stocks is listed under the ESA and their stock statuses are considered ‘‘unknown,’’ except for the CA/OR/WA stock of short-beaked common dolphin which is described as ‘‘increasing’’. No biologically important areas for these stocks have been identified in the NWTT Study Area. No mortality or serious injury is anticipated or proposed for authorization. With the exception of one Level A harassment PTS take to the CA/OR/WA stocks of Northern right whale dolphin and Pacific white-sided dolphin, no Level A harassment by PTS or tissue damage is expected or proposed for authorization for these stocks. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), the number of estimated total instances of take compared to the abundance ranges from less than 1 percent (North Pacific stock of Pacific white-sided dolphins, CA/OR/WA Offshore stock of common bottlenose dolphins, and CA/OR/WA stock of short-beaked common dolphin) to 100 percent (CA/OR/WA stock of Risso’s dolphins). All stocks except for the CA/ OR/WA stocks of Risso’s dolphin, Pacific white-sided dolphin, and Northern right whale dolphin have estimated total instances of take compared to the abundances less than or equal to 11 percent. This information indicates that only a small portion of these stocks is likely impacted and repeated exposures of individuals are not anticipated. The CA/OR/WA stocks of Risso’s dolphins, Pacific white-sided dolphin, and Northern right whale dolphin have estimated total instances of take compared to the abundances that range from 78 to 100 percent. This information indicates that up to 100 percent of the individuals of these stocks could be impacted, if each were taken only one day per year, though the more likely scenario is that a smaller portion than that would be taken, and a subset of them would be taken on a few days, with no indication that these days would be sequential. Regarding the severity of those individual Level B harassment takes by behavioral disruption, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB (i.e., of a E:\FR\FM\02JNP2.SGM 02JNP2 34033 lower, to occasionally moderate, level and less likely to evoke a severe response). However, while interrupted feeding bouts are a known response and concern for odontocetes, we also know that there are often viable alternative habitat options nearby. Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with dolphin and small whale communication or other important lowfrequency cues, and that the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. For these same reasons (low level and frequency band), while a small permanent loss of hearing sensitivity (PTS) may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, at the expected scale the estimated one Level A harassment take by PTS for the CA/OR/WA stocks of Northern right whale dolphin and Pacific white-sided dolphin would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival of that individual. Thus the one Level A harassment take by PTS for these stocks would be unlikely to affect rates of recruitment and survival for the stock. Altogether, though the status of these stocks is largely unknown, none of these stocks is listed under the ESA and any individual is likely to be disturbed at a low-moderate level, with the taken individuals likely exposed on one to a few days. This low magnitude and severity of harassment effects is not expected to result in impacts on individual reproduction or survival. One individual each from the CA/OR/ WA stocks of Northern right whale dolphin and Pacific white-sided dolphin could be taken by PTS annually of likely low severity. A small permanent loss of hearing sensitivity (PTS) may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, but at the expected scale the estimated Level A harassment takes by PTS for the CA/OR/ WA stocks of Northern right whale dolphin and Pacific white-sided dolphin would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival of any individuals, let alone annual rates of recruitment or survival. No mortality is anticipated or proposed for authorization. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on these stocks of small whales and dolphins. The majority of takes by harassment of harbor porpoises in the NWTT Study Area are caused by sources from the MFAS bin (which includes hull- mounted sonar) because they are high level sources at a frequency (1–10 kHz), which overlaps a more sensitive portion (though not the most sensitive) of the HF hearing range, and of the sources expected to result in take, they are used in a large portion of exercises (see Tables 3 and 4). Most of the takes (90 VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 PO 00000 Frm 00121 Fmt 4701 Sfmt 4702 Porpoises This section builds on the broader odontocete discussion above and brings together the discussion of the different types and amounts of take that different porpoise species or stocks would likely incur, the applicable mitigation, and the status of the species and stock to support the negligible impact determinations for each species or stock. For porpoises, there is no anticipated M/SI or tissue damage from sonar or explosives for any species. In Table 56 below for porpoises, we indicate the total annual numbers of take by mortality, Level A harassment and Level B harassment, and a number indicating the instances of total take as a percentage of abundance. E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.012</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 34034 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules percent) from the MF1 bin in the NWTT Study Area would result from received levels between 148 and 166 dB SPL. For the remaining active sonar bin types, the percentages are as follows: LF4 = 99 percent between 124 and 142 dB SPL, MF4 = 97 percent between 124 and 148 dB SPL, MF5 = 97 percent between 118 and 142 dB SPL, and HF4 = 97 percent between 118 and 160 dB SPL. Given the levels they are exposed to and harbor porpoise sensitivity, some responses would be of a lower severity, but many would likely be considered moderate, but still of generally short duration. Harbor porpoises have been shown to be particularly sensitive to human activity (Tyack et al., 2011; Pirotta et al., 2012). The information currently available regarding harbor porpoises suggests a very low threshold level of response for both captive (Kastelein et al., 2000; Kastelein et al., 2005) and wild (Johnston, 2002) animals. Southall et al. (2007) concluded that harbor porpoises are likely sensitive to a wide range of anthropogenic sounds at low received levels (approximately 90 to 120 dB). Research and observations of harbor porpoises for other locations show that this species is wary of human activity and will display profound avoidance behavior for anthropogenic sound sources in many situations at levels down to 120 dB re: 1 mPa (Southall, 2007). Harbor porpoises routinely avoid and swim away from large motorized vessels (Barlow et al., 1988; Evans et al., 1994; Palka and Hammond, 2001; Polacheck and Thorpe, 1990). Harbor porpoises may startle and temporarily leave the immediate area of the training or testing until after the event ends. Accordingly, harbor porpoises have been assigned a lower Level B behavioral harassment threshold, i.e., a more distant distance cutoff (40 km for high source level, 20 km for moderate source level) and, as a result, the number of harbor porpoise taken by Level B behavioral harassment through exposure to LFAS/MFAS/HFAS in the NWTT Study Area is generally higher than the other species. As mentioned earlier in the odontocete overview, we anticipate more severe effects from takes when animals are exposed to higher received levels or sequential days of impacts; occasional low to moderate behavioral reactions are unlikely to affect reproduction or survival. Some takes by Level B behavioral harassment could be in the form of a longer (several hours or a day) and more moderate response, but unless they are repeated over more than several sequential days, impacts to reproduction or survival are not VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 anticipated. Even where some smaller number of animals could experience effects on reproduction (which could happen to a small number), for the reasons explained below this would not affect rates of recruitment or survival, especially given the status of the stocks. While harbor porpoises have been observed to be especially sensitive to human activity, the same types of responses have not been observed in Dall’s porpoises. Dall’s porpoises are typically notably longer than, and weigh more than twice as much as, harbor porpoises, making them generally less likely to be preyed upon and likely differentiating their behavioral repertoire somewhat from harbor porpoises. Further, they are typically seen in large groups and feeding aggregations, or exhibiting bow-riding behaviors, which is very different from the group dynamics observed in the more typically solitary, cryptic harbor porpoises, which are not often seen bow-riding. For these reasons, Dall’s porpoises are not treated as an especially sensitive species (versus harbor porpoises which have a lower behavioral harassment threshold and more distant cutoff) but, rather, are analyzed similarly to other odontocetes (with takes from the sonar bin in the NWTT Study Area resulting from the same received levels reported in the Odontocete section above). Therefore, the majority of Level B takes are expected to be in the form of milder responses compared to higher level exposures. As mentioned earlier in this section, we anticipate more severe effects from takes when animals are exposed to higher received levels. All Porpoise Stocks These Dall’s and harbor porpoise stocks are not listed under the ESA and the status of these stocks is considered ‘‘unknown.’’ There are no biologically important areas for Dall’s and harbor porpoises in the NWTT Study Area. However, a known important feeding area for harbor porpoises overlaps with the Stonewall and Heceta Bank Humpback Whale Mitigation Area. No MF1 MFAS or explosives would be used in this mitigation area from May 1— November 30, which would reduce the severity of impacts to harbor porpoises by reducing interference in feeding that could result in lost feeding opportunities or necessitate additional energy expenditure to find other good opportunities. No mortality or Level A harassment from tissue damage is expected or proposed to be authorized for any of these stocks. Regarding the magnitude of Level B harassment takes (TTS and behavioral PO 00000 Frm 00122 Fmt 4701 Sfmt 4702 disruption), the number of estimated total instances of take compared to the abundance ranges from less than 1 percent for the Alaska stock of Dall’s porpoises to 265 percent for the Washington Inland Waters stock of harbor porpoises. The Alaska stock of Dall’s porpoises, and Southeast Alaska and Northern California/Southern Oregon stocks of harbor porpoises have estimated total instances of take compared to the abundances less than or equal to 10 percent. This information indicates that only a small portion of these stocks is likely impacted and repeated exposures of individuals are not anticipated. The CA/OR/WA stock of Dall’s porpoises and the Northern Washington/Oregon Coast and Washington Inland Waters stocks of harbor porpoises have estimated total instances of take compared to the abundances that range from 131 to 265 percent. This information indicates that all individuals of these stocks could be impacted, if each were taken two to three days per year, though the more likely scenario is that a smaller portion would be taken, and a subset of those would be on more days (maybe 5 or 6), with no indication that these days would be sequential. Given this and the larger number of total takes (totally and to individuals), it is more likely (probabilistically) that some small number of individuals could be interrupted during foraging in a manner and amount such that impacts to the energy budgets of females (from either losing feeding opportunities or expending considerable energy to find alternative feeding options) could cause them to forego reproduction for a year. Energetic impacts to males are generally meaningless to population rates unless they cause death, and it takes extreme energy deficits beyond what would ever be likely to result from these activities to cause the death of an adult marine mammal. However, foregone reproduction (especially for only one year within seven, which is the maximum predicted because the small number anticipated in any one year makes the probability that any individual will be impacted in this way twice in seven years very low) has far less of an impact on population rates than mortality and a small number of instances would not be expected to adversely impact annual rates of recruitment or survival. All indications are that the number of times in which reproduction would be likely to be foregone would not affect the stocks’ annual rates of recruitment or survival. Regarding the severity of those individual Level B harassment takes by E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules khammond on DSKJM1Z7X2PROD with PROPOSALS2 behavioral disruption for harbor porpoises, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 166 dB, which for harbor porpoise (which have a lower behavioral Level B harassment threshold) would mostly be considered a moderate level. Regarding the severity of those individual Level B harassment takes by behavioral disruption for Dall’s porpoises, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 172 dB (i.e., of a lower, to occasionally moderate, level and less likely to evoke a severe response). Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with communication or other important low-frequency cues. The associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. No Level A harassment by PTS is anticipated or proposed for the Southeast Alaska stock of harbor porpoise or the Alaska stock of Dall’s porpoise. For the remaining porpoise stocks, for the same reasons explained above for TTS (low level and the likely frequency band), while a small permanent loss of hearing sensitivity may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, the estimated annual Level A harassment takes by PTS for these three stocks of harbor porpoises and one stock of Dall’s porpoises (86 to 180) would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival for most individuals. Because of the higher number of PTS takes, however, we acknowledge that a few animals could potentially incur permanent hearing loss of a higher degree that could potentially interfere with their successful reproduction and growth. Given the large population sizes of these stocks, even if these occurred, it would not adversely impact rates of recruitment or survival. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Altogether, the status of the harbor porpoise stocks is unknown, however harbor porpoises are not listed as endangered or threatened under the ESA. Because harbor porpoises are particularly sensitive, it is likely that a fair number of the Level B behavioral responses of individuals will be of a moderate nature. Additionally, as noted, some portion of the stocks may be taken repeatedly on up to several days within a year, however this is not anticipated to affect the stocks’ annual rates of recruitment or survival. Some individuals (86 to 180) from the Northern Oregon/Washington Coast, Northern California/Southern Oregon, and Washington Inland Waters stocks of harbor porpoises could be taken by PTS annually of likely low severity. A small permanent loss of hearing sensitivity (PTS) may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, but at the expected scale the estimated Level A harassment takes by PTS for these stocks would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival of any individuals, let alone annual rates of recruitment or survival. No mortality is anticipated or proposed for authorization. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on all four stocks of harbor porpoises. Altogether, the status of the Dall’s porpoise stocks is unknown, however Dall’s porpoises are not listed as endangered or threatened under the ESA. Any individual Dall’s porpoise is likely to be disturbed at a low-moderate level, with the taken individuals likely exposed on one to a few days. This low magnitude and severity of Level B harassment effects is not expected to result in impacts on individual reproduction or survival, much less annual rates of recruitment or survival. Some individuals (98) from the CA/OR/WA stock of Dall’s porpoises could be taken by PTS annually of likely low severity. A small permanent loss of hearing sensitivity (PTS) may include PO 00000 Frm 00123 Fmt 4701 Sfmt 4702 34035 some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, but at the expected scale the estimated Level A harassment takes by PTS for this stock would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival of any individuals, let alone annual rates of recruitment or survival. No mortality is anticipated or proposed for authorization. For these reasons, we have preliminarily determined, in consideration of all of the effects of the Navy’s activities combined, that the proposed authorized take would have a negligible impact on these stocks of Dall’s porpoises. Pinnipeds This section builds on the broader discussion above and brings together the discussion of the different types and amounts of take that different species and stocks would likely incur, the applicable mitigation, and the status of the species and stocks to support the negligible impact determinations for each species or stock. We have described (earlier in this section) the unlikelihood of any masking having effects that would impact the reproduction or survival of any of the individual marine mammals affected by the Navy’s activities. We have also described above in the Potential Effects of Specified Activities on Marine Mammals and their Habitat section the unlikelihood of any habitat impacts having effects that would impact the reproduction or survival of any of the individual marine mammals affected by the Navy’s activities. For pinnipeds, there is no mortality or serious injury and no Level A harassment from tissue damage from sonar or explosives anticipated or proposed to be authorized for any species. Here, we include information that applies to all of the pinniped species. In Table 57 below for pinnipeds, we indicate the total annual numbers of take by mortality, Level A harassment and Level B harassment, and a number indicating the instances of total take as a percentage of abundance. E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules The majority of takes by harassment of pinnipeds in the NWTT Study Area are caused by sources from the MFAS bin (which includes hull-mounted sonar) because they are high level sources at a frequency (1–10 kHz) which overlaps the most sensitive portion of the pinniped hearing range, and of the sources expected to result in take, they are used in a large portion of exercises (see Tables 3 and 4). Most of the takes (97 percent) from the MF1 bin in the NWTT Study Area would result from received levels between 166 and 178 dB SPL. For the remaining active sonar bin types, the percentages are as follows: LF4 = 97 percent between 130 and 160 dB SPL, MF4 = 99 percent between 142 and 172 dB SPL, MF5 = 97 percent between 130 and 160 dB SPL, and HF4 VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 = 99 percent between 100 and 172 dB SPL. Given the levels they are exposed to and pinniped sensitivity, most responses would be of a lower severity, with only occasional responses likely to be considered moderate, but still of generally short duration. As mentioned earlier in this section, we anticipate more severe effects from takes when animals are exposed to higher received levels. Occasional milder takes by Level B behavioral harassment are unlikely to cause longterm consequences for individual animals or populations, especially when they are not expected to be repeated over sequential multiple days. For all pinnipeds, harassment takes from explosives (behavioral, TTS, or PTS if present) comprise a very small fraction PO 00000 Frm 00124 Fmt 4701 Sfmt 4702 of those caused by exposure to active sonar. Because the majority of harassment take of pinnipeds results from narrowband sources in the range of 1– 10 kHz, the vast majority of threshold shift caused by Navy sonar sources will typically occur in the range of 2–20 kHz. This frequency range falls within the range of pinniped hearing, however, pinniped vocalizations typically span a somewhat lower range than this (<0.2 to 10 kHz) and threshold shift from active sonar will often be in a narrower band (reflecting the narrower band source that caused it), which means that TTS incurred by pinnipeds would typically only interfere with communication within a portion of a pinniped’s range (if it occurred during a time when E:\FR\FM\02JNP2.SGM 02JNP2 EP02JN20.013</GPH> khammond on DSKJM1Z7X2PROD with PROPOSALS2 34036 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules communication with conspecifics was occurring). As discussed earlier, it would only be expected to be of a short duration and relatively small degree. Many of the other critical sounds that serve as cues for navigation and prey (e.g., waves, fish, invertebrates) occur below a few kHz, which means that detection of these signals will not be inhibited by most threshold shifts either. The very low number of takes by threshold shifts that might be incurred by individuals exposed to explosives would likely be lower frequency (5 kHz or less) and spanning a wider frequency range, which could slightly lower an individual’s sensitivity to navigational or prey cues, or a small portion of communication calls, for several minutes to hours (if temporary) or permanently. Regarding behavioral disturbance, research and observations show that pinnipeds in the water may be tolerant of anthropogenic noise and activity (a review of behavioral reactions by pinnipeds to impulsive and nonimpulsive noise can be found in Richardson et al. (1995) and Southall et al. (2007)). Available data, though limited, suggest that exposures between approximately 90 and 140 dB SPL do not appear to induce strong behavioral responses in pinnipeds exposed to nonpulse sounds in water (Costa et al., 2003; Jacobs and Terhune, 2002; Kastelein et al., 2006c). Based on the limited data on pinnipeds in the water exposed to multiple pulses (small explosives, impact pile driving, and seismic sources), exposures in the approximately 150 to 180 dB SPL range generally have limited potential to induce avoidance behavior in pinnipeds (Blackwell et al., 2004; Harris et al., 2001; Miller et al., 2004). If pinnipeds are exposed to sonar or other active acoustic sources they may react in a number of ways depending on their experience with the sound source and what activity they are engaged in at the time of the acoustic exposure. Pinnipeds may not react at all until the sound source is approaching within a few hundred meters and then may alert, ignore the stimulus, change their behaviors, or avoid the immediate area by swimming away or diving. Effects on pinnipeds that are taken by Level B harassment in the NWTT Study Area, on the basis of reports in the literature as well as Navy monitoring from past activities, will likely be limited to reactions such as increased swimming speeds, increased surfacing time, or decreased foraging (if such activity were occurring). Most likely, individuals will simply move away from the sound VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 source and be temporarily displaced from those areas, or not respond at all, which would have no effect on reproduction or survival. In areas of repeated and frequent acoustic disturbance, some animals may habituate or learn to tolerate the new baseline or fluctuations in noise level. Habituation can occur when an animal’s response to a stimulus wanes with repeated exposure, usually in the absence of unpleasant associated events (Wartzok et al., 2003). While some animals may not return to an area, or may begin using an area differently due to training and testing activities, most animals are expected to return to their usual locations and behavior. Given their documented tolerance of anthropogenic sound (Richardson et al., 1995 and Southall et al., 2007), repeated exposures of individuals of any of these species to levels of sound that may cause Level B harassment are unlikely to result in hearing impairment or to significantly disrupt foraging behavior. Thus, even repeated Level B harassment of some small subset of individuals of an overall stock is unlikely to result in any significant realized decrease in fitness to those individuals that would result in any adverse impact on rates of recruitment or survival for the stock as a whole. Of these stocks, only Guadalupe fur seals are listed as threatened under the ESA and the SAR indicates the stock is ‘‘increasing.’’ No critical habitat under the ESA is designated for the Guadalupe fur seal. The other stocks are not ESAlisted. Biologically important areas have not been identified for pinnipeds. There are active UMEs for Guadalupe fur seals and California sea lions. Since 2015 there have been 400 strandings of Guadalupe fur seals (including live and dead seals). The California sea lion UME is anticipated to be closed soon as elevated strandings occurred from 2013–2016. All of the other pinniped stocks are considered ‘‘increasing,’’ ‘‘stable,’’ or ‘‘unknown’’ except for Northern fur seals (Eastern Pacific stock), which is considered ‘‘declining’’. No mortality or Level A harassment from tissue damage is anticipated or proposed for authorization. All the pinniped species discussed in this section would benefit from the procedural mitigation measures described earlier in the Proposed Mitigation Measures section. Regarding the magnitude of Level B harassment takes (TTS and behavioral disruption), for Guadalupe fur seals, the estimated instances of takes as compared to the stock abundance is 4 percent. This information indicates that only a small portion of individuals in PO 00000 Frm 00125 Fmt 4701 Sfmt 4702 34037 the stock are likely impacted and repeated exposures of individuals are not anticipated. With the exception of the Hood Canal and Southern Puget Sound stocks of harbor seals, for the remaining stocks the number of estimated total instances of take compared to the abundance is 2–15 percent. Given the ranges of these stocks (i.e., large ranges, but with individuals often staying in the vicinity of haulouts), this information indicates that a small portion of individuals in the stock are likely impacted and repeated exposures of individuals are not anticipated. For the Southern Puget Sound stock of harbor seals, the number of estimated total instances of take compared to the abundance is 168 percent. This information indicates that all individuals in this stock could be impacted, if each were taken up to 1– 2 days per year, though the more likely scenario is that a smaller portion than that would be taken, and a subset of them would be taken on 3 or 4 days, with no indication that these days would be sequential. For the Hood Canal stock of harbor seals, the number of estimated total instances of take compared to the abundance is 3,084 percent. This information indicates that all individuals of this stock could be impacted, if each were taken up to 31 days per year, though the more likely scenario is that a subset of them would be taken on fewer than 31 days and a subset would be taken on more than 31 days, and for those taken on a higher number of days, some of those days may be sequential. Though the majority of impacts are expected to be of a lower to sometimes moderate severity, the repeated takes over a potentially fair number of sequential days for some individuals in the Hood Canal stock of harbor seals makes it more likely that some number of individuals could be interrupted during foraging in a manner and amount such that impacts to the energy budgets of females (from either losing feeding opportunities or expending considerable energy to find alternative feeding options) could cause them to forego reproduction for a year (energetic impacts to males are generally meaningless to population rates unless they cause death, and it takes extreme energy deficits beyond what would ever be likely to result from these activities to cause the death of an adult marine mammal). As noted previously, however, foregone reproduction (especially for only one year within seven, which is the maximum predicted because the small number anticipated in any one year makes the probability that E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 34038 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules any individual will be impacted in this way twice in seven years very low) has far less of an impact on population rates than mortality and a relatively small number of instances of foregone reproduction would not be expected to adversely affect the stock through effects on annual rates of recruitment or survival. Regarding the severity of those individual takes by Level B behavioral harassment for all pinniped stocks, we have explained that the duration of any exposure is expected to be between minutes and hours (i.e., relatively short) and the received sound levels largely below 178 dB, which is considered a relatively low to occasionally moderate level for pinnipeds. However, as noted, for the Hood Canal stock, some of these takes could occur on some number of sequential days. Regarding the severity of TTS takes, they are expected to be low-level, of short duration, and mostly not in a frequency band that would be expected to interfere with pinniped communication or other important lowfrequency cues, and that the associated lost opportunities and capabilities are not at a level that would impact reproduction or survival. For these same reasons (low level and frequency band), while a small permanent loss of hearing sensitivity may include some degree of energetic costs for compensating or may mean some small loss of opportunities or detection capabilities, the 1–5 estimated Level A harassment takes by PTS for California sea lions, Northern elephant seals, and the Washington Northern inland waters, Hood Canal, OR/WA Coast, and Southern Puget Sound stocks of harbor seals would be unlikely to impact behaviors, opportunities, or detection capabilities to a degree that would interfere with reproductive success or survival of any individuals. Altogether, all pinniped stocks are considered ‘‘increasing,’’ ‘‘stable,’’ or ‘‘unknown’’ except for Northern fur seals (Eastern Pacific stock), which is considered ‘‘declining’’ but is not listed under the ESA. Only the Guadalupe fur seal is listed under the ESA, with a population that is considered increasing. No mortality for pinnipeds is anticipated or proposed for authorization. For nearly all pinniped stocks (with the exception of the Hood Canal harbor seals) only a portion of the stocks are anticipated to be impacted and any individual is likely to be disturbed at a low-moderate level. Even considering the effects of the UMEs on the Guadalupe fur seal and California sea lion stocks, this low magnitude and severity of harassment effects is not expected to result in impacts on VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 individual reproduction or survival, much less annual rates of recruitment or survival. For the Hood Canal stock of harbor seals, a fair portion of individuals will be taken by Level B harassment (at a moderate or sometimes low level) over a comparatively higher number of days within a year, and some smaller portion of those individuals may be taken on sequential days, however this is not expected to adversely affect the stock through effects on annual rates of recruitment or survival. Accordingly, we do not anticipate the relatively small number of individual harbor seals that might be taken over repeated days within the year in a manner that results in one year of foregone reproduction to adversely affect the stock through effects on rates of recruitment or survival, given the status of the stock. For these reasons, in consideration of all of the effects of the Navy’s activities combined, we have preliminarily determined that the proposed authorized take would have a negligible impact on all stocks of pinnipeds. Preliminary Determination Based on the analysis contained herein of the likely effects of the specified activity on marine mammals and their habitat, and taking into consideration the implementation of the proposed monitoring and mitigation measures, NMFS preliminarily finds that the total marine mammal take from the Specified Activities will have a negligible impact on all affected marine mammal species or stocks. Subsistence Harvest of Marine Mammals In order to issue an incidental take authorization, NMFS must find that the specified activity will not have an ‘‘unmitigable adverse impact’’ on the subsistence uses of the affected marine mammal species or stocks by Alaskan Natives. NMFS has defined ‘‘unmitigable adverse impact’’ in 50 CFR 216.103 as an impact resulting from the specified activity: (1) That is likely to reduce the availability of the species to a level insufficient for a harvest to meet subsistence needs by: (i) Causing the marine mammals to abandon or avoid hunting areas; (ii) Directly displacing subsistence users; or (iii) Placing physical barriers between the marine mammals and the subsistence hunters; and (2) That cannot be sufficiently mitigated by other measures to increase the availability of marine mammals to allow subsistence needs to be met. To our knowledge there are no relevant subsistence uses of the affected marine mammal stocks or species PO 00000 Frm 00126 Fmt 4701 Sfmt 4702 implicated by this action. Therefore, NMFS has preliminarily determined that the total taking of affected species or stocks would not have an unmitigable adverse impact on the availability of the species or stocks for taking for subsistence purposes. However, we have limited information on marine mammal subsistence use in the Western Behm Canal area of southeastern Alaska and seek additional information pertinent to making the final determination. Classification Endangered Species Act There are seven marine mammal species under NMFS jurisdiction that are listed as endangered or threatened under the ESA with confirmed or possible occurrence in the NWTT Study Area: Blue whale, fin whale, humpback whale (Mexico and Central America DPSs), sei whale, sperm whale, killer whale (Southern Resident killer whale DPS), and Guadalupe fur seal. The Southern Resident killer whale has critical habitat designated under the ESA in the NWTT Study Area. NMFS has recently published two proposed rules, proposing new or revised ESAdesignated critical habitat for humpback whales (84 FR 54354; October 9, 2019) and Southern Resident killer whales (84 FR 49214; September 19, 2019). The Navy will consult with NMFS pursuant to section 7 of the ESA for NWTT Study Area activities. NMFS will also consult internally on the issuance of the regulations and LOAs under section 101(a)(5)(A) of the MMPA. National Marine Sanctuaries Act NMFS will work with NOAA’s Office of National Marine Sanctuaries to fulfill our responsibilities under the National Marine Sanctuaries Act as warranted and will complete any NMSA requirements prior to a determination on the issuance of the final rule and LOAs. National Environmental Policy Act To comply with the National Environmental Policy Act of 1969 (NEPA; 42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216–6A, NMFS must evaluate our proposed actions and alternatives with respect to potential impacts on the human environment. Accordingly, NMFS plans to adopt the NWTT SEIS/ OEIS for the NWTT Study Area provided our independent evaluation of the document finds that it includes adequate information analyzing the effects on the human environment of issuing regulations and LOAs under the E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules MMPA. NMFS is a cooperating agency on the 2019 NWTT DSEIS/OEIS and has worked extensively with the Navy in developing the document. The 2019 NWTT DSEIS/OEIS was made available for public comment at https:// www.nwtteis.com in April, 2019. We will review all comments submitted in response to this notice prior to concluding our NEPA process or making a final decision on the MMPA rule and request for LOAs. Regulatory Flexibility Act khammond on DSKJM1Z7X2PROD with PROPOSALS2 List of Subjects in 50 CFR Part 218 Exports, Fish, Imports, Incidental take, Indians, Labeling, Marine mammals, Navy, Penalties, Reporting and recordkeeping requirements, Seafood, Sonar, Transportation. 21:30 Jun 01, 2020 For reasons set forth in the preamble, 50 CFR part 218 is proposed to be amended as follows: PART 218—REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS 1. The authority citation for part 218 continues to read as follows: ■ The Office of Management and Budget has determined that this proposed rule is not significant for purposes of Executive Order 12866. Pursuant to the Regulatory Flexibility Act (RFA), the Chief Counsel for Regulation of the Department of Commerce has certified to the Chief Counsel for Advocacy of the Small Business Administration that this proposed rule, if adopted, would not have a significant economic impact on a substantial number of small entities. The RFA requires Federal agencies to prepare an analysis of a rule’s impact on small entities whenever the agency is required to publish a notice of proposed rulemaking. However, a Federal agency may certify, pursuant to 5 U.S.C. 605(b), that the action will not have a significant economic impact on a substantial number of small entities. The Navy is the sole entity that would be affected by this rulemaking, and the Navy is not a small governmental jurisdiction, small organization, or small business, as defined by the RFA. Any requirements imposed by an LOA issued pursuant to these regulations, and any monitoring or reporting requirements imposed by these regulations, would be applicable only to the Navy. NMFS does not expect the issuance of these regulations or the associated LOAs to result in any impacts to small entities pursuant to the RFA. Because this action, if adopted, would directly affect the Navy and not a small entity, NMFS concludes that the action would not result in a significant economic impact on a substantial number of small entities. VerDate Sep<11>2014 Dated: April 17, 2020. Samuel D. Rauch III, Deputy Assistant Administrator for Regulatory Programs,National Marine Fisheries Service. Jkt 250001 Authority: 16 U.S.C. 1361 et seq., unless otherwise noted. ■ 2. Revise subpart O to read as follows: Subpart O—Taking and Importing Marine Mammals; U.S. Navy’s Northwest Training and Testing (NWTT) Sec. 218.140 Specified activity and geographical region. 218.141 Effective dates. 218.142 Permissible methods of taking. 218.143 Prohibitions. 218.144 Mitigation requirements. 218.145 Requirements for monitoring and reporting. 218.146 Letters of Authorization. 218.147 Renewals and modifications of Letters of Authorization. 218.148 [Reserved] Subpart O—Taking and Importing Marine Mammals; U.S. Navy’s Northwest Training and Testing (NWTT) § 218.140 Specified activity and geographical region. (a) Regulations in this subpart apply only to the U.S. Navy (Navy) for the taking of marine mammals that occurs in the area described in paragraph (b) of this section and that occurs incidental to the activities listed in paragraph (c) of this section. (b) The taking of marine mammals by the Navy is only authorized if it occurs within the NWTT Study Area, which is composed of established maritime operating and warning areas in the eastern North Pacific Ocean region, including areas of the Strait of Juan de Fuca, Puget Sound, and Western Behm Canal in southeastern Alaska. The Study Area includes air and water space within and outside Washington state waters, and outside state waters of Oregon and Northern California. The eastern boundary of the Offshore Area portion of the Study Area is 12 nautical PO 00000 Frm 00127 Fmt 4701 Sfmt 4702 34039 miles (nmi) off the coastline for most of the Study Area, including southern Washington, Oregon, and Northern California. The Offshore Area includes the ocean all the way to the coastline only along that part of the Washington coast that lies beneath the airspace of W–237 and the Olympic Military Operating Area (MOA) and the Washington coastline north of the Olympic MOA. The Study Area includes four existing range complexes and facilities: The Northwest Training Range Complex (NWTRC), the Keyport Range Complex, the Carr Inlet Operations Area, and the Southeast Alaska Acoustic Measurement Facility (SEAFAC). In addition to these range complexes, the Study Area also includes Navy pierside locations where sonar maintenance and testing occurs as part of overhaul, modernization, maintenance, and repair activities at Naval Base Kitsap, Bremerton; Naval Base Kitsap, Bangor; and Naval Station Everett. (c) The taking of marine mammals by the Navy is only authorized if it occurs incidental to the Navy conducting training and testing activities, including: (1) Anti-submarine warfare; (2) Expeditionary warfare; (3) Mine warfare; (4) Surface warfare; and (5) Other training and testing activities. § 218.141 Effective dates. Regulations in this subpart are effective from November 9, 2020 through November 8, 2027. § 218.142 Permissible methods of taking. (a) Under Letters of Authorization (LOAs) issued pursuant to §§ 216.106 of this chapter and 218.146, the Holder of the LOAs (hereinafter ‘‘Navy’’) may incidentally, but not intentionally, take marine mammals within the area described in § 218.140(b) by Level A harassment and Level B harassment associated with the use of active sonar and other acoustic sources and explosives, as well as serious injury or mortality associated with vessel strikes, provided the activity is in compliance with all terms, conditions, and requirements of this subpart and the applicable LOAs. (b) The incidental take of marine mammals by the activities listed in § 218.140(c) is limited to the following species: E:\FR\FM\02JNP2.SGM 02JNP2 34040 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules TABLE 1 TO § 218.142 Species Stock Blue whale ................................................................................................ Fin whale .................................................................................................. Fin whale .................................................................................................. Sei whale .................................................................................................. Minke whale .............................................................................................. Minke whale .............................................................................................. Humpback whale ...................................................................................... Humpback whale ...................................................................................... Gray whale ............................................................................................... Bottlenose dolphin .................................................................................... Killer whale ............................................................................................... Killer whale ............................................................................................... Killer whale ............................................................................................... Killer whale ............................................................................................... Northern right whale dolphin .................................................................... Pacific white-sided dolphin ....................................................................... Pacific white-sided dolphin ....................................................................... Risso’s dolphin ......................................................................................... Short-beaked common dolphin ................................................................ Short-finned pilot whale ............................................................................ Striped dolphin .......................................................................................... Pygmy sperm whale ................................................................................. Dwarf sperm whale ................................................................................... Dall’s porpoise .......................................................................................... Dall’s porpoise .......................................................................................... Harbor porpoise ........................................................................................ Harbor porpoise ........................................................................................ Harbor porpoise ........................................................................................ Harbor porpoise ........................................................................................ Sperm whale ............................................................................................. Baird’s beaked whale ............................................................................... Cuvier’s beaked whale ............................................................................. Mesoplodon species ................................................................................. California sea lion ..................................................................................... Steller sea lion .......................................................................................... Guadalupe fur seal ................................................................................... Northern fur seal ....................................................................................... Northern fur seal ....................................................................................... Harbor seal ............................................................................................... Harbor seal ............................................................................................... Harbor seal ............................................................................................... Harbor seal ............................................................................................... Harbor seal ............................................................................................... Northern elephant seal ............................................................................. khammond on DSKJM1Z7X2PROD with PROPOSALS2 § 218.143 Prohibitions. § 218.144 Notwithstanding incidental takings contemplated in § 218.142(a) and authorized by LOAs issued under §§ 216.106 of this chapter and 218.146, no person in connection with the activities listed in § 218.140(c) may: (a) Violate, or fail to comply with, the terms, conditions, and requirements of this subpart or an LOA issued under §§ 216.106 of this chapter and 218.146; (b) Take any marine mammal not specified in § 218.142(b); (c) Take any marine mammal specified in § 218.142(b) in any manner other than as specified in the LOAs; or (d) Take a marine mammal specified in § 218.142(b) if NMFS determines such taking results in more than a negligible impact on the species or stocks of such marine mammal. VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 Eastern North Pacific. Northeast Pacific. California/Oregon/Washington. Eastern North Pacific. Alaska. California/Oregon/Washington. Central North Pacific. California/Oregon/Washington. Eastern North Pacific. California/Oregon/Washington Offshore. Alaska Resident. Eastern North Pacific Offshore. West Coast Transient. Southern Resident. California/Oregon/Washington. North Pacific. California/Oregon/Washington. California/Oregon/Washington. California/Oregon/Washington. California/Oregon/Washington. California/Oregon/Washington. California/Oregon/Washington. California/Oregon/Washington. Alaska. California/Oregon/Washington. Southeast Alaska. Northern Oregon & Washington Coast. Northern California/Southern Oregon. Washington Inland Waters. California/Oregon/Washington. California/Oregon/Washington. California/Oregon/Washington. California/Oregon/Washington. U.S. Stock. Eastern U.S. Mexico. Eastern Pacific. California. Southeast Alaska—Clarence Strait. Oregon & Washington Coastal. Washington Northern Inland Waters. Hood Canal. Southern Puget Sound. California. Mitigation requirements. When conducting the activities identified in § 218.140(c), the mitigation measures contained in any LOAs issued under §§ 216.106 of this chapter and 218.146 must be implemented. These mitigation measures include, but are not limited to: (a) Procedural mitigation. Procedural mitigation is mitigation that the Navy must implement whenever and wherever an applicable training or testing activity takes place within the NWTT Study Area for acoustic stressors (i.e., active sonar, weapons firing noise), explosive stressors (i.e., sonobuoys, torpedoes, medium-caliber and largecaliber projectiles, missiles, bombs, mine countermeasure and neutralization activities, mine neutralization involving Navy divers), and physical disturbance and strike stressors (i.e., vessel PO 00000 Frm 00128 Fmt 4701 Sfmt 4702 movement, towed in-water devices, small-, medium-, and large-caliber nonexplosive practice munitions, nonexplosive missiles, non-explosive bombs and mine shapes). (1) Environmental awareness and education. Appropriate Navy personnel (including civilian personnel) involved in mitigation and training or testing activity reporting under the specified activities will complete one or more modules of the U.S Navy Afloat Environmental Compliance Training Series, as identified in their career path training plan. Modules include: Introduction to the U.S. Navy Afloat Environmental Compliance Training Series; Marine Species Awareness Training; U.S. Navy Protective Measures Assessment Protocol; and U.S. Navy Sonar Positional Reporting System and Marine Mammal Incident Reporting. E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules (2) Active sonar. Active sonar includes low-frequency active sonar, mid-frequency active sonar, and highfrequency active sonar. For vessel-based activities, mitigation applies only to sources that are positively controlled and deployed from manned surface vessels (e.g., sonar sources towed from manned surface platforms). For aircraftbased activities, mitigation applies only to sources that are positively controlled and deployed from manned aircraft that do not operate at high altitudes (e.g., rotary-wing aircraft). Mitigation does not apply to active sonar sources deployed from unmanned aircraft or aircraft operating at high altitudes (e.g., maritime patrol aircraft). (i) Number of Lookouts and observation platform—(A) For hullmounted sources, one Lookout for platforms with space or manning restrictions while underway (at the forward part of a small boat or ship) and platforms using active sonar while moored or at anchor (including pierside); and two Lookouts for platforms without space or manning restrictions while underway (at the forward part of the ship). (B) For sources that are not hull mounted, One Lookout on the ship or aircraft conducting the activity. (ii) Mitigation zone and requirements. (A) Prior to the initial start of the activity (e.g., when maneuvering on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammals is observed, Navy personnel must relocate or delay the start of active sonar transmission until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(2)(ii)(D) of this section are met for marine mammals. (B) During the activity, for lowfrequency active sonar at or above 200 dB and hull-mounted mid-frequency active sonar, Navy personnel must observe the mitigation zone for marine mammals. If a marine mammal is observed within 1,000 yd of the sonar source, Navy personnel must power down active sonar transmission by 6 dB. If a marine mammal is observed within 500 yd of the sonar source, Navy personnel must power down active sonar transmission an additional 4 dB (10 dB total). Navy personnel must cease transmission if a cetacean or pinniped in the NWTT Offshore Area or Western Behm Canal is observed within 200 yd of the active sonar source and must cease transmission if a pinniped in NWTT Inland Waters is observed within 100 yd of the active sonar source (except VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 if hauled out on, or in the water near, man-made structures and vessels). (C) During the activity, for lowfrequency active sonar below 200 dB, mid-frequency active sonar sources that are not hull-mounted, and highfrequency sonar, Navy personnel must observe the mitigation zone for marine mammals. Navy personnel must cease transmission if a cetacean in the NWTT Offshore Area, NWTT Inshore Area, or Western Behm Canal is observed within 200 yd of the sonar source. Navy personnel must cease transmission if a pinniped in the NWTT Offshore Area or Western Behm Canal is observed within 200 yd of the sonar source and must cease transmission if a pinniped in NWTT Inland Waters is observed within 100 yd of the active sonar source (except if hauled out on, or in the water near, man-made structures and vessels). (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing or powering up active sonar transmission) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the sonar source; the mitigation zone has been clear from any additional sightings for 10 minutes (min) for aircraft-deployed sonar sources or 30 min for vessel-deployed sonar sources; for mobile activities, the active sonar source has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting; or for activities using hull-mounted sonar where a dolphin(s) is observed in the mitigation zone, the Lookout concludes that the dolphin(s) is deliberately closing in on the ship to ride the ship’s bow wave, and are therefore out of the main transmission axis of the sonar (and there are no other marine mammal sightings within the mitigation zone). (3) Weapons firing noise. Weapons firing noise associated with large-caliber gunnery activities. (i) Number of Lookouts and observation platform. One Lookout must be positioned on the ship conducting the firing. Depending on the activity, the Lookout could be the same as the one provided for under ‘‘Explosive mediumcaliber and large-caliber projectiles’’ or under ‘‘Small-, medium-, and largecaliber non-explosive practice PO 00000 Frm 00129 Fmt 4701 Sfmt 4702 34041 munitions’’ in paragraphs (a)(6)(i) and (a)(13)(i) of this section. (ii) Mitigation zone and requirements. (A) Thirty degrees on either side of the firing line out to 70 yd from the muzzle of the weapon being fired. (B) Prior to the initial start of the activity, Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of weapons firing until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(3)(ii)(D) of this section are met for marine mammals. (C) During the activity, Navy personnel must observe the mitigation zone for marine mammals; if marine mammals are observed, Navy personnel must cease weapons firing. (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing weapons firing) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the firing ship; the mitigation zone has been clear from any additional sightings for 30 min; or for mobile activities, the firing ship has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. (4) Explosive sonobuoys—(i) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft or on a small boat. If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for applicable biological resources while performing their regular duties. (ii) Mitigation zone and requirements. (A) 600 yd around an explosive sonobuoy. (B) Prior to the initial start of the activity (e.g., during deployment of a sonobuoy field, which typically lasts 20–30 min), Navy personnel must conduct passive acoustic monitoring for marine mammals and use information from detections to assist visual observations. Navy personnel also must visually observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 34042 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules marine mammal is observed, Navy personnel must relocate or delay the start of sonobuoy or source/receiver pair detonations until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(4)(ii)(D) of this section are met for marine mammals. (C) During the activity, Navy personnel must observe the mitigation zone for marine mammals; if marine mammals are observed, Navy personnel must cease sonobuoy or source/receiver pair detonations. (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing detonations) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the sonobuoy; or the mitigation zone has been clear from any additional sightings for 10 min when the activity involves aircraft that have fuel constraints, or 30 min when the activity involves aircraft that are not typically fuel constrained. (E) After completion of the activity (e.g., prior to maneuvering off station), Navy personnel must, when practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), these Navy assets must assist in the visual observation of the area where detonations occurred. (5) Explosive torpedoes—(i) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft. If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties. (ii) Mitigation zone and requirements. (A) 2,100 yd around the intended impact location. (B) Prior to the initial start of the activity (e.g., during deployment of the target), Navy personnel must conduct passive acoustic monitoring for marine VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 mammals and use the information from detections to assist visual observations. Navy personnel also must visually observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of firing until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(5)(ii)(D) of this section are met for marine mammals. (C) During the activity, Navy personnel must observe the mitigation zone for marine mammals. If a marine mammal is observed, Navy personnel must cease firing. (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; or the mitigation zone has been clear from any additional sightings for 10 min when the activity involves aircraft that have fuel constraints, or 30 min when the activity involves aircraft that are not typically fuel constrained. (E) After completion of the activity (e.g., prior to maneuvering off station), Navy personnel must, when practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), these Navy assets must assist in the visual observation of the area where detonations occurred. (6) Explosive medium-caliber and large-caliber projectiles. Gunnery activities using explosive mediumcaliber and large-caliber projectiles. Mitigation applies to activities using a surface target. (i) Number of Lookouts and observation platform. One Lookout must be on the vessel conducting the activity. For activities using explosive largecaliber projectiles, depending on the activity, the Lookout could be the same as the one described in ‘‘Weapons firing PO 00000 Frm 00130 Fmt 4701 Sfmt 4702 noise’’ in paragraph (a)(3)(i) of this section. If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties. (ii) Mitigation zone and requirements. (A) 600 yd around the intended impact location for explosive medium-caliber projectiles. (B) 1,000 yd around the intended impact location for explosive largecaliber projectiles. (C) Prior to the initial start of the activity (e.g., when maneuvering on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of firing until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(6)(ii)(E) are met for marine mammals. (D) During the activity, Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease firing. (E) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; the mitigation zone has been clear from any additional sightings for 30 min for vessel-based firing; or, for activities using mobile targets, the intended impact location has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. (F) After completion of the activity (e.g., prior to maneuvering off station), Navy personnel must, when practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules these Navy assets must assist in the visual observation of the area where detonations occurred. (7) Explosive missiles. Aircraftdeployed explosive missiles. Mitigation applies to activities using a surface target. (i) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft. If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties. (ii) Mitigation zone and requirements. (A) 2,000 yd around the intended impact location. (B) Prior to the initial start of the activity (e.g., during a fly-over of the mitigation zone), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of firing until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(7)(ii)(D) are met for marine mammals. (C) During the activity, Navy personnel must observe the mitigation zone for marine mammals; if marine mammals are observed, Navy personnel must cease firing. (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; or the mitigation zone has been clear from any additional sightings for 10 min when the activity involves aircraft that have fuel constraints, or 30 min when the activity involves aircraft that are not typically fuel constrained. (E) After completion of the activity (e.g., prior to maneuvering off station), Navy personnel must, when practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, Navy personnel must follow established VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), these Navy assets must assist in the visual observation of the area where detonations occurred. (8) Explosive bombs—(i) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft conducting the activity. If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties. (ii) Mitigation zone and requirements. (A) 2,500 yd around the intended target. (B) Prior to the initial start of the activity (e.g., when arriving on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammals is observed, Navy personnel must relocate or delay the start of bomb deployment until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(8)(ii)(D) of this section are met for marine mammals. (C) During the activity (e.g., during target approach), Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease bomb deployment. (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing bomb deployment) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended target; the mitigation zone has been clear from any additional sightings for 10 min; or for activities using mobile targets, the intended target has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. (E) After completion of the activity (e.g., prior to maneuvering off station), Navy personnel must, when practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, PO 00000 Frm 00131 Fmt 4701 Sfmt 4702 34043 Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), these Navy assets must assist in the visual observation of the area where detonations occurred. (9) Explosive mine countermeasure and neutralization activities—(i) Number of Lookouts and observation platform. (A) One Lookout must be positioned on a vessel or in an aircraft when implementing the smaller mitigation zone. (B) Two Lookouts must be positioned (one in an aircraft and one on a small boat) when implementing the larger mitigation zone. (C) If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties. (ii) Mitigation zone and requirements. (A) 600 yd around the detonation site for activities using ≤5 lb net explosive weight. (B) 2,100 yd around the detonation site for activities using >5–60 lb net explosive weight. (C) Prior to the initial start of the activity (e.g., when maneuvering on station; typically, 10 min when the activity involves aircraft that have fuel constraints, or 30 min when the activity involves aircraft that are not typically fuel constrained), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of detonations until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (ii)(E) are met for marine mammals. (D) During the activity, Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease detonations. (E) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing detonations) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to detonation site; or the mitigation zone has been clear from E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 34044 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules any additional sightings for 10 min when the activity involves aircraft that have fuel constraints, or 30 min when the activity involves aircraft that are not typically fuel constrained. (F) After completion of the activity (typically 10 min when the activity involves aircraft that have fuel constraints, or 30 min when the activity involves aircraft that are not typically fuel constrained), Navy personnel must observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), these Navy assets must assist in the visual observation of the area where detonations occurred. (10) Explosive mine neutralization activities involving Navy divers—(i) Number of Lookouts and observation platform. (A) Two Lookouts (two small boats with one Lookout each (one of which must be a Navy biologist)). (B) All divers placing the charges on mines must support the Lookouts while performing their regular duties and will report applicable sightings to their supporting small boat or Range Safety Officer. (C) If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties. (ii) Mitigation zone and requirements. (A) 500 yd around the detonation site during activities using >0.5–2.5 lb net explosive weight. (B) Prior to the initial start of the activity (e.g., starting 30 min before the first planned detonation), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation is observed, Navy personnel must relocate or delay the start of detonations until the mitigation zone is clear of floating vegetation. If a marine mammal is observed, Navy personnel must ensure the area is clear of marine mammals for 30 min prior to commencing a detonation. A Navy biologist must serve as the lead Lookout and must make the final determination that the mitigation zone is clear of any floating vegetation or marine mammals prior to the commencement of a detonation. The Navy biologist must maintain radio communication with the unit conducting the event and the other Lookout. (C) During the activity, Navy personnel must observe the mitigation VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 zone for marine mammals; if a marine mammal is observed, Navy personnel must cease detonations. To the maximum extent practicable depending on mission requirements, safety, and environmental conditions, Navy personnel must position boats near the midpoint of the mitigation zone radius (but outside of the detonation plume and human safety zone), must position themselves on opposite sides of the detonation location (when two boats are used), and must travel in a circular pattern around the detonation location with one Lookout observing inward toward the detonation site and the other observing outward toward the perimeter of the mitigation zone. Navy personnel must only use positively controlled charges (i.e., no time-delay fuses). Navy personnel must use the smallest practicable charge size for each activity. All activities must be conducted in Beaufort sea state number 2 conditions or better and must not be conducted in low visibility conditions. (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted animal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing detonations) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the detonation site; or the mitigation zone has been clear from any additional sightings for 30 min. (E) After each detonation and completion of an activity the Navy must observe for marine mammals for 30 min Navy personnel must observe for marine mammals in the vicinity of where detonations occurred and immediately downstream of the detonation location; if any injured or dead marine mammals are observed, Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), these Navy assets must assist in the visual observation of the area where detonations occurred. (F) At the Hood Canal Explosive Ordnance Disposal Range and Crescent Harbor Explosive Ordnance Disposal Range, Navy personnel must obtain permission from the appropriate designated Command authority prior to conducting explosive mine neutralization activities involving the use of Navy divers. PO 00000 Frm 00132 Fmt 4701 Sfmt 4702 (G) At the Hood Canal Explosive Ordnance Disposal Range, during February, March, and April (the juvenile migration period for Hood Canal Summer Run Chum), Navy personnel must not use explosives in bin E3 (>0.5– 2.5 lb net explosive weight), and must instead use explosives in bin E0 (<0.1 lb net explosive weight). (H) At the Hood Canal Explosive Ordnance Disposal Range, during August, September, and October (the adult migration period for Hood Canal summer-run chum and Puget Sound Chinook), Navy personnel must avoid the use of explosives in bin E3 (>0.5–2.5 lb net explosive weight), and must instead use explosive bin E0 (<0.1 lb net explosive weight) to the maximum extent practicable unless necessitated by mission requirements. (I) At the Crescent Harbor Explosive Ordnance Disposal Range, Navy personnel must conduct explosive activities at least 1,000 meters (m) from the closest point of land to avoid or reduce impacts on fish (e.g., bull trout) in nearshore habitat areas. (11) Vessel movement. The mitigation will not be applied if: The vessel’s safety is threatened; the vessel is restricted in its ability to maneuver (e.g., during launching and recovery of aircraft or landing craft, during towing activities, when mooring, during Transit Protection Program exercises, and other events involving escort vessels); the vessel is operated autonomously; or when impractical based on mission requirements (e.g., during test body retrieval by range craft). (i) Number of Lookouts and observation platform. One Lookout must be on the vessel that is underway. (ii) Mitigation zone and requirements. (A) 500 yd around whales for surface vessels other than small boats. (B) 200 yd around all marine mammals other than whales (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels) for surface vessels other than small boats. (C) 100 yd around marine mammals (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels) for small boats, such as range craft. (D) During the activity (when underway), Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must maneuver to maintain distance. (E) Prior to Small Boat Attack exercises at Naval Station Everett, Naval Base Kitsap Bangor, or Naval Base E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Kitsap Bremerton, Navy event planners must coordinate with Navy biologists during the event planning process. Navy biologists must work with NMFS to determine the likelihood of marine mammal presence in the planned training location. Navy biologists must notify event planners of the likelihood of species presence as they plan specific details of the event (e.g., timing, location, duration). Navy personnel must provide additional environmental awareness training to event participants. The training must alert participating ship crews to the possible presence of marine mammals in the training location. Lookouts must use the information to assist their visual observation of applicable mitigation zones and to aid in the implementation of procedural mitigation. (iii) Incident reporting procedures. If a marine mammal vessel strike occurs, Navy personnel must follow the established incident reporting procedures. (12) Towed in-water devices. Mitigation applies to devices that are towed from a manned surface platform or manned aircraft, or when a manned support craft is already participating in an activity involving in-water devices being towed by unmanned platforms. The mitigation will not be applied if the safety of the towing platform or in-water device is threatened. (i) Number of Lookouts and observation platform. One Lookout must be positioned on a manned towing platform or support craft. (ii) Mitigation zone and requirements. (A) 250 yd around marine mammals (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels) for in-water devices towed by aircraft or surface vessels other than small boats. (B) 100 yd around marine mammals (except bow-riding dolphins and pinnipeds hauled out on man-made navigational structures, port structures, and vessels) for in-water devices towed by small boats, such as range craft. (C) During the activity (i.e., when towing an in-water device), Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must maneuver to maintain distance. (13) Small-, medium-, and largecaliber non-explosive practice munitions. Gunnery activities using small-, medium-, and large-caliber nonexplosive practice munitions. Mitigation applies to activities using a surface target. (i) Number of Lookouts and observation platform. One Lookout must VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 be positioned on the platform conducting the activity. Depending on the activity, the Lookout could be the same as the one described for ‘‘Weapons firing noise’’ in paragraph (a)(3)(i) of this section. (ii) Mitigation zone and requirements. (A) 200 yd around the intended impact location. (B) Prior to the initial start of the activity (e.g., when maneuvering on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(13)(ii)(D) of this section are met for marine mammals. (C) During the activity, Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease firing. (D) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; the mitigation zone has been clear from any additional sightings for 10 min for aircraft-based firing or 30 min for vessel-based firing; or for activities using a mobile target, the intended impact location has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. (14) Non-explosive missiles. Aircraftdeployed non-explosive missiles. Mitigation applies to activities using a surface target. (i) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft. (ii) Mitigation zone and requirements. (A) 900 yd around the intended impact location. (B) Prior to the initial start of the activity (e.g., during a fly-over of the mitigation zone), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of firing until the mitigation zone is clear of floating PO 00000 Frm 00133 Fmt 4701 Sfmt 4702 34045 vegetation or until the conditions in paragraph (a)(14)(ii)(D) of this section are met for marine mammals. (C) During the activity, Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease firing. (D) Commencement/recommencement conditions after a marine mammal sighting prior to or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met: The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location; or the mitigation zone has been clear from any additional sightings for 10 min when the activity involves aircraft that have fuel constraints, or 30 min when the activity involves aircraft that are not typically fuel constrained. (15) Non-explosive bombs and mine shapes. Non-explosive bombs and nonexplosive mine shapes during mine laying activities. (i) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft. (ii) Mitigation zone and requirements. (A) 1,000 yd around the intended target. (B) Prior to the initial start of the activity (e.g., when arriving on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of bomb deployment or mine laying until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(15)(ii)(D) of section are met for marine mammals. (C) During the activity (e.g., during approach of the target or intended minefield location), Navy personnel must observe the mitigation zone for marine mammals and, if a marine mammal is observed, Navy personnel must cease bomb deployment or mine laying. (D) Commencement/recommencement conditions after a marine mammal sighting prior to or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing bomb deployment or mine laying) until one of the following conditions has been met: E:\FR\FM\02JNP2.SGM 02JNP2 khammond on DSKJM1Z7X2PROD with PROPOSALS2 34046 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules The animal is observed exiting the mitigation zone; the animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended target or minefield location; the mitigation zone has been clear from any additional sightings for 10 min; or for activities using mobile targets, the intended target has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting. (b) Mitigation areas. In addition to procedural mitigation, Navy personnel must implement mitigation measures within mitigation areas to avoid or reduce potential impacts on marine mammals. (1) Mitigation areas for marine mammals for NWTT Study Area for sonar, explosives, and physical disturbance and vessel strikes—(i) Mitigation area requirements—(A) Marine Species Coastal Mitigation Area (year round). (1) Within 50 nmi from shore in the Marine Species Coastal Mitigation Area, Navy personnel must not conduct: Explosive training activities; explosive testing activities (with the exception of explosive Mine Countermeasure and Neutralization Testing activities); and non-explosive missile training activities. Should national security require conducting these activities in the mitigation area, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (2) Within 20 nmi from shore in the Marine Species Coastal Mitigation Area, Navy personnel must not conduct nonexplosive large-caliber gunnery training activities and non-explosive bombing training activities. Should national security require conducting these activities in the mitigation area, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (3) Within 12 nmi from shore in the Marine Species Coastal Mitigation Area, Navy personnel must not conduct: Nonexplosive small- and medium-caliber gunnery training activities; nonexplosive torpedo training activities; and Anti-Submarine Warfare Tracking Exercise—Helicopter, Maritime Patrol Aircraft, Ship, or Submarine training activities. Should national security VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 require conducting these activities in the mitigation area, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (B) Olympic Coast National Marine Sanctuary Mitigation Area (year-round). (1) Within the Olympic Coast National Marine Sanctuary Mitigation Area, Navy personnel must not conduct more than 32 hours of MF1 mid-frequency active sonar during training annually and will not conduct non-explosive bombing training activities. Should national security require conducting more than 32 hours of MF1 mid-frequency active sonar during training annually or conducting non-explosive bombing training activities in the mitigation area, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (2) Within the Olympic Coast National Marine Sanctuary Mitigation Area, Navy personnel must not conduct more than 33 hours of MF1 midfrequency active sonar during testing annually (except within the portion of the mitigation area that overlaps the Quinault Range Site) and must not conduct explosive Mine Countermeasure and Neutralization Testing activities. Should national security require conducting more than 33 hours of MF1 mid-frequency active sonar during testing annually (except within the portion of the mitigation area that overlaps the Quinault Range Site) or conducting explosive Mine Countermeasure and Neutralization Testing activities in the mitigation area, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (C) Stonewall and Heceta Bank Humpback Whale Mitigation Area (May 1–November 30). Within the Stonewall and Heceta Bank Humpback Whale Mitigation Area, Navy personnel must not use MF1 mid-frequency active sonar or explosives during training and testing from May 1 to November 30. Should national security require using MF1 mid-frequency active sonar or explosives during training and testing PO 00000 Frm 00134 Fmt 4701 Sfmt 4702 from May 1 to November 30, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (D) Point St. George Humpback Whale Mitigation Area (July 1–November 30). Within the Point St. George Humpback Whale Mitigation Area, Navy personnel must not use MF1 mid-frequency active sonar or explosives during training and testing from July 1 to November 30. Should national security require using MF1 mid-frequency active sonar or explosives during training and testing from July 1 to November 30, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (E) Puget Sound and Strait of Juan de Fuca Mitigation Area (year-round). (1) Within the Puget Sound and Strait of Juan de Fuca Mitigation Area, Navy personnel must obtain approval from the appropriate designated Command authority prior to: The use of hullmounted mid-frequency active sonar during training while underway or conducting ship and submarine active sonar pierside maintenance or testing. (2) Within the Puget Sound and Strait of Juan de Fuca Mitigation Area for Civilian Port Defense—Homeland Security Anti-Terrorism/Force Protection Exercises, Navy personnel must coordinate with Navy biologists during the event planning process. Navy biologists must work with NMFS to determine the likelihood of gray whale and Southern Resident Killer Whale presence in the planned training location. Navy biologists must notify Navy event planners of the likelihood of species presence as they plan specific details of the event (e.g., timing, location, duration). Navy personnel must ensure environmental awareness of event participants. Environmental awareness will help alert participating ship and aircraft crews to the possible presence of marine mammals in the training location, such as gray whales and Southern Resident Killer Whales. (F) Northern Puget Sound Gray Whale Mitigation Area (March 1–May 31). Within the Northern Puget Sound Gray Whale Mitigation Area, Navy personnel must not conduct Civilian Port Defense—Homeland Security AntiTerrorism/Force Protection Exercises from March 1 to May 31. Should national security require conducting E:\FR\FM\02JNP2.SGM 02JNP2 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules Civilian Port Defense—Homeland Security Anti-Terrorism/Force Protection Exercises from March 1 to May 31, Navy personnel must obtain permission from the appropriate designated Command authority prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS. (ii) [Reserved] khammond on DSKJM1Z7X2PROD with PROPOSALS2 § 218.145 Requirements for monitoring and reporting. (a) Unauthorized take. Navy personnel must notify NMFS immediately (or as soon as operational security considerations allow) if the specified activity identified in § 218.140 is thought to have resulted in the mortality or serious injury of any marine mammals, or in any Level A harassment or Level B harassment of marine mammals not identified in this subpart. (b) Monitoring and reporting under the LOAs. The Navy must conduct all monitoring and reporting required under the LOAs, including abiding by the U.S. Navy’s Marine Species Monitoring Program. Details on program goals, objectives, project selection process, and current projects are available at www.navymarinespeciesmonitoring.us. (c) Notification of injured, live stranded, or dead marine mammals. The Navy must consult the Notification and Reporting Plan, which sets out notification, reporting, and other requirements when dead, injured, or live stranded marine mammals are detected. The Notification and Reporting Plan is available at https:// www.fisheries.noaa.gov/national/ marine-mammal-protection/incidentaltake-authorizations-military-readinessactivities. (d) Annual NWTT Study Area marine species monitoring report. The Navy must submit an annual report of the NWTT Study Area monitoring describing the implementation and results from the previous calendar year. Data collection methods must be standardized across range complexes and study areas to allow for comparison in different geographic locations. The report must be submitted to the Director, Office of Protected Resources, NMFS, either within three months after the end of the calendar year, or within three months after the conclusion of the monitoring year, to be determined by the Adaptive Management process. NMFS will submit comments or questions on the report, if any, within one month of receipt. The report will be considered final after the Navy has VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 addressed NMFS’ comments, or one month after submittal of the draft if NMFS does not provide comments on the draft report. This report will describe progress of knowledge made with respect to intermediate scientific objectives within the NWTT Study Area associated with the Integrated Comprehensive Monitoring Program (ICMP). Similar study questions must be treated together so that progress on each topic can be summarized across all Navy ranges. The report need not include analyses and content that does not provide direct assessment of cumulative progress on the monitoring plan study questions. As an alternative, the Navy may submit a multi-range complex annual monitoring plan report to fulfill this requirement. Such a report will describe progress of knowledge made with respect to monitoring study questions across multiple Navy ranges associated with the ICMP. Similar study questions must be treated together so that progress on each topic can be summarized across multiple Navy ranges. The report need not include analyses and content that does not provide direct assessment of cumulative progress on the monitoring study question. This will continue to allow the Navy to provide a cohesive monitoring report covering multiple ranges (as per ICMP goals), rather than entirely separate reports for the NWTT, Hawaii-Southern California, Gulf of Alaska, and Mariana Islands Study Areas. (e) Annual NWTT Study Area training exercise report and testing activity reports. Each year, the Navy must submit two preliminary reports (Quick Look Report) detailing the status of applicable sound sources within 21 days after the anniversary of the date of issuance of each LOA to the Director, Office of Protected Resources, NMFS. Each year, the Navy must submit a detailed report to the Director, Office of Protected Resources, NMFS, within three months after the one-year anniversary of the date of issuance of the LOA. NMFS will submit comments or questions on the report, if any, within one month of receipt. The report will be considered final after the Navy has addressed NMFS’ comments, or one month after submittal of the draft if NMFS does not provide comments on the draft report. The NWTT Annual Training Exercise Report and Testing Activity Report can be consolidated with other exercise reports from other range complexes in the Pacific Ocean for a single Pacific Exercise Report, if desired. The annual report must contain information on the total hours of PO 00000 Frm 00135 Fmt 4701 Sfmt 4702 34047 operation of MF1 surface ship hullmounted mid-frequency active sonar used during training and testing activities in the Olympic Coast National Marine Sanctuary Mitigation Area and a summary of all sound sources used, including within specific mitigation reporting areas as described in paragraph (e)(2) of this section. The analysis in the detailed report must be based on the accumulation of data from the current year’s report and data collected from previous annual reports. The annual report will also contain cumulative sonar and explosive use quantity from previous years’ reports through the current year. Additionally, if there were any changes to the sound source allowance in a given year, or cumulatively, the report must include a discussion of why the change was made and include analysis to support how the change did or did not affect the analysis in the NWTT SEIS/OEIS and MMPA final rule. The annual report must also include details regarding specific requirements associated with the mitigation areas listed in § 218.144(b). The analysis in the detailed report will be based on the accumulation of data from the current year’s report and data collected from previous reports. The final annual/close-out report at the conclusion of the authorization period (year seven) will serve as the comprehensive close-out report and include both the final year annual incidental take compared to annual authorized incidental take as well as a cumulative seven-year incidental take compared to seven-year authorized incidental take. The detailed reports must contain information identified in paragraphs (e)(1) through (3) of this section. (1) Summary of sources used. This section of the report must include the following information summarized from the authorized sound sources used in all training and testing events: (i) Total annual hours or quantity (per the LOA) of each bin of sonar and other transducers, and (ii) Total annual expended/detonated ordinance (missiles, bombs, sonobuoys, etc.) for each explosive bin. (2) NWTT Study Area Mitigation Areas. The report must include any Navy activities that occurred as specifically described in areas identified in § 218.144(b). Information included in the classified annual reports may be used to inform future adaptive management of activities within the NWTT Study Area. (3) Geographic information presentation. The reports must present an annual (and seasonal, where practical) depiction of training and E:\FR\FM\02JNP2.SGM 02JNP2 34048 Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 / Proposed Rules testing bin usage geographically across the NWTT Study Area. (f) Seven-year close-out report. The final (year seven) draft annual/close-out report must be submitted within three months after the expiration of this subpart to the Director, Office of Protected Resources, NMFS. NMFS will submit comments on the draft close-out report, if any, within three months of receipt. The report will be considered final after the Navy has addressed NMFS’ comments, or three months after submittal of the draft if NMFS does not provide comments on the draft report. § 218.146 Letters of Authorization. khammond on DSKJM1Z7X2PROD with PROPOSALS2 (a) To incidentally take marine mammals pursuant to this subpart, the Navy must apply for and obtain an LOA in accordance with § 216.106 of this chapter. (b) An LOA, unless suspended or revoked, may be effective for a period of time not to exceed the expiration date of this subpart. (c) If an LOA expires prior to the expiration date of this subpart, the Navy may apply for and obtain a renewal of the LOA. (d) In the event of projected changes to the activity or to mitigation, monitoring, or reporting (excluding changes made pursuant to the adaptive management provision of § 218.147(c)(1)) required by an LOA issued under this subpart, the Navy must apply for and obtain a modification of the LOA as described in § 218.147. (e) Each LOA will set forth: (1) Permissible methods of incidental taking; (2) Geographic areas for incidental taking; (3) Means of effecting the least practicable adverse impact (i.e., mitigation) on the species and stocks of marine mammals and their habitat; and VerDate Sep<11>2014 21:30 Jun 01, 2020 Jkt 250001 (4) Requirements for monitoring and reporting. (f) Issuance of the LOA(s) will be based on a determination that the level of taking is consistent with the findings made for the total taking allowable under this subpart. (g) Notice of issuance or denial of the LOA(s) will be published in the Federal Register within 30 days of a determination. § 218.147 Renewals and modifications of Letters of Authorization. (a) An LOA issued under §§ 216.106 of this chapter and 218.146 for the activity identified in § 218.140(c) may be renewed or modified upon request by the applicant, provided that: (1) The planned specified activity and mitigation, monitoring, and reporting measures, as well as the anticipated impacts, are the same as those described and analyzed for this subpart (excluding changes made pursuant to the adaptive management provision in paragraph (c)(1) of this section); and (2) NMFS determines that the mitigation, monitoring, and reporting measures required by the previous LOA(s) were implemented. (b) For LOA modification or renewal requests by the applicant that include changes to the activity or to the mitigation, monitoring, or reporting measures (excluding changes made pursuant to the adaptive management provision in paragraph (c)(1) of this section) that do not change the findings made for this subpart or result in no more than a minor change in the total estimated number of takes (or distribution by species or stock or years), NMFS may publish a notice of planned LOA in the Federal Register, including the associated analysis of the change, and solicit public comment before issuing the LOA. PO 00000 Frm 00136 Fmt 4701 Sfmt 9990 (c) An LOA issued under §§ 216.106 of this chapter and 218.146 may be modified by NMFS under the following circumstances: (1) Through Adaptive Management, after consulting with the Navy regarding the practicability of the modifications, NMFS may modify (including adding or removing measures) the existing mitigation, monitoring, or reporting measures if doing so creates a reasonable likelihood of more effectively accomplishing the goals of the mitigation and monitoring. (i) Possible sources of data that could contribute to the decision to modify the mitigation, monitoring, or reporting measures in an LOA include: (A) Results from the Navy’s monitoring from the previous year(s); (B) Results from other marine mammal and/or sound research or studies; or (C) Any information that reveals marine mammals may have been taken in a manner, extent, or number not authorized by this subpart or subsequent LOAs. (ii) If, through adaptive management, the modifications to the mitigation, monitoring, or reporting measures are substantial, NMFS will publish a notice of planned LOA in the Federal Register and solicit public comment. (2) If NMFS determines that an emergency exists that poses a significant risk to the well-being of the species or stocks of marine mammals specified in LOAs issued pursuant to §§ 216.106 of this chapter and 218.146, an LOA may be modified without prior notice or opportunity for public comment. Notice would be published in the Federal Register within thirty days of the action. § 218.148 [Reserved] [FR Doc. 2020–08533 Filed 5–22–20; 11:15 am] BILLING CODE 3510–22–P E:\FR\FM\02JNP2.SGM 02JNP2

Agencies

[Federal Register Volume 85, Number 106 (Tuesday, June 2, 2020)]
[Proposed Rules]
[Pages 33914-34048]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-08533]

[[Page 33913]]

Vol. 85

Tuesday,

No. 106

June 2, 2020

Part III

Department of Commerce

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National Oceanic and Atmospheric Administration

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50 CFR Part 218

Taking and Importing Marine Mammals; Taking Marine Mammals Incidental
to the U.S. Navy Training and Testing Activities in the Northwest
Training and Testing (NWTT) Study Area; Proposed Rule

Federal Register / Vol. 85, No. 106 / Tuesday, June 2, 2020 /
Proposed Rules

[[Page 33914]]

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 218

[200417-0114]
RIN 0648-BJ30

Taking and Importing Marine Mammals; Taking Marine Mammals
Incidental to the U.S. Navy Training and Testing Activities in the
Northwest Training and Testing (NWTT) Study Area

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.

ACTION: Proposed rule; request for comments and information.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) to take
marine mammals incidental to training and testing activities conducted
in the Northwest Training and Testing (NWTT) Study Area. Pursuant to
the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on
its proposal to issue regulations and subsequent Letters of
Authorization (LOAs) to the Navy to incidentally take marine mammals
during the specified activities. NMFS will consider public comments
prior to issuing any final rule and making final decisions on the
issuance of the requested LOAs. Agency responses to public comments
will be provided in the notice of the final decision. The Navy's
activities qualify as military readiness activities pursuant to the
MMPA, as amended by the National Defense Authorization Act for Fiscal
Year 2004 (2004 NDAA).

DATES: Comments and information must be received no later than July 17,
2020.

ADDRESSES: You may submit comments on this document, identified by
NOAA-NMFS-2020-0055, by any of the following methods:
Electronic submission: Submit all electronic public
comments via the Federal e-Rulemaking Portal. Go to
www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2020-0055, click the
``Comment Now!'' icon, complete the required fields, and enter or
attach your comments.
Mail: Submit written comments to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service, 1315 East-West Highway, Silver
Spring, MD 20910.
Instructions: Comments sent by any other method, to any other
address or individual, or received after the end of the comment period,
may not be considered by NMFS. All comments received are a part of the
public record and will generally be posted for public viewing on
www.regulations.gov without change. All personal identifying
information (e.g., name, address), confidential business information,
or otherwise sensitive information submitted voluntarily by the sender
will be publicly accessible. NMFS will accept anonymous comments (enter
``N/A'' in the required fields if you wish to remain anonymous).
Attachments to electronic comments will be accepted in Microsoft Word,
Excel, or Adobe PDF file formats only.
A copy of the Navy's application and other supporting documents and
documents cited herein may be obtained online at:
www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities. In case of problems
accessing these documents, please use the contact listed here (see FOR
FURTHER INFORMATION CONTACT).

FOR FURTHER INFORMATION CONTACT: Wendy Piniak, Office of Protected
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Purpose of Regulatory Action

These proposed regulations, issued under the authority of the MMPA
(16 U.S.C. 1361 et seq.), would provide the framework for authorizing
the take of marine mammals incidental to the Navy's training and
testing activities (which qualify as military readiness activities)
from the use of sonar and other transducers, in-water detonations, and
potential vessel strikes based on Navy movement in the NWTT Study Area.
The Study Area includes air and water space off the coast of
Washington, Oregon, and northern California; in the Western Behm Canal,
Alaska; and portions of waters of the Strait of Juan de Fuca and Puget
Sound, including Navy pierside and harbor locations in Puget Sound (see
Figure 1-1 of the Navy's rulemaking/LOA application).
NMFS received an application from the Navy requesting seven-year
regulations and authorizations to incidentally take individuals of
multiple species of marine mammals (``Navy's rulemaking/LOA
application'' or ``Navy's application''). Take is anticipated to occur
by Level A harassment and Level B harassment as well as a very small
number of serious injuries or mortalities incidental to the Navy's
training and testing activities.

Background

The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA direct the
Secretary of Commerce (as delegated to NMFS) to allow, upon request,
the incidental, but not intentional, taking of small numbers of marine
mammals by U.S. citizens who engage in a specified activity (other than
commercial fishing) within a specified geographical region if certain
findings are made and either regulations are issued or, if the taking
is limited to harassment, the public is provided with notice of the
proposed incidental take authorization and provided the opportunity to
review and submit comments.
An authorization for incidental takings shall be granted if NMFS
finds that the taking will have a negligible impact on the species or
stocks and will not have an unmitigable adverse impact on the
availability of the species or stocks for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other means of effecting the least practicable adverse
impact on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of such species or stocks for
taking for certain subsistence uses (referred to in this rule as
``mitigation measures''); and requirements pertaining to the monitoring
and reporting of such takings. The MMPA defines ``take'' to mean to
harass, hunt, capture, or kill, or attempt to harass, hunt, capture, or
kill any marine mammal. The Preliminary Analysis and Negligible Impact
Determination section below discusses the definition of ``negligible
impact.''
The NDAA for Fiscal Year 2004 (2004 NDAA) (Pub. L. 108-136) amended
section 101(a)(5) of the MMPA to remove the ``small numbers'' and
``specified geographical region'' provisions indicated above and
amended the definition of ``harassment'' as applied to a ``military
readiness activity.'' The definition of harassment for military
readiness activities (Section 3(18)(B) of the MMPA) is (i) Any act that
injures or has the significant potential to injure a marine mammal or
marine mammal stock in the wild (Level A Harassment); or (ii) Any act
that disturbs or is likely to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of natural behavioral patterns,
including, but not limited to, migration, surfacing, nursing, breeding,
feeding, or sheltering, to a

[[Page 33915]]

point where such behavioral patterns are abandoned or significantly
altered (Level B harassment). In addition, the 2004 NDAA amended the
MMPA as it relates to military readiness activities such that the least
practicable adverse impact analysis shall include consideration of
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
More recently, Section 316 of the NDAA for Fiscal Year 2019 (2019
NDAA) (Pub. L. 115-232), signed on August 13, 2018, amended the MMPA to
allow incidental take rules for military readiness activities under
section 101(a)(5)(A) to be issued for up to seven years. Prior to this
amendment, all incidental take rules under section 101(a)(5)(A) were
limited to five years.

Summary and Background of Request

On March 11, 2019, NMFS received an application from the Navy for
authorization to take marine mammals by Level A harassment and Level B
harassment incidental to training and testing activities (which qualify
as military readiness activities) from the use of sonar and other
transducers and in-water detonations in the NWTT Study Area over a
seven-year period beginning when the current authorization expires. In
addition, the Navy requested incidental take authorization by serious
injury or mortality for up to three takes of large whales from vessel
strikes over the seven-year period. We received revised applications on
June 6, 2019 and June 21, 2019 which provided revisions in the take
number estimates and vessel strike analysis and Navy's rulemaking/LOA
application was found to be adequate and complete. On August 6, 2019
(84 FR 38225), we published a notice of receipt (NOR) of application in
the Federal Register, requesting comments and information related to
the Navy's request for 30 days. We reviewed and considered all comments
and information received on the NOR in development of this proposed
rule. On October 4, 2019, the Navy submitted an amendment to its
application which incorporated new Southern Resident killer whale
offshore density information, and on December 19, 2019, the Navy
submitted an amendment to its application which incorporated revised
testing activity numbers.
The following types of training and testing, which are classified
as military readiness activities pursuant to the MMPA, as amended by
the 2004 NDAA, would be covered under the regulations and LOAs (if
authorized): Anti-submarine warfare (sonar and other transducers,
underwater detonations), mine warfare (sonar and other transducers,
underwater detonations), surface warfare (underwater detonations), and
other testing and training (sonar and other transducers). The
activities would not include pile driving/removal or use of air guns.
This would be the third time NMFS has promulgated incidental take
regulations pursuant to the MMPA relating to similar military readiness
activities in the NWTT Study Area, following those effective from
November 9, 2010 through November 8, 2015 (75 FR 69275; November 10,
2010) and from November 9, 2015 through November 8, 2020 (80 FR 73555;
November 24, 2015).
The Navy's mission is to organize, train, equip, and maintain
combat-ready naval forces capable of winning wars, deterring
aggression, and maintaining freedom of the seas. This mission is
mandated by Federal law (10 U.S.C. 8062), which requires the readiness
of the naval forces of the United States. The Navy executes this
responsibility in part by training and testing at sea, often in
designated operating areas (OPAREA) and testing and training ranges.
The Navy must be able to access and utilize these areas and associated
sea space and air space in order to develop and maintain skills for
conducting naval operations. The Navy's testing activities ensure naval
forces are equipped with well-maintained systems that take advantage of
the latest technological advances. The Navy's research and acquisition
community conducts military readiness activities that involve testing.
The Navy tests ships, aircraft, weapons, combat systems, sensors, and
related equipment, and conducts scientific research activities to
achieve and maintain military readiness.
The Navy has been conducting training and testing activities in the
NWTT Study Area for decades, with some activities dating back to at
least the early 1900s. The tempo and types of training and testing
activities have fluctuated because of the introduction of new
technologies, the evolving nature of international events, advances in
warfighting doctrine and procedures, and changes in force structure
(e.g., organization of ships, submarines, aircraft, weapons, and
personnel). Such developments influence the frequency, duration,
intensity, and location of required training and testing activities,
however the Navy's proposed activities for the period of this proposed
rule would be largely a continuation of ongoing activities. In addition
to ongoing activities, the Navy is proposing some new training
activities such as torpedo exercise--submarine training and unmanned
underwater vehicle training.\1\ The Navy is also proposing some new
testing activities, including: At-sea sonar testing, mine
countermeasure and neutralization testing, mine detection and
classification testing, kinetic energy weapon testing, propulsion
testing, undersea warfare testing, vessel signature evaluation,
acoustic and oceanographic research, radar and other system testing,
and simulant testing.\2\
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\1\ Some of the activities included here are new to the 2019
NWTT DSEIS/OEIS, but are not new to the Study Area. TORPEX--SUB
activity was previously analyzed in 2010 as part of the Sinking
Exercise. The Sinking Exercise is no longer conducted in the NWTT
Study Area and the TORPEX--SUB activity is now a separate activity
included in the NWTT DSEIS/OEIS. Unmanned underwater vehicle
activity was analyzed in 2010 as a testing activity, but is now
being included as a training activity.
\2\ Mine detection and classification testing was analyzed in
2010 in the Inland waters, but was not previously analyzed in the
Offshore waters. Vessel signature evaluation testing was analyzed in
2010 as a component to other activities, but is included in the list
of new activities because it was not previously identified as an
independent activity.
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The Navy's rulemaking/LOA application reflects the most up-to-date
compilation of training and testing activities deemed necessary by
senior Navy leadership to accomplish military readiness requirements.
The types and numbers of activities included in the proposed rule
account for fluctuations in training and testing in order to meet
evolving or emergent military readiness requirements. These proposed
regulations would cover training and testing activities that would
occur for a seven-year period following the expiration of the current
MMPA authorization for the NWTT Study Area, which expires on November
8, 2020.

Description of the Specified Activity

The Navy requests authorization to take marine mammals incidental
to conducting training and testing activities. The Navy has determined
that acoustic and explosives stressors are most likely to result in
impacts on marine mammals that could rise to the level of harassment,
and NMFS concurs with this determination. Detailed descriptions of
these activities are provided in Chapter 2 of the 2019 NWTT Draft
Supplemental Environmental Impact Statement (SEIS)/Overseas EIS (OEIS)
(2019 NWTT DSEIS/OEIS) (https://www.nwtteis.com) and in the Navy's
rulemaking/LOA application (https://www.fisheries.noaa.gov/national/
marine-mammal-protection/incidental-take-authorizations-military-
readiness-activities) and are summarized here.

[[Page 33916]]

Dates and Duration

The specified activities would occur at any time during the seven-
year period of validity of the regulations. The proposed number of
training and testing activities are described in the Detailed
Description of the Specified Activities section (Tables 3 through 4).

Geographical Region

The NWTT Study Area is composed of established maritime operating
and warning areas in the eastern North Pacific Ocean region, including
areas of the Strait of Juan de Fuca, Puget Sound, and Western Behm
Canal in southeastern Alaska. The Study Area includes air and water
space within and outside Washington state waters, within Alaska state
waters, and outside state waters of Oregon and Northern California
(Figure 1). The eastern boundary of the Offshore Area portion of the
Study Area is 12 nautical miles (nmi) off the coastline for most of the
Study Area, including southern Washington, Oregon, and Northern
California. The Offshore Area includes the ocean all the way to the
coastline only along that part of the Washington coast that lies
beneath the airspace of W-237 and the Olympic Military Operating Area
(MOA) and the Washington coastline north of the Olympic MOA. The Study
Area includes four existing range complexes and facilities: The
Northwest Training Range Complex, the Keyport Range Complex, Carr Inlet
Operations Area, and the Southeast Alaska Acoustic Measurement Facility
(Western Behm Canal, Alaska). In addition to these range complexes, the
Study Area also includes Navy pierside locations where sonar
maintenance and testing occurs as part of overhaul, modernization,
maintenance, and repair activities at Naval Base Kitsap, Bremerton;
Naval Base Kitsap, Bangor; and Naval Station Everett. Additional detail
can be found in Chapter 2 of the Navy's rulemaking/LOA application.
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Primary Mission Areas

The Navy categorizes many of its training and testing activities
into functional warfare areas called primary mission areas. The Navy's
proposed activities for NWTT generally fall into the following six
primary mission areas: Air warfare; anti-submarine warfare; electronic
warfare; expeditionary warfare; mine warfare; and surface warfare. Most
activities conducted in NWTT are categorized under one of these primary
mission areas; activities that do not fall within one of these areas
are listed as ``other activities.'' Each warfare community (surface,
subsurface, aviation, and expeditionary warfare) may train in some or
all of these primary mission areas. The research and acquisition
community also categorizes most, but not all, of its testing activities
under these primary mission areas. A description of the sonar,
munitions, targets, systems, and other material used during training
and testing activities within these primary mission areas is provided
in Appendix A (Navy Activities Descriptions) of the 2019 NWTT DSEIS/
OEIS.
The Navy describes and analyzes the effects of its activities
within the 2019 NWTT DSEIS/OEIS. In its assessment, the Navy concluded
that sonar and other transducers and underwater detonations were the
stressors most likely to result in impacts on marine mammals that could
rise to the level of harassment as defined under the MMPA. Therefore,
the Navy's rulemaking/LOA application provides the Navy's assessment of
potential effects from these stressors in terms of the various warfare
mission areas in which they would be conducted. Those mission areas
include the following:
Anti-submarine warfare (sonar and other transducers,
underwater detonations);
expeditionary warfare;
mine warfare (sonar and other transducers, underwater
detonations);
surface warfare (underwater detonations); and
other (sonar and other transducers).
The Navy's training and testing activities in air warfare and
electronic warfare do not involve sonar and other transducers,
underwater detonations, or any other stressors that could result in
harassment, serious injury, or mortality of marine mammals. Therefore,
the activities in air warfare and electronic warfare are not discussed
further in this proposed rule, but are analyzed fully in the 2019 NWTT
DSEIS/OEIS.
Anti-Submarine Warfare
The mission of anti-submarine warfare is to locate, neutralize, and
defeat hostile submarine forces that threaten Navy surface forces.
Anti-submarine warfare can involve various assets such as aircraft,
ships, and submarines which all search for hostile submarines. These
forces operate together or independently to gain early warning and
detection, and to localize, track, target, and attack submarine
threats.
Anti-submarine warfare training addresses basic skills such as
detecting and classifying submarines, as well as evaluating sounds to
distinguish between enemy submarines and friendly submarines, ships,
and marine life. More advanced training integrates the full spectrum of
anti-submarine warfare, from detecting and tracking a submarine to
attacking a target using either exercise torpedoes (i.e., torpedoes
that do not contain a warhead), or simulated weapons. These integrated
anti-submarine warfare training exercises are conducted in coordinated,
at-sea training events involving submarines, ships, and aircraft.
Testing of anti-submarine warfare systems is conducted to develop
new technologies and assess weapon performance and operability with new
systems and platforms, such as unmanned systems. Testing uses ships,
submarines, and aircraft to demonstrate capabilities of torpedoes
(exercise and explosive), missiles, countermeasure systems, and
underwater surveillance and communications systems. Tests may be
conducted as part of a large-scale training event involving submarines,
ships, fixed-wing aircraft, and helicopters. These integrated training
events offer opportunities to conduct research and acquisition
activities and to train aircrew in the use of new or newly enhanced
systems during a large-scale, complex exercise.
Expeditionary Warfare
The mission of expeditionary warfare is to provide security and
surveillance in the littoral (at the shoreline), riparian (along a
river), or coastal environments. Expeditionary warfare is wide ranging
and includes defense of harbors, operation of remotely operated
vehicles, defense against swimmers, and boarding/seizure operations.
Expeditionary warfare training activities include underwater
construction team training, dive and salvage operations, and insertion/
extraction via air, surface, and subsurface platforms.
Mine Warfare
The mission of mine warfare is to detect, classify, and avoid or
neutralize (disable) mines to protect Navy ships and submarines and to
maintain free access to ports and shipping lanes. Mine warfare also
includes training and testing in offensive mine laying to gain control
of or deny the enemy access to sea space. Naval mines can be laid by
ships, submarines, or aircraft.
Mine warfare training includes exercises in which ships, aircraft,
submarines, underwater vehicles, unmanned vehicles, or marine mammal
detection systems search for mine shapes. Personnel train to destroy or
disable mines by attaching underwater explosives to or near the mine or
using remotely operated vehicles to destroy the mine. Towed influence
mine sweep systems mimic a particular ship's magnetic and acoustic
signature, which would trigger a real mine, causing it to explode.
Testing and development of mine warfare systems is conducted to
improve acoustic, optical, and magnetic detectors intended to hunt,
locate, and record the positions of mines for avoidance or subsequent
neutralization. Mine warfare testing and development falls into two
primary categories: Mine detection and classification, and mine
countermeasure and neutralization testing. Mine detection and
classification testing involves the use of air, surface, and subsurface
vessels; it uses sonar, including towed and side-scan sonar, and
unmanned vehicles to locate and identify objects underwater. Mine
detection and classification systems are sometimes used in conjunction
with a mine neutralization system. Mine countermeasure and
neutralization testing includes the use of air, surface, and subsurface
units and uses tracking devices, countermeasure and neutralization
systems, and general purpose bombs to evaluate the effectiveness of
neutralizing mine threats. Most neutralization tests use mine shapes,
or non-explosive practice mines, to accomplish the requirements of the
activity. For example, during a mine neutralization test, a previously
located mine is destroyed or rendered nonfunctional using a helicopter
or manned/unmanned surface vehicle-based system that may involve the
deployment of a towed neutralization system.
A small percentage of mine warfare activities require the use of
high-explosives to evaluate and confirm the ability of the system or
the crews conducting the training to neutralize a high-explosive mine
under operational conditions. The majority of mine warfare systems are
deployed by ships, helicopters, and unmanned vehicles. Tests may also
be conducted in support of scientific research to support these new
technologies.

[[Page 33919]]

Surface Warfare
The mission of surface warfare is to obtain control of sea space
from which naval forces may operate, which entails offensive action
against surface targets while also defending against aggressive actions
by enemy forces. In the conduct of surface warfare, aircraft use guns,
air-launched cruise missiles, or other precision-guided munitions;
ships employ naval guns and surface-to-surface missiles; and submarines
attack surface ships using torpedoes or submarine-launched, anti-ship
cruise missiles.
Surface warfare training includes surface-to-surface gunnery and
missile exercises, air-to-surface gunnery and missile exercises,
submarine missile or torpedo launch events, and other munitions against
surface targets.
Testing of weapons used in surface warfare is conducted to develop
new technologies and to assess weapon performance and operability with
new systems and platforms, such as unmanned systems. Tests include
various air-to-surface guns and missiles, surface-to-surface guns and
missiles, and bombing tests. Testing events may be integrated into
training activities to test aircraft or aircraft systems in the
delivery of munitions on a surface target. In most cases the tested
systems are used in the same manner in which they are used for training
activities.
Other Activities
The Navy conducts other training and testing activities in the
Study Area that fall outside of the primary mission areas, but support
overall readiness. Surface ship crews conduct Maritime Security
Operations events, including maritime security escorts for Navy vessels
such as Fleet Ballistic Missile Submarines; Visit, Board, Search, and
Seizure; Maritime Interdiction Operations; Force Protection; Anti-
Piracy Operations, Acoustic Component Testing, Cold Water Support, and
Hydrodynamic and Maneuverability testing. Anti-terrorism/Force-
protection training will occur as small boat attacks against moored
ships at one of the Navy's piers inside Puget Sound. Pierside and at-
sea maintenance of ship and submarine sonar is required for systems
upkeep and systems evaluation.

Description of Stressors

The Navy uses a variety of sensors, platforms, weapons, and other
devices, including ones used to ensure the safety of Sailors, to meet
its mission. Training and testing with these systems may introduce
acoustic (sound) energy or shock waves from explosives into the
environment. The proposed training and testing activities were
evaluated to identify specific components that could act as stressors
by having direct or indirect impacts on the environment. This analysis
included identification of the spatial variation of the identified
stressors. The following subsections describe the acoustic and
explosive stressors for marine mammals and their habitat (including
prey species) within the NWTT Study Area. Each description contains a
list of activities that may generate the stressor. Stressor/resource
interactions that were determined to have de minimis or no impacts
(e.g., vessel noise, aircraft noise, weapons noise, and explosions in
air) were not carried forward for analysis in the Navy's rulemaking/LOA
application. No Major Training Exercises (MTEs) or Sinking Exercise
(SINKEX) events are proposed in the NWTT Study Area. NMFS reviewed the
Navy's analysis and conclusions on de minimis sources and finds them
complete and supportable.

Acoustic Stressors

Acoustic stressors include acoustic signals emitted into the water
for a specific purpose, such as sonar, other transducers (devices that
convert energy from one form to another--in this case, into sound
waves), incidental sources of broadband sound produced as a byproduct
of vessel movement, aircraft transits, and use of weapons or other
deployed objects. Explosives also produce broadband sound but are
characterized separately from other acoustic sources due to their
unique hazardous characteristics. Characteristics of each of these
sound sources are described in the following sections.
In order to better organize and facilitate the analysis of
approximately 300 sources of underwater sound used in training and
testing activities by the Navy, including sonar and other transducers
and explosives, a series of source classifications, or source bins,
were developed. The source classification bins do not include the
broadband noise produced incidental to vessel and aircraft transits and
weapons firing. Noise produced from vessel, aircraft, and weapons
firing activities are not carried forward because those activities were
found to have de minimis or no impacts, as stated above.
The use of source classification bins provides the following
benefits:
Provides the ability for new sensors or munitions to be
covered under existing authorizations, as long as those sources fall
within the parameters of a ``bin;''
Improves efficiency of source utilization data collection
and reporting requirements anticipated under the MMPA authorizations;
Ensures a precautionary approach to all impact estimates,
as all sources within a given class are modeled as the most impactful
source (highest source level, longest duty cycle, or largest net
explosive weight) within that bin;
Allows analyses to be conducted in a more efficient
manner, without any compromise of analytical results; and
Provides a framework to support the reallocation of source
usage (hours/explosives) between different source bins, as long as the
total numbers of takes remain within the overall analyzed and
authorized limits. This flexibility is required to support evolving
Navy training and testing requirements, which are linked to real world
events.
Sonar and Other Transducers
Active sonar and other transducers emit non-impulsive sound waves
into the water to detect objects, navigate safely, and communicate.
Passive sonars differ from active sound sources in that they do not
emit acoustic signals; rather, they only receive acoustic information
about the environment, or listen. In this proposed rule, the terms
sonar and other transducers will be used to indicate active sound
sources unless otherwise specified.
The Navy employs a variety of sonars and other transducers to
obtain and transmit information about the undersea environment. Some
examples are mid-frequency hull-mounted sonars used to find and track
enemy submarines; high-frequency small object detection sonars used to
detect mines; high-frequency underwater modems used to transfer data
over short ranges; and extremely high-frequency (greater than 200
kilohertz (kHz)) doppler sonars used for navigation, like those used on
commercial and private vessels. The characteristics of these sonars and
other transducers, such as source level, beam width, directivity, and
frequency, depend on the purpose of the source. Higher frequencies can
carry more information or provide more information about objects off
which they reflect, but attenuate more rapidly. Lower frequencies
attenuate less rapidly, so they may detect objects over a longer
distance, but with less detail.
Propagation of sound produced underwater is highly dependent on
environmental characteristics such as bathymetry, bottom type, water
depth, temperature, and salinity. The sound received at a particular
location will be different than near the source due to the

[[Page 33920]]

interaction of many factors, including propagation loss; how the sound
is reflected, refracted, or scattered; the potential for reverberation;
and interference due to multi-path propagation. In addition, absorption
greatly affects the distance over which higher-frequency sounds
propagate. The effects of these factors are explained in Appendix D
(Acoustic and Explosive Concepts) of the 2019 NWTT DSEIS/OEIS. Because
of the complexity of analyzing sound propagation in the ocean
environment, the Navy relies on acoustic models in its environmental
analyses that consider sound source characteristics and varying ocean
conditions across the Study Area.
The sound sources and platforms typically used in naval activities
analyzed in the Navy's rulemaking/LOA application are described in
Appendix A (Navy Activities Descriptions) of the 2019 NWTT DSEIS/OEIS.
Sonars and other transducers used to obtain and transmit information
underwater during Navy training and testing activities generally fall
into several categories of use described below.

Anti-Submarine Warfare

Sonar used during anti-submarine warfare training and testing would
impart the greatest amount of acoustic energy of any category of sonar
and other transducers analyzed in this proposed rule. Types of sonars
used to detect potential enemy vessels include hull-mounted, towed,
line array, sonobuoy, helicopter dipping, and torpedo sonars. In
addition, acoustic targets and decoys (countermeasures) may be deployed
to emulate the sound signatures of vessels or repeat received signals.
Most anti-submarine warfare sonars are mid-frequency (1-10 kHz)
because mid-frequency sound balances sufficient resolution to identify
targets with distance over which threats can be identified. However,
some sources may use higher or lower frequencies. Duty cycles can vary
widely, from rarely used to continuously active. Anti-submarine warfare
sonars can be wide-ranging in a search mode or highly directional in a
track mode.
Most anti-submarine warfare activities involving submarines or
submarine targets would occur in waters greater than 600 feet (ft) deep
due to safety concerns about running aground at shallower depths.
Sonars used for anti-submarine warfare activities would typically be
used beyond 12 nmi from shore. Exceptions include use of dipping sonar
by helicopters, pierside testing and maintenance of systems while in
port, and system checks while transiting to or from port.

Mine Warfare, Small Object Detection, and Imaging

Sonars used to locate mines and other small objects, as well as
those used in imaging (e.g., for hull inspections or imaging of the
seafloor), are typically high frequency or very high frequency. Higher
frequencies allow for greater resolution and, due to their greater
attenuation, are most effective over shorter distances. Mine detection
sonar can be deployed (towed or vessel hull-mounted) at variable depths
on moving platforms (ships, helicopters, or unmanned vehicles) to sweep
a suspected mined area. Hull-mounted anti-submarine sonars can also be
used in an object detection mode known as ``Kingfisher'' mode. Sonars
used for imaging are usually used in close proximity to the area of
interest, such as pointing downward near the seafloor.
Mine detection sonar use would be concentrated in areas where
practice mines are deployed, typically in water depths less than 200
ft, and at temporary minefields close to strategic ports and harbors,
or at targets of opportunity such as navigation buoys. Kingfisher mode
on vessels is most likely to be used when transiting to and from port.
Sound sources used for imaging could be used throughout the NWTT Study
Area.

Navigation and Safety

Similar to commercial and private vessels, Navy vessels employ
navigational acoustic devices, including speed logs, Doppler sonars for
ship positioning, and fathometers. These may be in use at any time for
safe vessel operation. These sources are typically highly directional
to obtain specific navigational data.

Communication

Sound sources used to transmit data (such as underwater modems),
provide location (pingers), or send a single brief release signal to
bottom-mounted devices (acoustic release) may be used throughout the
NWTT Study Area. These sources typically have low duty cycles and are
usually only used when it is desirable to send a detectable acoustic
message.

Classification of Sonar and Other Transducers

Sonars and other transducers are grouped into classes that share an
attribute, such as frequency range or purpose. As detailed below,
classes are further sorted by bins based on the frequency or bandwidth;
source level; and, when warranted, the application in which the source
would be used. Unless stated otherwise, a reference distance of 1 meter
(m) is used for sonar and other transducers.
Frequency of the non-impulsive acoustic source:
[cir] Low-frequency sources operate below 1 kHz;
[cir] Mid-frequency sources operate at and above 1 kHz, up to and
including 10 kHz;
[cir] High-frequency sources operate above 10 kHz, up to and
including 100 kHz; and
[cir] Very-high-frequency sources operate above 100 kHz but below
200 kHz.
Sound pressure level:
[cir] Greater than 160 decibels (dB) referenced to 1 micropascal
(re: 1 [mu]Pa), but less than 180 dB re: 1 [mu]Pa;
[cir] Equal to 180 dB re: 1 [mu]Pa and up to 200 dB re: 1 [mu]Pa;
and
[cir] Greater than 200 dB re: 1 [mu]Pa.
Application in which the source would be used:
[cir] Sources with similar functions that have similar
characteristics, such as pulse length (duration of each pulse), beam
pattern, and duty cycle.
The bins used for classifying active sonars and transducers that
are quantitatively analyzed in the Study Area are shown in Table 1.
While general parameters or source characteristics are shown in the
table, actual source parameters are classified.

Table 1--Sonar and Other Transducers Quantitatively Analyzed in the NWTT
Study Area
------------------------------------------------------------------------
Source class category Bin Description
------------------------------------------------------------------------
Low-Frequency (LF): Sources that LF4 LF sources equal to 180
produce signals less than 1 kHz. LF5 dB and up to 200 dB.
LF sources less than
180 dB.
Mid-Frequency (MF): Tactical and MF1 Hull-mounted surface
non-tactical sources that ............. ship sonars (e.g., AN/
produce signals between 1 and MF1K SQS-53C and AN/SQS-
10 kHz. 60).
Kingfisher mode
associated with MF1
sonars.

[[Page 33921]]

MF2 Hull-mounted surface
ship sonars (e.g., AN/
SQS-56).
MF3 Hull-mounted submarine
sonars (e.g., AN/BQQ-
10).
MF4 Helicopter-deployed
dipping sonars (e.g.,
AN/AQS-22).
MF5 Active acoustic
sonobuoys (e.g.,
DICASS).
MF6 Underwater sound signal
devices (e.g., MK 84
SUS).
MF9 Sources (equal to 180
dB and up to 200 dB)
not otherwise binned.
MF10 Active sources (greater
than 160 dB, but less
than 180 dB) not
otherwise binned.
MF11 Hull-mounted surface
ship sonars with an
active duty cycle
greater than 80%.
MF12 Towed array surface
ship sonars with an
active duty cycle
greater than 80%.
High-Frequency (HF): Tactical HF1 Hull-mounted submarine
and non-tactical sources that HF3 sonars (e.g., AN/BQQ-
produce signals between 10 and 10).
100 kHz. Other hull-mounted
submarine sonars
(classified).
HF4 Mine detection,
classification, and
neutralization sonar
(e.g., AN/SQS-20).
HF5 Active sources (greater
than 200 dB) not
otherwise binned.
HF6 Sources (equal to 180
dB and up to 200 dB)
not otherwise binned.
HF8 Hull-mounted surface
ship sonars (e.g., AN/
SQS-61).
HF9 Weapon-emulating sonar
source.
Very High-Frequency (VHF): VHF1 Active sources greater
Tactical and non-tactical VHF2 than 200 dB.
sources that produce signals Active sources with a
greater than 100 kHz but less source level less than
than 200 kHz. 200 dB.
Anti-Submarine Warfare (ASW): ASW1 MF systems operating
Tactical sources (e.g., active ASW2 above 200 dB.
sonobuoys and acoustic ASW3 MF Multistatic Active
countermeasures systems) used Coherent sonobuoy
during ASW training and testing (e.g., AN/SSQ-125).
activities. MF towed active
acoustic
countermeasure systems
(e.g., AN/SLQ-25).
ASW4 MF expendable active
acoustic device
countermeasures (e.g.,
MK 3).
ASW5 \1\ MF sonobuoys with high
duty cycles.
Torpedoes (TORP): Active TORP1 Lightweight torpedo
acoustic signals produced by ............. (e.g., MK 46, MK 54,
torpedoes. TORP2 or Anti-Torpedo
Torpedo).
Heavyweight torpedo
(e.g., MK 48).
TORP3 Heavyweight torpedo
(e.g., MK 48).
Looking Sonar (FLS): Forward or FLS2 HF sources with short
upward looking object avoidance pulse lengths, narrow
sonars used for ship navigation beam widths, and
and safety. focused beam patterns.
Acoustic Modems (M): Sources M3 MF acoustic modems
used to transmit data. (greater than 190 dB).
Synthetic Aperture Sonars (SAS): SAS2 HF SAS systems.
Sonars used to form high-
resolution images of the
seafloor.
Broadband Sound Sources (BB): BB1 MF to HF mine
Sonar systems with large BB2 countermeasure sonar.
frequency spectra, used for HF to VHF mine
various purposes. countermeasure sonar.
------------------------------------------------------------------------
\1\ Formerly ASW2 in the 2015-2020 (Phase II) rulemaking.

Explosive Stressors

The near-instantaneous rise from ambient to an extremely high peak
pressure is what makes an explosive shock wave potentially damaging.
Farther from an explosive, the peak pressures decay and the explosive
waves propagate as an impulsive, broadband sound. Several parameters
influence the effect of an explosive: The weight of the explosive in
the warhead, the type of explosive material, the boundaries and
characteristics of the propagation medium, and the detonation depth in
water. The net explosive weight, which is the explosive power of a
charge expressed as the equivalent weight of trinitrotoluene (TNT),
accounts for the first two parameters. The effects of these factors are
explained in Appendix D (Acoustic and Explosive Concepts) of the 2019
NWTT DSEIS/OEIS. The activities analyzed in the Navy's rulemaking/LOA
application that use explosives are described in Appendix A (Navy
Activities Descriptions) of the 2019 NWTT DSEIS/OEIS. Explanations of
the terminology and metrics used when describing explosives are
provided in Appendix D (Acoustic and Explosive Concepts) of the 2019
NWTT DSEIS/OEIS.
Explosives in Water
Explosive detonations during training and testing activities are
associated with high-explosive munitions, including, but not limited
to, bombs, missiles, naval gun shells, torpedoes, mines, demolition
charges, and explosive sonobuoys. Explosive detonations during training
and testing involving the use of high-explosive munitions, including
bombs, missiles, and naval gun shells, could occur in the air or near
the water's surface. Explosive detonations associated with torpedoes
and explosive sonobuoys would occur in the water column; mines and
demolition charges could be detonated in the water column or on the
ocean bottom. Detonations would typically occur in waters greater than
200 ft in depth, and greater than 50 nmi from shore, with the exception
of mine countermeasure and neutralization testing proposed in the
Offshore Area, and existing mine warfare areas in Inland Waters (i.e.,
Crescent Harbor and Hood Canal Explosive Ordnance Disposal Training
Ranges). Mine countermeasure and neutralization testing is a new
proposed testing activity that would occur closer to shore than other
in-water explosive activities

[[Page 33922]]

analyzed in the 2015 NWTT Final EIS/OEIS for the Offshore Area of the
NWTT Study Area. This activity would occur in waters 3 nmi or greater
from shore in the Quinault Range Site (outside the Olympic Coast
National Marine Sanctuary), or 12 nmi or greater from shore elsewhere
in the Offshore Area. Two of the three events would involve the use of
explosives, and would typically occur in water depths shallower than
1,000 ft. The two multi-day events (1-10 days per event) would include
up to 36 E4 explosives (>2.5-5 lb net explosive weight) and 5 E7
explosives (>20-60 lb net explosive weight). In order to better
organize and facilitate the analysis of explosives used by the Navy
during training and testing that could detonate in water or at the
water surface, explosive classification bins were developed. The use of
explosive classification bins provides the same benefits discussed
above and as described for acoustic source classification bins in
Section 1.4.1 (Acoustic Stressors) of the Navy's rulemaking/LOA
application.
Explosives detonated in water are binned by net explosive weight.
The bins of explosives that are proposed for use in the Study Area are
shown in Table 2 below.

Table 2--Explosive Sources Quantitatively Analyzed That Could Be Used Underwater or at the Water Surface in the
Study Area
----------------------------------------------------------------------------------------------------------------
Net explosive weight Example explosive
Bin (lb) source Modeled detonation depths (ft)
----------------------------------------------------------------------------------------------------------------
E1.............................. 0.1-0.25 Medium-caliber 0.3, 60.
projectiles.
E2.............................. >0.25-0.5 Medium-caliber 0.3.
projectiles.
E3.............................. >0.5-2.5 Explosive Ordnance 33, 60.
Disposal Mine
Neutralization.
E4.............................. >2.5-5 Mine 197, 262, 295, 394.
Countermeasure
and
Neutralization.
E5.............................. >5-10 Large-caliber 0.3.
projectile.
E7.............................. >20-60 Mine 33, 98, 230, 295.
Countermeasure
and
Neutralization.
E8.............................. >60-100 Lightweight 150.
torpedo.
E10............................. >250-500 1,000 lb bomb..... 0.3.
E11............................. >500-650 Heavyweight 300, 656.
torpedo.
----------------------------------------------------------------------------------------------------------------
Notes: Net Explosive Weight refers to the equivalent amount of TNT, the actual weight of a munition may be
larger due to other components; in = inch(es), lb = pound(s), ft = feet.

Propagation of explosive pressure waves in water is highly
dependent on environmental characteristics such as bathymetry, bottom
type, water depth, temperature, and salinity, which affect how the
pressure waves are reflected, refracted, or scattered; the potential
for reverberation; and interference due to multi-path propagation. In
addition, absorption greatly affects the distance over which higher-
frequency components of explosive broadband noise can propagate.
Appendix D (Acoustic and Explosive Concepts) of the 2019 NWTT DSEIS/
OEIS explains the characteristics of explosive detonations and how the
above factors affect the propagation of explosive energy in the water.
Because of the complexity of analyzing sound propagation in the ocean
environment, the Navy relies on acoustic models in its environmental
analyses that consider sound source characteristics and varying ocean
conditions across the Study Area.
Explosive Fragments
Marine mammals could be exposed to fragments from underwater
explosions associated with the specified activities. When explosive
ordnance (e.g., bomb or missile) detonates, fragments of the weapon are
thrown at high-velocity from the detonation point, which can injure or
kill marine mammals if they are struck. These fragments may be of
variable size and are ejected at supersonic speed from the detonation.
The casing fragments will be ejected at velocities much greater than
debris from any target due to the proximity of the casing to the
explosive material. Risk of fragment injury reduces exponentially with
distance as the fragment density is reduced. Fragments underwater tend
to be larger than fragments produced by in-air explosions (Swisdak and
Montaro, 1992). Underwater, the friction of the water would quickly
slow these fragments to a point where they no longer pose a threat.
Opposingly, the blast wave from an explosive detonation moves
efficiently through the seawater. Because the ranges to mortality and
injury due to exposure to the blast wave are likely to far exceed the
zone where fragments could injure or kill an animal, the ranges for
assessing the likelihood of mortality and injury from a blast, which
are also used to inform mitigation zones, are assumed to encompass risk
due to fragmentation.

Other Stressor--Vessel Strike

NMFS also considered the chance that a vessel utilized in training
or testing activities could strike a marine mammal. Vessel strikes have
the potential to result in incidental take from serious injury and/or
mortality. Vessel strikes are not specific to any particular training
or testing activity, but rather are a limited, sporadic, and incidental
result of Navy vessel movement during training and testing activities
within a Study Area. Vessel strikes from commercial, recreational, and
military vessels are known to seriously injure and occasionally kill
cetaceans (Abramson et al., 2011; Berman-Kowalewski et al., 2010;
Calambokidis, 2012; Douglas et al., 2008; Laggner, 2009; Lammers et
al., 2003; Van der Hoop et al., 2012; Van der Hoop et al., 2013),
although reviews of the literature on ship strikes mainly involve
collisions between commercial vessels and whales (Jensen and Silber,
2003; Laist et al., 2001). Vessel speed, size, and mass are all
important factors in determining both the potential likelihood and
impacts of a vessel strike to marine mammals (Conn and Silber, 2013;
Gende et al., 2011; Silber et al., 2010; Vanderlaan and Taggart, 2007;
Wiley et al., 2016). For large vessels, speed and angle of approach can
influence the severity of a strike.
Navy vessels transit at speeds that are optimal for fuel
conservation and to meet training and testing requirements. Vessels
used as part of the proposed Specified Activities include ships,
submarines, unmanned vessels, and boats ranging in size from small, 22
ft (7 m) rigid hull inflatable boats to aircraft carriers with lengths
up to 1,092 ft (333 m). The average speed of large Navy ships ranges
between 10 and 15 knots (kn) and submarines generally operate at speeds
in the range of 8 to 13 kn, while a few specialized vessels can travel
at faster speeds. Small craft (for

[[Page 33923]]

purposes of this analysis, less than 60 ft (18 m) in length) have much
more variable speeds (0 to 50+ kn, dependent on the activity), but
generally range from 10 to 14 kn. From unpublished Navy data, average
median speed for large Navy ships in the other Navy ranges from 2011-
2015 varied from 5 to 10 kn with variations by ship class and location
(i.e., slower speeds close to the coast). Similar patterns would occur
in the NWTT Study Area. A full description of Navy vessels that are
used during training and testing activities can be found in Chapter 2
(Description of Proposed Action and Alternatives) of the 2019 NWTT
DSEIS/OEIS.
While these speeds are representative of most events, some vessels
need to temporarily operate outside of these parameters for certain
times or during certain activities. For example, to produce the
required relative wind speed over the flight deck, an aircraft carrier
engaged in flight operations must adjust its speed through the water
accordingly. Conversely, there are other instances, such as launch and
recovery of a small rigid hull inflatable boat; vessel boarding,
search, and seizure training events; or retrieval of a target when
vessels will be dead in the water or moving slowly ahead to maintain
steerage.
Large Navy vessels (greater than 60 ft (18 m) in length) within the
offshore areas of range complexes and testing ranges operate
differently from commercial vessels in ways that may reduce potential
whale collisions. Surface ships operated by or for the Navy have
multiple personnel assigned to stand watch at all times, when a ship or
surfaced submarine is moving through the water (underway). A primary
duty of personnel standing watch on surface ships is to detect and
report all objects and disturbances sighted in the water that may
indicate a threat to the vessel and its crew, such as debris, a
periscope, surfaced submarine, or surface disturbance. Per vessel
safety requirements, personnel standing watch also report any marine
mammals sighted in the path of the vessel as a standard collision
avoidance procedure. All vessels proceed at a safe speed so they can
take proper and effective action to avoid a collision with any sighted
object or disturbance, and can be stopped within a distance appropriate
to the prevailing circumstances and conditions.

Detailed Description of Proposed Activities

Proposed Training and Testing Activities

The training and testing activities that the Navy proposes to
conduct in the NWTT Study Area are summarized in Table 3 (training) and
Table 4 (testing). The tables are organized according to primary
mission areas and include the activity name, associated stressor(s) of
Navy's activities, description and duration of the activity, sound
source bin, the areas where the activities are conducted in the NWTT
Study Area, and the number of activities. Under the ``Annual # of
Events'' column, events show either a single number or a range of
numbers to indicate the maximum number of times that activity could
occur during any single year. The ``7-Year # of Events'' is the maximum
number of times an activity would occur over the 7-year period of
proposed regulations. For further information regarding the primary
platform used (e.g., ship or aircraft type) see Appendix A (Training
and Testing Activities Descriptions) of the 2019 NWTT DSEIS/OEIS.
The Navy's proposed activities reflect a representative year of
training and testing to account for the natural fluctuation of training
and testing cycles and deployment schedules that generally prevents the
maximum level of activities from occurring year after year in any 7-
year period. As shown in the tables of activities, the number of some
activities may vary from year to year, and the level of variability can
differ by activity. Still, the annual analysis assumes a ``maximum''
year. For the purposes of this request, the Navy assumes that some
unit-level training would be conducted using synthetic means (e.g.,
simulators). Additionally, the request assumes that some unit-level
active sonar training and some testing will be completed during other
scheduled activities.

Table 3--Proposed Training Activities Analyzed for the Seven-Year Period in the NWTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual 7-Year
Stressor category Activity Description Typical duration Source bin Location # of # of
events events
--------------------------------------------------------------------------------------------------------------------------------------------------------
Anti-Submarine Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic; Explosive... Torpedo Exercise-- Submarine crews search for, track, 8 hours.......... TORP2............ Offshore Area 0-2 5
Submarine and detect submarines. Event would >12 nmi from
(TORPEX--Sub). include one MK-48 torpedo used land.
during this event.
Acoustic.............. Tracking Helicopter crews search for, track, 2-4 hours........ MF4, MF5......... Offshore Area 0-2 5
Exercise--Helico and detect submarines. >12 nmi from
pter (TRACKEX-- land.
Helo).
Acoustic.............. Tracking Maritime patrol aircraft crews 2-8 hours........ ASW2, ASW5, MF5, Offshore Area 373 2,611
Exercise--Mariti search for, track, and detect TORP1. >12 nmi from
me Patrol submarines. land.
Aircraft
(TRACKEX--MPA).
Acoustic.............. Tracking Surface ship crews search for, 2-4 hours........ ASW3, MF1, MF11.. Offshore Area... 62 434
Exercise--Ship track, and detect submarines.
(TRACKEX--Ship).
Acoustic.............. Tracking Submarine crews search for, track, 8 hours.......... HF1, MF3......... Offshore Area... 75-100 595
Exercise--Submar and detect submarines.
ine (TRACKEX--
Sub).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mine Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic.............. Civilian Port Maritime security personnel train Multiple days.... HF4, SAS2........ Inland Waters... 0-1 5
Defense--Homelan to protect civilian ports and
d Security Anti- harbors against enemy efforts to
Terrorism/Force interfere with access to those
Protection ports.
Exercises.

[[Page 33924]]

Explosive............. Mine Personnel disable threat mines Up to 4 hours.... E3............... Crescent Harbor 12 84
Neutralization-- using explosive charges. EOD Training
Explosive Range, Hood
Ordnance Canal EOD
Disposal (EOD). Training Range.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Surface Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Explosive............. Bombing Exercise Fixed-wing aircrews deliver bombs 1 hour........... E10.............. Offshore Area (W- * 0-2 5
(Air-to-Surface) against surface targets. 237) >50 nmi
(BOMBEX [A-S]). from land.
Explosive............. Gunnery Exercise Surface ship crews fire large- and Up to 3 hours.... E1, E2, E5....... Offshore Area * 90 504
(Surface-to- medium-caliber guns at surface >50 nmi from
Surface)--Ship targets. land.
(GUNEX [S-S]--
Ship).
Explosive............. Missile Exercise Fixed-wing aircrews simulate firing 2 hours.......... E10.............. Offshore Area (W- 0-2 5
(Air-to-Surface) precision-guided missiles, using 237) >50 nmi
(MISSILEX [A-S]). captive air training missiles from land.
(CATMs) against surface targets.
Some activities include firing a
missile with a high-explosive (HE)
warhead.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Other Training
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic.............. Submarine Sonar Maintenance of submarine sonar and Up to 1 hour..... LF5, MF3......... NBK Bangor, NBK 26 182
Maintenance. other system checks are conducted Bremerton, and
pierside or at sea. Offshore Area
>12 nmi from
land.
Acoustic.............. Surface Ship Maintenance of surface ship sonar Up to 4 hours.... MF1.............. NBK Bremerton, 25 175
Sonar and other system checks are NS Everett, and
Maintenance. conducted pierside or at sea. Offshore Area
>12 nmi from
land.
Acoustic.............. Unmanned Unmanned underwater vehicle Up to 24 hours... FLS2, M3......... Inland Waters, 60 420
Underwater certification involves training Offshore Area.
Vehicle Training. with unmanned platforms to ensure
submarine crew proficiency.
Tactical development involves
training with various payloads for
multiple purposes to ensure that
the systems can be employed
effectively in an operational
environment.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* (Counts only the explosive events).

Table 4--Proposed Testing Activities Analyzed for the Seven-Year Period in the NWTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual 7-Year
Stressor category Activity Description Typical duration Source bin Location # of # of
events events
--------------------------------------------------------------------------------------------------------------------------------------------------------
Naval Sea Systems Command Testing Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Anti-Submarine Warfare:
Acoustic.................. Anti-Submarine Ships and their 4-8 hours of active ASW1, ASW2, ASW3, Offshore Area..... 44 308
Warfare Testing. supporting sonar use. ASW5, MF1K, MF4,
platforms (rotary- MF5, MF10, MF11,
wing aircraft and MF12, TORP1.
unmanned aerial
systems) detect,
localize, and
prosecute
submarines.
Acoustic.................. At-Sea Sonar At-sea testing to From 4 hours to 11 ASW3, HF1, HF5, Offshore Area..... 4 28
Testing. ensure systems are days. M3, MF3. Inland Waters 4-6 34
fully functional in ASW3, HF5, TORP1.. (DBRC).
an open ocean
environment.
Acoustic.................. Countermeasure Countermeasure From 4 hours to 6 ASW3, ASW4, HF8, Offshore Area 14 98
Testing. testing involves days. MF1, TORP2. (QRS). ....... .......
the testing of ASW3, ASW4........ .................. 29 203
systems that will .................. Inland Waters ....... .......
detect, localize, ASW4.............. (DBRC, Keyport 1 5
and track incoming Range Site).
weapons, including Western Behm
marine vessel Canal, AK.
targets.
Countermeasures may
be systems to
obscure the
vessel's location
or systems to
rapidly detect,
track, and counter
incoming threats.
Testing includes
surface ship
torpedo defense
systems and marine
vessel stopping
payloads.

[[Page 33925]]

Acoustic.................. Pierside-Sonar Pierside testing to Up to 3 weeks...... ASW3, HF3, MF1, Inland Waters (NS 88-99 635
Testing. ensure systems are MF2, MF3, MF9, Everett, NBK
fully functional in MF10, MF12. Bangor, NBK
a controlled Bremerton).
pierside
environment prior
to at-sea test
activities.
Acoustic.................. Submarine Sonar Pierside, moored, Up to 3 weeks...... HF6, MF9.......... Western Behm 1-2 10
Testing/ and underway Canal, AK.
Maintenance. testing of
submarine systems
occurs periodically
following major
maintenance periods
and for routine
maintenance.
Acoustic; Explosive....... Torpedo (Explosive) Air, surface, or 1-2 hours during E8, E11, ASW3, Offshore Area >50 4 28
Testing. submarine crews daylight only. HF1, HF6, MF1, nmi from land.
employ explosive MF3, MF4, MF5,
and non-explosive MF6, TORP1, TORP2.
torpedoes against
artificial targets.
Acoustic.................. Torpedo (Non- Air, surface, or Up to 2 weeks...... ASW3, ASW4, HF1, Offshore Area..... 22 154
explosive) Testing. submarine crews HF5, HF6, MF1,
employ non- MF3, MF4, MF5,
explosive torpedoes MF6, MF9, MF10,
against targets, TORP1, TORP2.
submarines, or
surface vessels.
HF6, LF4, TORP1, Inland Waters 61 427
TORP2, TORP3. (DBRC).
Mine Warfare:
Acoustic; Explosive....... Mine Countermeasure Air, surface, and 1-10 days.......... E4, E7, HF4....... Offshore Area..... 3 15
and Neutralization subsurface vessels HF4............... Inland Waters..... 3 13
Testing. neutralize threat
mines and mine-like
objects.
Acoustic.................. Mine Detection and Air, surface, and Up to 24 days...... BB1, BB2, LF4..... Offshore Area 1 7
Classification subsurface vessels BB1, BB2, HF4, LF4 (QRS). 42 294
Testing. and systems detect Inland Waters
and classify mines (DBRC, Keyport
and mine-like Range Site).
objects. Vessels
also assess their
potential
susceptibility to
mines and mine-like
objects.
Unmanned Systems:
Acoustic.................. Unmanned Underwater Testing involves the Typically 1-2 days, FLS2, HF5, TORP1, Offshore Area 38-39 269
Vehicle Testing. production or up to multiple VHF1. (QRS). 371-379 2,615
upgrade of unmanned months. DS3, FLS2, HF5, Inland Waters
underwater HF9, M3, SAS2, (DBRC, Keyport
vehicles. This may VHF1, TORP1. Range Site, Carr
include testing of Inlet).
mission
capabilities (e.g.,
mine detection),
evaluating the
basic functions of
individual
platforms, or
conducting complex
events with
multiple vehicles.
Vessel Evaluation:
Acoustic.................. Undersea Warfare Ships demonstrate Up to 10 days...... ASW3, ASW4, HF4, Offshore Area..... 1-12 27
Testing. capability of MF1, MF4, MF5,
countermeasure MF6, MF9, TORP1,
systems and TORP2.
underwater
surveillance,
weapons engagement,
and communications
systems. This tests
ships' ability to
detect, track, and
engage undersea
targets.
Other Testing:
Acoustic.................. Acoustic and Research using Up to 14 days...... LF4, MF9.......... Offshore Area 1 7
Oceanographic active (QRS). 3 21
Research. transmissions from Inland Waters
sources deployed (DBRC, Keyport
from ships, Range Site).
aircraft, and
unmanned underwater
vehicles. Research
sources can be used
as proxies for
current and future
Navy systems.
Acoustic.................. Acoustic Component Various surface 1 day to multiple HF3, HF6, LF5, MF9 Western Behm 13-18 99
Testing. vessels, moored months. Canal, AK.
equipment, and
materials are
tested to evaluate
performance in the
marine environment.
Acoustic.................. Cold Water Support. Fleet training for 8 hours............ HF6............... Inland Waters 4 28
divers in a cold (Keyport Range ....... .......
water environment, Site, DBRC, Carr 1 7
and other diver Inlet).
training related to Western Behm
Navy divers Canal, AK.
supporting range/
test site
operations and
maintenance.

[[Page 33926]]

Acoustic.................. Post-Refit Sea Following periodic 8 hours............ HF9, M3, MF10..... Inland Waters 30 210
Trial. maintenance periods (DBRC).
or repairs, sea
trials are
conducted to
evaluate submarine
propulsion, sonar
systems, and other
mechanical tests.
Acoustic.................. Semi-Stationary Semi-stationary From 10 minutes to HF6, HF9, LF4, Inland Waters 120 840
Equipment Testing. equipment (e.g., multiple days. MF9, VHF2. (DBRC, Keyport ....... .......
hydrophones) is HF6, HF9.......... Range Site). 2-3 12
deployed to Western Behm
determine Canal, AK.
functionality.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Naval Air Systems Command Testing Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Anti-Submarine Warfare:
Acoustic; Explosive....... Tracking Test-- The test evaluates 4-8 flight hours... E1, E3, ASW2, Offshore Area..... 8 56
Maritime Patrol the sensors and ASW5, MF5, MF6.
Aircraft. systems used by
maritime patrol
aircraft to detect
and track
submarines and to
ensure that
aircraft systems
used to deploy the
tracking systems
perform to
specifications and
meet operational
requirements.
--------------------------------------------------------------------------------------------------------------------------------------------------------

Summary of Acoustic and Explosive Sources Analyzed for Training and
Testing

Tables 5 through 8 show the acoustic and explosive source classes,
bins, and quantity used in either hours or counts associated with the
Navy's proposed training and testing activities over a seven-year
period in the NWTT Study Area that were analyzed in the Navy's
rulemaking/LOA application. Table 5 describes the acoustic source
classes (i.e., low-frequency (LF), mid-frequency (MF), and high-
frequency (HF)) and numbers that could occur over seven years under the
proposed training activities. Acoustic source bin use in the proposed
activities would vary annually. The seven-year totals for the proposed
training activities take into account that annual variability.

Table 5--Acoustic Source Class Bins Analyzed and Numbers Used for Seven-Year Period for Training Activities in
the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
7-Year
Source class category Bin Description Unit Annual total
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF): Sources that LF5 LF sources less than H 1 5
produce signals less than 1 kHz. 180 dB.
Mid-Frequency (MF): Tactical and MF1 Hull-mounted surface H 164 1,148
non-tactical sources that produce ship sonars (e.g.,
signals between 1 and 10 kHz. AN/SQS-53C and AN/
SQS-61).
MF3 Hull-mounted H 70 490
submarine sonars
(e.g., AN/BQQ-10).
MF4 Helicopter-deployed H 0-1 1
dipping sonars
(e.g., AN/AQS-22 and
AN/AQS-13).
MF5 Active acoustic C 918-926 6,443
sonobuoys (e.g.,
DICASS).
MF11 Hull-mounted surface H 16 112
ship sonars with an
active duty cycle
greater than 80%.
High-Frequency (HF): Tactical and HF1 Hull-mounted H 48 336
non-tactical sources that produce submarine sonars
signals between 10 and 100 kHz. (e.g., AN/BQQ-10).
HF4 Mine detection, H 0-65 269
classification, and
neutralization sonar
(e.g., AN/SQS-20).
Anti-Submarine Warfare (ASW): ASW2 MF Multistatic Active C 350 2,450
Tactical sources (e.g., active Coherent sonobuoy
sonobuoys and acoustic (e.g., AN/SSQ-125).
countermeasures systems) used
during ASW training and testing
activities.
ASW3 MF towed active H 86 602
acoustic
countermeasure
systems (e.g., AN/
SLQ-25).
ASW5 MF sonobuoys with H 50 350
high duty cycles.
Torpedoes (TORP): Source classes TORP1 Lightweight torpedo C 16 112
associated with the active (e.g., MK 46, MK 54,
acoustic signals produced by or Anti-Torpedo
torpedoes. Torpedo).
TORP2 Heavyweight torpedo C 0-2 5
(e.g., MK 48).
Forward Looking Sonar (FLS): FLS2 HF sources with short H 240 1,680
Forward or upward looking object pulse lengths,
avoidance sonars used for ship narrow beam widths,
navigation and safety. and focused beam
patterns.

[[Page 33927]]

Acoustic Modems (M): Systems used M3 MF acoustic modems H 30 210
to transmit data through the water. (greater than 190
dB).
Synthetic Aperture Sonars (SAS): SAS2 HF SAS systems....... H 0-561 2,353
Sonars in which active acoustic
signals are post-processed to form
high-resolution images of the
seafloor.
----------------------------------------------------------------------------------------------------------------
Notes: H = hours; C = count.

Table 6 describes the acoustic source classes and numbers that
could occur over seven years under the proposed testing activities.
Acoustic source bin use in the proposed activities would vary annually.
The seven-year totals for the proposed testing activities take into
account that annual variability.

Table 6--Acoustic Source Class Bins Analyzed and Numbers Used for Seven-Year Period for Testing Activities in
the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
7-Year
Source class category Bin Description Unit Annual total
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF): Sources that LF4 LF sources equal to H 177 1,239
produce signals less than 1 kHz. 180 dB and up to 200
dB.
LF5 LF sources less than H 0-18 23
180 dB.
Mid-Frequency (MF): Tactical and MF1 Hull-mounted surface H 20-169 398
non-tactical sources that produce ship sonars (e.g.,
signals between 1 and 10 kHz. AN/SQS-53C and AN/
SQS-61).
MF1K Kingfisher mode H 48 336
associated with MF1
sonars.
MF2 Hull-mounted surface H 32 224
ship sonars (e.g.,
AN/SQS-56).
MF3 Hull-mounted H 34-36 239
submarine sonars
(e.g., AN/BQQ-10).
MF4 Helicopter-deployed H 41-50 298
dipping sonars
(e.g., AN/AQS-22 and
AN/AQS-13).
MF5 Active acoustic C 300-673 2,782
sonobuoys (e.g.,
DICASS).
MF6 Active underwater C 60-232 744
sound signal devices
(e.g., MK 84 SUS).
MF9 Active sources (equal H 644-959 5,086
to 180 dB and up to
200 dB) not
otherwise binned.
MF10 Active sources H 886 6,197
(greater than 160
dB, but less than
180 dB) not
otherwise binned.
MF11 Hull-mounted surface H 48 336
ship sonars with an
active duty cycle
greater than 80
percent.
MF12 Towed array surface H 100 700
ship sonars with an
active duty cycle
greater than 80
percent.
High-Frequency (HF): Tactical and HF1 Hull-mounted H 10 68
non-tactical sources that produce submarine sonars
signals between 10 and 100 kHz. (e.g., AN/BQQ-10).
HF3 Other hull-mounted H 1-19 30
submarine sonars
(classified).
HF4 Mine detection, H 1,860-1,868 11,235
classification, and
neutralization sonar
(e.g., AN/SQS-20).
HF5 Active sources H 352-400 2,608
(greater than 200
dB) not otherwise
binned.
HF6 Active sources (equal H 1,705-1,865 12,377
to 180 dB and up to
200 dB) not
otherwise binned.
HF8 Hull-mounted surface H 24 168
ship sonars (e.g.,
AN/SQS-61).
HF9 Weapon emulating H 257 1,772
sonar source.
Very High-Frequency (VHF): Tactical VHF1 Very high frequency H 320 2,240
and non-tactical sources that sources greater than
produce signals greater than 100 200 dB.
kHz but less than 200 kHz.
VHF2 Active sources with a H 135 945
frequency greater
than 100 kHz, up to
200 kHz with a
source level less
than 200 dB.
Anti-Submarine Warfare (ASW): ASW1 MF systems operating H 80 560
Tactical sources (e.g., active above 200 dB.
sonobuoys and acoustic
countermeasures systems) used
during ASW training and testing
activities.
ASW2 MF systems operating C 240 1,680
above 200 dB.
ASW3 MF towed active H 487-1,015 4,091
acoustic
countermeasure
systems (e.g., AN/
SLQ-25).

[[Page 33928]]

ASW4 MF expendable active C 1,349-1,389 9,442
acoustic device
countermeasures
(e.g., MK 3).
ASW5 MF sonobuoys with H 80 560
high duty cycles.
Torpedoes (TORP): Source classes TORP1 Lightweight torpedo C 298-360 2,258
associated with the active (e.g., MK 46, MK 54,
acoustic signals produced by or Anti-Torpedo
torpedoes. Torpedo).
TORP2 Heavyweight torpedo C 332-372 2,324
(e.g., MK 48).
TORP3 Heavyweight torpedo C 6 42
test (e.g., MK 48).
Forward Looking Sonar (FLS): FLS2 HF sources with short H 24 168
Forward or upward looking object pulse lengths,
avoidance sonars used for ship narrow beam widths,
navigation and safety. and focused beam
patterns.
Acoustic Modems (M): Systems used M3 MF acoustic modems H 1,088 7,616
to transmit data through the water. (greater than 190
dB).
Synthetic Aperture Sonars (SAS): SAS2 HF SAS systems....... H 1,312 9,184
Sonars in which active acoustic
signals are post-processed to form
high-resolution images of the
seafloor.
Broadband Sound Sources (BB): Sonar BB1 MF to HF mine H 48 336
systems with large frequency countermeasure sonar.
spectra, used for various purposes.
BB2 HF to VHF mine H 48 336
countermeasure sonar.
----------------------------------------------------------------------------------------------------------------
Notes: H = hours; C = count.

Table 7 describes the explosive source classes and numbers that
could occur over seven years under the proposed training activities.
Under the proposed activities bin use would vary annually, and the
seven-year totals for the proposed training activities take into
account that annual variability.

Table 7--Explosive Source Class Bins Analyzed and Numbers Used for Seven-Year Period for Training Activities in
the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Net explosive
Bin weight (lb) Example explosive source Annual 7-Year total
----------------------------------------------------------------------------------------------------------------
E1.................................... 0.1-0.25 Medium-caliber 60-120 672
projectiles.
E2.................................... >0.25-0.5 Medium-caliber 65-130 728
projectiles.
E3.................................... >0.5-2.5 Explosive Ordnance 6 42
Disposal Mine
Neutralization.
E5.................................... >5-10 Large-caliber projectile 56-112 628
E10................................... >250-500 1,000 lb bomb........... 0-4 9
----------------------------------------------------------------------------------------------------------------
Notes: (1) Net explosive weight refers to the equivalent amount of TNT. The actual weight of a munition may be
larger due to other components. lb = pound(s), ft = feet.

Table 8 describes the explosive source classes and numbers that
could occur over seven years under the proposed testing activities.
Under the proposed activities bin use would vary annually, and the
seven-year totals for the proposed testing activities take into account
that annual variability.

Table 8--Explosive Source Class Bins Analyzed and Numbers Used for Seven-Year Period for Testing Activities in
the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Net explosive
Bin weight (lb) Example explosive source Annual 7-Year total
----------------------------------------------------------------------------------------------------------------
E1.................................... 0.1-0.25 SUS buoy................ 8 56
E3.................................... >0.5-2.5 Explosive sonobuoy...... 72 504
E4.................................... >2.5-5 Mine Countermeasure and 36 180
Neutralization.
E7.................................... >20-60 Mine Countermeasure and 5 25
Neutralization.
E8.................................... >60-100 Lightweight torpedo..... 4 28
E11................................... >500-650 Heavyweight torpedo..... 4 28
----------------------------------------------------------------------------------------------------------------
Notes: (1) Net explosive weight refers to the equivalent amount of TNT. The actual weight of a munition may be
larger due to other components. lb = pound(s), ft = feet.

[[Page 33929]]

Vessel Movement

Vessels used as part of the proposed activities include ships,
submarines, unmanned vessels, and boats ranging in size from small, 22
ft rigid hull inflatable boats to aircraft carriers with lengths up to
1,092 ft. Large ships greater than 60 ft generally operate at speeds in
the range of 10-15 kn for fuel conservation. Submarines generally
operate at speeds in the range of 8-13 kn in transits and less than
those speeds for certain tactical maneuvers. Small craft (for purposes
of this discussion--less than 60 ft in length) have much more variable
speeds (dependent on the mission). While these speeds are
representative of most events, some vessels need to temporarily operate
outside of these parameters. For example, to produce the required
relative wind speed over the flight deck, an aircraft carrier engaged
in flight operations must adjust its speed through the water
accordingly. Conversely, there are other instances, such as launch and
recovery of a small rigid hull inflatable boat; vessel boarding,
search, and seizure training events; or retrieval of a target when
vessels will be dead in the water or moving slowly ahead to maintain
steerage.
The number of military vessels used in the NWTT Study Area varies
based on military training and testing requirements, deployment
schedules, annual budgets, and other unpredictable factors. Many
training and testing activities involve the use of vessels. These
activities could be widely dispersed throughout the NWTT Study Area,
but would be typically conducted near naval ports, piers, and range
areas. Training and testing activities involving vessel movements occur
intermittently and are variable in duration, ranging from a few hours
to up to two weeks. There is no seasonal differentiation in military
vessel use. Large vessel movement primarily occurs with the majority of
the traffic flowing between the installations and the Operating Areas
(OPAREAS). Smaller support craft would be more concentrated in the
coastal waters in the areas of naval installations, ports, and ranges.
The number of activities that include the use of vessels for training
events is lower (approximately 10 percent) than the number for testing
activities. Testing can occur jointly with a training event, in which
case that testing activity could be conducted from a training vessel.
Additionally, a variety of smaller craft will be operated within
the NWTT Study Area. Small craft types, sizes, and speeds vary. During
training and testing, speeds generally range from 10-14 kn; however,
vessels can and will, on occasion, operate within the entire spectrum
of their specific operational capabilities. In all cases, the vessels/
craft will be operated in a safe manner consistent with the local
conditions.

Standard Operating Procedures

For training and testing to be effective, personnel must be able to
safely use their sensors and weapon systems as they are intended to be
used in military missions and combat operations and to their optimum
capabilities. While standard operating procedures are designed for the
safety of personnel and equipment and to ensure the success of training
and testing activities, their implementation often yields benefits to
environmental, socioeconomic, public health and safety, and cultural
resources.
Navy standard operating procedures have been developed and refined
over years of experience and are broadcast via numerous naval
instructions and manuals, including, but not limited to the following
materials:
Ship, submarine, and aircraft safety manuals;
Ship, submarine, and aircraft standard operating manuals;
Fleet Area Control and Surveillance Facility range
operating instructions;
Fleet exercise publications and instructions;
Naval Sea Systems Command test range safety and standard
operating instructions;
Navy-instrumented range operating procedures;
Naval shipyard sea trial agendas;
Research, development, test, and evaluation plans;
Naval gunfire safety instructions;
Navy planned maintenance system instructions and
requirements;
Federal Aviation Administration regulations; and
International Regulations for Preventing Collisions at
Sea.
Because standard operating procedures are essential to safety and
mission success, the Navy considers them to be part of the proposed
Specified Activities, and has included them in the environmental
analysis. Standard operating procedures that are recognized as having a
potential benefit to marine mammals during training and testing
activities are noted below and discussed in more detail within the 2019
NWTT DSEIS/OEIS.
Vessel Safety;
Weapons Firing Procedures;
Target Deployment Safety; and
Towed In-Water Device Safety.
Standard operating procedures (which are implemented regardless of
their secondary benefits) are different from mitigation measures (which
are designed entirely for the purpose of avoiding or reducing
environmental impacts). Information on mitigation measures is provided
in the Proposed Mitigation section below. Additional information on
standard operating procedures is presented in Section 2.3.3 (Standard
Operating Procedures) in the 2019 NWTT DSEIS/OEIS.

Description of Marine Mammals and Their Habitat in the Area of the
Specified Activities

Marine mammal species and their associated stocks that have the
potential to occur in the NWTT Study Area are presented in Table 9
along with an abundance estimate, an associated coefficient of
variation value, and best and minimum abundance estimates. The Navy
requests authorization to take individuals of 29 marine mammal species
by Level A harassment and Level B harassment incidental to training and
testing activities from the use of sonar and other transducers and in-
water detonations. In addition, the Navy requests authorization for
three takes of large whales by serious injury or mortality from vessel
strikes over the seven-year period. Currently, the Southern Resident
killer whale has critical habitat designated under the Endangered
Species Act (ESA) in the NWTT Study Area (described below). However,
NMFS has recently published two proposed rules, proposing new or
revised ESA-designated critical habitat for humpback whales (84 FR
54354; October 9, 2019) and Southern Resident killer whales (84 FR
49214; September 19, 2019).
Information on the status, distribution, abundance, population
trends, habitat, and ecology of marine mammals in the NWTT Study Area
may be found in Chapter 4 of the Navy's rulemaking/LOA application.
NMFS has reviewed this information and found it to be accurate and
complete. Additional information on the general biology and ecology of
marine mammals is included in the 2019 NWTT DSEIS/OEIS. Table 9
incorporates data from the U.S. Pacific and the Alaska Marine Mammal
Stock Assessment Reports (SARs; Carretta et al., 2019; Muto et al.,
2019) and the most recent revised data in the draft SARs (see https://www.fisheries.noaa .gov/national/marine-mammal-protection/draft-marine-
mammal-stock-assessment-reports); as well as incorporates the best
available science, including monitoring data from the Navy's marine
mammal research efforts.

[[Page 33930]]

Species Not Included in the Analysis

The species carried forward for analysis (and described in Table 9
below) are those likely to be found in the NWTT Study Area based on the
most recent data available, and do not include species that may have
once inhabited or transited the area but have not been sighted in
recent years (e.g., species which were extirpated from factors such as
19th and 20th century commercial exploitation). Several species that
may be present in the northwest Pacific Ocean have an extremely low
probability of presence in the NWTT Study Area. These species are
considered extralimital (not anticipated to occur in the Study Area) or
rare (occur in the Study Area sporadically, but sightings are rare).
These species/stocks include the Eastern North Pacific stock of Bryde's
whale (Balaenoptera edeni), Eastern North Pacific stock of North
Pacific right whale (Eubalaena japonica), false killer whale (Pseudorca
crassidens), long-beaked common dolphin (Delphinus capensis), Western
U.S. stock of Steller sea lion (Eumetopias jubatus), and Alaska stock
of Cuvier's beaked whale (Ziphius cavirostris). Despite rare stranding
or sighting reports, the Study Area is outside the normal range of the
Eastern North Pacific stock of Bryde's whale and the California stock
of the long-beaked common dolphin. The Study Area is also outside the
normal range of the false killer whale's distribution in the Pacific
Ocean. The Eastern North Pacific stock of North Pacific right whale is
estimated to have an abundance of 31 individuals (Muto et al., 2020)
and is anticipated to be extremely rare in the Study Area. The Western
U.S. stock of Steller sea lions is considered rare in the Offshore Area
of the Study Area, and is not expected to occur in the Inland Waters
portion of the Study Area. In Western Behm Canal, there is a low
probability of juvenile male Steller sea lion occurrence from the
Western U.S. stock, however these individuals are anticipated to be
very rare. Finally, the Alaska stock of Cuvier's beaked whales is not
expected to occur in either the Offshore Area or Inland Waters of the
NWTT Study Area, and are considered extralimital in Western Behm Canal
as this area does not overlap with their range of distribution. NMFS
agrees with the Navy's assessment that these species are unlikely to
occur in the NWTT Study Area and they are not discussed further.

Table 9--Marine Mammal Occurrence Within the NWTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
ESA/MMPA Stock abundance Occurrence
status; (CV, Nmin, most Annual --------------------------------------
Common name Scientific name Stock strategic recent abundance PBR M/SI 3
(Y/N) 1 survey) 2 Offshore Inland Western
area waters Behm Canal
--------------------------------------------------------------------------------------------------------------------------------------------------------
Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae:
Gray whale............... Eschrichtius Eastern North -, -, N 26.960 (0.05, 801 139 Seasonal... Seasonal... ...........
robustus. Pacific. 25,849, 2016).
Family Balaenopteridae
(rorquals):
Blue whale............... Balaenoptera Eastern North E, D, S 1,496 (0.44, 1.2 >=19.4 Seasonal...
musculus. Pacific. 1,050, 2014).
Fin whale................ Balaenoptera Northeast E, D, S 3,168 (0.26, 5.1 0.4 Rare.
physalus. Pacific. 2,554, 2013)
\4\.
CA/OR/WA........ E, D, S 9,029 (0.12, 81 >=43.5 Seasonal... Rare....... ...........
8,127, 2014).
Humpback whale........... Megaptera Central North T/E,\5\ D, 10,103 (0.3, 83 25 Regular.... Regular.... Regular.
novaeangliae. Pacific. S 7,891, 2006).
CA/OR/WA........ T/E,\5\ D, 2,900 (0.05, 16.7 >=42.1 Regular.... Regular.... Regular.
S 2,784, 2014).
Minke whale.............. Balaenoptera Alaska.......... -, -, N UNK............. UND 0 Rare.
acutorostrata.
CA/OR/WA........ -, -, N 636 (0.72, 369, 3.5 >=1.3 Regular.... Seasonal...
2014).
Sei whale................ Balaenoptera Eastern North E, D, S 519 (0.4, 374, 0.75 >=0.2 Regular.... ........... ...........
borealis. Pacific. 2014).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Physeteridae:
Sperm whale.............. Physeter CA/OR/WA........ E, D, S 1.997 (0.57, 2.5 0.4 Rare.......
macrocephalus. 1,270, 2014).
Family Kogiidae:
Dwarf sperm whale........ Kogia sima...... CA/OR/WA........ -, -, N UNK............. UND 0 Rare.......
Pygmy sperm whale........ Kogia breviceps. CA/OR/WA........ -, -, N 4,111 (1.12, 19.2 0 Regular....
1,924, 2014).
Family Ziphiidae (beaked
whales):
Baird's beaked whale..... Berardius CA/OR/WA........ -, -, N 2,697 (0.6, 16 0 Regular....
bairdii. 1,633, 2014).
Cuvier's beaked whale.... Ziphius CA/OR/WA........ -, -, N 3,274 (0.67, 21 < 0.1 Regular....
cavirostris. 2,059, 2014).
3Mesoplodont beaked whales... Mesoplodon CA/OR/WA........ -, -, N 3,044 (0.54, 20 0.1 Regular....
species. 1,967, 2014).
Family Delphinidae:
Common bottlenose dolphin Tursiops CA/OR/WA -, -, N 1,924 (0.54, 11 >=1.6 Regular....
truncatus. Offshore. 1,255, 2014).
Killer whale............. Orcinus orca.... Eastern North -, -, N 2,347 (UNK, 24 1 Regular.
Pacific Alaskan 2,347, 2012)
Resident. \6\.
Eastern North -, -, N 302 (UNK, 302, 2.2 0.2 Seasonal... Seasonal... ...........
Pacific 2018) \6\.
Northern
Resident.
West Coast -, -, N 243 (UNK, 243, 2.4 0 Regular.... Regular.... Regular.
Transient. 2009).
Eastern North -, -, N 300 (0.1, 276, 2.8 0 Regular.... Regular.
Pacific 2012).
Offshore.
Eastern North E, D, Y 75 (NA, 75, 0.13 0 Seasonal... Regular.... ...........
Pacific 2018).
Southern
Resident.
Northern right whale Lissodelphus CA/OR/WA........ -, -, N 26,556 (0.44, 179 3.8 Regular....
dolphin. borealis. 18,608, 2014).
Pacific white-sided Lagenorhynchus North Pacific... -, -, N 26,880 (UNK, NA, UND 0 Regular.
dolphin. obliquidens. 1990).
CA/OR/WA........ -, -, N 26,814 (0.28, 191 7.5 Regular.... Regular.... ...........
21,195, 2014).
Risso's dolphin.......... Grampus griseus. CA/OR/WA........ -, -, N 6,336 (0.32, 46 >=3.7 Regular.... Rare....... ...........
4,817, 2014).
Short-beaked common Delphinus CA/OR/WA........ -, -, N 969,861 (0.17, 8,393 [egr]40 Regular.... Rare....... ...........
dolphin. delphis. 839,325, 2014).
Short-finned pilot whale. Globicephala CA/OR/WA........ -, -, N 836 (0.79, 466, 4.5 1.2 Regular.... Rare....... ...........
macrorhynchus. 2014).
Striped dolphin.......... Stenella CA/OR/WA........ -, -, N 29,211 (0.2, 238 >=0.8 Regular....
coeruleoalba. 24,782, 2014).
Family Phocoenidae
(porpoises):
Dall's porpoise.......... Phocoenoides Alaska.......... -, -, N 83,400 (0.097, UND 38 Regular.
dalli. NA, 1991).

[[Page 33931]]

CA/OR/WA........ -, -, N 25,750 (0.45, 172 0.3 Regular.... Regular.... ...........
17,954, 2014).
Harbor porpoise.......... Phocoena Southeast Alaska -, -, Y 1,354 (0.12, 12 34 Regular.
phocoena. 1,224, 2012).
Northern OR/WA -, -, N 21,487 (0.44, 151 >=3 Regular....
Coast. 15, 123, 2011).
Northern CA/ -, -, N 35,769 (0.52, 475 >=0.6 Regular....
Southern OR. 23,749, 2011).
Washington -, -, N 11,233 (0.37, 66 >=7.2 Regular.... ...........
Inland Waters. 8,308, 2015).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals
and sea lions):
California sea lion...... Zalophus U.S............. -, -, N 257,606 (NA, 14,011 >=321 Seasonal... Regular.... ...........
californianus. 233,515, 2014).
Guadalupe fur seal....... Arctocephalus Mexico to T, D, Y 34,187 (NA, 1,062 >=3.8 Seasonal...
townsendi. California. 31,109, 2013).
Northern fur seal........ Callorhinus Eastern Pacific. -, D, Y 620,660 (0.2, 11,295 399 Regular.... Seasonal.
ursinus. 525,333, 2016).
California...... -, -, N 14,050 (NA, 451 1.8 Regular....
7,524, 2013).
Steller sea lion......... Eumetopias Eastern U.S..... -, -, N 43,201 (NA, 2,592 113 Regular.... Seasonal... Regular.
jubatus. 43,201, 2017)
\7\.
Family Phocidae (earless
seals):
Harbor seal.............. Phoca vitulina.. Southeast Alaska -, -, N 27,659 (UNK, 746 40 Regular.
(Clarence 24,854, 2015).
Strait).
OR/WA Coast..... -, -, N UNK............. UND 10.6 Regular.... Seasonal... ...........
California...... -, -, N 30,968 (0.157, 1,641 43 Regular....
27,348, 2012).
Washington -, -, N UNK............. UND 9.8 Seasonal... Regular.... ...........
Northern Inland
Waters.
Hood Canal...... -, -, N UNK............. UND 0.2 Seasonal... Regular.... ...........
Southern Puget -, -, N UNK............. UND 3.4 Seasonal... Regular.... ...........
Sound.
Northern Elephant seal... Mirounga California...... -, -, N 179,000 (NA, 4,882 8.8 Regular.... Regular.... Seasonal.
angustirostris. 81,368, 2010).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds potential biological removal (PBR) or which is determined to be declining and likely to be listed under the ESA within the foreseeable future.
Any species or stock listed under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-
assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For the Eastern
North Pacific Southern Resident stock of killer whales Nbest/Nmin are based on a direct count of individually identifiable animals. The population
size of the U.S. stock of California sea lion was estimated from a 1975-2014 time series of pup counts (Lowry et al. 2017), combined with mark-
recapture estimates of survival rates (DeLong et al. 2017, Laake et al. 2018). The population size of the Mexico to California stock of Guadalupe fur
seals was estimated from pup count data collected in 2013 and a range of correction factors applied to pup counts to account for uncounted age classes
and pre-census pup mortality (Garc[iacute]a-Aguilar et al. 2018). The population size of the California stock of Northern fur seals was estimated from
pup counts multiplied by an expansion factor (San Miguel Island) and maximum pup, juvenile, and adult counts (Farrallon Islands) at rookeries. The
population size of the Eastern U.S. stock of Steller sea lions was estimated from pup counts and non-pup counts at rookeries in Southeast Alaska,
British Columbia, Oregon, and California. The population size of the California stock of Northern Elephant seals was estimated from pup counts at
rookeries multiplied by the inverse of the expected ratio of pups to total animals (McCann, 1985; Lowry et al., 2014).
\3\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality and serious injury (M/SI) from all sources combined (e.g.,
commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
associated with estimated mortality due to commercial fisheries is presented in some cases.
\4\ SAR reports this stock abundance assessment as provisional and notes that it is an underestimate for the entire stock because it is based on surveys
which covered only a small portion of the stock's range.
\5\ Humpback whales in the Central North Pacific stock and the CA/OR/WA stock are from three Distinct Population Segments (DPSs) based on animals
identified in breeding areas in Hawaii, Mexico, and Central America. Both stocks and all three DPSs co-occur in the NWTT Study Area.
\6\ Stock abundance estimate is based on counts of individual animals identified from photo-identification catalogues. Surveys for abundance estimates
of these stocks are conducted infrequently.
\7\ Stock abundance estimate is the best estimate counts, which have not been corrected to account for animals at sea during abundance surveys.
Note--Unknown (UNK); Undetermined (UND); Not Applicable (NA); California (CA); Oregon (OR); Washington (WA).

Below, we include additional information about the marine mammals
in the area of the Specified Activities that informs our analysis, such
as identifying known areas of important habitat or behaviors, or where
Unusual Mortality Events (UME) have been designated.

Critical Habitat

Currently, only the distinct population segment (DPS) of Southern
Resident killer whale (SRKW) has ESA-designated critical habitat in the
NWTT Study Area. NMFS has recently published two proposed rules,
however, proposing new or revised ESA-designated critical habitat for
SRKW (84 FR 49214; September 19, 2019) and humpback whales (84 FR
54354; October 9, 2019).
NMFS designated critical habitat for the SRKW DPS on November 29,
2006 (71 FR 69054) in inland waters of Washington State. Based on the
natural history of the SRKWs and their habitat needs, NMFS identified
physical or biological features essential to the conservation of the
SRKW DPS: (1) Water quality to support growth and development; (2) prey
species of sufficient quantity, quality, and availability to support
individual growth, reproduction and development, as well as overall
population growth; and (3) passage conditions to allow for migration,
resting, and foraging. ESA-designated critical habitat consists of
three areas: (1) The Summer Core Area in Haro Strait and waters around
the San Juan Islands; (2) Puget Sound; and (3) the Strait of Juan de
Fuca, which comprise approximately 2,560 square miles (mi\2\) (6,630
square kilometers (km\2\)) of marine habitat. In designating critical
habitat, NMFS considered economic impacts and impacts to national
security, and concluded the benefits of exclusion of 18 military sites,
comprising approximately 112 mi\2\ (291 km\2\), outweighed the benefits
of inclusion because of national security impacts.
On January 21, 2014, NMFS received a petition requesting revisions
to the SRKW critical habitat designation. The petition requested NMFS
revise critical habitat to include ``inhabited marine waters along the
West Coast of the United States that constitute essential foraging and
wintering areas,'' specifically the region between Cape Flattery,
Washington and Point Reyes, California extending from the coast to a
distance of 47.2 mi (76 km) offshore.

[[Page 33932]]

The petition also requested NMFS adopt a fourth essential habitat
feature in both current and expanded critical habitat relating to in-
water sound levels. On September 19, 2019 (84 FR 54354), NMFS published
a proposed rule proposing to revise the critical habitat designation
for the SRKW DPS by designating six new areas (using the same essential
features determined in 2006) along the U.S. West Coast. Specific new
areas proposed along the U.S. West Coast include 15,626.6 mi\2\
(40,472.7 km\2\) of marine waters between the 6.1 m (20 ft) depth
contour and the 200 m (656.2 ft) depth contour from the U.S.
international border with Canada south to Point Sur, California.
On March 15, 2018, several non-governmental organizations filed a
lawsuit seeking court-ordered deadlines for the issuance of proposed
and final rules to designate ESA critical habitat for the Central
American, Mexico, and Western North Pacific DPSs of humpback whales. In
2018, NMFS convened a critical habitat review team to assess and
evaluate information in support of critical habitat designation for
these DPSs. On October 9, 2019 (84 FR 54354), NMFS published a proposed
rule proposing ESA-designated critical habitat areas located off the
coasts of California, Oregon, Washington, and Alaska, including areas
within the NWTT Study Area. Based on consideration of national security
and economic impacts, NMFS also proposed to exclude multiple areas from
the designation for each DPS.

Biologically Important Areas

Biologically Important Areas (BIAs) include areas of known
importance for reproduction, feeding, or migration, or areas where
small and resident populations are known to occur (Van Parijs, 2015).
Unlike ESA critical habitat, these areas are not formally designated
pursuant to any statute or law, but are a compilation of the best
available science intended to inform impact and mitigation analyses. An
interactive map of the BIAs may be found here: https://cetsound.noaa.gov/biologically-important-area-map.
BIAs off the West Coast of the continental United States with the
potential to overlap portions of the NWTT Study Area include the
following feeding and migration areas: Northern Puget Sound Feeding
Area for gray whales (March-May); Northwest Feeding Area for gray
whales (May-November); Northbound Migration Phase A for gray whales
(January-July); Northbound Migration Phase B for gray whales (March-
July); Northern Washington Feeding Area for humpback whales (May-
November); Stonewall and Heceta Bank Feeding Area for humpback whales
(May-November); and Point St. George Feeding Area for humpback whales
(July-November) (Calambokidis et al., 2015).
When comparing the geographic area of the NWTT Study Area with the
BIAs off the West Coast of the continental United States, there is no
direct spatial overlap between the Study Area and four of the offshore
gray whale feeding areas--Grays Harbor, WA; Depoe Bay, OR; Cape Blanco
and Orford Reef, OR; and Pt. St. George, CA. The NWTT Study Area does
overlap with the Northwest WA gray whale feeding area and the Northern
Puget Sound gray whale feeding area. There is no overlap of the gray
whale migration corridor BIAs and the NWTT Study Area, with the
exception of a portion of the Northwest coast of Washington
approximately from Pacific Beach and extending north to the Strait of
Juan de Fuca. The offshore Northern WA humpback whale feeding area is
located entirely within the NWTT Study Area boundaries. The humpback
whale feeding area at Stonewall and Hecta Bank only partially overlaps
with the Study Area, and the feeding area at Point St. George has
extremely limited overlap with the Study Area. All proposed activities
occurring in the Offshore Area of the Study Area could potentially
occur in these BIAs, except activities limited to greater than 50 nmi
from shore (as described in the Proposed Mitigation Measures section).
To mitigate impacts to marine mammals in these BIAs, the Navy would
implement several procedural mitigation measures and mitigation areas
(described in the Proposed Mitigation Measures section).

National Marine Sanctuaries

Under Title III of the Marine Protection, Research, and Sanctuaries
Act of 1972 (also known as the National Marine Sanctuaries Act (NMSA)),
NOAA can establish as national marine sanctuaries (NMS), areas of the
marine environment with special conservation, recreational, ecological,
historical, cultural, archaeological, scientific, educational, or
aesthetic qualities. Sanctuary regulations prohibit or regulate
activities that could destroy, cause the loss of, or injure sanctuary
resources pursuant to the regulations for that sanctuary and other
applicable law (15 CFR part 922). NMSs are managed on a site-specific
basis, and each sanctuary has site-specific regulations. Most, but not
all, sanctuaries have site-specific regulatory exemptions from the
prohibitions for certain military activities. Separately, section
304(d) of the NMSA requires Federal agencies to consult with the Office
of National Marine Sanctuaries whenever their activities are likely to
destroy, cause the loss of, or injure a sanctuary resource. One NMS,
the Olympic Coast NMS managed by the Office of National Marine
Sanctuaries, is located within the offshore portion of the NWTT Study
Area (for a map of the location of this NMS see Chapter 6 of the 2019
NWTT DSEIS/OEIS and Figure 6-1).
The Olympic Coast NMS includes 3,188 mi\2\ of marine waters and
submerged lands off the Olympic Peninsula coastline. The sanctuary
extends 25-50 mi. (40.2-80.5 km) seaward, covering much of the
continental shelf and portions of three major submarine canyons. The
boundaries of the sanctuary as defined in the Olympic Coast NMS
regulations (15 CFR part 922, subpart O) extend from Koitlah Point, due
north to the United States/Canada international boundary, and seaward
to the 100-fathom isobath (approximately 180 m in depth). The seaward
boundary of the sanctuary follows the 100-fathom isobath south to a
point due west of Copalis River, and cuts across the tops of Nitinat,
Juan de Fuca, and the Quinault Canyons. The shoreward boundary of the
sanctuary is at the mean lower low-water line when adjacent to American
Indian lands and state lands, and includes the intertidal areas to the
mean higher high-water line when adjacent to federally managed lands.
When adjacent to rivers and streams, the sanctuary boundary cuts across
the mouths but does not extend up river or up stream. The Olympic Coast
NMS includes many types of productive marine habitats including kelp
forests, subtidal reefs, rocky and sand intertidal zones, submarine
canyons, rocky deep-sea habitat, and plankton-rich upwelling zones.
These habitats support the Sanctuary's rich biodiversity which includes
29 species of marine mammals that reside in or migrate through the
Sanctuary (Office of National Marine Sanctuaries 2008). Additional
information on the Olympic Coast NMS can be found at https://olympiccoast.noaa.gov.

Unusual Mortality Events (UMEs)

An UME is defined under Section 410(6) of the MMPA as a stranding
that is unexpected; involves a significant die-off of any marine mammal
population; and demands immediate response. Three UMEs with ongoing
investigations in the NWTT Study Area that inform our analysis are
discussed below. The California sea lion UME in

[[Page 33933]]

California is still open, but will be closed soon. The Guadalupe fur
seal UME in California and the gray whale UME along the west coast of
North America are active and involve ongoing investigations.
California Sea Lion UME
From January 2013 through September 2016, a greater than expected
number of young malnourished California sea lions (Zalophus
californianus) stranded along the coast of California. Sea lions
stranding from an early age (6-8 months old) through two years of age
(hereafter referred to as juveniles) were consistently underweight
without other disease processes detected. Of the 8,122 stranded
juveniles attributed to the UME, 93 percent stranded alive (n = 7,587,
with 3,418 of these released after rehabilitation) and 7 percent (n =
531) stranded dead. Several factors are hypothesized to have impacted
the ability of nursing females and young sea lions to acquire adequate
nutrition for successful pup rearing and juvenile growth. In late 2012,
decreased anchovy and sardine recruitment (CalCOFI data, July 2013) may
have led to nutritionally stressed adult females. Biotoxins were
present at various times throughout the UME, and while they were not
detected in the stranded juvenile sea lions (whose stomachs were empty
at the time of stranding), biotoxins may have impacted the adult
females' ability to support their dependent pups by affecting their
cognitive function (e.g., navigation, behavior towards their
offspring). Therefore, the role of biotoxins in this UME, via its
possible impact on adult females' ability to support their pups, is
unclear. The proposed primary cause of the UME was malnutrition of sea
lion pups and yearlings due to ecological factors. These factors
included shifts in distribution, abundance and/or quality of sea lion
prey items around the Channel Island rookeries during critical sea lion
life history events (nursing by adult females, and transitioning from
milk to prey by young sea lions). These prey shifts were most likely
driven by unusual oceanographic conditions at the time due to the
``Warm Water Blob'' and El Ni[ntilde]o. This investigation will soon be
closed. Please refer to: https://www.fisheries.noaa.gov/national/
marine-life-distress/2013-2017-california-sea-lion-unusual-mortality-
event-california for more information on this UME.
Guadalupe Fur Seal UME
Increased strandings of Guadalupe fur seals began along the entire
coast of California in January 2015 and were eight times higher than
the historical average (approximately 10 seals/yr). Strandings have
continued since 2015 and remained well above average through 2019.
Numbers by year are as follows: 2015 (98), 2016 (76), 2017 (62), 2018
(45), 2019 (116), 2020 (3 as of March 6, 2020). The total number of
Guadalupe fur seals stranding in California from January 1, 2015,
through March 6, 2020, in the UME is 400. Additionally, strandings of
Guadalupe fur seals became elevated in the spring of 2019 in Washington
and Oregon; subsequently, strandings for seals in these two states have
been added to the UME starting from January 1, 2019. The current total
number of strandings in Washington and Oregon is 94 seals, including 91
in 2019 and 3 in 2020 of 3/6/2020. Strandings are seasonal and
generally peak in April through June of each year. The Guadalupe fur
seal strandings have been mostly weaned pups and juveniles (1-2 years
old) with both live and dead strandings occurring. Current findings
from the majority of stranded animals include primary malnutrition with
secondary bacterial and parasitic infections. The California portion of
this UME was occurring in the same area as the 2013-2016 California sea
lion UME. This investigation is ongoing. Please refer to: https://www.fisheries.noaa.gov/national/marine-life-distress/2015-2019-
guadalupe-fur-seal-unusual-mortality-event-california for more
information on this UME.
Gray Whale UME
Since January 1, 2019, elevated gray whale strandings have occurred
along the west coast of North America, from Mexico to Canada. As of
March 13, 2020, there have been a total of 264 strandings along the
coasts of the United States, Canada, and Mexico, with 129 of those
strandings occurring along the U.S. coast. Of the strandings on the
U.S. coast, 48 have occurred in Alaska, 35 in Washington, 6 in Oregon,
and 40 in California. Partial necropsy examinations conducted on a
subset of stranded whales have shown evidence of poor to thin body
condition. As part of the UME investigation process, NOAA is assembling
an independent team of scientists to coordinate with the Working Group
on Marine Mammal Unusual Mortality Events to review the data collected,
sample stranded whales, and determine the next steps for the
investigation. Please refer to: https://www.fisheries.noaa.gov/
national/marine-life-distress/2019-gray-whale-unusual-mortality-event-
along-west-coast for more information on this UME.

Marine Mammal Hearing

Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Current data indicate that not all marine
mammal species have equal hearing capabilities (e.g., Richardson et
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect
this, Southall et al. (2007) recommended that marine mammals be divided
into functional hearing groups based on directly measured or estimated
hearing ranges on the basis of available behavioral response data,
audiograms derived using auditory evoked potential techniques,
anatomical modeling, and other data. Note that no direct measurements
of hearing ability have been successfully completed for mysticetes
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65 dB
threshold from the normalized composite audiograms, with the exception
for lower limits for low-frequency cetaceans where the lower bound was
deemed to be biologically implausible and the lower bound from Southall
et al. (2007) retained. The functional groups and the associated
frequencies are indicated below (note that these frequency ranges
correspond to the range for the composite group, with the entire range
not necessarily reflecting the capabilities of every species within
that group):
Low-frequency cetaceans (mysticetes): Generalized hearing
is estimated to occur between approximately 7 Hz and 35 kHz;
Mid-frequency cetaceans (larger toothed whales, beaked
whales, and most delphinids): Generalized hearing is estimated to occur
between approximately 150 Hz and 160 kHz;
High-frequency cetaceans (porpoises, river dolphins, and
members of the genera Kogia and Cephalorhynchus; including two members
of the genus Lagenorhynchus, on the basis of recent echolocation data
and genetic data): Generalized hearing is estimated to occur between
approximately 275 Hz and 160 kHz;
Pinnipeds in water; Phocidae (true seals): Generalized
hearing is estimated to occur between approximately 50 Hz to 86 kHz;
and

[[Page 33934]]

Pinnipeds in water; Otariidae (eared seals): Generalized
hearing is estimated to occur between 60 Hz and 39 kHz.
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt,
2013).
For more details concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of the available
information.

Potential Effects of Specified Activities on Marine Mammals and Their
Habitat

This section includes a discussion of the ways that components of
the specified activity may impact marine mammals and their habitat. The
Estimated Take of Marine Mammals section later in this rule includes a
quantitative analysis of the number of instances of take that could
occur from these activities. The Preliminary Analysis and Negligible
Impact Determination section considers the content of this section, the
Estimated Take of Marine Mammals section, and the Proposed Mitigation
Measures section to draw conclusions regarding the likely impacts of
these activities on the reproductive success or survivorship of
individuals and whether those impacts on individuals are likely to
adversely affect the species through effects on annual rates of
recruitment or survival.
The Navy has requested authorization for the take of marine mammals
that may occur incidental to training and testing activities in the
NWTT Study Area. The Navy analyzed potential impacts to marine mammals
from acoustic and explosive sources and from vessel use in its
rulemaking/LOA application. NMFS carefully reviewed the information
provided by the Navy along with independently reviewing applicable
scientific research and literature and other information to evaluate
the potential effects of the Navy's activities on marine mammals, which
are presented in this section.
Other potential impacts to marine mammals from training and testing
activities in the NWTT Study Area were analyzed in the 2019 NWTT DSEIS/
OEIS, in consultation with NMFS as a cooperating agency, and determined
to be unlikely to result in marine mammal take. This includes serious
injury or mortality from explosives. Therefore, the Navy has not
requested authorization for take of marine mammals incidental to other
components of their proposed Specified Activities, and we agree that
incidental take is unlikely to occur from those components. In this
proposed rule, NMFS analyzes the potential effects on marine mammals
from the activity components that may cause the take of marine mammals:
Exposure to acoustic or explosive stressors including non-impulsive
(sonar and other transducers) and impulsive (explosives) stressors and
vessel movement.
For the purpose of MMPA incidental take authorizations, NMFS'
effects assessments serve four primary purposes: (1) To determine
whether the specified activities would have a negligible impact on the
affected species or stocks of marine mammals (based on whether it is
likely that the activities would adversely affect the species or stocks
through effects on annual rates of recruitment or survival); (2) to
determine whether the specified activities would have an unmitigable
adverse impact on the availability of the species or stocks for
subsistence uses; (3) to prescribe the permissible methods of taking
(i.e., Level B harassment (behavioral harassment and temporary
threshold shift (TTS)), Level A harassment (permanent threshold shift
(PTS) and non-auditory injury), serious injury, or mortality),
including identification of the number and types of take that could
occur by harassment, serious injury, or mortality, and to prescribe
other means of effecting the least practicable adverse impact on the
species or stocks and their habitat (i.e., mitigation measures); and
(4) to prescribe requirements pertaining to monitoring and reporting.
In this section, NMFS provides a description of the ways marine
mammals may be generally affected by these activities in the form of
mortality, physical trauma, sensory impairment (permanent and temporary
threshold shifts and acoustic masking), physiological responses
(particular stress responses), behavioral disturbance, or habitat
effects. Explosives and vessel strikes, which have the potential to
result in incidental take from serious injury and/or mortality, will be
discussed in more detail in the Estimated Take of Marine Mammals
section. The Estimated Take of Marine Mammals section also discusses
how the potential effects on marine mammals from non-impulsive and
impulsive sources relate to the MMPA definitions of Level A Harassment
and Level B Harassment, and quantifies those effects that rise to the
level of a take. The Preliminary Analysis and Negligible Impact
Determination section assesses whether the proposed authorized take
would have a negligible impact on the affected species and stocks.

Potential Effects of Underwater Sound

Anthropogenic sounds cover a broad range of frequencies and sound
levels and can have a range of highly variable impacts on marine life,
from none or minor to potentially severe responses, depending on
received levels, duration of exposure, behavioral context, and various
other factors. The potential effects of underwater sound from active
acoustic sources can possibly result in one or more of the following:
Temporary or permanent hearing impairment, non-auditory physical or
physiological effects, behavioral disturbance, stress, and masking
(Richardson et al., 1995; Gordon et al., 2004; Nowacek et al., 2007;
Southall et al., 2007; G[ouml]tz et al., 2009, Southall et al., 2019a).
The degree of effect is intrinsically related to the signal
characteristics, received level, distance from the source, and duration
of the sound exposure. In general, sudden, high level sounds can cause
hearing loss, as can longer exposures to lower level sounds. Temporary
or permanent loss of hearing can occur after exposure to noise, and
occurs almost exclusively for noise within an animal's hearing range.
Note that in the following discussion, we refer in many cases to a
review article concerning studies of noise-induced hearing loss
conducted from 1996-2015 (i.e., Finneran, 2015). For study-specific
citations, please see that work. We first describe general
manifestations of acoustic effects before providing discussion specific
to the Navy's activities.
Richardson et al. (1995) described zones of increasing intensity of
effect that might be expected to occur, in relation to distance from a
source and assuming that the signal is within an animal's hearing
range. First is the area within which the acoustic signal would be
audible (potentially perceived) to the animal, but not strong enough to
elicit any overt behavioral or physiological response. The next zone
corresponds with the area where the signal is audible to the animal and
of sufficient intensity to elicit behavioral or physiological
responsiveness. Third is a zone within which, for signals of high
intensity, the received level is sufficient to potentially cause
discomfort or tissue damage to auditory systems. Overlaying these zones
to a certain extent is the area within which masking (i.e., when a
sound interferes with or masks the ability of an animal to detect a
signal of interest that is above the absolute hearing threshold) may
occur; the

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masking zone may be highly variable in size.
We also describe more severe potential effects (i.e., certain non-
auditory physical or physiological effects). Potential effects from
impulsive sound sources can range in severity from effects such as
behavioral disturbance or tactile perception to physical discomfort,
slight injury of the internal organs and the auditory system, or
mortality (Yelverton et al., 1973). Non-auditory physiological effects
or injuries that theoretically might occur in marine mammals exposed to
high level underwater sound or as a secondary effect of extreme
behavioral reactions (e.g., change in dive profile as a result of an
avoidance reaction) caused by exposure to sound include neurological
effects, bubble formation, resonance effects, and other types of organ
or tissue damage (Cox et al., 2006; Southall et al., 2007; Zimmer and
Tyack, 2007; Tal et al., 2015).

Acoustic Sources

Direct Physiological Effects
Non-impulsive sources of sound can cause direct physiological
effects including noise-induced loss of hearing sensitivity (or
``threshold shift''), nitrogen decompression, acoustically-induced
bubble growth, and injury due to sound-induced acoustic resonance. Only
noise-induced hearing loss is anticipated to occur due to the Navy's
activities. Acoustically-induced (or mediated) bubble growth and other
pressure-related physiological impacts are addressed briefly below, but
are not expected to result from the Navy's activities. Separately, an
animal's behavioral reaction to an acoustic exposure might lead to
physiological effects that might ultimately lead to injury or death,
which is discussed later in the Stranding subsection.

Hearing Loss--Threshold Shift

Marine mammals exposed to high-intensity sound, or to lower-
intensity sound for prolonged periods, can experience hearing threshold
shift, which is the loss of hearing sensitivity at certain frequency
ranges after cessation of sound (Finneran, 2015). Threshold shift can
be permanent (PTS), in which case the loss of hearing sensitivity is
not fully recoverable, or temporary (TTS), in which case the animal's
hearing threshold would recover over time (Southall et al., 2007). TTS
can last from minutes or hours to days (i.e., there is recovery back to
baseline/pre-exposure levels), can occur within a specific frequency
range (i.e., an animal might only have a temporary loss of hearing
sensitivity within a limited frequency band of its auditory range), and
can be of varying amounts (e.g., an animal's hearing sensitivity might
be reduced by only 6 dB or reduced by 30 dB). While there is no simple
functional relationship between TTS and PTS or other auditory injury
(e.g., neural degeneration), as TTS increases, the likelihood that
additional exposure sound pressure level (SPL) or duration will result
in PTS or other injury also increases (see also the 2019 NWTT DSEIS/
OEIS for additional discussion). Exposure thresholds for the occurrence
of PTS or other auditory injury can therefore be defined based on a
specific amount of TTS; that is, although an exposure has been shown to
produce only TTS, we assume that any additional exposure may result in
some PTS or other injury. The specific upper limit of TTS is based on
experimental data showing amounts of TTS that have not resulted in PTS
or injury. In other words, we do not need to know the exact functional
relationship between TTS and PTS or other injury, we only need to know
the upper limit for TTS before some PTS or injury is possible. In
severe cases of PTS, there can be total or partial deafness, while in
most cases the animal has an impaired ability to hear sounds in
specific frequency ranges (Kryter, 1985).
When PTS occurs, there is physical damage to the sound receptors in
the ear (i.e., tissue damage), whereas TTS represents primarily tissue
fatigue and is reversible (Southall et al., 2007). PTS is permanent
(i.e., there is incomplete recovery back to baseline/pre-exposure
levels), but also can occur in a specific frequency range and amount as
mentioned above for TTS. In addition, other investigators have
suggested that TTS is within the normal bounds of physiological
variability and tolerance and does not represent physical injury (e.g.,
Ward, 1997). Therefore, NMFS does not consider TTS to constitute
auditory injury.
The following physiological mechanisms are thought to play a role
in inducing auditory threshold shift: Effects to sensory hair cells in
the inner ear that reduce their sensitivity; modification of the
chemical environment within the sensory cells; residual muscular
activity in the middle ear; displacement of certain inner ear
membranes; increased blood flow; and post-stimulatory reduction in both
efferent and sensory neural output (Southall et al., 2007). The
amplitude, duration, frequency, temporal pattern, and energy
distribution of sound exposure all can affect the amount of associated
threshold shift and the frequency range in which it occurs. Generally,
the amount of threshold shift, and the time needed to recover from the
effect, increase as amplitude and duration of sound exposure increases.
Human non-impulsive noise exposure guidelines are based on the
assumption that exposures of equal energy (the same sound exposure
level (SEL)) produce equal amounts of hearing impairment regardless of
how the sound energy is distributed in time (NIOSH, 1998). Previous
marine mammal TTS studies have also generally supported this equal
energy relationship (Southall et al., 2007). However, some more recent
studies concluded that for all noise exposure situations the equal
energy relationship may not be the best indicator to predict TTS onset
levels (Mooney et al., 2009a and 2009b; Kastak et al., 2007). These
studies highlight the inherent complexity of predicting TTS onset in
marine mammals, as well as the importance of considering exposure
duration when assessing potential impacts. Generally, with sound
exposures of equal energy, those that were quieter (lower SPL) with
longer duration were found to induce TTS onset at lower levels than
those of louder (higher SPL) and shorter duration. Less threshold shift
will occur from intermittent sounds than from a continuous exposure
with the same energy (some recovery can occur between intermittent
exposures) (Kryter et al., 1966; Ward, 1997; Mooney et al., 2009a,
2009b; Finneran et al., 2010). For example, one short but loud (higher
SPL) sound exposure may induce the same impairment as one longer but
softer (lower SPL) sound, which in turn may cause more impairment than
a series of several intermittent softer sounds with the same total
energy (Ward, 1997). Additionally, though TTS is temporary, very
prolonged or repeated exposure to sound strong enough to elicit TTS, or
shorter-term exposure to sound levels well above the TTS threshold can
cause PTS, at least in terrestrial mammals (Kryter, 1985; Lonsbury-
Martin et al., 1987).
PTS is considered auditory injury (Southall et al., 2007).
Irreparable damage to the inner or outer cochlear hair cells may cause
PTS; however, other mechanisms are also involved, such as exceeding the
elastic limits of certain tissues and membranes in the middle and inner
ears and resultant changes in the chemical composition of the inner ear
fluids (Southall et al., 2007).
The NMFS Acoustic Technical Guidance (NMFS, 2018), which was used
in the assessment of effects for this rule, compiled, interpreted, and

[[Page 33936]]

synthesized the best available scientific information for noise-induced
hearing effects for marine mammals to derive updated thresholds for
assessing the impacts of noise on marine mammal hearing. More recently,
Southall et al. (2019a) evaluated Southall et al. (2007) and used
updated scientific information to propose revised noise exposure
criteria to predict onset of auditory effects in marine mammals (i.e.,
PTS and TTS onset). Southall et al. (2019a) note that the quantitative
processes described and the resulting exposure criteria (i.e.,
thresholds and auditory weighting functions) are largely identical to
those in Finneran (2016) and NMFS (2018). They only differ in that the
Southall et al. (2019a) exposure criteria are more broadly applicable
as they include all marine mammal species (rather than only those under
NMFS jurisdiction) for all noise exposures (both in air and underwater
for amphibious species) and, while the hearing group compositions are
identical, they renamed the hearing groups.
Many studies have examined noise-induced hearing loss in marine
mammals (see Finneran (2015) and Southall et al. (2019a) for
summaries), however for cetaceans, published data on the onset of TTS
are limited to the captive bottlenose dolphin, beluga, harbor porpoise,
and Yangtze finless porpoise, and for pinnipeds in water, measurements
of TTS are limited to harbor seals, elephant seals, and California sea
lions. These studies examine hearing thresholds measured in marine
mammals before and after exposure to intense sounds. The difference
between the pre-exposure and post-exposure thresholds can then be used
to determine the amount of threshold shift at various post-exposure
times. NMFS has reviewed the available studies, which are summarized
below (see also the 2019 NWTT DSEIS/OEIS which includes additional
discussion on TTS studies related to sonar and other transducers).
The method used to test hearing may affect the resulting
amount of measured TTS, with neurophysiological measures producing
larger amounts of TTS compared to psychophysical measures (Finneran et
al., 2007; Finneran, 2015).
The amount of TTS varies with the hearing test frequency.
As the exposure SPL increases, the frequency at which the maximum TTS
occurs also increases (Kastelein et al., 2014b). For high-level
exposures, the maximum TTS typically occurs one-half to one octave
above the exposure frequency (Finneran et al., 2007; Mooney et al.,
2009a; Nachtigall et al., 2004; Popov et al., 2011; Popov et al., 2013;
Schlundt et al., 2000). The overall spread of TTS from tonal exposures
can therefore extend over a large frequency range (i.e., narrowband
exposures can produce broadband (greater than one octave) TTS).
The amount of TTS increases with exposure SPL and duration
and is correlated with SEL, especially if the range of exposure
durations is relatively small (Kastak et al., 2007; Kastelein et al.,
2014b; Popov et al., 2014). As the exposure duration increases,
however, the relationship between TTS and SEL begins to break down.
Specifically, duration has a more significant effect on TTS than would
be predicted on the basis of SEL alone (Finneran et al., 2010a; Kastak
et al., 2005; Mooney et al., 2009a). This means if two exposures have
the same SEL but different durations, the exposure with the longer
duration (thus lower SPL) will tend to produce more TTS than the
exposure with the higher SPL and shorter duration. In most acoustic
impact assessments, the scenarios of interest involve shorter duration
exposures than the marine mammal experimental data from which impact
thresholds are derived; therefore, use of SEL tends to over-estimate
the amount of TTS. Despite this, SEL continues to be used in many
situations because it is relatively simple, more accurate than SPL
alone, and lends itself easily to scenarios involving multiple
exposures with different SPL.
Gradual increases of TTS may not be directly observable
with increasing exposure levels, before the onset of PTS (Reichmuth et
al., 2019). Similarly, PTS can occur without measurable behavioral
modifications (Reichmuth et al., 2019).
The amount of TTS depends on the exposure frequency.
Sounds at low frequencies, well below the region of best sensitivity,
are less hazardous than those at higher frequencies, near the region of
best sensitivity (Finneran and Schlundt, 2013). The onset of TTS--
defined as the exposure level necessary to produce 6 dB of TTS (i.e.,
clearly above the typical variation in threshold measurements)--also
varies with exposure frequency. At low frequencies, onset-TTS exposure
levels are higher compared to those in the region of best sensitivity.
TTS can accumulate across multiple exposures, but the
resulting TTS will be less than the TTS from a single, continuous
exposure with the same SEL (Finneran et al., 2010a; Kastelein et al.,
2014b; Kastelein et al., 2015b; Mooney et al., 2009b). This means that
TTS predictions based on the total, cumulative SEL will overestimate
the amount of TTS from intermittent exposures such as sonars and
impulsive sources.
The amount of observed TTS tends to decrease with
increasing time following the exposure; however, the relationship is
not monotonic (i.e., increasing exposure does not always increase TTS).
The time required for complete recovery of hearing depends on the
magnitude of the initial shift; for relatively small shifts recovery
may be complete in a few minutes, while large shifts (e.g.,
approximately 40 dB) may require several days for recovery. Under many
circumstances TTS recovers linearly with the logarithm of time
(Finneran et al., 2010a, 2010b; Finneran and Schlundt, 2013; Kastelein
et al., 2012a; Kastelein et al., 2012b; Kastelein et al., 2013a;
Kastelein et al., 2014b; Kastelein et al., 2014c; Popov et al., 2011;
Popov et al., 2013; Popov et al., 2014). This means that for each
doubling of recovery time, the amount of TTS will decrease by the same
amount (e.g., 6 dB recovery per doubling of time).
Nachtigall et al. (2018) and Finneran (2018) describe the
measurements of hearing sensitivity of multiple odontocete species
(bottlenose dolphin, harbor porpoise, beluga, and false killer whale)
when a relatively loud sound was preceded by a warning sound. These
captive animals were shown to reduce hearing sensitivity when warned of
an impending intense sound. Based on these experimental observations of
captive animals, the authors suggest that wild animals may dampen their
hearing during prolonged exposures or if conditioned to anticipate
intense sounds. Finneran recommends further investigation of the
mechanisms of hearing sensitivity reduction in order to understand the
implications for interpretation of existing TTS data obtained from
captive animals, notably for considering TTS due to short duration,
unpredictable exposures.
Marine mammal hearing plays a critical role in communication with
conspecifics and in interpretation of environmental cues for purposes
such as predator avoidance and prey capture. Depending on the degree
(elevation of threshold in dB), duration (i.e., recovery time), and
frequency range of TTS, and the context in which it is experienced, TTS
can have effects on marine mammals ranging from discountable to serious
similar to those discussed in auditory masking, below. For example, a
marine mammal may be able to readily compensate for a brief, relatively
small amount of TTS in a non-critical frequency range that takes place
during

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a time where ambient noise is lower and there are not as many competing
sounds present. Alternatively, a larger amount and longer duration of
TTS sustained during a time when communication is critical for
successful mother/calf interactions could have more serious impacts if
it were in the same frequency band as the necessary vocalizations and
of a severity that impeded communication. The fact that animals exposed
to high levels of sound that would be expected to result in this
physiological response would also be expected to have behavioral
responses of a comparatively more severe or sustained nature is
potentially more significant than simple existence of a TTS. However,
it is important to note that TTS could occur due to longer exposures to
sound at lower levels so that a behavioral response may not be
elicited.
Depending on the degree and frequency range, the effects of PTS on
an animal could also range in severity, although it is considered
generally more serious than TTS because it is a permanent condition. Of
note, reduced hearing sensitivity as a simple function of aging has
been observed in marine mammals, as well as humans and other taxa
(Southall et al., 2007), so we can infer that strategies exist for
coping with this condition to some degree, though likely not without
some cost to the animal.

Acoustically-Induced Bubble Formation Due to Sonars and Other Pressure-
Related Impacts

One theoretical cause of injury to marine mammals is rectified
diffusion (Crum and Mao, 1996), the process of increasing the size of a
bubble by exposing it to a sound field. This process could be
facilitated if the environment in which the ensonified bubbles exist is
supersaturated with gas. Repetitive diving by marine mammals can cause
the blood and some tissues to accumulate gas to a greater degree than
is supported by the surrounding environmental pressure (Ridgway and
Howard, 1979). The deeper and longer dives of some marine mammals (for
example, beaked whales) are theoretically predicted to induce greater
supersaturation (Houser et al., 2001b). If rectified diffusion were
possible in marine mammals exposed to high-level sound, conditions of
tissue supersaturation could theoretically speed the rate and increase
the size of bubble growth. Subsequent effects due to tissue trauma and
emboli would presumably mirror those observed in humans suffering from
decompression sickness.
It is unlikely that the short duration (in combination with the
source levels) of sonar pings would be long enough to drive bubble
growth to any substantial size, if such a phenomenon occurs. However,
an alternative but related hypothesis has also been suggested: Stable
bubbles could be destabilized by high-level sound exposures such that
bubble growth then occurs through static diffusion of gas out of the
tissues. In such a scenario the marine mammal would need to be in a
gas-supersaturated state for a long enough period of time for bubbles
to become of a problematic size. Recent research with ex vivo
supersaturated bovine tissues suggested that, for a 37 kHz signal, a
sound exposure of approximately 215 dB referenced to (re) 1 [mu]Pa
would be required before microbubbles became destabilized and grew
(Crum et al., 2005). Assuming spherical spreading loss and a nominal
sonar source level of 235 dB re: 1 [mu]Pa at 1 m, a whale would need to
be within 10 m (33 ft) of the sonar dome to be exposed to such sound
levels. Furthermore, tissues in the study were supersaturated by
exposing them to pressures of 400-700 kilopascals for periods of hours
and then releasing them to ambient pressures. Assuming the
equilibration of gases with the tissues occurred when the tissues were
exposed to the high pressures, levels of supersaturation in the tissues
could have been as high as 400-700 percent. These levels of tissue
supersaturation are substantially higher than model predictions for
marine mammals (Houser et al., 2001; Saunders et al., 2008). It is
improbable that this mechanism is responsible for stranding events or
traumas associated with beaked whale strandings because both the degree
of supersaturation and exposure levels observed to cause microbubble
destabilization are unlikely to occur, either alone or in concert.
Yet another hypothesis (decompression sickness) has speculated that
rapid ascent to the surface following exposure to a startling sound
might produce tissue gas saturation sufficient for the evolution of
nitrogen bubbles (Jepson et al., 2003; Fernandez et al., 2005;
Fern[aacute]ndez et al., 2012). In this scenario, the rate of ascent
would need to be sufficiently rapid to compromise behavioral or
physiological protections against nitrogen bubble formation.
Alternatively, Tyack et al. (2006) studied the deep diving behavior of
beaked whales and concluded that: ``Using current models of breath-hold
diving, we infer that their natural diving behavior is inconsistent
with known problems of acute nitrogen supersaturation and embolism.''
Collectively, these hypotheses can be referred to as ``hypotheses of
acoustically mediated bubble growth.''
Although theoretical predictions suggest the possibility for
acoustically mediated bubble growth, there is considerable disagreement
among scientists as to its likelihood (Piantadosi and Thalmann, 2004;
Evans and Miller, 2003; Cox et al., 2006; Rommel et al., 2006). Crum
and Mao (1996) hypothesized that received levels would have to exceed
190 dB in order for there to be the possibility of significant bubble
growth due to supersaturation of gases in the blood (i.e., rectified
diffusion). Work conducted by Crum et al. (2005) demonstrated the
possibility of rectified diffusion for short duration signals, but at
SELs and tissue saturation levels that are highly improbable to occur
in diving marine mammals. To date, energy levels (ELs) predicted to
cause in vivo bubble formation within diving cetaceans have not been
evaluated (NOAA, 2002b). Jepson et al. (2003, 2005) and Fernandez et
al. (2004, 2005, 2012) concluded that in vivo bubble formation, which
may be exacerbated by deep, long-duration, repetitive dives may explain
why beaked whales appear to be relatively vulnerable to MF/HF sonar
exposures. It has also been argued that traumas from some beaked whale
strandings are consistent with gas emboli and bubble-induced tissue
separations (Jepson et al., 2003); however, there is no conclusive
evidence of this (Rommel et al., 2006). Based on examination of sonar-
associated strandings, Bernaldo de Quiros et al. (2019) list diagnostic
features, the presence of all of which suggest gas and fat embolic
syndrome for beaked whales stranded in association with sonar exposure.
As described in additional detail in the Nitrogen Decompression
subsection of the 2019 NWTT DSEIS/OEIS, marine mammals generally are
thought to deal with nitrogen loads in their blood and other tissues,
caused by gas exchange from the lungs under conditions of high ambient
pressure during diving, through anatomical, behavioral, and
physiological adaptations (Hooker et al., 2012). Although not a direct
injury, variations in marine mammal diving behavior or avoidance
responses have been hypothesized to result in nitrogen off-gassing in
super-saturated tissues, possibly to the point of deleterious vascular
and tissue bubble formation (Hooker et al., 2012; Jepson et al., 2003;
Saunders et al., 2008) with resulting symptoms similar to decompression
sickness, however the process is still not well understood.

[[Page 33938]]

In 2009, Hooker et al. tested two mathematical models to predict
blood and tissue tension N2 (PN2) using field data from
three beaked whale species: Northern bottlenose whales, Cuvier's beaked
whales, and Blainville's beaked whales. The researchers aimed to
determine if physiology (body mass, diving lung volume, and dive
response) or dive behavior (dive depth and duration, changes in ascent
rate, and diel behavior) would lead to differences in PN2
levels and thereby decompression sickness risk between species. In
their study, they compared results for previously published time depth
recorder data (Hooker and Baird, 1999; Baird et al., 2006, 2008) from
Cuvier's beaked whale, Blainville's beaked whale, and northern
bottlenose whale. They reported that diving lung volume and extent of
the dive response had a large effect on end-dive PN2. Also,
results showed that dive profiles had a larger influence on end-dive
PN2 than body mass differences between species. Despite diel
changes (i.e., variation that occurs regularly every day or most days)
in dive behavior, PN2 levels showed no consistent trend.
Model output suggested that all three species live with tissue
PN2 levels that would cause a significant proportion of
decompression sickness cases in terrestrial mammals. The authors
concluded that the dive behavior of Cuvier's beaked whale was different
from both Blainville's beaked whale and northern bottlenose whale, and
resulted in higher predicted tissue and blood N2 levels (Hooker et al.,
2009). They also suggested that the prevalence of Cuvier's beaked
whales stranding after naval sonar exercises could be explained by
either a higher abundance of this species in the affected areas or by
possible species differences in behavior and/or physiology related to
MF active sonar (Hooker et al., 2009).
Bernaldo de Quiros et al. (2012) showed that, among stranded
whales, deep diving species of whales had higher abundances of gas
bubbles compared to shallow diving species. Kvadsheim et al. (2012)
estimated blood and tissue PN2 levels in species
representing shallow, intermediate, and deep diving cetaceans following
behavioral responses to sonar and their comparisons found that deep
diving species had higher end-dive blood and tissue N2
levels, indicating a higher risk of developing gas bubble emboli
compared with shallow diving species. Fahlmann et al. (2014) evaluated
dive data recorded from sperm, killer, long-finned pilot, Blainville's
beaked and Cuvier's beaked whales before and during exposure to low-
frequency (1-2 kHz), as defined by the authors, and mid-frequency (2-7
kHz) active sonar in an attempt to determine if either differences in
dive behavior or physiological responses to sonar are plausible risk
factors for bubble formation. The authors suggested that CO2
may initiate bubble formation and growth, while elevated levels of
N2 may be important for continued bubble growth. The authors
also suggest that if CO2 plays an important role in bubble
formation, a cetacean escaping a sound source may experience increased
metabolic rate, CO2 production, and alteration in cardiac
output, which could increase risk of gas bubble emboli. However, as
discussed in Kvadsheim et al. (2012), the actual observed behavioral
responses to sonar from the species in their study (sperm, killer,
long-finned pilot, Blainville's beaked, and Cuvier's beaked whales) did
not imply any significantly increased risk of decompression sickness
due to high levels of N2. Therefore, further information is
needed to understand the relationship between exposure to stimuli,
behavioral response (discussed in more detail below), elevated
N2 levels, and gas bubble emboli in marine mammals. The
hypotheses for gas bubble formation related to beaked whale strandings
is that beaked whales potentially have strong avoidance responses to MF
active sonars because they sound similar to their main predator, the
killer whale (Cox et al., 2006; Southall et al., 2007; Zimmer and
Tyack, 2007; Baird et al., 2008; Hooker et al., 2009). Further
investigation is needed to assess the potential validity of these
hypotheses.
To summarize, while there are several hypotheses, there is little
data directly connecting intense, anthropogenic underwater sounds with
non-auditory physical effects in marine mammals. The available data do
not support identification of a specific exposure level above which
non-auditory effects can be expected (Southall et al., 2007) or any
meaningful quantitative predictions of the numbers (if any) of marine
mammals that might be affected in these ways. In addition, such
effects, if they occur at all, would be expected to be limited to
situations where marine mammals were exposed to high powered sounds at
very close range over a prolonged period of time, which is not expected
to occur based on the speed of the vessels operating sonar in
combination with the speed and behavior of marine mammals in the
vicinity of sonar.

Injury Due to Sonar-Induced Acoustic Resonance

An object exposed to its resonant frequency will tend to amplify
its vibration at that frequency, a phenomenon called acoustic
resonance. Acoustic resonance has been proposed as a potential
mechanism by which a sonar or sources with similar operating
characteristics could damage tissues of marine mammals. In 2002, NMFS
convened a panel of government and private scientists to investigate
the potential for acoustic resonance to occur in marine mammals
(National Oceanic and Atmospheric Administration, 2002). They modeled
and evaluated the likelihood that Navy mid-frequency sonar (2-10 kHz)
caused resonance effects in beaked whales that eventually led to their
stranding. The workshop participants concluded that resonance in air-
filled structures was not likely to have played a primary role in the
Bahamas stranding in 2000. They listed several reasons supporting this
finding including (among others): Tissue displacements at resonance are
estimated to be too small to cause tissue damage; tissue-lined air
spaces most susceptible to resonance are too large in marine mammals to
have resonant frequencies in the ranges used by mid-frequency or low-
frequency sonar; lung resonant frequencies increase with depth, and
tissue displacements decrease with depth so if resonance is more likely
to be caused at depth it is also less likely to have an affect there;
and lung tissue damage has not been observed in any mass, multi-species
stranding of beaked whales. The frequency at which resonance was
predicted to occur in the animals' lungs was 50 Hz, well below the
frequencies used by the mid-frequency sonar systems associated with the
Bahamas event. The workshop participants focused on the March 2000
stranding of beaked whales in the Bahamas as high-quality data were
available, but the workshop report notes that the results apply to
other sonar-related stranding events. For the reasons given by the 2002
workshop participants, we do not anticipate injury due to sonar-induced
acoustic resonance from the Navy's proposed activities.
Physiological Stress
There is growing interest in monitoring and assessing the impacts
of stress responses to sound in marine animals. Classic stress
responses begin when an animal's central nervous system perceives a
potential threat to its homeostasis. That perception triggers stress
responses regardless of whether a

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stimulus actually threatens the animal; the mere perception of a threat
is sufficient to trigger a stress response (Moberg, 2000; Sapolsky et
al., 2005; Seyle, 1950). Once an animal's central nervous system
perceives a threat, it mounts a biological response or defense that
consists of a combination of the four general biological defense
responses: Behavioral responses, autonomic nervous system responses,
neuroendocrine responses, or immune responses.
According to Moberg (2000), in the case of many stressors, an
animal's first and sometimes most economical (in terms of biotic costs)
response is behavioral avoidance of the potential stressor or avoidance
of continued exposure to a stressor. An animal's second line of defense
to stressors involves the sympathetic part of the autonomic nervous
system and the classical ``fight or flight'' response which includes
the cardiovascular system, the gastrointestinal system, the exocrine
glands, and the adrenal medulla to produce changes in heart rate, blood
pressure, and gastrointestinal activity that humans commonly associate
with ``stress.'' These responses have a relatively short duration and
may or may not have significant long-term effect on an animal's
welfare.
An animal's third line of defense to stressors involves its
neuroendocrine systems or sympathetic nervous systems; the system that
has received the most study has been the hypothalmus-pituitary-adrenal
system (also known as the HPA axis in mammals or the hypothalamus-
pituitary-interrenal axis in fish and some reptiles). Unlike stress
responses associated with the autonomic nervous system, virtually all
neuro-endocrine functions that are affected by stress--including immune
competence, reproduction, metabolism, and behavior--are regulated by
pituitary hormones. Stress-induced changes in the secretion of
pituitary hormones have been implicated in failed reproduction (Moberg,
1987; Rivier and Rivest, 1991), altered metabolism (Elasser et al.,
2000), reduced immune competence (Blecha, 2000), and behavioral
disturbance (Moberg, 1987; Blecha, 2000). Increases in the circulation
of glucocorticosteroids (cortisol, corticosterone, and aldosterone in
marine mammals; see Romano et al., 2004) have been equated with stress
for many years.
The primary distinction between stress (which is adaptive and does
not normally place an animal at risk) and distress is the biotic cost
of the response. During a stress response, an animal uses glycogen
stores that can be quickly replenished once the stress is alleviated.
In such circumstances, the cost of the stress response would not pose
serious fitness consequences. However, when an animal does not have
sufficient energy reserves to satisfy the energetic costs of a stress
response, energy resources must be diverted from other biotic
functions, which impairs those functions that experience the diversion.
For example, when a stress response diverts energy away from growth in
young animals, those animals may experience stunted growth. When a
stress response diverts energy from a fetus, an animal's reproductive
success and its fitness will suffer. In these cases, the animals will
have entered a pre-pathological or pathological state which is called
``distress'' (Seyle, 1950) or ``allostatic loading'' (McEwen and
Wingfield, 2003). This pathological state of distress will last until
the animal replenishes its energetic reserves sufficiently to restore
normal function. Note that these examples involved a long-term (days or
weeks) stress response exposure to stimuli.
Relationships between these physiological mechanisms, animal
behavior, and the costs of stress responses are well-studied through
controlled experiments in both laboratory and free-ranging animals (for
examples see, Holberton et al., 1996; Hood et al., 1998; Jessop et al.,
2003; Krausman et al., 2004; Lankford et al., 2005; Reneerkens et al.,
2002; Thompson and Hamer, 2000). However, it should be noted (and as is
described in additional detail in the 2019 NWTT DSEIS/OEIS) that our
understanding of the functions of various stress hormones (for example,
cortisol), is based largely upon observations of the stress response in
terrestrial mammals. Atkinson et al., 2015 note that the endocrine
response of marine mammals to stress may not be the same as that of
terrestrial mammals because of the selective pressures marine mammals
faced during their evolution in an ocean environment. For example, due
to the necessity of breath-holding while diving and foraging at depth,
the physiological role of epinephrine and norepinephrine (the
catecholamines) in marine mammals might be different than in other
mammals.
Marine mammals naturally experience stressors within their
environment and as part of their life histories. Changing weather and
ocean conditions, exposure to disease and naturally occurring toxins,
lack of prey availability, and interactions with predators all
contribute to the stress a marine mammal experiences (Atkinson et al.,
2015). Breeding cycles, periods of fasting, and social interactions
with members of the same species are also stressors, although they are
natural components of an animal's life history. Anthropogenic
activities have the potential to provide additional stressors beyond
those that occur naturally (Fair et al., 2014; Meissner et al., 2015;
Rolland et al., 2012). Anthropogenic stressors potentially include such
things as fishery interactions, pollution, tourism, and ocean noise.
Acoustically induced stress in marine mammals is not well
understood. There are ongoing efforts to improve our understanding of
how stressors impact marine mammal populations (e.g., King et al.,
2015; New et al., 2013a; New et al., 2013b; Pirotta et al., 2015a),
however little data exist on the consequences of sound-induced stress
response (acute or chronic). Factors potentially affecting a marine
mammal's response to a stressor include the individual's life history
stage, sex, age, reproductive status, overall physiological and
behavioral plasticity, and whether they are na[iuml]ve or experienced
with the sound (e.g., prior experience with a stressor may result in a
reduced response due to habituation (Finneran and Branstetter, 2013;
St. Aubin and Dierauf, 2001a)). Stress responses due to exposure to
anthropogenic sounds or other stressors and their effects on marine
mammals have been reviewed (Fair and Becker, 2000; Romano et al.,
2002b) and, more rarely, studied in wild populations (e.g., Romano et
al., 2002a). For example, Rolland et al. (2012) found that noise
reduction from reduced ship traffic in the Bay of Fundy was associated
with decreased stress in North Atlantic right whales. These and other
studies lead to a reasonable expectation that some marine mammals will
experience physiological stress responses upon exposure to acoustic
stressors and that it is possible that some of these would be
classified as ``distress.'' In addition, any animal experiencing TTS
would likely also experience stress responses (NRC, 2003).
Other research has also investigated the impact from vessels (both
whale-watching and general vessel traffic noise), and demonstrated
impacts do occur (Bain, 2002; Erbe, 2002; Lusseau, 2006; Williams et
al., 2006; Williams et al., 2009; Noren et al., 2009; Read et al.,
2014; Rolland et al., 2012; Skarke et al., 2014; Williams et al., 2013;
Williams et al., 2014a; Williams et al., 2014b; Pirotta et al., 2015).
This body of research has generally investigated impacts associated
with the presence of chronic stressors, which differ significantly from
the proposed Navy training and testing

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vessel activities in the NWTT Study Area. For example, in an analysis
of energy costs to killer whales, Williams et al. (2009) suggested that
whale-watching in Canada's Johnstone Strait resulted in lost feeding
opportunities due to vessel disturbance, which could carry higher costs
than other measures of behavioral change might suggest. Ayres et al.
(2012) reported on research in the Salish Sea (Washington state)
involving the measurement of southern resident killer whale fecal
hormones to assess two potential threats to the species recovery: Lack
of prey (salmon) and impacts to behavior from vessel traffic. Ayres et
al. (2012) suggested that the lack of prey overshadowed any population-
level physiological impacts on southern resident killer whales from
vessel traffic. In a conceptual model developed by the Population
Consequences of Acoustic Disturbance (PCAD) working group, serum
hormones were identified as possible indicators of behavioral effects
that are translated into altered rates of reproduction and mortality
(NRC, 2005). The Office of Naval Research hosted a workshop (Effects of
Stress on Marine Mammals Exposed to Sound) in 2009 that focused on this
topic (ONR, 2009). Ultimately, the PCAD working group issued a report
(Cochrem, 2014) that summarized information compiled from 239 papers or
book chapters relating to stress in marine mammals and concluded that
stress responses can last from minutes to hours and, while we typically
focus on adverse stress responses, stress response is part of a natural
process to help animals adjust to changes in their environment and can
also be either neutral or beneficial.
Most sound-induced stress response studies in marine mammals have
focused on acute responses to sound either by measuring catecholamines
or by measuring heart rate as an assumed proxy for an acute stress
response. Belugas demonstrated no catecholamine response to the
playback of oil drilling sounds (Thomas et al., 1990) but showed a
small but statistically significant increase in catecholamines
following exposure to impulsive sounds produced from a seismic water
gun (Romano et al., 2004). A bottlenose dolphin exposed to the same
seismic water gun signals did not demonstrate a catecholamine response,
but did demonstrate a statistically significant elevation in
aldosterone (Romano et al., 2004), albeit the increase was within the
normal daily variation observed in this species (St. Aubin et al.,
1996). Increases in heart rate were observed in bottlenose dolphins to
which known calls of other dolphins were played, although no increase
in heart rate was observed when background tank noise was played back
(Miksis et al., 2001). Unfortunately, in this study, it cannot be
determined whether the increase in heart rate was due to stress or an
anticipation of being reunited with the dolphin to which the
vocalization belonged. Similarly, a young beluga's heart rate was
observed to increase during exposure to noise, with increases dependent
upon the frequency band of noise and duration of exposure, and with a
sharp decrease to normal or below normal levels upon cessation of the
exposure (Lyamin et al., 2011). Spectral analysis of heart rate
variability corroborated direct measures of heart rate (Bakhchina et
al., 2017). This response might have been in part due to the conditions
during testing, the young age of the animal, and the novelty of the
exposure; a year later the exposure was repeated at a slightly higher
received level and there was no heart rate response, indicating the
beluga whale may have acclimated to the noise exposure. Kvadsheim et
al. (2010) measured the heart rate of captive hooded seals during
exposure to sonar signals and found an increase in the heart rate of
the seals during exposure periods versus control periods when the
animals were at the surface. When the animals dove, the normal dive-
related bradycardia (decrease in heart rate) was not impacted by the
sonar exposure. Similarly, Thompson et al. (1998) observed a rapid but
short-lived decrease in heart rates in harbor and grey seals exposed to
seismic air guns (cited in Gordon et al., 2003). Williams et al. (2017)
recently monitored the heart rates of narwhals released from capture
and found that a profound dive bradycardia persisted, even though
exercise effort increased dramatically as part of their escape response
following release. Thus, although some limited evidence suggests that
tachycardia might occur as part of the acute stress response of animals
that are at the surface, the dive bradycardia persists during diving
and might be enhanced in response to an acute stressor.
Despite the limited amount of data available on sound-induced
stress responses for marine mammals exposed to anthropogenic sounds,
studies of other marine animals and terrestrial animals would also lead
us to expect that some marine mammals experience physiological stress
responses and, perhaps, physiological responses that would be
classified as ``distress'' upon exposure to high-frequency, mid-
frequency, and low-frequency sounds. For example, Jansen (1998)
reported on the relationship between acoustic exposures and
physiological responses that are indicative of stress responses in
humans (e.g., elevated respiration and increased heart rates). Jones
(1998) reported on reductions in human performance when faced with
acute, repetitive exposures to acoustic disturbance. Trimper et al.
(1998) reported on the physiological stress responses of osprey to low-
level aircraft noise while Krausman et al. (2004) reported on the
auditory and physiological stress responses of endangered Sonoran
pronghorn to military overflights. However, take due to aircraft noise
is not anticipated as a result of the Navy's activities. Smith et al.
(2004a, 2004b) identified noise-induced physiological transient stress
responses in hearing-specialist fish (i.e., goldfish) that accompanied
short- and long-term hearing losses. Welch and Welch (1970) reported
physiological and behavioral stress responses that accompanied damage
to the inner ears of fish and several mammals.
Auditory Masking
Sound can disrupt behavior through masking, or interfering with, an
animal's ability to detect, recognize, or discriminate between acoustic
signals of interest (e.g., those used for intraspecific communication
and social interactions, prey detection, predator avoidance, or
navigation) (Richardson et al., 1995; Erbe and Farmer, 2000; Tyack,
2000; Erbe et al., 2016). Masking occurs when the receipt of a sound is
interfered with by another coincident sound at similar frequencies and
at similar or higher intensity, and may occur whether the sound is
natural (e.g., snapping shrimp, wind, waves, precipitation) or
anthropogenic (e.g., shipping, sonar, seismic exploration) in origin.
As described in detail in the 2019 NWTT DSEIS/OEIS, the ability of a
noise source to mask biologically important sounds depends on the
characteristics of both the noise source and the signal of interest
(e.g., signal-to-noise ratio, temporal variability, direction), in
relation to each other and to an animal's hearing abilities (e.g.,
sensitivity, frequency range, critical ratios, frequency
discrimination, directional discrimination, age, or TTS hearing loss),
and existing ambient noise and propagation conditions. Masking these
acoustic signals can disturb the behavior of individual animals, groups
of animals, or entire populations. Masking can lead to behavioral
changes including vocal changes (e.g., Lombard effect, increasing
amplitude, or changing frequency), cessation of

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foraging, and leaving an area, to both signalers and receivers, in an
attempt to compensate for noise levels (Erbe et al., 2016).
In humans, significant masking of tonal signals occurs as a result
of exposure to noise in a narrow band of similar frequencies. As the
sound level increases, though, the detection of frequencies above those
of the masking stimulus decreases also. This principle is expected to
apply to marine mammals as well because of common biomechanical
cochlear properties across taxa.
Under certain circumstances, marine mammals experiencing
significant masking could also be impaired from maximizing their
performance fitness in survival and reproduction. Therefore, when the
coincident (masking) sound is man-made, it may be considered harassment
when disrupting or altering critical behaviors. It is important to
distinguish TTS and PTS, which persist after the sound exposure, from
masking, which only occurs during the sound exposure. Because masking
(without resulting in threshold shift) is not associated with abnormal
physiological function, it is not considered a physiological effect,
but rather a potential behavioral effect.
Richardson et al. (1995b) argued that the maximum radius of
influence of an industrial noise (including broadband low-frequency
sound transmission) on a marine mammal is the distance from the source
to the point at which the noise can barely be heard. This range is
determined by either the hearing sensitivity (including critical
ratios, or the lowest signal-to-noise ratio in which animals can detect
a signal, Finneran and Branstetter, 2013; Johnson et al., 1989;
Southall et al., 2000) of the animal or the background noise level
present. Industrial masking is most likely to affect some species'
ability to detect communication calls and natural sounds (i.e., surf
noise, prey noise, etc.; Richardson et al., 1995).
The frequency range of the potentially masking sound is important
in determining any potential behavioral impacts. For example, low-
frequency signals may have less effect on high-frequency echolocation
sounds produced by odontocetes but are more likely to affect detection
of mysticete communication calls and other potentially important
natural sounds such as those produced by surf and some prey species.
The masking of communication signals by anthropogenic noise may be
considered as a reduction in the communication space of animals (e.g.,
Clark et al., 2009; Matthews et al., 2016) and may result in energetic
or other costs as animals change their vocalization behavior (e.g.,
Miller et al., 2000; Foote et al., 2004; Parks et al., 2007; Di Iorio
and Clark, 2009; Holt et al., 2009). Masking can be reduced in
situations where the signal and noise come from different directions
(Richardson et al., 1995), through amplitude modulation of the signal,
or through other compensatory behaviors (Houser and Moore, 2014).
Masking can be tested directly in captive species (e.g., Erbe, 2008),
but in wild populations it must be either modeled or inferred from
evidence of masking compensation. There are few studies addressing
real-world masking sounds likely to be experienced by marine mammals in
the wild (e.g., Branstetter et al., 2013).
The echolocation calls of toothed whales are subject to masking by
high-frequency sound. Human data indicate low-frequency sound can mask
high-frequency sounds (i.e., upward masking). Studies on captive
odontocetes by Au et al. (1974, 1985, 1993) indicate that some species
may use various processes to reduce masking effects (e.g., adjustments
in echolocation call intensity or frequency as a function of background
noise conditions). There is also evidence that the directional hearing
abilities of odontocetes are useful in reducing masking at the high-
frequencies these cetaceans use to echolocate, but not at the low-to-
moderate frequencies they use to communicate (Zaitseva et al., 1980). A
study by Nachtigall and Supin (2008) showed that false killer whales
adjust their hearing to compensate for ambient sounds and the intensity
of returning echolocation signals.
Impacts on signal detection, measured by masked detection
thresholds, are not the only important factors to address when
considering the potential effects of masking. As marine mammals use
sound to recognize conspecifics, prey, predators, or other biologically
significant sources (Branstetter et al., 2016), it is also important to
understand the impacts of masked recognition thresholds (often called
``informational masking''). Branstetter et al., 2016 measured masked
recognition thresholds for whistle-like sounds of bottlenose dolphins
and observed that they are approximately 4 dB above detection
thresholds (energetic masking) for the same signals. Reduced ability to
recognize a conspecific call or the acoustic signature of a predator
could have severe negative impacts. Branstetter et al., 2016 observed
that if ``quality communication'' is set at 90 percent recognition the
output of communication space models (which are based on 50 percent
detection) would likely result in a significant decrease in
communication range.
As marine mammals use sound to recognize predators (Allen et al.,
2014; Cummings and Thompson, 1971; Cur[eacute] et al., 2015; Fish and
Vania, 1971), the presence of masking noise may also prevent marine
mammals from responding to acoustic cues produced by their predators,
particularly if it occurs in the same frequency band. For example,
harbor seals that reside in the coastal waters off British Columbia are
frequently targeted by mammal-eating killer whales. The seals
acoustically discriminate between the calls of mammal-eating and fish-
eating killer whales (Deecke et al., 2002), a capability that should
increase survivorship while reducing the energy required to attend to
all killer whale calls. Similarly, sperm whales (Cur[eacute] et al.,
2016; Isojunno et al., 2016), long-finned pilot whales (Visser et al.,
2016), and humpback whales (Cur[eacute] et al., 2015) changed their
behavior in response to killer whale vocalization playbacks; these
findings indicate that some recognition of predator cues could be
missed if the killer whale vocalizations were masked. The potential
effects of masked predator acoustic cues depends on the duration of the
masking noise and the likelihood of a marine mammal encountering a
predator during the time that detection and recognition of predator
cues are impeded.
Redundancy and context can also facilitate detection of weak
signals. These phenomena may help marine mammals detect weak sounds in
the presence of natural or manmade noise. Most masking studies in
marine mammals present the test signal and the masking noise from the
same direction. The dominant background noise may be highly directional
if it comes from a particular anthropogenic source such as a ship or
industrial site. Directional hearing may significantly reduce the
masking effects of these sounds by improving the effective signal-to-
noise ratio.
Masking affects both senders and receivers of acoustic signals and
can potentially have long-term chronic effects on marine mammals at the
population level as well as at the individual level. Low-frequency
ambient sound levels have increased by as much as 20 dB (more than
three times in terms of SPL) in the world's ocean from pre-industrial
periods, with most of the increase from distant commercial shipping
(Hildebrand, 2009). All anthropogenic sound sources, but especially
chronic and lower-frequency signals (e.g., from commercial vessel

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traffic), contribute to elevated ambient sound levels, thus
intensifying masking.

Impaired Communication

In addition to making it more difficult for animals to perceive and
recognize acoustic cues in their environment, anthropogenic sound
presents separate challenges for animals that are vocalizing. When they
vocalize, animals are aware of environmental conditions that affect the
``active space'' (or communication space) of their vocalizations, which
is the maximum area within which their vocalizations can be detected
before it drops to the level of ambient noise (Brenowitz, 2004; Brumm
et al., 2004; Lohr et al., 2003). Animals are also aware of
environmental conditions that affect whether listeners can discriminate
and recognize their vocalizations from other sounds, which is more
important than simply detecting that a vocalization is occurring
(Brenowitz, 1982; Brumm et al., 2004; Dooling, 2004, Marten and Marler,
1977; Patricelli et al., 2006). Most species that vocalize have evolved
with an ability to make adjustments to their vocalizations to increase
the signal-to-noise ratio, active space, and recognizability/
distinguishability of their vocalizations in the face of temporary
changes in background noise (Brumm et al., 2004; Patricelli et al.,
2006). Vocalizing animals can make adjustments to vocalization
characteristics such as the frequency structure, amplitude, temporal
structure, and temporal delivery (repetition rate), or may cease to
vocalize.
Many animals will combine several of these strategies to compensate
for high levels of background noise. Anthropogenic sounds that reduce
the signal-to-noise ratio of animal vocalizations, increase the masked
auditory thresholds of animals listening for such vocalizations, or
reduce the active space of an animal's vocalizations impair
communication between animals. Most animals that vocalize have evolved
strategies to compensate for the effects of short-term or temporary
increases in background or ambient noise on their songs or calls.
Although the fitness consequences of these vocal adjustments are not
directly known in all instances, like most other trade-offs animals
must make, some of these strategies probably come at a cost (Patricelli
et al., 2006). Shifting songs and calls to higher frequencies may also
impose energetic costs (Lambrechts, 1996). For example, in birds,
vocalizing more loudly in noisy environments may have energetic costs
that decrease the net benefits of vocal adjustment and alter a bird's
energy budget (Brumm, 2004; Wood and Yezerinac, 2006).
Marine mammals are also known to make vocal changes in response to
anthropogenic noise. In cetaceans, vocalization changes have been
reported from exposure to anthropogenic noise sources such as sonar,
vessel noise, and seismic surveying (see the following for examples:
Gordon et al., 2003; Di Iorio and Clark, 2010; Hatch et al., 2012; Holt
et al., 2008; Holt et al., 2011; Lesage et al., 1999; McDonald et al.,
2009; Parks et al., 2007, Risch et al., 2012, Rolland et al., 2012), as
well as changes in the natural acoustic environment (Dunlop et al.,
2014). Vocal changes can be temporary, or can be persistent. For
example, model simulation suggests that the increase in starting
frequency for the North Atlantic right whale upcall over the last 50
years resulted in increased detection ranges between right whales. The
frequency shift, coupled with an increase in call intensity by 20 dB,
led to a call detectability range of less than 3 km to over 9 km
(Tennessen and Parks, 2016). Holt et al. (2008) measured killer whale
call source levels and background noise levels in the one to 40 kHz
band and reported that the whales increased their call source levels by
one dB SPL for every one dB SPL increase in background noise level.
Similarly, another study on St. Lawrence River belugas reported a
similar rate of increase in vocalization activity in response to
passing vessels (Scheifele et al., 2005). Di Iorio and Clark (2010)
showed that blue whale calling rates vary in association with seismic
sparker survey activity, with whales calling more on days with surveys
than on days without surveys. They suggested that the whales called
more during seismic survey periods as a way to compensate for the
elevated noise conditions.
In some cases, these vocal changes may have fitness consequences,
such as an increase in metabolic rates and oxygen consumption, as
observed in bottlenose dolphins when increasing their call amplitude
(Holt et al., 2015). A switch from vocal communication to physical,
surface-generated sounds such as pectoral fin slapping or breaching was
observed for humpback whales in the presence of increasing natural
background noise levels, indicating that adaptations to masking may
also move beyond vocal modifications (Dunlop et al., 2010).
While these changes all represent possible tactics by the sound-
producing animal to reduce the impact of masking, the receiving animal
can also reduce masking by using active listening strategies such as
orienting to the sound source, moving to a quieter location, or
reducing self-noise from hydrodynamic flow by remaining still. The
temporal structure of noise (e.g., amplitude modulation) may also
provide a considerable release from masking through comodulation
masking release (a reduction of masking that occurs when broadband
noise, with a frequency spectrum wider than an animal's auditory filter
bandwidth at the frequency of interest, is amplitude modulated)
(Branstetter and Finneran, 2008; Branstetter et al., 2013). Signal type
(e.g., whistles, burst-pulse, sonar clicks) and spectral
characteristics (e.g., frequency modulated with harmonics) may further
influence masked detection thresholds (Branstetter et al., 2016;
Cunningham et al., 2014).

Masking Due to Sonar and Other Transducers

The functional hearing ranges of mysticetes, odontocetes, and
pinnipeds underwater overlap the frequencies of the sonar sources used
in the Navy's low-frequency active sonar (LFAS)/mid-frequency active
sonar (MFAS)/high-frequency active sonar (HFAS) training and testing
exercises. Additionally, almost all affected species' vocal repertoires
span across the frequencies of these sonar sources used by the Navy.
The closer the characteristics of the masking signal to the signal of
interest, the more likely masking is to occur. Masking by low-frequency
or mid-frequency active sonar (LFAS and MFAS) with relatively low-duty
cycles is not anticipated (or would be of very short duration) for most
cetaceans as sonar signals occur over a relatively short duration and
narrow bandwidth (overlapping with only a small portion of the hearing
range). LFAS could overlap in frequency with mysticete vocalizations,
however LFAS does not overlap with vocalizations for most marine mammal
species. For example, in the presence of LFAS, humpback whales were
observed to increase the length of their songs (Fristrup et al., 2003;
Miller et al., 2000), potentially due to the overlap in frequencies
between the whale song and the LFAS. While dolphin whistles and MFAS
are similar in frequency, masking is not anticipated (or would be of
very short duration) due to the low-duty cycle of most sonars.
As described in additional detail the 2019 NWTT DSEIS/OEIS, newer
high-duty cycle or continuous active sonars have more potential to mask
vocalizations. These sonars transmit more frequently (greater than 80
percent duty cycle) than traditional sonars, but at a substantially
lower source level. HFAS, such as pingers that operate at

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higher repetition rates (e.g., 2-10 kHz with harmonics up to 19 kHz, 76
to 77 pings per minute) (Culik et al., 2001), also operate at lower
source levels and have faster attenuation rates due to the higher
frequencies used. These lower source levels limit the range of impacts,
however compared to traditional sonar systems, individuals close to the
source are likely to experience masking at longer time scales. The
frequency range at which high-duty cycle systems operate overlaps the
vocalization frequency of many mid-frequency cetaceans. Continuous
noise at the same frequency of communicative vocalizations may cause
disruptions to communication, social interactions, acoustically
mediated cooperative behaviors, and important environmental cues. There
is also the potential for the mid-frequency sonar signals to mask
important environmental cues (e.g., predator or conspectic acoustic
cues), possibly affecting survivorship for targeted animals. While
there are currently no available studies of the impacts of high-duty
cycle sonars on marine mammals, masking due to these systems is likely
analogous to masking produced by other continuous sources (e.g., vessel
noise and low-frequency cetaceans), and would likely have similar
short-term consequences, though longer in duration due to the duration
of the masking noise. These may include changes to vocalization
amplitude and frequency (Brumm and Slabbekoorn, 2005; Hotchkin and
Parks, 2013) and behavioral impacts such as avoidance of the area and
interruptions to foraging or other essential behaviors (Gordon et al.,
2003). Long-term consequences could include changes to vocal behavior
and vocalization structure (Foote et al., 2004; Parks et al., 2007),
abandonment of habitat if masking occurs frequently enough to
significantly impair communication (Brumm and Slabbekoorn, 2005), a
potential decrease in survivorship if predator vocalizations are masked
(Brumm and Slabbekoorn, 2005), and a potential decrease in recruitment
if masking interferes with reproductive activities or mother-calf
communication (Gordon et al., 2003).

Masking Due to Vessel Noise

Masking is more likely to occur in the presence of broadband,
relatively continuous noise sources such as vessels. Several studies
have shown decreases in marine mammal communication space and changes
in behavior as a result of the presence of vessel noise. For example,
right whales were observed to shift the frequency content of their
calls upward while reducing the rate of calling in areas of increased
anthropogenic noise (Parks et al., 2007) as well as increasing the
amplitude (intensity) of their calls (Parks, 2009; Parks et al., 2011).
Fournet et al. (2018) observed that humpback whales in Alaska responded
to increasing ambient sound levels (natural and anthropogenic) by
increasing the source levels of their calls (non-song vocalizations).
Clark et al. (2009) also observed that right whales communication space
decreased by up to 84 percent in the presence of vessels (Clark et al.,
2009). Cholewiak et al. (2018) also observed loss in communication
space in Stellwagen National Marine Sanctuary for North Atlantic right
whales, fin whales, and humpback whales with increased ambient noise
and shipping noise. Gabriele et al. (2018) modeled the effects of
vessel traffic sound on communication space in Glacier Bay National
Park in Alaska and found that typical summer vessel traffic in the Park
causes losses of communication space to singing whales (reduced by 13-
28 percent), calling whales (18-51 percent), and roaring seals (32-61
percent), particularly during daylight hours and even in the absence of
cruise ships. Dunlop (2019) observed that an increase in vessel noise
reduced modelled communication space and resulted in significant
reduction in group social interactions in Australian humpback whales.
However, communication signal masking did not fully explain this change
in social behavior in the model, indicating there may also be an
additional effect of the physical presence of the vessel on social
behavior (Dunlop, 2019). Although humpback whales off Australia did not
change the frequency or duration of their vocalizations in the presence
of ship noise, their source levels were lower than expected based on
source level changes to wind noise, potentially indicating some signal
masking (Dunlop, 2016). Multiple delphinid species have also been shown
to increase the minimum or maximum frequencies of their whistles in the
presence of anthropogenic noise and reduced communication space (for
examples see: Holt et al., 2008; Holt et al., 2011; Gervaise et al.,
2012; Williams et al., 2013; Hermannsen et al., 2014; Papale et al.,
2015; Liu et al., 2017).

Behavioral Response/Disturbance

Behavioral responses to sound are highly variable and context-
specific. Many different variables can influence an animal's perception
of and response to (nature and magnitude) an acoustic event. An
animal's prior experience with a sound or sound source affects whether
it is less likely (habituation) or more likely (sensitization) to
respond to certain sounds in the future (animals can also be innately
predisposed to respond to certain sounds in certain ways) (Southall et
al., 2007). Related to the sound itself, the perceived nearness of the
sound, bearing of the sound (approaching vs. retreating), the
similarity of a sound to biologically relevant sounds in the animal's
environment (i.e., calls of predators, prey, or conspecifics), and
familiarity of the sound may affect the way an animal responds to the
sound (Southall et al., 2007, DeRuiter et al., 2013). Individuals (of
different age, gender, reproductive status, etc.) among most
populations will have variable hearing capabilities, and differing
behavioral sensitivities to sounds that will be affected by prior
conditioning, experience, and current activities of those individuals.
Often, specific acoustic features of the sound and contextual variables
(i.e., proximity, duration, or recurrence of the sound or the current
behavior that the marine mammal is engaged in or its prior experience),
as well as entirely separate factors such as the physical presence of a
nearby vessel, may be more relevant to the animal's response than the
received level alone. For example, Goldbogen et al. (2013) demonstrated
that individual behavioral state was critically important in
determining response of blue whales to sonar, noting that some
individuals engaged in deep (>50 m) feeding behavior had greater dive
responses than those in shallow feeding or non-feeding conditions. Some
blue whales in the Goldbogen et al. (2013) study that were engaged in
shallow feeding behavior demonstrated no clear changes in diving or
movement even when received levels (RLs) were high (~160 dB re:
1[mu]Pa) for exposures to 3-4 kHz sonar signals, while others showed a
clear response at exposures at lower received levels of sonar and
pseudorandom noise.
Studies by DeRuiter et al. (2012) indicate that variability of
responses to acoustic stimuli depends not only on the species receiving
the sound and the sound source, but also on the social, behavioral, or
environmental contexts of exposure. Another study by DeRuiter et al.
(2013) examined behavioral responses of Cuvier's beaked whales to MF
sonar and found that whales responded strongly at low received levels
(RL of 89-127 dB re: 1[mu]Pa) by ceasing normal fluking and
echolocation, swimming rapidly away, and extending both dive duration
and subsequent non-foraging intervals when

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the sound source was 3.4-9.5 km away. Importantly, this study also
showed that whales exposed to a similar range of received levels (78-
106 dB re: 1 [mu]Pa) from distant sonar exercises (118 km away) did not
elicit such responses, suggesting that context may moderate reactions.
Ellison et al. (2012) outlined an approach to assessing the effects
of sound on marine mammals that incorporates contextual-based factors.
The authors recommend considering not just the received level of sound,
but also the activity the animal is engaged in at the time the sound is
received, the nature and novelty of the sound (i.e., is this a new
sound from the animal's perspective), and the distance between the
sound source and the animal. They submit that this ``exposure
context,'' as described, greatly influences the type of behavioral
response exhibited by the animal. Forney et al. (2017) also point out
that an apparent lack of response (e.g., no displacement or avoidance
of a sound source) may not necessarily mean there is no cost to the
individual or population, as some resources or habitats may be of such
high value that animals may choose to stay, even when experiencing
stress or hearing loss. Forney et al. (2017) recommend considering both
the costs of remaining in an area of noise exposure such as TTS, PTS,
or masking, which could lead to an increased risk of predation or other
threats or a decreased capability to forage, and the costs of
displacement, including potential increased risk of vessel strike,
increased risks of predation or competition for resources, or decreased
habitat suitable for foraging, resting, or socializing. This sort of
contextual information is challenging to predict with accuracy for
ongoing activities that occur over large spatial and temporal expanses.
However, distance is one contextual factor for which data exist to
quantitatively inform a take estimate, and the method for predicting
Level B harassment in this rule does consider distance to the source.
Other factors are often considered qualitatively in the analysis of the
likely consequences of sound exposure, where supporting information is
available.
Friedlaender et al. (2016) provided the first integration of direct
measures of prey distribution and density variables incorporated into
across-individual analyses of behavior responses of blue whales to
sonar, and demonstrated a five-fold increase in the ability to quantify
variability in blue whale diving behavior. These results illustrate
that responses evaluated without such measurements for foraging animals
may be misleading, which again illustrates the context-dependent nature
of the probability of response.
Exposure of marine mammals to sound sources can result in, but is
not limited to, no response or any of the following observable
responses: Increased alertness; orientation or attraction to a sound
source; vocal modifications; cessation of feeding; cessation of social
interaction; alteration of movement or diving behavior; habitat
abandonment (temporary or permanent); and, in severe cases, panic,
flight, stampede, or stranding, potentially resulting in death
(Southall et al., 2007). A review of marine mammal responses to
anthropogenic sound was first conducted by Richardson (1995). More
recent reviews (Nowacek et al., 2007; DeRuiter et al., 2012 and 2013;
Ellison et al., 2012; Gomez et al., 2016) address studies conducted
since 1995 and focused on observations where the received sound level
of the exposed marine mammal(s) was known or could be estimated. Gomez
et al. (2016) conducted a review of the literature considering the
contextual information of exposure in addition to received level and
found that higher received levels were not always associated with more
severe behavioral responses and vice versa. Southall et al. (2016)
states that results demonstrate that some individuals of different
species display clear yet varied responses, some of which have negative
implications, while others appear to tolerate high levels, and that
responses may not be fully predictable with simple acoustic exposure
metrics (e.g., received sound level). Rather, the authors state that
differences among species and individuals along with contextual aspects
of exposure (e.g., behavioral state) appear to affect response
probability. The following subsections provide examples of behavioral
responses that provide an idea of the variability in behavioral
responses that would be expected given the differential sensitivities
of marine mammal species to sound and the wide range of potential
acoustic sources to which a marine mammal may be exposed. Behavioral
responses that could occur for a given sound exposure should be
determined from the literature that is available for each species, or
extrapolated from closely related species when no information exists,
along with contextual factors.
Flight Response
A flight response is a dramatic change in normal movement to a
directed and rapid movement away from the perceived location of a sound
source. The flight response differs from other avoidance responses in
the intensity of the response (e.g., directed movement, rate of
travel). Relatively little information on flight responses of marine
mammals to anthropogenic signals exist, although observations of flight
responses to the presence of predators have occurred (Connor and
Heithaus, 1996). The result of a flight response could range from
brief, temporary exertion and displacement from the area where the
signal provokes flight to, in extreme cases, being a component of
marine mammal strandings associated with sonar activities (Evans and
England, 2001). If marine mammals respond to Navy vessels that are
transmitting active sonar in the same way that they might respond to a
predator, their probability of flight responses should increase when
they perceive that Navy vessels are approaching them directly, because
a direct approach may convey detection and intent to capture (Burger
and Gochfeld, 1981, 1990; Cooper, 1997, 1998). There are limited data
on flight response for marine mammals in water; however, there are
examples of this response in species on land. For instance, the
probability of flight responses in Dall's sheep Ovis dalli dalli (Frid,
2001), hauled-out ringed seals Phoca hispida (Born et al., 1999),
Pacific brant (Branta bernicl nigricans), and Canada geese (B.
canadensis) increased as a helicopter or fixed-wing aircraft more
directly approached groups of these animals (Ward et al., 1999). Bald
eagles (Haliaeetus leucocephalus) perched on trees alongside a river
were also more likely to flee from a paddle raft when their perches
were closer to the river or were closer to the ground (Steidl and
Anthony, 1996).
Response to Predator
As discussed earlier, evidence suggests that at least some marine
mammals have the ability to acoustically identify potential predators.
For example, harbor seals that reside in the coastal waters off British
Columbia are frequently targeted by certain groups of killer whales,
but not others. The seals discriminate between the calls of threatening
and non-threatening killer whales (Deecke et al., 2002), a capability
that should increase survivorship while reducing the energy required
for attending to and responding to all killer whale calls. The
occurrence of masking or hearing impairment provides a means by which
marine mammals may be prevented from responding to the acoustic cues
produced by their predators. Whether or not this is a

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possibility depends on the duration of the masking/hearing impairment
and the likelihood of encountering a predator during the time that
predator cues are impeded.
Alteration of Diving or Movement
Changes in dive behavior can vary widely. They may consist of
increased or decreased dive times and surface intervals as well as
changes in the rates of ascent and descent during a dive (e.g., Frankel
and Clark, 2000; Ng and Leung, 2003; Nowacek et al.; 2004; Goldbogen et
al., 2013a, 2013b). Variations in dive behavior may reflect
interruptions in biologically significant activities (e.g., foraging)
or they may be of little biological significance. Variations in dive
behavior may also expose an animal to potentially harmful conditions
(e.g., increasing the chance of ship-strike) or may serve as an
avoidance response that enhances survivorship. The impact of a
variation in diving resulting from an acoustic exposure depends on what
the animal is doing at the time of the exposure and the type and
magnitude of the response.
Nowacek et al. (2004) reported disruptions of dive behaviors in
foraging North Atlantic right whales when exposed to an alerting
stimulus, an action, they noted, that could lead to an increased
likelihood of ship strike. However, the whales did not respond to
playbacks of either right whale social sounds or vessel noise,
highlighting the importance of the sound characteristics in producing a
behavioral reaction. Conversely, Indo-Pacific humpback dolphins have
been observed to dive for longer periods of time in areas where vessels
were present and/or approaching (Ng and Leung, 2003). In both of these
studies, the influence of the sound exposure cannot be decoupled from
the physical presence of a surface vessel, thus complicating
interpretations of the relative contribution of each stimulus to the
response. Indeed, the presence of surface vessels, their approach, and
speed of approach, seemed to be significant factors in the response of
the Indo-Pacific humpback dolphins (Ng and Leung, 2003). Low-frequency
signals of the Acoustic Thermometry of Ocean Climate (ATOC) sound
source were not found to affect dive times of humpback whales in
Hawaiian waters (Frankel and Clark, 2000) or to overtly affect elephant
seal dives (Costa et al., 2003). They did, however, produce subtle
effects that varied in direction and degree among the individual seals,
illustrating the equivocal nature of behavioral effects and consequent
difficulty in defining and predicting them. Lastly, as noted
previously, DeRuiter et al. (2013) noted that distance from a sound
source may moderate marine mammal reactions in their study of Cuvier's
beaked whales, which showed the whales swimming rapidly and silently
away when a sonar signal was 3.4-9.5 km away while showing no such
reaction to the same signal when the signal was 118 km away even though
the received levels were similar.
Foraging
Disruption of feeding behavior can be difficult to correlate with
anthropogenic sound exposure, so it is usually inferred by observed
displacement from known foraging areas, the appearance of secondary
indicators (e.g., bubble nets or sediment plumes), or changes in dive
behavior. As for other types of behavioral response, the frequency,
duration, and temporal pattern of signal presentation, as well as
differences in species sensitivity, are likely contributing factors to
differences in response in any given circumstance (e.g., Croll et al.,
2001; Harris et al., 2017; Madsen et al., 2006a; Nowacek et al.; 2004;
Yazvenko et al., 2007). A determination of whether foraging disruptions
incur fitness consequences would require information on or estimates of
the energetic requirements of the affected individuals and the
relationship between prey availability, foraging effort and success,
and the life history stage of the animal.
Noise from seismic surveys was not found to impact the feeding
behavior in western grey whales off the coast of Russia (Yazvenko et
al., 2007). Visual tracking, passive acoustic monitoring, and movement
recording tags were used to quantify sperm whale behavior prior to,
during, and following exposure to air gun arrays at received levels in
the range 140-160 dB at distances of 7-13 km, following a phase-in of
sound intensity and full array exposures at 1-13 km (Madsen et al.,
2006a; Miller et al., 2009). Sperm whales did not exhibit horizontal
avoidance behavior at the surface. However, foraging behavior may have
been affected. The sperm whales exhibited 19 percent less vocal (buzz)
rate during full exposure relative to post exposure, and the whale that
was approached most closely had an extended resting period and did not
resume foraging until the air guns had ceased firing. The remaining
whales continued to execute foraging dives throughout exposure;
however, swimming movements during foraging dives were six percent
lower during exposure than control periods (Miller et al., 2009). These
data raise concerns that air gun surveys may impact foraging behavior
in sperm whales, although more data are required to understand whether
the differences were due to exposure or natural variation in sperm
whale behavior (Miller et al., 2009).
Balaenopterid whales exposed to moderate low-frequency signals
similar to the ATOC sound source demonstrated no variation in foraging
activity (Croll et al., 2001), whereas five out of six North Atlantic
right whales exposed to an acoustic alarm interrupted their foraging
dives (Nowacek et al., 2004). Although the received SPLs were similar
in the latter two studies, the frequency, duration, and temporal
pattern of signal presentation were different. These factors, as well
as differences in species sensitivity, are likely contributing factors
to the differential response. Blue whales exposed to mid-frequency
sonar in the Southern California Bight were less likely to produce low
frequency calls usually associated with feeding behavior (Melc[oacute]n
et al., 2012). However, Melc[oacute]n et al. (2012) were unable to
determine if suppression of low frequency calls reflected a change in
their feeding performance or abandonment of foraging behavior and
indicated that implications of the documented responses are unknown.
Further, it is not known whether the lower rates of calling actually
indicated a reduction in feeding behavior or social contact since the
study used data from remotely deployed, passive acoustic monitoring
buoys. In contrast, blue whales increased their likelihood of calling
when ship noise was present, and decreased their likelihood of calling
in the presence of explosive noise, although this result was not
statistically significant (Melc[oacute]n et al., 2012). Additionally,
the likelihood of an animal calling decreased with the increased
received level of mid-frequency sonar, beginning at a SPL of
approximately 110-120 dB re: 1 [mu]Pa (Melc[oacute]n et al., 2012).
Results from behavioral response studies in Southern California waters
indicated that, in some cases and at low received levels, tagged blue
whales responded to mid-frequency sonar but that those responses were
were generally brief, of low to moderate severity, and highly dependent
on exposure context (Southall et al., 2011; Southall et al., 2012b,
Southall et al., 2019b). Information on or estimates of the energetic
requirements of the individuals and the relationship between prey
availability, foraging effort and success, and the life history stage
of the animal will help better inform a

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determination of whether foraging disruptions incur fitness
consequences. Surface feeding blue whales did not show a change in
behavior in response to mid-frequency simulated and real sonar sources
with received levels between 90 and 179 dB re: 1 [mu]Pa, but deep
feeding and non-feeding whales showed temporary reactions including
cessation of feeding, reduced initiation of deep foraging dives,
generalized avoidance responses, and changes to dive behavior. The
behavioral responses they observed were generally brief, of low to
moderate severity, and highly dependent on exposure context (behavioral
state, source-to-whale horizontal range, and prey availability)
(DeRuiter et al., 2017; Goldbogen et al., 2013b; Sivle et al., 2015).
Goldbogen et al. (2013b) indicate that disruption of feeding and
displacement could impact individual fitness and health. However, for
this to be true, we would have to assume that an individual whale could
not compensate for this lost feeding opportunity by either immediately
feeding at another location, by feeding shortly after cessation of
acoustic exposure, or by feeding at a later time. There is no
indication this is the case, particularly since unconsumed prey would
likely still be available in the environment in most cases following
the cessation of acoustic exposure.
Similarly, while the rates of foraging lunges decrease in humpback
whales due to sonar exposure, there was variability in the response
across individuals, with one animal ceasing to forage completely and
another animal starting to forage during the exposure (Sivle et al.,
2016). In addition, almost half of the animals that exhibited avoidance
behavior were foraging before the exposure but the others were not; the
animals that exhibited avoidance behavior while not feeding responded
at a slightly lower received level and greater distance than those that
were feeding (Wensveen et al., 2017). These findings indicate that the
behavioral state of the animal plays a role in the type and severity of
a behavioral response. In fact, when the prey field was mapped and used
as a covariate in similar models looking for a response in the same
blue whales, the response in deep-feeding behavior by blue whales was
even more apparent, reinforcing the need for contextual variables to be
included when assessing behavioral responses (Friedlaender et al.,
2016).
Breathing
Respiration naturally varies with different behaviors and
variations in respiration rate as a function of acoustic exposure can
be expected to co-occur with other behavioral reactions, such as a
flight response or an alteration in diving. However, respiration rates
in and of themselves may be representative of annoyance or an acute
stress response. Mean exhalation rates of gray whales at rest and while
diving were found to be unaffected by seismic surveys conducted
adjacent to the whale feeding grounds (Gailey et al., 2007). Studies
with captive harbor porpoises showed increased respiration rates upon
introduction of acoustic alarms (Kastelein et al., 2001; Kastelein et
al., 2006a) and emissions for underwater data transmission (Kastelein
et al., 2005). However, exposure of the same acoustic alarm to a
striped dolphin under the same conditions did not elicit a response
(Kastelein et al., 2006a), again highlighting the importance in
understanding species differences in the tolerance of underwater noise
when determining the potential for impacts resulting from anthropogenic
sound exposure.
Social Relationships
Social interactions between mammals can be affected by noise via
the disruption of communication signals or by the displacement of
individuals. Disruption of social relationships therefore depends on
the disruption of other behaviors (e.g., avoidance, masking, etc.).
Sperm whales responded to military sonar, apparently from a submarine,
by dispersing from social aggregations, moving away from the sound
source, remaining relatively silent, and becoming difficult to approach
(Watkins et al., 1985). In contrast, sperm whales in the Mediterranean
that were exposed to submarine sonar continued calling (J. Gordon pers.
comm. cited in Richardson et al., 1995). Long-finned pilot whales
exposed to three types of disturbance--playbacks of killer whale
sounds, naval sonar exposure, and tagging--resulted in increased group
sizes (Visser et al., 2016). In response to sonar, pilot whales also
spent more time at the surface with other members of the group (Visser
et al., 2016). However, social disruptions must be considered in
context of the relationships that are affected. While some disruptions
may not have deleterious effects, others, such as long-term or repeated
disruptions of mother/calf pairs or interruption of mating behaviors,
have the potential to affect the growth and survival or reproductive
effort/success of individuals.
Vocalizations (Also See Auditory Masking Section)
Vocal changes in response to anthropogenic noise can occur across
the repertoire of sound production modes used by marine mammals, such
as whistling, echolocation click production, calling, and singing.
Changes in vocalization behavior that may result in response to
anthropogenic noise can occur for any of these modes and may result
from a need to compete with an increase in background noise or may
reflect an increased vigilance or a startle response. For example, in
the presence of potentially masking signals (low-frequency active
sonar), humpback whales have been observed to increase the length of
their songs (Miller et al., 2000; Fristrup et al., 2003). A similar
compensatory effect for the presence of low-frequency vessel noise has
been suggested for right whales; right whales have been observed to
shift the frequency content of their calls upward while reducing the
rate of calling in areas of increased anthropogenic noise (Parks et
al., 2007; Roland et al., 2012). Killer whales off the northwestern
coast of the United States have been observed to increase the duration
of primary calls once a threshold in observing vessel density (e.g.,
whale watching) was reached, which has been suggested as a response to
increased masking noise produced by the vessels (Foote et al., 2004;
NOAA, 2014b). In contrast, both sperm and pilot whales potentially
ceased sound production during the Heard Island feasibility test
(Bowles et al., 1994), although it cannot be absolutely determined
whether the inability to acoustically detect the animals was due to the
cessation of sound production or the displacement of animals from the
area.
Cerchio et al. (2014) used passive acoustic monitoring to document
the presence of singing humpback whales off the coast of northern
Angola and to opportunistically test for the effect of seismic survey
activity on the number of singing whales. Two recording units were
deployed between March and December 2008 in the offshore environment;
numbers of singers were counted every hour. Generalized Additive Mixed
Models were used to assess the effect of survey day (seasonality), hour
(diel variation), moon phase, and received levels of noise (measured
from a single pulse during each ten-minute sampled period) on singer
number. The number of singers significantly decreased with increasing
received level of noise, suggesting that humpback whale communication
was disrupted to some extent by the survey activity.
Castellote et al. (2012) reported acoustic and behavioral changes
by fin whales in response to shipping and air gun noise. Acoustic
features of fin

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whale song notes recorded in the Mediterranean Sea and northeast
Atlantic Ocean were compared for areas with different shipping noise
levels and traffic intensities and during an air gun survey. During the
first 72 hours of the survey, a steady decrease in song received levels
and bearings to singers indicated that whales moved away from the
acoustic source and out of a Navy study area. This displacement
persisted for a time period well beyond the 10-day duration of air gun
activity, providing evidence that fin whales may avoid an area for an
extended period in the presence of increased noise. The authors
hypothesize that fin whale acoustic communication is modified to
compensate for increased background noise and that a sensitization
process may play a role in the observed temporary displacement.
Seismic pulses at average received levels of 131 dB re: 1
micropascal squared per second ([mu]Pa2-s) caused blue whales to
increase call production (Di Iorio and Clark, 2010). In contrast,
McDonald et al. (1995) tracked a blue whale with seafloor seismometers
and reported that it stopped vocalizing and changed its travel
direction at a range of 10 km from the seismic vessel (estimated
received level 143 dB re: 1 [mu]Pa peak-to-peak). Blackwell et al.
(2013) found that bowhead whale call rates dropped significantly at
onset of air gun use at sites with a median distance of 41-45 km from
the survey. Blackwell et al. (2015) expanded this analysis to show that
whales actually increased calling rates as soon as air gun signals were
detectable before ultimately decreasing calling rates at higher
received levels (i.e., 10-minute cumulative sound exposure level (cSEL)
of ~127 dB). Overall, these results suggest that bowhead whales may
adjust their vocal output in an effort to compensate for noise before
ceasing vocalization effort and ultimately deflecting from the acoustic
source (Blackwell et al., 2013, 2015). Captive bottlenose dolphins
sometimes vocalized after an exposure to impulse sound from a seismic
water gun (Finneran et al., 2010a). These studies demonstrate that even
low levels of noise received far from the noise source can induce
changes in vocalization and/or behavioral responses.
Avoidance
Avoidance is the displacement of an individual from an area or
migration path as a result of the presence of a sound or other
stressors. Richardson et al. (1995) noted that avoidance reactions are
the most obvious manifestations of disturbance in marine mammals.
Avoidance is qualitatively different from the flight response, but also
differs in the magnitude of the response (i.e., directed movement, rate
of travel, etc.). Oftentimes avoidance is temporary, and animals return
to the area once the noise has ceased. Acute avoidance responses have
been observed in captive porpoises and pinnipeds exposed to a number of
different sound sources (Kastelein et al., 2001; Finneran et al., 2003;
Kastelein et al., 2006a; Kastelein et al., 2006b). Short-term avoidance
of seismic surveys, low frequency emissions, and acoustic deterrents
have also been noted in wild populations of odontocetes (Bowles et al.,
1994; Goold, 1996; 1998; Stone et al., 2000; Morton and Symonds, 2002)
and to some extent in mysticetes (Gailey et al., 2007). Longer-term
displacement is possible, however, which may lead to changes in
abundance or distribution patterns of the affected species in the
affected region if habituation to the presence of the sound does not
occur (e.g., Blackwell et al., 2004; Bejder et al., 2006; Teilmann et
al., 2006). Longer term or repetitive/chronic displacement for some
dolphin groups and for manatees has been suggested to be due to the
presence of chronic vessel noise (Haviland-Howell et al., 2007; Miksis-
Olds et al., 2007). Gray whales have been reported deflecting from
customary migratory paths in order to avoid noise from air gun surveys
(Malme et al., 1984). Humpback whales showed avoidance behavior in the
presence of an active air gun array during observational studies and
controlled exposure experiments in western Australia (McCauley et al.,
2000a).
As discussed earlier, Forney et al. (2017) detailed the potential
effects of noise on marine mammal populations with high site fidelity,
including displacement and auditory masking, noting that a lack of
observed response does not imply absence of fitness costs and that
apparent tolerance of disturbance may have population-level impacts
that are less obvious and difficult to document. Avoidance of overlap
between disturbing noise and areas and/or times of particular
importance for sensitive species may be critical to avoiding
population-level impacts because (particularly for animals with high
site fidelity) there may be a strong motivation to remain in the area
despite negative impacts. Forney et al. (2017) stated that, for these
animals, remaining in a disturbed area may reflect a lack of
alternatives rather than a lack of effects. The authors discuss several
case studies, including western Pacific gray whales, which are a small
population of mysticetes believed to be adversely affected by oil and
gas development off Sakhalin Island, Russia (Weller et al., 2002;
Reeves et al., 2005). Western gray whales display a high degree of
interannual site fidelity to the area for foraging purposes, and
observations in the area during air gun surveys have shown the
potential for harm caused by displacement from such an important area
(Weller et al., 2006; Johnson et al., 2007). Forney et al. (2017) also
discuss beaked whales, noting that anthropogenic effects in areas where
they are resident could cause severe biological consequences, in part
because displacement may adversely affect foraging rates, reproduction,
or health, while an overriding instinct to remain could lead to more
severe acute effects.
In 1998, the Navy conducted a Low Frequency Sonar Scientific
Research Program (LFS SRP) specifically to study behavioral responses
of several species of marine mammals to exposure to LF sound, including
one phase that focused on the behavior of gray whales to low frequency
sound signals. The objective of this phase of the LFS SRP was to
determine whether migrating gray whales respond more strongly to
received levels, sound gradient, or distance from the source, and to
compare whale avoidance responses to an LF source in the center of the
migration corridor versus in the offshore portion of the migration
corridor. A single source was used to broadcast LFAS sounds at received
levels of 170-178 dB re: 1 [mu]Pa. The Navy reported that the whales
showed some avoidance responses when the source was moored one mile
(1.8 km) offshore, and located within the migration path, but the
whales returned to their migration path when they were a few kilometers
beyond the source. When the source was moored two miles (3.7 km)
offshore, responses were much less, even when the source level was
increased to achieve the same received levels in the middle of the
migration corridor as whales received when the source was located
within the migration corridor (Clark et al., 1999). In addition, the
researchers noted that the offshore whales did not seem to avoid the
louder offshore source.
Also during the LFS SRP, researchers sighted numerous odontocete
and pinniped species in the vicinity of the sound exposure tests with
LFA sonar. The MF and HF hearing specialists present in California and
Hawaii showed no immediately obvious responses or changes in sighting
rates as a function of source conditions. Consequently, the researchers

[[Page 33948]]

concluded that none of these species had any obvious behavioral
reaction to LFA sonar signals at received levels similar to those that
produced only minor short-term behavioral responses in the baleen
whales (i.e., LF hearing specialists). Thus, for odontocetes, the
chances of injury and/or significant behavioral responses to LFA sonar
would be low given the MF/HF specialists' observed lack of response to
LFA sounds during the LFS SRP and due to the MF/HF frequencies to which
these animals are adapted to hear (Clark and Southall, 2009).
Maybaum (1993) conducted sound playback experiments to assess the
effects of MFAS on humpback whales in Hawaiian waters. Specifically,
she exposed focal pods to sounds of a 3.3-kHz sonar pulse, a sonar
frequency sweep from 3.1 to 3.6 kHz, and a control (blank) tape while
monitoring behavior, movement, and underwater vocalizations. The two
types of sonar signals differed in their effects on the humpback
whales, but both resulted in avoidance behavior. The whales responded
to the pulse by increasing their distance from the sound source and
responded to the frequency sweep by increasing their swimming speeds
and track linearity. In the Caribbean, sperm whales avoided exposure to
mid-frequency submarine sonar pulses, in the range of 1,000 Hz to
10,000 Hz (IWC, 2005).
Kvadsheim et al. (2007) conducted a controlled exposure experiment
in which killer whales fitted with D-tags were exposed to mid-frequency
active sonar (Source A: A 1.0 second upsweep 209 dB at 1-2 kHz every 10
seconds for 10 minutes; Source B: with a 1.0 second upsweep 197 dB at
6-7 kHz every 10 seconds for 10 minutes). When exposed to Source A, a
tagged whale and the group it was traveling with did not appear to
avoid the source. When exposed to Source B, the tagged whales along
with other whales that had been carousel feeding, where killer whales
cooperatively herd fish schools into a tight ball towards the surface
and feed on the fish which have been stunned by tailslaps, and
subsurface feeding (Simila, 1997) ceased feeding during the approach of
the sonar and moved rapidly away from the source. When exposed to
Source B, Kvadsheim et al. (2007) reported that a tagged killer whale
seemed to try to avoid further exposure to the sound field by the
following behaviors: Immediately swimming away (horizontally) from the
source of the sound; engaging in a series of erratic and frequently
deep dives that seemed to take it below the sound field; or swimming
away while engaged in a series of erratic and frequently deep dives.
Although the sample sizes in this study are too small to support
statistical analysis, the behavioral responses of the killer whales
were consistent with the results of other studies.
Southall et al. (2007) reviewed the available literature on marine
mammal hearing and physiological and behavioral responses to human-made
sound with the goal of proposing exposure criteria for certain effects.
This peer-reviewed compilation of literature is very valuable, though
Southall et al. (2007) note that not all data are equal and some have
poor statistical power, insufficient controls, and/or limited
information on received levels, background noise, and other potentially
important contextual variables. Such data were reviewed and sometimes
used for qualitative illustration, but no quantitative criteria were
recommended for behavioral responses. All of the studies considered,
however, contain an estimate of the received sound level when the
animal exhibited the indicated response.
In the Southall et al. (2007) publication, for the purposes of
analyzing responses of marine mammals to anthropogenic sound and
developing criteria, the authors differentiate between single pulse
sounds, multiple pulse sounds, and non-pulse sounds. LFAS/MFAS/HFAS are
considered non-pulse sounds. Southall et al. (2007) summarize the
studies associated with low-frequency, mid-frequency, and high-
frequency cetacean and pinniped responses to non-pulse sounds, based
strictly on received level, in Appendix C of their article (referenced
and summarized in the following paragraphs).
The studies that address responses of low-frequency cetaceans to
non-pulse sounds include data gathered in the field and related to
several types of sound sources (of varying similarity to active sonar)
including: Vessel noise, drilling and machinery playback, low-frequency
M-sequences (sine wave with multiple phase reversals) playback,
tactical low-frequency active sonar playback, drill ships, ATOC source,
and non-pulse playbacks. These studies generally indicate no (or very
limited) responses to received levels in the 90 to 120 dB re: 1 [mu]Pa
range and an increasing likelihood of avoidance and other behavioral
effects in the 120 to 160 dB re: 1 [mu]Pa range. As mentioned earlier,
though, contextual variables play a very important role in the reported
responses and the severity of effects are not linear when compared to
received level. Also, few of the laboratory or field datasets had
common conditions, behavioral contexts, or sound sources, so it is not
surprising that responses differ.
The studies that address responses of mid-frequency cetaceans to
non-pulse sounds include data gathered both in the field and the
laboratory and related to several different sound sources (of varying
similarity to active sonar) including: Pingers, drilling playbacks,
ship and ice-breaking noise, vessel noise, Acoustic Harassment Devices
(AHDs), Acoustic Deterrent Devices (ADDs), MFAS, and non-pulse bands
and tones. Southall et al. (2007) were unable to come to a clear
conclusion regarding the results of these studies. In some cases,
animals in the field showed significant responses to received levels
between 90 and 120 dB re: 1 [mu]Pa, while in other cases these
responses were not seen in the 120 to 150 dB re: 1 [mu]Pa range. The
disparity in results was likely due to contextual variation and the
differences between the results in the field and laboratory data
(animals typically responded at lower levels in the field).
The studies that address responses of high-frequency cetaceans to
non-pulse sounds include data gathered both in the field and the
laboratory and related to several different sound sources (of varying
similarity to active sonar) including: Pingers, AHDs, and various
laboratory non-pulse sounds. All of these data were collected from
harbor porpoises. Southall et al. (2007) concluded that the existing
data indicate that harbor porpoises are likely sensitive to a wide
range of anthropogenic sounds at low received levels (~90 to 120 dB re:
1 [mu]Pa), at least for initial exposures. All recorded exposures above
140 dB re: 1 [mu]Pa induced profound and sustained avoidance behavior
in wild harbor porpoises (Southall et al., 2007). Rapid habituation was
noted in some but not all studies. There are no data to indicate
whether other high frequency cetaceans are as sensitive to
anthropogenic sound as harbor porpoises.
The studies that address the responses of pinnipeds in water to
non-impulsive sounds include data gathered both in the field and the
laboratory and related to several different sound sources including:
AHDs, ATOC, various non-pulse sounds used in underwater data
communication, underwater drilling, and construction noise. Few studies
existed with enough information to include them in the analysis. The
limited data suggested that exposures to non-pulse sounds between 90
and 140 dB re: 1 [mu]Pa generally do not result in strong behavioral
responses in pinnipeds in water, but no data exist at higher received
levels.

[[Page 33949]]

In 2007, the first in a series of behavioral response studies (BRS)
on deep diving odontocetes conducted by NMFS, Navy, and other
scientists showed one Blainville's beaked whale responding to an MFAS
playback. Tyack et al. (2011) indicates that the playback began when
the tagged beaked whale was vocalizing at depth (at the deepest part of
a typical feeding dive), following a previous control with no sound
exposure. The whale appeared to stop clicking significantly earlier
than usual, when exposed to MF signals in the 130-140 dB (rms) received
level range. After a few more minutes of the playback, when the
received level reached a maximum of 140-150 dB, the whale ascended on
the slow side of normal ascent rates with a longer than normal ascent,
at which point the exposure was terminated. The results are from a
single experiment and a greater sample size is needed before robust and
definitive conclusions can be drawn. Tyack et al. (2011) also indicates
that Blainville's beaked whales appear to be sensitive to noise at
levels well below expected TTS (~160 dB re: 1[mu] Pa). This sensitivity
was manifested by an adaptive movement away from a sound source. This
response was observed irrespective of whether the signal transmitted
was within the band width of MFAS, which suggests that beaked whales
may not respond to the specific sound signatures. Instead, they may be
sensitive to any pulsed sound from a point source in this frequency
range of the MFAS transmission. The response to such stimuli appears to
involve the beaked whale increasing the distance between it and the
sound source. Overall the results from the 2007-2008 study showed a
change in diving behavior of the Blainville's beaked whale to playback
of MFAS and predator sounds (Boyd et al., 2008; Southall et al., 2009;
Tyack et al., 2011).
Stimpert et al. (2014) tagged a Baird's beaked whale, which was
subsequently exposed to simulated MFAS. Received levels of sonar on the
tag increased to a maximum of 138 dB re: 1 [mu]Pa, which occurred
during the first exposure dive. Some sonar received levels could not be
measured due to flow noise and surface noise on the tag.
Reaction to mid-frequency sounds included premature cessation of
clicking and termination of a foraging dive, and a slower ascent rate
to the surface. Results from a similar behavioral response study in
southern California waters were presented for the 2010-2011 field
season (Southall et al., 2011; DeRuiter et al., 2013b). DeRuiter et al.
(2013b) presented results from two Cuvier's beaked whales that were
tagged and exposed to simulated MFAS during the 2010 and 2011 field
seasons of the southern California behavioral response study. The 2011
whale was also incidentally exposed to MFAS from a distant naval
exercise. Received levels from the MFAS signals from the controlled and
incidental exposures were calculated as 84-144 and 78-106 dB re: 1
[mu]Pa rms, respectively. Both whales showed responses to the
controlled exposures, ranging from initial orientation changes to
avoidance responses characterized by energetic fluking and swimming
away from the source. However, the authors did not detect similar
responses to incidental exposure to distant naval sonar exercises at
comparable received levels, indicating that context of the exposures
(e.g., source proximity, controlled source ramp-up) may have been a
significant factor. Specifically, this result suggests that caution is
needed when using marine mammal response data collected from smaller,
nearer sound sources to predict at what received levels animals may
respond to larger sound sources that are significantly farther away--as
the distance of the source appears to be an important contextual
variable and animals may be less responsive to sources at notably
greater distances. Cuvier's beaked whale responses suggested particular
sensitivity to sound exposure as consistent with results for
Blainville's beaked whale. Similarly, beaked whales exposed to sonar
during British training exercises stopped foraging (DSTL, 2007), and
preliminary results of controlled playback of sonar may indicate
feeding/foraging disruption of killer whales and sperm whales (Miller
et al., 2011).
In the 2007-2008 Bahamas study, playback sounds of a potential
predator--a killer whale--resulted in a similar but more pronounced
reaction, which included longer inter-dive intervals and a sustained
straight-line departure of more than 20 km from the area (Boyd et al.,
2008; Southall et al., 2009; Tyack et al., 2011). The authors noted,
however, that the magnified reaction to the predator sounds could
represent a cumulative effect of exposure to the two sound types since
killer whale playback began approximately two hours after MF source
playback. Pilot whales and killer whales off Norway also exhibited
horizontal avoidance of a transducer with outputs in the mid-frequency
range (signals in the 1-2 kHz and 6-7 kHz ranges) (Miller et al.,
2011). Additionally, separation of a calf from its group during
exposure to MFAS playback was observed on one occasion (Miller et al.,
2011, 2012). Miller et al. (2012) noted that this single observed
mother-calf separation was unusual for several reasons, including the
fact that the experiment was conducted in an unusually narrow fjord
roughly one km wide and that the sonar exposure was started unusually
close to the pod including the calf. Both of these factors could have
contributed to calf separation. In contrast, preliminary analyses
suggest that none of the pilot whales or false killer whales in the
Bahamas showed an avoidance response to controlled exposure playbacks
(Southall et al., 2009).
In the 2010 BRS study, researchers again used controlled exposure
experiments to carefully measure behavioral responses of individual
animals to sound exposures of MFAS and pseudo-random noise. For each
sound type, some exposures were conducted when animals were in a
surface feeding (approximately 164 ft (50 m) or less) and/or
socializing behavioral state and others while animals were in a deep
feeding (greater than 164 ft (50 m)) and/or traveling mode. The
researchers conducted the largest number of controlled exposure
experiments on blue whales (n=19) and of these, 11 controlled exposure
experiments involved exposure to the MFAS sound type. For the majority
of controlled exposure experiment transmissions of either sound type,
they noted few obvious behavioral responses detected either by the
visual observers or on initial inspection of the tag data. The
researchers observed that throughout the controlled exposure experiment
transmissions, up to the highest received sound level (absolute RMS
value approximately 160 dB re: 1 [mu]Pa with signal-to-noise ratio
values over 60 dB), two blue whales continued surface feeding behavior
and remained at a range of around 3,820 ft (1,000 m) from the sound
source (Southall et al., 2011). In contrast, another blue whale (later
in the day and greater than 11.5 mi (18.5 km; 10 nmi) from the first
controlled exposure experiment location) exposed to the same stimulus
(MFA) while engaged in a deep feeding/travel state exhibited a
different response. In that case, the blue whale responded almost
immediately following the start of sound transmissions when received
sounds were just above ambient background levels (Southall et al.,
2011). The authors note that this kind of temporary avoidance behavior
was not evident in any of the nine controlled exposure experiments
involving blue whales

[[Page 33950]]

engaged in surface feeding or social behaviors, but was observed in
three of the ten controlled exposure experiments for blue whales in
deep feeding/travel behavioral modes (one involving MFA sonar; two
involving pseudo-random noise) (Southall et al., 2011). The results of
this study, as well as the results of the DeRuiter et al. (2013) study
of Cuvier's beaked whales discussed above, further illustrate the
importance of behavioral context in understanding and predicting
behavioral responses.
Through analysis of the behavioral response studies, a preliminary
overarching effect of greater sensitivity to all anthropogenic
exposures was seen in beaked whales compared to the other odontocetes
studied (Southall et al., 2009). Therefore, recent studies have focused
specifically on beaked whale responses to active sonar transmissions or
controlled exposure playback of simulated sonar on various military
ranges (Defence Science and Technology Laboratory, 2007; Claridge and
Durban, 2009; Moretti et al., 2009; McCarthy et al., 2011; Miller et
al., 2012; Southall et al., 2011, 2012a, 2012b, 2013, 2014; Tyack et
al., 2011). In the Bahamas, Blainville's beaked whales located on the
instrumented range will move off-range during sonar use and return only
after the sonar transmissions have stopped, sometimes taking several
days to do so (Claridge and Durban 2009; Moretti et al., 2009; McCarthy
et al., 2011; Tyack et al., 2011). Moretti et al. (2014) used
recordings from seafloor-mounted hydrophones at the Atlantic Undersea
Test and Evaluation Center (AUTEC) to analyze the probability of
Blainsville's beaked whale dives before, during, and after Navy sonar
exercises.
Southall et al. (2016) indicates that results from Tyack et al.
(2011), Miller et al. (2015), Stimpert et al. (2014), and DeRuiter et
al. (2013) beaked whale studies demonstrate clear, strong, and
pronounced but varied behavioral changes including avoidance with
associated energetic swimming and cessation of individual foraging
dives at quite low received levels (~100 to 135 dB re: 1 Pa) for
exposures to simulated or active MF military sonars (1-8 kHz) with
sound sources approximately 2-5 km away. Similar responses by beaked
whales to sonar have been documented by Stimpert et al., 2014, Falcone
et al., 2017, DiMarzio et al., 2018, and Joyce et al., 2019. However,
there are a number of variables influencing response or non-response
including source distance (close vs. far), received sound levels, and
other contextual variables such as other sound sources (e.g., vessels,
etc.) (Manzano-Roth et al., 2016, Falcone et al., 2017, Harris et al.,
2018). Wensveen et al. (2019) found northern bottlenose whales to avoid
sonar out to distances of 28 km, but these distances are well in line
with those observed on Navy ranges (Manzano-Roth et al., 2016; Joyce et
al., 2019) where the animals return once the sonar has ceased.
Furthermore, beaked whales have also shown response to other non-sonar
anthropogenic sounds such as commercial shipping and echosounders (Soto
et al., 2006, Pirotta et al., 2012, Cholewiak et al., 2017). Pirotta et
al. (2012) documented broadband ship noise causing a significant change
in beaked whale behavior up to at least 5.2 km away from the vessel.
Even though beaked whales appear to be sensitive to anthropogenic
sounds, the level of response at the population level does not appear
to be significant based on over a decade of research at two heavily
used Navy training areas in the Pacific (Falcone et al., 2012, Schorr
et al., 2014, DiMarzio et al., 2018, Schorr et al., 2019). With the
exception of seasonal patterns, DiMarzio et al. (2018) did not detect
any changes in annual Cuvier's beaked whale abundance estimates in
Southern California derived from passive acoustic echolocation
detections over nine years (2010-2018). Similar results for
Blainville's beaked whales abundance estimates over several years was
documented in Hawaii (Henderson et al., 2016;, DiMarzio et al., 2018).
Visually, there have been documented repeated sightings in southern
California of the same individual Cuvier's beaked whales over 10 years,
sightings of mother-calf pairs, and recently sightings of the same
mothers with their second calf (Falcone et al., 2012; Schorr et al.,
2014; Schorr et al., 2019; Schorr, unpublished data).
Baleen whales have shown a variety of responses to impulse sound
sources, including avoidance, reduced surface intervals, altered
swimming behavior, and changes in vocalization rates (Richardson et
al., 1995; Gordon et al., 2003; Southall, 2007). While most bowhead
whales did not show active avoidance until within 8 km of seismic
vessels (Richardson et al., 1995), some whales avoided vessels by more
than 20 km at received levels as low as 120 dB re: 1 [mu]Pa rms.
Additionally, Malme et al. (1988) observed clear changes in diving and
respiration patterns in bowheads at ranges up to 73 km from seismic
vessels, with received levels as low as 125 dB re: 1 [mu]Pa.
Gray whales migrating along the United States West Coast showed
avoidance responses to seismic vessels by 10 percent of animals at 164
dB re: 1 [micro]Pa, and by 90 percent of animals at 190 dB re: 1
[micro]Pa, with similar results for whales in the Bering Sea (Malme,
1986; 1988). In contrast, noise from seismic surveys was not found to
impact feeding behavior or exhalation rates while resting or diving in
western gray whales off the coast of Russia (Yazvenko et al., 2007;
Gailey et al., 2007).
Humpback whales showed avoidance behavior at ranges of five to
eight km from a seismic array during observational studies and
controlled exposure experiments in western Australia (McCauley, 1998;
Todd et al., 1996). Todd et al. (1996) found no clear short-term
behavioral responses by foraging humpbacks to explosions associated
with construction operations in Newfoundland, but did see a trend of
increased rates of net entanglement and a shift to a higher incidence
of net entanglement closer to the noise source.
The strongest baleen whale response in any behavioral response
study was observed in a minke whale in the 3S2 study, which responded
at 146 dB re: 1 [micro]Pa by strongly avoiding the sound source
(Kvadsheim et al., 2017; Sivle et al., 2015). Although the minke whale
increased its swim speed, directional movement, and respiration rate,
none of these were greater than rates observed in baseline behavior,
and its dive behavior remained similar to baseline dives. A minke whale
tagged in the Southern California behavioral response study also
responded by increasing its directional movement, but maintained its
speed and dive patterns, and so did not demonstrate as strong of a
response (Kvadsheim et al., 2017). In addition, the 3S2 minke whale
demonstrated some of the same avoidance behavior during the controlled
ship approach with no sonar, indicating at least some of the response
was to the vessel (Kvadsheim et al., 2017). Martin et al. (2015) found
that the density of calling minke whales was reduced during periods of
Navy training involving sonar relative to the periods before training,
and increased again in the days after training was completed. The
responses of individual whales could not be assessed, so in this case
it is unknown whether the decrease in calling animals indicated that
the animals left the range, or simply ceased calling. Similarly, minke
whale detections made using Marine Acoustic Recording Instruments off
Jacksonville, FL, were reduced or ceased altogether during periods of
sonar use (Simeone et al., 2015; U.S. Department of the Navy, 2013b),
especially with an increased ping rate (Charif et al., 2015).

[[Page 33951]]

Orientation
A shift in an animal's resting state or an attentional change via
an orienting response represent behaviors that would be considered mild
disruptions if occurring alone. As previously mentioned, the responses
may co-occur with other behaviors; for instance, an animal may
initially orient toward a sound source, and then move away from it.
Thus, any orienting response should be considered in context of other
reactions that may occur.
Continued Pre-Disturbance Behavior and Habituation
Under some circumstances, some of the individual marine mammals
that are exposed to active sonar transmissions will continue their
normal behavioral activities. In other circumstances, individual
animals will respond to sonar transmissions at lower received levels
and move to avoid additional exposure or exposures at higher received
levels (Richardson et al., 1995).
It is difficult to distinguish between animals that continue their
pre-disturbance behavior without stress responses, animals that
continue their behavior but experience stress responses (that is,
animals that cope with disturbance), and animals that habituate to
disturbance (that is, they may have experienced low-level stress
responses initially, but those responses abated over time). Watkins
(1986) reviewed data on the behavioral reactions of fin, humpback,
right, and minke whales that were exposed to continuous, broadband low-
frequency shipping and industrial noise in Cape Cod Bay. He concluded
that underwater sound was the primary cause of behavioral reactions in
these species of whales and that the whales responded behaviorally to
acoustic stimuli within their respective hearing ranges. Watkins also
noted that whales showed the strongest behavioral reactions to sounds
in the 15 Hz to 28 kHz range, although negative reactions (avoidance,
interruptions in vocalizations, etc.) were generally associated with
sounds that were either unexpected, too loud, suddenly louder or
different, or perceived as being associated with a potential threat
(such as an approaching ship on a collision course). In particular,
whales seemed to react negatively when they were within 100 m of the
source or when received levels increased suddenly in excess of 12 dB
relative to ambient sounds. At other times, the whales ignored the
source of the signal and all four species habituated to these sounds.
Nevertheless, Watkins concluded that whales ignored most sounds in the
background of ambient noise, including sounds from distant human
activities even though these sounds may have had considerable energies
at frequencies well within the whales' range of hearing. Further, he
noted that of the whales observed, fin whales were the most sensitive
of the four species, followed by humpback whales; right whales were the
least likely to be disturbed and generally did not react to low-
amplitude engine noise. By the end of his period of study, Watkins
(1986) concluded that fin and humpback whales had generally habituated
to the continuous and broad-band noise of Cape Cod Bay while right
whales did not appear to change their response. As mentioned above,
animals that habituate to a particular disturbance may have experienced
low-level stress responses initially, but those responses abated over
time. In most cases, this likely means a lessened immediate potential
effect from a disturbance. However, there is cause for concern where
the habituation occurs in a potentially more harmful situation. For
example, animals may become more vulnerable to vessel strikes once they
habituate to vessel traffic (Swingle et al., 1993; Wiley et al., 1995).
Aicken et al. (2005) monitored the behavioral responses of marine
mammals to a new low-frequency active sonar system used by the British
Navy (the United States Navy considers this to be a mid-frequency
source as it operates at frequencies greater than 1,000 Hz). During
those trials, fin whales, sperm whales, Sowerby's beaked whales, long-
finned pilot whales, Atlantic white-sided dolphins, and common
bottlenose dolphins were observed and their vocalizations were
recorded. These monitoring studies detected no evidence of behavioral
responses that the investigators could attribute to exposure to the
low-frequency active sonar during these trials.

Explosive Sources

Underwater explosive detonations send a shock wave and sound energy
through the water and can release gaseous by-products, create an
oscillating bubble, or cause a plume of water to shoot up from the
water surface. The shock wave and accompanying noise are of most
concern to marine animals. Depending on the intensity of the shock wave
and size, location, and depth of the animal, an animal can be injured,
killed, suffer non-lethal physical effects, experience hearing related
effects with or without behavioral responses, or exhibit temporary
behavioral responses or tolerance from hearing the blast sound.
Generally, exposures to higher levels of impulse and pressure levels
would result in greater impacts to an individual animal.
Injuries resulting from a shock wave take place at boundaries
between tissues of different densities. Different velocities are
imparted to tissues of different densities, and this can lead to their
physical disruption. Blast effects are greatest at the gas-liquid
interface (Landsberg, 2000). Gas-containing organs, particularly the
lungs and gastrointestinal tract, are especially susceptible (Goertner,
1982; Hill, 1978; Yelverton et al., 1973). Intestinal walls can bruise
or rupture, with subsequent hemorrhage and escape of gut contents into
the body cavity. Less severe gastrointestinal tract injuries include
contusions, petechiae (small red or purple spots caused by bleeding in
the skin), and slight hemorrhaging (Yelverton et al., 1973).
Because the ears are the most sensitive to pressure, they are the
organs most sensitive to injury (Ketten, 2000). Sound-related damage
associated with sound energy from detonations can be theoretically
distinct from injury from the shock wave, particularly farther from the
explosion. If a noise is audible to an animal, it has the potential to
damage the animal's hearing by causing decreased sensitivity (Ketten,
1995). Lethal impacts are those that result in immediate death or
serious debilitation in or near an intense source and are not,
technically, pure acoustic trauma (Ketten, 1995). Sublethal impacts
include hearing loss, which is caused by exposures to perceptible
sounds. Severe damage (from the shock wave) to the ears includes
tympanic membrane rupture, fracture of the ossicles, damage to the
cochlea, hemorrhage, and cerebrospinal fluid leakage into the middle
ear. Moderate injury implies partial hearing loss due to tympanic
membrane rupture and blood in the middle ear. Permanent hearing loss
also can occur when the hair cells are damaged by one very loud event,
as well as by prolonged exposure to a loud noise or chronic exposure to
noise. The level of impact from blasts depends on both an animal's
location and, at outer zones, on its sensitivity to the residual noise
(Ketten, 1995).

Further Potential Effects of Behavioral Disturbance on Marine Mammal
Fitness

The different ways that marine mammals respond to sound are
sometimes indicators of the ultimate effect that exposure to a given
stimulus will have on the well-being (survival, reproduction, etc.) of
an animal. There

[[Page 33952]]

are few quantitative marine mammal data relating the exposure of marine
mammals to sound to effects on reproduction or survival, though data
exists for terrestrial species to which we can draw comparisons for
marine mammals. Several authors have reported that disturbance stimuli
may cause animals to abandon nesting and foraging sites (Sutherland and
Crockford, 1993); may cause animals to increase their activity levels
and suffer premature deaths or reduced reproductive success when their
energy expenditures exceed their energy budgets (Daan et al., 1996;
Feare, 1976; Mullner et al., 2004); or may cause animals to experience
higher predation rates when they adopt risk-prone foraging or migratory
strategies (Frid and Dill, 2002). Each of these studies addressed the
consequences of animals shifting from one behavioral state (e.g.,
resting or foraging) to another behavioral state (e.g., avoidance or
escape behavior) because of human disturbance or disturbance stimuli.
One consequence of behavioral avoidance results in the altered
energetic expenditure of marine mammals because energy is required to
move and avoid surface vessels or the sound field associated with
active sonar (Frid and Dill, 2002). Most animals can avoid that
energetic cost by swimming away at slow speeds or speeds that minimize
the cost of transport (Miksis-Olds, 2006), as has been demonstrated in
Florida manatees (Miksis-Olds, 2006).
Those energetic costs increase, however, when animals shift from a
resting state, which is designed to conserve an animal's energy, to an
active state that consumes energy the animal would have conserved had
it not been disturbed. Marine mammals that have been disturbed by
anthropogenic noise and vessel approaches are commonly reported to
shift from resting to active behavioral states, which would imply that
they incur an energy cost.
Morete et al. (2007) reported that undisturbed humpback whale cows
that were accompanied by their calves were frequently observed resting
while their calves circled them (milling). When vessels approached, the
amount of time cows and calves spent resting and milling, respectively,
declined significantly. These results are similar to those reported by
Scheidat et al. (2004) for the humpback whales they observed off the
coast of Ecuador.
Constantine and Brunton (2001) reported that bottlenose dolphins in
the Bay of Islands, New Zealand engaged in resting behavior just 5
percent of the time when vessels were within 300 m, compared with 83
percent of the time when vessels were not present. However, Heenehan et
al. (2016) report that results of a study of the response of Hawaiian
spinner dolphins to human disturbance suggest that the key factor is
not the sheer presence or magnitude of human activities, but rather the
directed interactions and dolphin-focused activities that elicit
responses from dolphins at rest. This information again illustrates the
importance of context in regard to whether an animal will respond to a
stimulus. Miksis-Olds (2006) and Miksis-Olds et al. (2005) reported
that Florida manatees in Sarasota Bay, Florida, reduced the amount of
time they spent milling and increased the amount of time they spent
feeding when background noise levels increased. Although the acute
costs of these changes in behavior are not likely to exceed an animal's
ability to compensate, the chronic costs of these behavioral shifts are
uncertain.
Attention is the cognitive process of selectively concentrating on
one aspect of an animal's environment while ignoring other things
(Posner, 1994). Because animals (including humans) have limited
cognitive resources, there is a limit to how much sensory information
they can process at any time. The phenomenon called ``attentional
capture'' occurs when a stimulus (usually a stimulus that an animal is
not concentrating on or attending to) ``captures'' an animal's
attention. This shift in attention can occur consciously or
subconsciously (for example, when an animal hears sounds that it
associates with the approach of a predator) and the shift in attention
can be sudden (Dukas, 2002; van Rij, 2007). Once a stimulus has
captured an animal's attention, the animal can respond by ignoring the
stimulus, assuming a ``watch and wait'' posture, or treat the stimulus
as a disturbance and respond accordingly, which includes scanning for
the source of the stimulus or ``vigilance'' (Cowlishaw et al., 2004).
Vigilance is normally an adaptive behavior that helps animals
determine the presence or absence of predators, assess their distance
from conspecifics, or to attend cues from prey (Bednekoff and Lima,
1998; Treves, 2000). Despite those benefits, however, vigilance has a
cost of time; when animals focus their attention on specific
environmental cues, they are not attending to other activities such as
foraging or resting. These effects have generally not been demonstrated
for marine mammals, but studies involving fish and terrestrial animals
have shown that increased vigilance may substantially reduce feeding
rates (Saino, 1994; Beauchamp and Livoreil, 1997; Fritz et al., 2002;
Purser and Radford, 2011). Animals will spend more time being vigilant,
which may translate to less time foraging or resting, when disturbance
stimuli approach them more directly, remain at closer distances, have a
greater group size (e.g., multiple surface vessels), or when they co-
occur with times that an animal perceives increased risk (e.g., when
they are giving birth or accompanied by a calf). An example of this
concept with terrestrial species involved bighorn sheep and Dall's
sheep, which dedicated more time being vigilant, and less time resting
or foraging, when aircraft made direct approaches over them (Frid,
2001; Stockwell et al., 1991). Vigilance has also been documented in
pinnipeds at haul-out sites where resting may be disturbed when seals
become alerted and/or flush into the water due to a variety of
disturbances, which may be anthropogenic (noise and/or visual stimuli)
or due to other natural causes such as other pinnipeds (Richardson et
al., 1995; Southall et al., 2007; VanBlaricom, 2010; and Lozano and
Hente, 2014).
Chronic disturbance can cause population declines through reduction
of fitness (e.g., decline in body condition) and subsequent reduction
in reproductive success, survival, or both (e.g., Harrington and
Veitch, 1992; Daan et al., 1996; Bradshaw et al., 1998). For example,
Madsen (1994) reported that pink-footed geese (Anser brachyrhynchus) in
undisturbed habitat gained body mass and had about a 46 percent
reproductive success rate compared with geese in disturbed habitat
(being consistently scared off the fields on which they were foraging)
which did not gain mass and had a 17 percent reproductive success rate.
Similar reductions in reproductive success have been reported for mule
deer (Odocoileus hemionus) disturbed by all-terrain vehicles (Yarmoloy
et al., 1988), caribou (Rangifer tarandus caribou) disturbed by seismic
exploration blasts (Bradshaw et al., 1998), and caribou disturbed by
low-elevation military jet fights (Luick et al., 1996, Harrington and
Veitch, 1992). Similarly, a study of elk (Cervus elaphus) that were
disturbed experimentally by pedestrians concluded that the ratio of
young to mothers was inversely related to disturbance rate (Phillips
and Alldredge, 2000). However, Ridgway et al. (2006) reported that
increased vigilance in bottlenose dolphins exposed to sound over a
five-day period in open-air, open-water enclosures in

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San Diego Bay did not cause any sleep deprivation or stress effects
such as changes in cortisol or epinephrine levels.
The primary mechanism by which increased vigilance and disturbance
appear to affect the fitness of individual animals is by disrupting an
animal's time budget and, as a result, reducing the time they might
spend foraging and resting (which increases an animal's activity rate
and energy demand while decreasing their caloric intake/energy). An
example of this concept with terrestrial species involved a study of
grizzly bears (Ursus horribilis) that reported that bears disturbed by
hikers reduced their energy intake by an average of 12 kilocalories/min
(50.2 x 103 kiloJoules/min), and spent energy fleeing or acting
aggressively toward hikers (White et al., 1999).
Lusseau and Bejder (2007) present data from three long-term studies
illustrating the connections between disturbance from whale-watching
boats and population-level effects in cetaceans. In Shark Bay
Australia, the abundance of bottlenose dolphins was compared within
adjacent control and tourism sites over three consecutive 4.5-year
periods of increasing tourism levels. Between the second and third time
periods, in which tourism doubled, dolphin abundance decreased by 15
percent in the tourism area and did not change significantly in the
control area. In Fiordland, New Zealand, two populations (Milford and
Doubtful Sounds) of bottlenose dolphins with tourism levels that
differed by a factor of seven were observed and significant increases
in travelling time and decreases in resting time were documented for
both. Consistent short-term avoidance strategies were observed in
response to tour boats until a threshold of disturbance was reached
(average 68 minutes between interactions), after which the response
switched to a longer-term habitat displacement strategy. For one
population, tourism only occurred in a part of the home range. However,
tourism occurred throughout the home range of the Doubtful Sound
population and once boat traffic increased beyond the 68-minute
threshold (resulting in abandonment of their home range/preferred
habitat), reproductive success drastically decreased (increased
stillbirths) and abundance decreased significantly (from 67 to 56
individuals in a short period). Last, in a study of northern resident
killer whales off Vancouver Island, exposure to boat traffic was shown
to reduce foraging opportunities and increase traveling time. A simple
bioenergetics model was applied to show that the reduced foraging
opportunities equated to a decreased energy intake of 18 percent, while
the increased traveling incurred an increased energy output of 3-4
percent, which suggests that a management action based on avoiding
interference with foraging might be particularly effective.
On a related note, many animals perform vital functions, such as
feeding, resting, traveling, and socializing, on a diel cycle (24-hr
cycle). Behavioral reactions to noise exposure (such as disruption of
critical life functions, displacement, or avoidance of important
habitat) are more likely to be significant for fitness if they last
more than one diel cycle or recur on subsequent days (Southall et al.,
2007). Consequently, a behavioral response lasting less than one day
and not recurring on subsequent days is not considered particularly
severe unless it could directly affect reproduction or survival
(Southall et al., 2007). It is important to note the difference between
behavioral reactions lasting or recurring over multiple days and
anthropogenic activities lasting or recurring over multiple days. For
example, just because at-sea exercises last for multiple days does not
necessarily mean that individual animals will be either exposed to
those activity-related stressors (i.e., sonar) for multiple days or
further, exposed in a manner that would result in sustained multi-day
substantive behavioral responses.
Stone (2015a) reported data from at-sea observations during 1,196
airgun surveys from 1994 to 2010. When large arrays of airguns
(considered to be 500 in\3\ or more) were firing, lateral displacement,
more localized avoidance, or other changes in behavior were evident for
most odontocetes. However, significant responses to large arrays were
found only for the minke whale and fin whale. Behavioral responses
observed included changes in swimming or surfacing behavior, with
indications that cetaceans remained near the water surface at these
times. Cetaceans were recorded as feeding less often when large arrays
were active. Monitoring of gray whales during an air gun survey
included recording whale movements and respirations pre-, during-, and
post-seismic survey (Gailey et al., 2016). Behavioral state and water
depth were the best `natural' predictors of whale movements and
respiration and, after considering natural variation, none of the
response variables were significantly associated with survey or vessel
sounds.
In order to understand how the effects of activities may or may not
impact species and stocks of marine mammals, it is necessary to
understand not only what the likely disturbances are going to be, but
how those disturbances may affect the reproductive success and
survivorship of individuals, and then how those impacts to individuals
translate to population-level effects. Following on the earlier work of
a committee of the U.S. National Research Council (NRC, 2005), New et
al. (2014), in an effort termed the Potential Consequences of
Disturbance (PCoD), outline an updated conceptual model of the
relationships linking disturbance to changes in behavior and
physiology, health, vital rates, and population dynamics. In this
framework, behavioral and physiological changes can have direct (acute)
effects on vital rates, such as when changes in habitat use or
increased stress levels raise the probability of mother-calf separation
or predation; they can have indirect and long-term (chronic) effects on
vital rates, such as when changes in time/energy budgets or increased
disease susceptibility affect health, which then affects vital rates;
or they can have no effect to vital rates (New et al., 2014). In
addition to outlining this general framework and compiling the relevant
literature that supports it, the authors chose four example species for
which extensive long-term monitoring data exist (southern elephant
seals, North Atlantic right whales, Ziphidae beaked whales, and
bottlenose dolphins) and developed state-space energetic models that
can be used to forecast longer-term, population-level impacts from
behavioral changes. While these are very specific models with very
specific data requirements that cannot yet be applied broadly to
project-specific risk assessments for the majority of species, as well
as requiring significant resources and time to conduct (more than is
typically available to support regulatory compliance for one project),
they are a critical first step towards being able to quantify the
likelihood of a population level effect.
Since New et al. (2014), several publications have described models
developed to examine the long-term effects of environmental or
anthropogenic disturbance of foraging on various life stages of
selected species (sperm whale, Farmer et al. (2018); California sea
lion, McHuron et al. (2018); and blue whale, Pirotta, et al. (2018a)).
These models continue to add to refinement to the approaches to the
population consequences of disturbance (PCOD) framework. Such models
also help identify what data inputs require further investigation.
Pirotta et al.

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(2018b) provides a review of the PCOD framework with details on each
step of the process and approaches to applying real data or simulations
to achieve each step.

Stranding and Mortality

The definition for a stranding under title IV of the MMPA is that
(A) a marine mammal is dead and is (i) on a beach or shore of the
United States; or (ii) in waters under the jurisdiction of the United
States (including any navigable waters); or (B) a marine mammal is
alive and is (i) on a beach or shore of the United States and is unable
to return to the water; (ii) on a beach or shore of the United States
and, although able to return to the water, is in need of apparent
medical attention; or (iii) in the waters under the jurisdiction of the
United States (including any navigable waters), but is unable to return
to its natural habitat under its own power or without assistance (see
MMPA section 410(3)). This definition is useful for considering
stranding events even when they occur beyond lands and waters under the
jurisdiction of the United States.
Marine mammal strandings have been linked to a variety of causes,
such as illness from exposure to infectious agents, biotoxins, or
parasites; starvation; unusual oceanographic or weather events; or
anthropogenic causes including fishery interaction, ship strike,
entrainment, entrapment, sound exposure, or combinations of these
stressors sustained concurrently or in series. Historically, the cause
or causes of most strandings have remained unknown (Geraci et al.,
1976; Eaton, 1979, Odell et al., 1980; Best, 1982), but the development
of trained, professional stranding response networks and improved
analyses have led to a greater understanding of marine mammal stranding
causes (Simeone and Moore 2017).
Numerous studies suggest that the physiology, behavior, habitat,
social relationships, age, or condition of cetaceans may cause them to
strand or might predispose them to strand when exposed to another
phenomenon. These suggestions are consistent with the conclusions of
numerous other studies that have demonstrated that combinations of
dissimilar stressors commonly combine to kill an animal or dramatically
reduce its fitness, even though one exposure without the other does not
produce the same result (Bernaldo de Quiros et al., 2019; Chroussos,
2000; Creel, 2005; DeVries et al., 2003; Fair and Becker, 2000; Foley
et al., 2001; Moberg, 2000; Relyea, 2005a; 2005b, Romero, 2004; Sih et
al., 2004).
Historically, stranding reporting and response efforts have been
inconsistent, although significant improvements have occurred over the
last 25 years. Reporting forms for basic (``Level A'') information,
rehabilitation disposition, and human interaction have been
standardized nationally (available at https://www.fisheries.noaa.gov/
national/marine-mammal-protection/level-data-collection-marine-mammal-
stranding-events). However, data collected beyond basic information
varies by region (and may vary from case to case), and are not
standardized across the United States. Logistical conditions such as
weather, time, location, and decomposition state may also affect the
ability of the stranding network to thoroughly examine a specimen
(Carretta et al., 2016b; Moore et al., 2013). While the investigation
of stranded animals provides insight into the types of threats marine
mammal populations face, full investigations are only possible and
conducted on a small fraction of the total number of strandings that
occur, limiting our understanding of the causes of strandings (Carretta
et al., 2016a). Additionally, and due to the variability in effort and
data collected, the ability to interpret long-term trends in stranded
marine mammals is complicated.
In the United States from 2006-2017, there were 19,430 cetacean
strandings and 55,833 pinniped strandings (75,263 total) (P. Onens,
NMFS, pers comm., 2019). Several mass strandings (strandings that
involve two or more individuals of the same species, excluding a single
mother-calf pair) that have occurred over the past two decades have
been associated with anthropogenic activities that introduced sound
into the marine environment such as naval operations and seismic
surveys. An in-depth discussion of strandings is in the Navy's
Technical Report on Marine Mammal Strandings Associated with U.S. Navy
Sonar Activities (U.S. Navy Marine Mammal Program & Space and Naval
Warfare Systems Command Center Pacific, 2017).
Worldwide, there have been several efforts to identify
relationships between cetacean mass stranding events and military
active sonar (Cox et al., 2006, Hildebrand, 2004; IWC, 2005; Taylor et
al., 2004). For example, based on a review of mass stranding events
around the world consisting of two or more individuals of Cuvier's
beaked whales, records from the International Whaling Commission (IWC)
(2005) show that a quarter (9 of 41) were associated with concurrent
naval patrol, explosion, maneuvers, or MFAS. D'Amico et al. (2009)
reviewed beaked whale stranding data compiled primarily from the
published literature, which provides an incomplete record of stranding
events, as many are not written up for publication, along with
unpublished information from some regions of the world.
Most of the stranding events reviewed by the IWC involved beaked
whales. A mass stranding of Cuvier's beaked whales in the eastern
Mediterranean Sea occurred in 1996 (Frantzis, 1998), and mass stranding
events involving Gervais' beaked whales, Blainville's beaked whales,
and Cuvier's beaked whales occurred off the coast of the Canary Islands
in the late 1980s (Simmonds and Lopez-Jurado, 1991). The stranding
events that occurred in the Canary Islands and Kyparissiakos Gulf in
the late 1990s and the Bahamas in 2000 have been the most intensively-
studied mass stranding events and have been associated with naval
maneuvers involving the use of tactical sonar. Other cetacean species
with naval sonar implicated in stranding events include harbor porpoise
(Phocoena phocoena) (Norman et al., 2004, Wright et al., 2013) and
common dolphin (Delphinus delphis) (Jepson and Deaville 2009).

Strandings Associated With Impulsive Sound

Silver Strand
During a Navy training event on March 4, 2011 at the Silver Strand
Training Complex in San Diego, California, three or possibly four
dolphins were killed in an explosion. During an underwater detonation
training event, a pod of 100 to 150 long-beaked common dolphins were
observed moving towards the 700-yd (640.1 m) exclusion zone around the
explosive charge, monitored by personnel in a safety boat and
participants in a dive boat. Approximately five minutes remained on a
time-delay fuse connected to a single 8.76 lb (3.97 kg) explosive
charge (C-4 and detonation cord). Although the dive boat was placed
between the pod and the explosive in an effort to guide the dolphins
away from the area, that effort was unsuccessful and three long-beaked
common dolphins near the explosion died. In addition to the three
dolphins found dead on March 4, the remains of a fourth dolphin were
discovered on March 7, 2011 near Oceanside, California (3 days later
and approximately 68 km north of the detonation), which might also have
been related to this event. Association of the

[[Page 33955]]

fourth stranding with the training event is uncertain because dolphins
strand on a regular basis in the San Diego area. Details such as the
dolphins' depth and distance from the explosive at the time of the
detonation could not be estimated from the 250 yd (228.6 m) standoff
point of the observers in the dive boat or the safety boat.
These dolphin mortalities are the only known occurrence of a U.S.
Navy training or testing event involving impulsive energy (underwater
detonation) that caused mortality or injury to a marine mammal. Despite
this being a rare occurrence, the Navy reviewed training requirements,
safety procedures, and possible mitigation measures and implemented
changes to reduce the potential for this to occur in the future.
Discussions of procedures associated with underwater explosives
training and other training events are presented in the Proposed
Mitigation Measures section.
Kyle of Durness, Scotland
On July 22, 2011 a mass stranding event involving long-finned pilot
whales occurred at Kyle of Durness, Scotland. An investigation by
Brownlow et al. (2015) considered unexploded ordnance detonation
activities at a Ministry of Defense bombing range, conducted by the
Royal Navy prior to and during the strandings, as a plausible
contributing factor in the mass stranding event. While Brownlow et al.
(2015) concluded that the serial detonations of underwater ordnance
were an influential factor in the mass stranding event (along with the
presence of a potentially compromised animal and navigational error in
a topographically complex region), they also suggest that mitigation
measures--which included observations from a zodiac only and by
personnel not experienced in marine mammal observation, among other
deficiencies--were likely insufficient to assess if cetaceans were in
the vicinity of the detonations. The authors also cite information from
the Ministry of Defense indicating ``an extraordinarily high level of
activity'' (i.e., frequency and intensity of underwater explosions) on
the range in the days leading up to the stranding.
Gulf of California, Mexico
One stranding event was contemporaneous with and reasonably
associated spatially with the use of seismic air guns. This event
occurred in the Gulf of California, coincident with seismic reflection
profiling by the R/V Maurice Ewing operated by Columbia University's
Lamont-Doherty Earth Observatory and involved two Cuvier's beaked
whales (Hildebrand, 2004). The vessel had been firing an array of 20
air guns with a total volume of 8,500 in\3\ (Hildebrand, 2004; Taylor
et al., 2004).

Strandings Associated With Active Sonar

Over the past 21 years, there have been five stranding events
coincident with U.S. Navy MF active sonar use in which exposure to
sonar is believed to have been a contributing factor: Greece (1996);
the Bahamas (2000); Madeira (2000); Canary Islands (2002); and Spain
(2006) (Cox et al., 2006; Fernandez, 2006; U.S. Navy Marine Mammal
Program & Space and Naval Warfare Systems Command Center Pacific,
2017). These five mass strandings have resulted in about 40 known
cetacean deaths consisting mostly of beaked whales and with close
linkages to mid-frequency active sonar activity. In these
circumstances, exposure to non-impulsive acoustic energy was considered
a potential indirect cause of death of the marine mammals (Cox et al.,
2006). Only one of these stranding events, the Bahamas (2000), was
associated with exercises conducted by the U.S. Navy. Additionally, in
2004, during the Rim of the Pacific (RIMPAC) exercises, between 150 and
200 usually pelagic melon-headed whales occupied the shallow waters of
Hanalei Bay, Kauai, Hawaii for over 28 hours. NMFS determined that MFAS
was a plausible, if not likely, contributing factor in what may have
been a confluence of events that led to the Hanalei Bay stranding. A
number of other stranding events coincident with the operation of MFAS,
including the death of beaked whales or other species (minke whales,
dwarf sperm whales, pilot whales), have been reported; however, the
majority have not been investigated to the degree necessary to
determine the cause of the stranding. Most recently, the Independent
Scientific Review Panel investigating potential contributing factors to
a 2008 mass stranding of melon-headed whales in Antsohihy, Madagascar
released its final report suggesting that the stranding was likely
initially triggered by an industry seismic survey (Southall et al.,
2013). This report suggests that the operation of a commercial high-
powered 12 kHz multi-beam echosounder during an industry seismic survey
was a plausible and likely initial trigger that caused a large group of
melon-headed whales to leave their typical habitat and then ultimately
strand as a result of secondary factors such as malnourishment and
dehydration. The report indicates that the risk of this particular
convergence of factors and ultimate outcome is likely very low, but
recommends that the potential be considered in environmental planning.
Because of the association between tactical mid-frequency active sonar
use and a small number of marine mammal strandings, the Navy and NMFS
have been considering and addressing the potential for strandings in
association with Navy activities for years. In addition to the proposed
mitigation measures intended to more broadly minimize impacts to marine
mammals, the Navy will abide by the Notification and Reporting Plan,
which sets out notification, reporting, and other requirements when
dead, injured, or stranded marine mammals are detected in certain
circumstances.
Greece (1996)
Twelve Cuvier's beaked whales stranded atypically (in both time and
space) along a 38.2-km strand of the Kyparissiakos Gulf coast on May 12
and 13, 1996 (Frantzis, 1998). From May 11 through May 15, the North
Atlantic Treaty Organization (NATO) research vessel Alliance was
conducting sonar tests with signals of 600 Hz and 3 kHz and source
levels of 228 and 226 dB re: 1[mu]Pa, respectively (D'Amico and
Verboom, 1998; D'Spain et al., 2006). The timing and location of the
testing encompassed the time and location of the strandings (Frantzis,
1998).
Necropsies of eight of the animals were performed but were limited
to basic external examination and sampling of stomach contents, blood,
and skin. No ears or organs were collected, and no histological samples
were preserved. No significant apparent abnormalities or wounds were
found, however examination of photos of the animals, taken soon after
their death, revealed that the eyes of at least four of the individuals
were bleeding (Frantzis, 2004). Stomach contents contained the flesh of
cephalopods, indicating that feeding had recently taken place
(Frantzis, 1998).
All available information regarding the conditions associated with
this stranding event was compiled, and many potential causes were
examined including major pollution events, prominent tectonic activity,
unusual physical or meteorological events, magnetic anomalies,
epizootics, and conventional military activities (International Council
for the Exploration of the Sea, 2005a). However, none of these
potential causes coincided in time or space with the mass stranding, or
could explain its characteristics (International Council for the
Exploration of the Sea, 2005a). The robust condition of the animals,
plus the

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recent stomach contents, is inconsistent with pathogenic causes. In
addition, environmental causes can be ruled out as there were no
unusual environmental circumstances or events before or during this
time period and within the general proximity (Frantzis, 2004).
Because of the rarity of this mass stranding of Cuvier's beaked
whales in the Kyparissiakos Gulf (first one in historical records), the
probability for the two events (the military exercises and the
strandings) to coincide in time and location, while being independent
of each other, was thought to be extremely low (Frantzis, 1998).
However, because full necropsies had not been conducted, and no
abnormalities were noted, the cause of the strandings could not be
precisely determined (Cox et al., 2006). A Bioacoustics Panel convened
by NATO concluded that the evidence available did not allow them to
accept or reject sonar exposures as a causal agent in these stranding
events. The analysis of this stranding event provided support for, but
no clear evidence for, the cause-and-effect relationship of tactical
sonar training activities and beaked whale strandings (Cox et al.,
2006).
Bahamas (2000)
NMFS and the Navy prepared a joint report addressing the multi-
species stranding in the Bahamas in 2000, which took place within 24
hrs of U.S. Navy ships using MFAS as they passed through the Northeast
and Northwest Providence Channels on March 15-16, 2000. The ships,
which operated both AN/SQS-53C and AN/SQS-56, moved through the channel
while emitting sonar pings approximately every 24 seconds. Of the 17
cetaceans that stranded over a 36-hour period (Cuvier's beaked whales,
Blainville's beaked whales, minke whales, and a spotted dolphin), seven
animals died on the beach (five Cuvier's beaked whales, one
Blainville's beaked whale, and the spotted dolphin), while the other 10
were returned to the water alive (though their ultimate fate is
unknown). As discussed in the Bahamas report (DOC/DON, 2001), there is
no likely association between the minke whale and spotted dolphin
strandings and the operation of MFAS.
Necropsies were performed on five of the stranded beaked whales.
All five necropsied beaked whales were in good body condition, showing
no signs of infection, disease, ship strike, blunt trauma, or fishery
related injuries, and three still had food remains in their stomachs.
Auditory structural damage was discovered in four of the whales,
specifically bloody effusions or hemorrhaging around the ears.
Bilateral intracochlear and unilateral temporal region subarachnoid
hemorrhage, with blood clots in the lateral ventricles, were found in
two of the whales. Three of the whales had small hemorrhages in their
acoustic fats (located along the jaw and in the melon).
A comprehensive investigation was conducted and all possible causes
of the stranding event were considered, whether they seemed likely at
the outset or not. Based on the way in which the strandings coincided
with ongoing naval activity involving tactical MFAS use, in terms of
both time and geography, the nature of the physiological effects
experienced by the dead animals, and the absence of any other acoustic
sources, the investigation team concluded that MFAS aboard U.S. Navy
ships that were in use during the active sonar exercise in question
were the most plausible source of this acoustic or impulse trauma to
beaked whales. This sound source was active in a complex environment
that included the presence of a surface duct, unusual and steep
bathymetry, a constricted channel with limited egress, intensive use of
multiple, active sonar units over an extended period of time, and the
presence of beaked whales that appear to be sensitive to the
frequencies produced by these active sonars. The investigation team
concluded that the cause of this stranding event was the confluence of
the Navy MFAS and these contributory factors working together, and
further recommended that the Navy avoid operating MFAS in situations
where these five factors would be likely to occur. This report does not
conclude that all five of these factors must be present for a stranding
to occur, nor that beaked whales are the only species that could
potentially be affected by the confluence of the other factors. Based
on this, NMFS believes that the operation of MFAS in situations where
surface ducts exist, or in marine environments defined by steep
bathymetry and/or constricted channels may increase the likelihood of
producing a sound field with the potential to cause cetaceans
(especially beaked whales) to strand, and therefore, suggests the need
for increased vigilance while operating MFAS in these areas, especially
when beaked whales (or potentially other deep divers) are likely
present.
Madeira, Portugal (2000)
From May 10-14, 2000, three Cuvier's beaked whales were found
atypically stranded on two islands in the Madeira archipelago, Portugal
(Cox et al., 2006). A fourth animal was reported floating in the
Madeiran waters by fisherman but did not come ashore (Woods Hole
Oceanographic Institution, 2005). Joint NATO amphibious training
peacekeeping exercises involving participants from 17 countries and 80
warships, took place in Portugal during May 2-15, 2000.
The bodies of the three stranded whales were examined post mortem
(Woods Hole Oceanographic Institution, 2005), though only one of the
stranded whales was fresh enough (24 hours after stranding) to be
necropsied (Cox et al., 2006). Results from the necropsy revealed
evidence of hemorrhage and congestion in the right lung and both
kidneys (Cox et al., 2006). There was also evidence of intercochlear
and intracranial hemorrhage similar to that which was observed in the
whales that stranded in the Bahamas event (Cox et al., 2006). There
were no signs of blunt trauma, and no major fractures (Woods Hole
Oceanographic Institution, 2005). The cranial sinuses and airways were
found to be clear with little or no fluid deposition, which may
indicate good preservation of tissues (Woods Hole Oceanographic
Institution, 2005).
Several observations on the Madeira stranded beaked whales, such as
the pattern of injury to the auditory system, are the same as those
observed in the Bahamas strandings. Blood in and around the eyes,
kidney lesions, pleural hemorrhages, and congestion in the lungs are
particularly consistent with the pathologies from the whales stranded
in the Bahamas, and are consistent with stress and pressure related
trauma. The similarities in pathology and stranding patterns between
these two events suggest that a similar pressure event may have
precipitated or contributed to the strandings at both sites (Woods Hole
Oceanographic Institution, 2005).
Even though no definitive causal link can be made between the
stranding event and naval exercises, certain conditions may have
existed in the exercise area that, in their aggregate, may have
contributed to the marine mammal strandings (Freitas, 2004): Exercises
were conducted in areas of at least 547 fathoms (1,000 m) depth near a
shoreline where there is a rapid change in bathymetry on the order of
547 to 3,281 fathoms (1,000 to 6,000 m) occurring across a relatively
short horizontal distance (Freitas, 2004); multiple ships were
operating around Madeira, though it is not known if MFAS was used, and
the specifics of the sound sources used are unknown (Cox et al., 2006,
Freitas, 2004); and exercises took place in an area surrounded by
landmasses separated by less than 35 nmi (65 km) and at least 10 nmi
(19 km)

[[Page 33957]]

in length, or in an embayment. Exercises involving multiple ships
employing MFAS near land may produce sound directed towards a channel
or embayment that may cut off the lines of egress for marine mammals
(Freitas, 2004).
Canary Islands, Spain (2002)
The southeastern area within the Canary Islands is well known for
aggregations of beaked whales due to its ocean depths of greater than
547 fathoms (1,000 m) within a few hundred meters of the coastline
(Fernandez et al., 2005). On September 24, 2002, 14 beaked whales were
found stranded on Fuerteventura and Lanzarote Islands in the Canary
Islands (International Council for Exploration of the Sea, 2005a).
Seven whales died, while the remaining seven live whales were returned
to deeper waters (Fernandez et al., 2005). Four beaked whales were
found stranded dead over the next three days either on the coast or
floating offshore. These strandings occurred within close proximity of
an international naval exercise that utilized MFAS and involved
numerous surface warships and several submarines. Strandings began
about four hours after the onset of MFAS activity (International
Council for Exploration of the Sea, 2005a; Fernandez et al., 2005).
Eight Cuvier's beaked whales, one Blainville's beaked whale, and
one Gervais' beaked whale were necropsied, 6 of them within 12 hours of
stranding (Fernandez et al., 2005). No pathogenic bacteria were
isolated from the carcasses (Jepson et al., 2003). The animals
displayed severe vascular congestion and hemorrhage especially around
the tissues in the jaw, ears, brain, and kidneys, displaying marked
disseminated microvascular hemorrhages associated with widespread fat
emboli (Jepson et al., 2003; International Council for Exploration of
the Sea, 2005a). Several organs contained intravascular bubbles,
although definitive evidence of gas embolism in vivo is difficult to
determine after death (Jepson et al., 2003). The livers of the
necropsied animals were the most consistently affected organ, which
contained macroscopic gas-filled cavities and had variable degrees of
fibrotic encapsulation. In some animals, cavitary lesions had
extensively replaced the normal tissue (Jepson et al., 2003). Stomachs
contained a large amount of fresh and undigested contents, suggesting a
rapid onset of disease and death (Fernandez et al., 2005). Head and
neck lymph nodes were enlarged and congested, and parasites were found
in the kidneys of all animals (Fernandez et al., 2005).
The association of NATO MFAS use close in space and time to the
beaked whale strandings, and the similarity between this stranding
event and previous beaked whale mass strandings coincident with sonar
use, suggests that a similar scenario and causative mechanism of
stranding may be shared between the events. Beaked whales stranded in
this event demonstrated brain and auditory system injuries,
hemorrhages, and congestion in multiple organs, similar to the
pathological findings of the Bahamas and Madeira stranding events. In
addition, the necropsy results of the Canary Islands stranding event
lead to the hypothesis that the presence of disseminated and widespread
gas bubbles and fat emboli were indicative of nitrogen bubble
formation, similar to what might be expected in decompression sickness
(Jepson et al., 2003; Fern[aacute]ndez et al., 2005).
Hanalei Bay (2004)
On July 3 and 4, 2004, approximately 150 to 200 melon-headed whales
occupied the shallow waters of Hanalei Bay, Kauai, Hawaii for over 28
hrs. Attendees of a canoe blessing observed the animals entering the
Bay in a single wave formation at 7 a.m. on July 3, 2004. The animals
were observed moving back into the shore from the mouth of the Bay at 9
a.m. The usually pelagic animals milled in the shallow bay and were
returned to deeper water with human assistance beginning at 9:30 a.m.
on July 4, 2004, and were out of sight by 10:30 a.m.
Only one animal, a calf, was known to have died following this
event. The animal was noted alive and alone in the Bay on the afternoon
of July 4, 2004, and was found dead in the Bay the morning of July 5,
2004. A full necropsy, magnetic resonance imaging, and computerized
tomography examination were performed on the calf to determine the
manner and cause of death. The combination of imaging, necropsy and
histological analyses found no evidence of infectious, internal
traumatic, congenital, or toxic factors. Cause of death could not be
definitively determined, but it is likely that maternal separation,
poor nutritional condition, and dehydration contributed to the final
demise of the animal. Although it is not known when the calf was
separated from its mother, the animals' movement into the Bay and
subsequent milling and re-grouping may have contributed to the
separation or lack of nursing, especially if the maternal bond was weak
or this was an inexperienced mother with her first calf.
Environmental factors, abiotic and biotic, were analyzed for any
anomalous occurrences that would have contributed to the animals
entering and remaining in Hanalei Bay. The Bay's bathymetry is similar
to many other sites within the Hawaiian Island chain and dissimilar to
sites that have been associated with mass strandings in other parts of
the United States. The weather conditions appeared to be normal for
that time of year with no fronts or other significant features noted.
There was no evidence of unusual distribution, occurrence of predator
or prey species, or unusual harmful algal blooms, although Mobley et
al. (2007) suggested that the full moon cycle that occurred at that
time may have influenced a run of squid into the Bay. Weather patterns
and bathymetry that have been associated with mass strandings elsewhere
were not found to occur in this instance.
The Hanalei event was spatially and temporally correlated with
RIMPAC. Official sonar training and tracking exercises in the Pacific
Missile Range Facility (PMRF) warning area did not commence until
approximately 8 a.m. on July 3 and were thus ruled out as a possible
trigger for the initial movement into the bay. However, six naval
surface vessels transiting to the operational area on July 2
intermittently transmitted active sonar (for approximately nine hours
total from 1:15 p.m. to 12:30 a.m.) as they approached from the south.
The potential for these transmissions to have triggered the whales'
movement into Hanalei Bay was investigated. Analyses with the
information available indicated that animals to the south and east of
Kaua'i could have detected active sonar transmissions on July 2, and
reached Hanalei Bay on or before 7 a.m. on July 3. However, data
limitations regarding the position of the whales prior to their arrival
in the Bay, the magnitude of sonar exposure, behavioral responses of
melon-headed whales to acoustic stimuli, and other possible relevant
factors preclude a conclusive finding regarding the role of sonar in
triggering this event. Propagation modeling suggests that transmissions
from sonar use during the July 3 exercise in the PMRF warning area may
have been detectable at the mouth of the bay. If the animals responded
negatively to these signals, it may have contributed to their continued
presence in the bay. The U.S. Navy ceased all active sonar
transmissions during exercises in this range on the afternoon of July
3. Subsequent to the cessation of sonar

[[Page 33958]]

use, the animals were herded out of the bay.
While causation of this stranding event may never be unequivocally
determined, NMFS considers the active sonar transmissions of July 2-3,
2004, a plausible, if not likely, contributing factor in what may have
been a confluence of events. This conclusion is based on the following:
(1) The evidently anomalous nature of the stranding; (2) its close
spatiotemporal correlation with wide-scale, sustained use of sonar
systems previously associated with stranding of deep-diving marine
mammals; (3) the directed movement of two groups of transmitting
vessels toward the southeast and southwest coast of Kauai; (4) the
results of acoustic propagation modeling and an analysis of possible
animal transit times to the bay; and (5) the absence of any other
compelling causative explanation. The initiation and persistence of
this event may have resulted from an interaction of biological and
physical factors. The biological factors may have included the presence
of an apparently uncommon, deep-diving cetacean species (and possibly
an offshore, non-resident group), social interactions among the animals
before or after they entered the bay, and/or unknown predator or prey
conditions. The physical factors may have included the presence of
nearby deep water, multiple vessels transiting in a directed manner
while transmitting active sonar over a sustained period, the presence
of surface sound ducting conditions, and/or intermittent and random
human interactions while the animals were in the bay.
A separate event involving melon-headed whales and rough-toothed
dolphins took place over the same period of time in the Northern
Mariana Islands (Jefferson et al., 2006), which is several thousand
miles from Hawaii. Some 500 to 700 melon-headed whales came into
Sasanhaya Bay on July 4, 2004, near the island of Rota and then left of
their own accord after 5.5 hours; no known active sonar transmissions
occurred in the vicinity of that event. The Rota incident led to
scientific debate regarding what, if any, relationship the event had to
the simultaneous events in Hawaii and whether they might be related by
some common factor (e.g., there was a full moon on July 2, 2004, as
well as during other melon-headed whale strandings and nearshore
aggregations (Brownell et al., 2009; Lignon et al., 2007; Mobley et
al., 2007). Brownell et al. (2009) compared the two incidents, along
with one other stranding incident at Nuka Hiva in French Polynesia and
normal resting behaviors observed at Palmyra Island, in regard to
physical features in the areas, melon-headed whale behavior, and lunar
cycles. Brownell et al., (2009) concluded that the rapid entry of the
whales into Hanalei Bay, their movement into very shallow water far
from the 100-m contour, their milling behavior (typical pre-stranding
behavior), and their reluctance to leave the bay constituted an unusual
event that was not similar to the events that occurred at Rota, which
appear to be similar to observations of melon-headed whales resting
normally at Palmyra Island. Additionally, there was no correlation
between lunar cycle and the types of behaviors observed in the Brownell
et al. (2009) examples.
Spain (2006)
The Spanish Cetacean Society reported an atypical mass stranding of
four beaked whales that occurred January 26, 2006, on the southeast
coast of Spain, near Moj[aacute]car (Gulf of Vera) in the Western
Mediterranean Sea. According to the report, two of the whales were
discovered the evening of January 26 and were found to be still alive.
Two other whales were discovered during the day on January 27, but had
already died. The first three animals were located near the town of
Moj[aacute]car and the fourth animal was found dead, a few kilometers
north of the first three animals. From January 25-26, 2006, Standing
NATO Response Force Maritime Group Two (five of seven ships including
one U.S. ship under NATO Operational Control) had conducted active
sonar training against a Spanish submarine within 50 nmi (93 km) of the
stranding site.
Veterinary pathologists necropsied the two male and two female
Cuvier's beaked whales. According to the pathologists, the most likely
primary cause of this type of beaked whale mass stranding event was
anthropogenic acoustic activities, most probably anti-submarine MFAS
used during the military naval exercises. However, no positive acoustic
link was established as a direct cause of the stranding. Even though no
causal link can be made between the stranding event and naval
exercises, certain conditions may have existed in the exercise area
that, in their aggregate, may have contributed to the marine mammal
strandings (Freitas, 2004). Exercises were conducted in areas of at
least 547 fathoms (1,000 m) depth near a shoreline where there is a
rapid change in bathymetry on the order of 547 to 3,281 fathoms (1,000
to 6,000 m) occurring across a relatively short horizontal distance
(Freitas, 2004). Multiple ships (in this instance, five) were operating
MFAS in the same area over extended periods of time (in this case, 20
hours) in close proximity; and exercises took place in an area
surrounded by landmasses, or in an embayment. Exercises involving
multiple ships employing MFAS near land may have produced sound
directed towards a channel or embayment that may have cut off the lines
of egress for the affected marine mammals (Freitas, 2004).

Behaviorally Mediated Responses to MFAS That May Lead to Stranding

Although the confluence of Navy MFAS with the other contributory
factors noted in the 2001 NMFS/Navy joint report was identified as the
cause of the 2000 Bahamas stranding event, the specific mechanisms that
led to that stranding (or the others) are not well understood, and
there is uncertainty regarding the ordering of effects that led to the
stranding. It is unclear whether beaked whales were directly injured by
sound (e.g., acoustically mediated bubble growth, as addressed above)
prior to stranding or whether a behavioral response to sound occurred
that ultimately caused the beaked whales to be injured and strand.
Although causal relationships between beaked whale stranding events
and active sonar remain unknown, several authors have hypothesized that
stranding events involving these species in the Bahamas and Canary
Islands may have been triggered when the whales changed their dive
behavior in a startled response to exposure to active sonar or to
further avoid exposure (Cox et al., 2006; Rommel et al., 2006). These
authors proposed three mechanisms by which the behavioral responses of
beaked whales upon being exposed to active sonar might result in a
stranding event. These include the following: Gas bubble formation
caused by excessively fast surfacing; remaining at the surface too long
when tissues are supersaturated with nitrogen; or diving prematurely
when extended time at the surface is necessary to eliminate excess
nitrogen. More specifically, beaked whales that occur in deep waters
that are in close proximity to shallow waters (for example, the
``canyon areas'' that are cited in the Bahamas stranding event; see
D'Spain and D'Amico, 2006), may respond to active sonar by swimming
into shallow waters to avoid further exposures and strand if they were
not able to swim back to deeper waters. Second, beaked whales exposed
to active sonar might alter their dive behavior. Changes in their dive
behavior might cause them to remain at the surface or at depth for
extended periods

[[Page 33959]]

of time which could lead to hypoxia directly by increasing their oxygen
demands or indirectly by increasing their energy expenditures (to
remain at depth) and increase their oxygen demands as a result. If
beaked whales are at depth when they detect a ping from an active sonar
transmission and change their dive profile, this could lead to the
formation of significant gas bubbles, which could damage multiple
organs or interfere with normal physiological function (Cox et al.,
2006; Rommel et al., 2006; Zimmer and Tyack, 2007). Baird et al. (2005)
found that slow ascent rates from deep dives and long periods of time
spent within 50 m of the surface were typical for both Cuvier's and
Blainville's beaked whales, the two species involved in mass strandings
related to naval sonar. These two behavioral mechanisms may be
necessary to purge excessive dissolved nitrogen concentrated in their
tissues during their frequent long dives (Baird et al., 2005). Baird et
al. (2005) further suggests that abnormally rapid ascents or premature
dives in response to high-intensity sonar could indirectly result in
physical harm to the beaked whales, through the mechanisms described
above (gas bubble formation or non-elimination of excess nitrogen). In
a review of the previously published data on the potential impacts of
sonar on beaked whales, Bernaldo de Quir[oacute]s et al. (2019)
suggested that the effect of mid-frequency active sonar on beaked
whales varies among individuals or populations, and that predisposing
conditions such as previous exposure to sonar and individual health
risk factors may contribute to individual outcomes (such as
decompression sickness).
Because many species of marine mammals make repetitive and
prolonged dives to great depths, it has long been assumed that marine
mammals have evolved physiological mechanisms to protect against the
effects of rapid and repeated decompressions. Although several
investigators have identified physiological adaptations that may
protect marine mammals against nitrogen gas supersaturation (alveolar
collapse and elective circulation; Kooyman et al., 1972; Ridgway and
Howard, 1979), Ridgway and Howard (1979) reported that bottlenose
dolphins that were trained to dive repeatedly had muscle tissues that
were substantially supersaturated with nitrogen gas. Houser et al.
(2001) used these data to model the accumulation of nitrogen gas within
the muscle tissue of other marine mammal species and concluded that
cetaceans that dive deep and have slow ascent or descent speeds would
have tissues that are more supersaturated with nitrogen gas than other
marine mammals. Based on these data, Cox et al. (2006) hypothesized
that a critical dive sequence might make beaked whales more prone to
stranding in response to acoustic exposures. The sequence began with
(1) very deep (to depths as deep as 2 km) and long (as long as 90
minutes) foraging dives; (2) relatively slow, controlled ascents; and
(3) a series of ``bounce'' dives between 100 and 400 m in depth (see
also Zimmer and Tyack, 2007). They concluded that acoustic exposures
that disrupted any part of this dive sequence (for example, causing
beaked whales to spend more time at surface without the bounce dives
that are necessary to recover from the deep dive) could produce
excessive levels of nitrogen supersaturation in their tissues, leading
to gas bubble and emboli formation that produces pathologies similar to
decompression sickness.
Zimmer and Tyack (2007) modeled nitrogen tension and bubble growth
in several tissue compartments for several hypothetical dive profiles
and concluded that repetitive shallow dives (defined as a dive where
depth does not exceed the depth of alveolar collapse, approximately 72
m for Cuvier's beaked whale), perhaps as a consequence of an extended
avoidance reaction to sonar sound, could pose a risk for decompression
sickness and that this risk should increase with the duration of the
response. Their models also suggested that unrealistically rapid rates
of ascent from normal dive behaviors are unlikely to result in
supersaturation to the extent that bubble formation would be expected.
Tyack et al. (2006) suggested that emboli observed in animals exposed
to mid-frequency range sonar (Jepson et al., 2003; Fernandez et al.,
2005; Fern[aacute]ndez et al., 2012) could stem from a behavioral
response that involves repeated dives shallower than the depth of lung
collapse. Given that nitrogen gas accumulation is a passive process
(i.e., nitrogen is metabolically inert), a bottlenose dolphin was
trained to repetitively dive a profile predicted to elevate nitrogen
saturation to the point that nitrogen bubble formation was predicted to
occur. However, inspection of the vascular system of the dolphin via
ultrasound did not demonstrate the formation of asymptomatic nitrogen
gas bubbles (Houser et al., 2007). Baird et al. (2008), in a beaked
whale tagging study off Hawaii, showed that deep dives are equally
common during day or night, but ``bounce dives'' are typically a
daytime behavior, possibly associated with visual predator avoidance.
This may indicate that ``bounce dives'' are associated with something
other than behavioral regulation of dissolved nitrogen levels, which
would be necessary day and night.
If marine mammals respond to a Navy vessel that is transmitting
active sonar in the same way that they might respond to a predator,
their probability of flight responses could increase when they perceive
that Navy vessels are approaching them directly, because a direct
approach may convey detection and intent to capture (Burger and
Gochfeld, 1981, 1990; Cooper, 1997, 1998). The probability of flight
responses could also increase as received levels of active sonar
increase (and the ship is, therefore, closer) and as ship speeds
increase (that is, as approach speeds increase). For example, the
probability of flight responses in Dall's sheep (Ovis dalli dalli)
(Frid 2001a, b), ringed seals (Phoca hispida) (Born et al., 1999),
Pacific brant (Branta bernic nigricans) and Canada geese (B.
canadensis) increased as a helicopter or fixed-wing aircraft approached
groups of these animals more directly (Ward et al., 1999). Bald eagles
(Haliaeetus leucocephalus) perched on trees alongside a river were also
more likely to flee from a paddle raft when their perches were closer
to the river or were closer to the ground (Steidl and Anthony, 1996).
Despite the many theories involving bubble formation (both as a
direct cause of injury, see Acoustically-Induced Bubble Formation Due
to Sonars and Other Pressure-related Injury section and an indirect
cause of stranding), Southall et al. (2007) summarizes that there is
either scientific disagreement or a lack of information regarding each
of the following important points: (1) Received acoustical exposure
conditions for animals involved in stranding events; (2) pathological
interpretation of observed lesions in stranded marine mammals; (3)
acoustic exposure conditions required to induce such physical trauma
directly; (4) whether noise exposure may cause behavioral reactions
(such as atypical diving behavior) that secondarily cause bubble
formation and tissue damage; and (5) the extent the post mortem
artifacts introduced by decomposition before sampling, handling,
freezing, or necropsy procedures affect interpretation of observed
lesions.

Strandings in the NWTT Study Area

Stranded marine mammals are reported along the entire western coast
of the United States each year. Marine mammals strand due to natural or

[[Page 33960]]

anthropogenic causes; the majority of reported type of occurrences in
marine mammal strandings in this region include fishery interactions,
illness, predation, and vessel strikes (Carretta et al., 2017b; Helker
et al., 2017; National Marine Fisheries Service, 2016). Stranding
events that are associated with active UMEs on the Northwest Coast of
the United States (inclusive of the NWTT Study Area) were previously
discussed in the Description of Marine Mammals and Their Habitat in the
Area of the Specified Activities section.
From 2007-2016, 43,125 marine mammal strandings were confirmed by
the West Coast Marine Mammal Stranding Network including 33,569 in
California (including areas outside the NWTT Study Area), 3,776 in
Oregon, and 5,780 in Washington (10 year Data Summary Report, West
Coast Marine Mammal Stranding Network 2017). The most common marine
mammal to strand in the NWTT Study Area was pinnipeds, which comprise
94 percent of strandings in California, 90 percent of strandings in
Oregon, and 89 percent of strandings in Washington. The next most
common group was odontocetes, with harbor porpoises being the most
common species. Gray whales were reported to be the most common large
whale species to strand on the U.S. West Coast in all states. Where
evidence of human interaction can be determined (9 percent as reported
in the 10-year summary), the most common source of interaction on the
U.S. West Coast was fishery interaction for pinnipeds, small cetaceans
and large whales. The Behm Canal portion of the Study Area is a very
small portion of the Southeast Regional Subarea of the Alaska Marine
Mammal Stranding Network. A 10-year summary report is not available in
this region however, in 2019 there were 40 confirmed strandings in the
entire Southeast Regional Subarea, and 30 of these strandings were
harbor seals or Steller sea lions.
One stranding event has been investigated for a possible link to
Navy activities in the NWTT Study Area. Between May 2 and June 2, 2003,
approximately 16 strandings involving 15 harbor porpoises and one
Dall's porpoise in the Eastern Strait of Juan de Fuca and Haro Strait
were reported to the Northwest Marine Mammal Stranding Network. Given
that the USS SHOUP was known to have operated sonar in the Haro strait
on May 5, 2003, and that behavioral reactions of killer whales were
possibly linked to these sonar operations, NMFS undertook an analysis
of whether sonar caused the strandings of the porpoises (National
Marine Fisheries Service, 2005). NMFS determined that the 2003
strandings and similar harbor porpoise strandings over the following
years were normal given a number of factors as described in Huggins et
al. (2015). The 2015 NWTT FEIS/OEIS includes a comprehensive review of
all strandings and the events involving the USS SHOUP on May 5, 2003.
Additional information on this event is available in the Navy's
Technical Report on Marine Mammal Strandings Associated with U.S. Navy
Sonar Activities (U.S. Department of the Navy, 2017b). In the years
since the SHOUP incident, annual numbers of stranded porpoises have
been comparable (and sometimes higher) and have also shown similar
causes of death (when determinable) to the causes of death noted in the
SHOUP investigation (Huggins et al., 2015).

Marine Mammal Habitat

The Navy's proposed training and testing activities could
potentially affect marine mammal habitat through the introduction of
impacts to the prey species of marine mammals, acoustic habitat (sound
in the water column), water quality, and biologically important habitat
for marine mammals. Each of these potential effects was considered in
the 2019 NWTT DSEIS/OEIS and was determined by the Navy to have no
effect on marine mammal habitat. Based on the information below and the
supporting information included in the 2019 NWTT DSEIS/OEIS, NMFS has
determined that the proposed training and training activities would not
have adverse or long-term impacts on marine mammal habitat.
Effects to Prey
Sound may affect marine mammals through impacts on the abundance,
behavior, or distribution of prey species (e.g., crustaceans,
cephalopods, fish, zooplankton). Marine mammal prey varies by species,
season, and location and, for some species, is not well documented.
Here, we describe studies regarding the effects of noise on known
marine mammal prey.
Fish utilize the soundscape and components of sound in their
environment to perform important functions such as foraging, predator
avoidance, mating, and spawning (e.g., Zelick et al., 1999; Fay, 2009).
The most likely effects on fishes exposed to loud, intermittent, low-
frequency sounds are behavioral responses (i.e., flight or avoidance).
Short duration, sharp sounds (such as pile driving or air guns) can
cause overt or subtle changes in fish behavior and local distribution.
The reaction of fish to acoustic sources depends on the physiological
state of the fish, past exposures, motivation (e.g., feeding, spawning,
migration), and other environmental factors. Key impacts to fishes may
include behavioral responses, hearing damage, barotrauma (pressure-
related injuries), and mortality.
Fishes, like other vertebrates, have a variety of different sensory
systems to glean information from ocean around them (Astrup and Mohl,
1993; Astrup, 1999; Braun and Grande, 2008; Carroll et al., 2017;
Hawkins and Johnstone, 1978; Ladich and Popper, 2004; Ladich and
Schulz-Mirbach, 2016; Mann, 2016; Nedwell et al., 2004; Popper et al.,
2003; Popper et al., 2005). Depending on their hearing anatomy and
peripheral sensory structures, which vary among species, fishes hear
sounds using pressure and particle motion sensitivity capabilities and
detect the motion of surrounding water (Fay et al., 2008) (terrestrial
vertebrates generally only detect pressure). Most marine fishes
primarily detect particle motion using the inner ear and lateral line
system, while some fishes possess additional morphological adaptations
or specializations that can enhance their sensitivity to sound
pressure, such as a gas-filled swim bladder (Braun and Grande, 2008;
Popper and Fay, 2011).
Hearing capabilities vary considerably between different fish
species with data only available for just over 100 species out of the
34,000 marine and freshwater fish species (Eschmeyer and Fong, 2016).
In order to better understand acoustic impacts on fishes, fish hearing
groups are defined by species that possess a similar continuum of
anatomical features which result in varying degrees of hearing
sensitivity (Popper and Hastings, 2009a). There are four hearing groups
defined for all fish species (modified from Popper et al., 2014) within
this analysis and they include: Fishes without a swim bladder (e.g.,
flatfish, sharks, rays, etc.); fishes with a swim bladder not involved
in hearing (e.g., salmon, cod, pollock, etc.); fishes with a swim
bladder involved in hearing (e.g., sardines, anchovy, herring, etc.);
and fishes with a swim bladder involved in hearing and high-frequency
hearing (e.g., shad and menhaden). Most marine mammal fish prey species
would not be likely to perceive or hear Navy mid- or high-frequency
sonars. While hearing studies have not been done on sardines and
northern anchovies, it would not be unexpected for them to possess
hearing similarities to Pacific herring (up to 2-5 kHz) (Mann et al.,
2005). Currently, less data are available to estimate the range of best
sensitivity for fishes without a swim bladder.

[[Page 33961]]

In terms of physiology, multiple scientific studies have documented
a lack of mortality or physiological effects to fish from exposure to
low- and mid-frequency sonar and other sounds (Halvorsen et al., 2012;
J[oslash]rgensen et al., 2005; Juanes et al., 2017; Kane et al., 2010;
Kvadsheim and Sevaldsen, 2005; Popper et al., 2007; Popper et al.,
2016; Watwood et al., 2016). Techer et al. (2017) exposed carp in
floating cages for up to 30 days to low-power 23 and 46 kHz sources
without any significant physiological response. Other studies have
documented either a lack of TTS in species whose hearing range cannot
perceive Navy sonar, or for those species that could perceive sonar-
like signals, any TTS experienced would be recoverable (Halvorsen et
al., 2012; Ladich and Fay, 2013; Popper and Hastings, 2009a, 2009b;
Popper et al., 2014; Smith, 2016). Only fishes that have
specializations that enable them to hear sounds above about 2,500 Hz
(2.5 kHz) such as herring (Halvorsen et al., 2012; Mann et al., 2005;
Mann, 2016; Popper et al., 2014) would have the potential to receive
TTS or exhibit behavioral responses from exposure to mid-frequency
sonar. In addition, any sonar induced TTS to fish whose hearing range
could perceive sonar would only occur in the narrow spectrum of the
source (e.g., 3.5 kHz) compared to the fish's total hearing range
(e.g., 0.01 kHz to 5 kHz). Overall, Navy sonar sources are much
narrower in terms of source frequency compared to a given fish species
full hearing range (Halvorsen et al., 2012; J[oslash]rgensen et al.,
2005; Juanes et al., 2017; Kane et al., 2010; Kvadsheim & Sevaldsen,
2005; Popper et al., 2007; Popper and Hawkins, 2016; Watwood et al.,
2016).
In terms of behavioral responses, Juanes et al. (2017) discuss the
potential for negative impacts from anthropogenic soundscapes on fish,
but the author's focus was on broader based sounds such as ship and
boat noise sources. Watwood et al. (2016) also documented no behavioral
responses by reef fish after exposure to mid-frequency active sonar.
Doksaeter et al. (2009; 2012) reported no behavioral responses to mid-
frequency naval sonar by Atlantic herring; specifically, no escape
reactions (vertically or horizontally) were observed in free swimming
herring exposed to mid-frequency sonar transmissions. Based on these
results (Doksaeter et al., 2009; Doksaeter et al., 2012; Sivle et al.,
2012), Sivle et al. (2014) created a model in order to report on the
possible population-level effects on Atlantic herring from active naval
sonar. The authors concluded that the use of naval sonar poses little
risk to populations of herring regardless of season, even when the
herring populations are aggregated and directly exposed to sonar.
Finally, Bruintjes et al. (2016) commented that fish exposed to any
short-term noise within their hearing range might initially startle,
but would quickly return to normal behavior.
Occasional behavioral reactions to intermittent explosions and
impulsive sound sources are unlikely to cause long-term consequences
for individual fish or populations. Fish that experience hearing loss
as a result of exposure to explosions and impulsive sound sources may
have a reduced ability to detect relevant sounds such as predators,
prey, or social vocalizations. However, PTS has not been known to occur
in fishes and any hearing loss in fish may be as temporary as the
timeframe required to repair or replace the sensory cells that were
damaged or destroyed (Popper et al., 2005; Popper et al., 2014; Smith
et al., 2006). It is not known if damage to auditory nerve fibers could
occur, and if so, whether fibers would recover during this process. It
is also possible for fish to be injured or killed by an explosion in
the immediate vicinity of the surface from dropped or fired ordnance,
or near the bottom from shallow water bottom-placed underwater mine
warfare detonations. Physical effects from pressure waves generated by
underwater sounds (e.g., underwater explosions) could potentially
affect fish within proximity of training or testing activities. SPLs of
sufficient strength have been known to cause injury to fish and fish
mortality (summarized in Popper et al., 2014). The shock wave from an
underwater explosion is lethal to fish at close range, causing massive
organ and tissue damage and internal bleeding (Keevin and Hempen,
1997). At greater distance from the detonation point, the extent of
mortality or injury depends on a number of factors including fish size,
body shape, orientation, and species (Keevin and Hempen, 1997; Wright,
1982). At the same distance from the source, larger fish are generally
less susceptible to death or injury, elongated forms that are round in
cross-section are less at risk than deep-bodied forms, and fish
oriented sideways to the blast suffer the greatest impact (Edds-Walton
and Finneran, 2006; O'Keeffe, 1984; O'Keeffe and Young, 1984; Wiley et
al., 1981; Yelverton et al., 1975). Species with gas-filled organs are
more susceptible to injury and mortality than those without them
(Gaspin, 1975; Gaspin et al., 1976; Goertner et al., 1994). Barotrauma
injuries have been documented during controlled exposure to impact pile
driving (an impulsive noise source, as are explosives and air guns)
(Halvorsen et al., 2012b; Casper et al., 2013).
Fish not killed or driven from a location by an explosion might
change their behavior, feeding pattern, or distribution. Changes in
behavior of fish have been observed as a result of sound produced by
explosives, with effect intensified in areas of hard substrate (Wright,
1982). However, Navy explosive use avoids hard substrate to the best
extent practical during underwater detonations, or deep-water surface
detonations. Stunning from pressure waves could also temporarily
immobilize fish, making them more susceptible to predation. The
abundances of various fish (and invertebrates) near the detonation
point for explosives could be altered for a few hours before animals
from surrounding areas repopulate the area. However, these populations
would likely be replenished as waters near the detonation point are
mixed with adjacent waters. Repeated exposure of individual fish to
sounds from underwater explosions is not likely and exposures are
expected to be short-term and localized. Long-term consequences for
fish populations would not be expected.
For fishes exposed to Navy sonar, there would be limited sonar use
spread out in time and space across large offshore areas such that only
small areas are actually ensonified (tens of miles) compared to the
total life history distribution of fish prey species. There would be no
probability for mortality or physical injury from sonar, and for most
species, no or little potential for hearing or behavioral effects,
except to a few select fishes with hearing specializations (e.g.,
herring) that could perceive mid-frequency sonar. Training and testing
exercises involving explosions are dispersed in space and time;
therefore, repeated exposure of individual fishes are unlikely.
Mortality and injury effects to fishes from explosives would be
localized around the area of a given in-water explosion, but only if
individual fish and the explosive (and immediate pressure field) were
co-located at the same time. Fishes deeper in the water column or on
the bottom would not be affected by water surface explosions. Repeated
exposure of individual fish to sound and energy from underwater
explosions is not likely given fish movement patterns, especially
schooling prey species. Most acoustic effects, if any, are expected to
be short-term and localized.

[[Page 33962]]

Long-term consequences for fish populations, including key prey species
within the NWTT Study Area, would not be expected.
Vessels and in-water devices do not normally collide with adult
fish, most of which can detect and avoid them. Exposure of fishes to
vessel strike stressors is limited to those fish groups that are large,
slow-moving, and may occur near the surface, such as ocean sunfish,
whale sharks, basking sharks, and manta rays. These species are
distributed widely in offshore portions of the NWTT Study Area. Any
isolated cases of a Navy vessel striking an individual could injure
that individual, impacting the fitness of an individual fish. Vessel
strikes would not pose a risk to most of the other marine fish groups,
because many fish can detect and avoid vessel movements, making strikes
rare and allowing the fish to return to their normal behavior after the
ship or device passes. As a vessel approaches a fish, they could have a
detectable behavioral or physiological response (e.g., swimming away
and increased heart rate) as the passing vessel displaces them.
However, such reactions are not expected to have lasting effects on the
survival, growth, recruitment, or reproduction of these marine fish
groups at the population level and therefore would not have an impact
on marine mammal species as prey items.
In addition to fish, prey sources such as marine invertebrates
could potentially be impacted by sound stressors as a result of the
proposed activities. However, most marine invertebrates' ability to
sense sounds is very limited. In most cases, marine invertebrates would
not respond to impulsive and non-impulsive sounds, although they may
detect and briefly respond to nearby low-frequency sounds. These short-
term responses would likely be inconsequential to invertebrate
populations.
Invertebrates appear to be able to detect sounds (Pumphrey, 1950;
Frings and Frings, 1967) and are most sensitive to low-frequency sounds
(Packard et al., 1990; Budelmann and Williamson, 1994; Lovell et al.,
2005; Mooney et al., 2010). Data on response of invertebrates such as
squid, another marine mammal prey species, to anthropogenic sound is
more limited (de Soto, 2016; Sole et al., 2017b). Data suggest that
cephalopods are capable of sensing the particle motion of sounds and
detect low frequencies up to 1-1.5 kHz, depending on the species, and
so are likely to detect air gun noise (Kaifu et al., 2008; Hu et al.,
2009; Mooney et al., 2010; Samson et al., 2014). Sole et al. (2017b)
reported physiological injuries to cuttlefish in cages placed at-sea
when exposed during a controlled exposure experiment to low-frequency
sources (315 Hz, 139 to 142 dB re: 1 [mu]Pa\2\ and 400 Hz, 139 to 141
dB re: 1 [mu]Pa\2\). Fewtrell and McCauley (2012) reported squids
maintained in cages displayed startle responses and behavioral changes
when exposed to seismic air gun sonar (136-162 re: 1
[mu]Pa\2\[middot]s). However, the sources Sole et al. (2017a) and
Fewtrell and McCauley (2012) used are not similar and were much lower
than typical Navy sources within the NWTT Study Area. Nor do the
studies address the issue of individual displacement outside of a zone
of impact when exposed to sound. Cephalopods have a specialized sensory
organ inside the head called a statocyst that may help an animal
determine its position in space (orientation) and maintain balance
(Budelmann, 1992). Packard et al. (1990) showed that cephalopods were
sensitive to particle motion, not sound pressure, and Mooney et al.
(2010) demonstrated that squid statocysts act as an accelerometer
through which particle motion of the sound field can be detected.
Auditory injuries (lesions occurring on the statocyst sensory hair
cells) have been reported upon controlled exposure to low-frequency
sounds, suggesting that cephalopods are particularly sensitive to low-
frequency sound (Andre et al., 2011; Sole et al., 2013). Behavioral
responses, such as inking and jetting, have also been reported upon
exposure to low-frequency sound (McCauley et al., 2000b; Samson et al.,
2014). Squids, like most fish species, are likely more sensitive to low
frequency sounds, and may not perceive mid- and high-frequency sonars
such as Navy sonars. Cumulatively for squid as a prey species,
individual and population impacts from exposure to Navy sonar and
explosives, like fish, are not likely to be significant, and explosive
impacts would be short-term and localized.
Explosions could kill or injure nearby marine invertebrates.
Vessels also have the potential to impact marine invertebrates by
disturbing the water column or sediments, or directly striking
organisms (Bishop, 2008). The propeller wash (water displaced by
propellers used for propulsion) from vessel movement and water
displaced from vessel hulls can potentially disturb marine
invertebrates in the water column and is a likely cause of zooplankton
mortality (Bickel et al., 2011). The localized and short-term exposure
to explosions or vessels could displace, injure, or kill zooplankton,
invertebrate eggs or larvae, and macro-invertebrates. However,
mortality or long-term consequences for a few animals is unlikely to
have measurable effects on overall populations. Long-term consequences
to marine invertebrate populations would not be expected as a result of
exposure to sounds of vessels in the NWTT Study Area.
Impacts to benthic communities from impulsive sound generated by
active acoustic sound sources are not well documented. (e.g.,
Andriguetto-Filho et al., 2005; Payne et al., 2007; 2008; Boudreau et
al., 2009). There are no published data that indicate whether temporary
or permanent threshold shifts, auditory masking, or behavioral effects
occur in benthic invertebrates (Hawkins et al., 2014) and some studies
showed no short-term or long-term effects of air gun exposure (e.g.,
Andriguetto-Filho et al., 2005; Payne et al., 2007; 2008; Boudreau et
al., 2009). Exposure to air gun signals was found to significantly
increase mortality in scallops, in addition to causing significant
changes in behavioral patterns during exposure (Day et al., 2017).
However, the authors state that the observed levels of mortality were
not beyond naturally occurring rates. Explosions and pile driving could
potentially kill or injure nearby marine invertebrates; however,
mortality or long-term consequences for a few animals is unlikely to
have measurable effects on overall populations.
There is little information concerning potential impacts of noise
on zooplankton populations. However, one recent study (McCauley et al.,
2017) investigated zooplankton abundance, diversity, and mortality
before and after exposure to air gun noise, finding that the mortality
rate for zooplankton after airgun exposure was two to three times more
compared with controls for all taxa. The majority of taxa present were
copepods and cladocerans; for these taxa, the range within which
effects on abundance were detected was up to approximately 1.2 km. In
order to have significant impacts on r-selected species such as
plankton, the spatial or temporal scale of impact must be large in
comparison with the ecosystem concerned (McCauley et al., 2017).
Therefore, the large scale of effect observed here is of concern--
particularly where repeated noise exposure is expected--and further
study is warranted.
Military expended materials resulting from training and testing
activities could potentially result in minor long-term changes to
benthic habitat, however the impacts of small amount of expended
materials are unlikely to have

[[Page 33963]]

measurable effects on overall populations. Military expended materials
may be colonized over time by benthic organisms that prefer hard
substrate and would provide structure that could attract some species
of fish or invertebrates.
Overall, the combined impacts of sound exposure, explosions, vessel
strikes, and military expended materials resulting from the proposed
activities would not be expected to have measurable effects on
populations of marine mammal prey species. Prey species exposed to
sound might move away from the sound source, experience TTS, experience
masking of biologically relevant sounds, or show no obvious direct
effects. Mortality from decompression injuries is possible in close
proximity to a sound, but only limited data on mortality in response to
air gun noise exposure are available (Hawkins et al., 2014). The most
likely impacts for most prey species in a given area would be temporary
avoidance of the area. Surveys using towed air gun arrays move through
an area relatively quickly, limiting exposure to multiple impulsive
sounds. In all cases, sound levels would return to ambient once a
survey ends and the noise source is shut down and, when exposure to
sound ends, behavioral and/or physiological responses are expected to
end relatively quickly (McCauley et al., 2000b). The duration of fish
avoidance of a given area after survey effort stops is unknown, but a
rapid return to normal recruitment, distribution, and behavior is
anticipated. While the potential for disruption of spawning
aggregations or schools of important prey species can be meaningful on
a local scale, the mobile and temporary nature of most surveys and the
likelihood of temporary avoidance behavior suggest that impacts would
be minor. Long-term consequences to marine invertebrate populations
would not be expected as a result of exposure to sounds or vessels in
the NWTT Study Area.
Acoustic Habitat
Acoustic habitat is the soundscape which encompasses all of the
sound present in a particular location and time, as a whole when
considered from the perspective of the animals experiencing it. Animals
produce sound for, or listen for sounds produced by, conspecifics
(communication during feeding, mating, and other social activities),
other animals (finding prey or avoiding predators), and the physical
environment (finding suitable habitats, navigating). Together, sounds
made by animals and the geophysical environment (e.g., produced by
earthquakes, lightning, wind, rain, waves) make up the natural
contributions to the total acoustics of a place. These acoustic
conditions, termed acoustic habitat, are one attribute of an animal's
total habitat.
Soundscapes are also defined by, and acoustic habitat influenced
by, the total contribution of anthropogenic sound. This may include
incidental emissions from sources such as vessel traffic or may be
intentionally introduced to the marine environment for data acquisition
purposes (as in the use of air gun arrays) or for Navy training and
testing purposes (as in the use of sonar and explosives and other
acoustic sources). Anthropogenic noise varies widely in its frequency,
content, duration, and loudness, and these characteristics greatly
influence the potential habitat-mediated effects to marine mammals
(please also see the previous discussion on ``Masking''), which may
range from local effects for brief periods of time to chronic effects
over large areas and for long durations. Depending on the extent of
effects to habitat, animals may alter their communications signals
(thereby potentially expending additional energy) or miss acoustic cues
(either conspecific or adventitious). Problems arising from a failure
to detect cues are more likely to occur when noise stimuli are chronic
and overlap with biologically relevant cues used for communication,
orientation, and predator/prey detection (Francis and Barber, 2013).
For more detail on these concepts see, e.g., Barber et al., 2009;
Pijanowski et al., 2011; Francis and Barber, 2013; Lillis et al., 2014.
The term ``listening area'' refers to the region of ocean over
which sources of sound can be detected by an animal at the center of
the space. Loss of communication space concerns the area over which a
specific animal signal (used to communicate with conspecifics in
biologically important contexts such as foraging or mating) can be
heard, in noisier relative to quieter conditions (Clark et al., 2009).
Lost listening area concerns the more generalized contraction of the
range over which animals would be able to detect a variety of signals
of biological importance, including eavesdropping on predators and prey
(Barber et al., 2009). Such metrics do not, in and of themselves,
document fitness consequences for the marine animals that live in
chronically noisy environments. Long-term population-level consequences
mediated through changes in the ultimate survival and reproductive
success of individuals are difficult to study, and particularly so
underwater. However, it is increasingly well documented that aquatic
species rely on qualities of natural acoustic habitats, with
researchers quantifying reduced detection of important ecological cues
(e.g., Francis and Barber, 2013; Slabbekoorn et al., 2010) as well as
survivorship consequences in several species (e.g., Simpson et al.,
2014; Nedelec et al., 2015).
The sounds produced during training and testing activities can be
widely dispersed or concentrated in small areas for varying periods.
Sound produced from training and testing activities in the NWTT Study
Area is temporary and transitory. Any anthropogenic noise attributed to
training and testing activities in the NWTT Study Area would be
temporary and the affected area would be expected to immediately return
to the original state when these activities cease.
Water Quality
Training and testing activities may introduce water quality
constituents into the water column. Based on the analysis of the 2019
NWTT DSEIS/OEIS, military expended materials (e.g., undetonated
explosive materials) would be released in quantities and at rates that
would not result in a violation of any water quality standard or
criteria. NMFS has reviewed this analysis and concurs that it reflects
the best available science. High-order explosions consume most of the
explosive material, creating typical combustion products. For example,
in the case of Royal Demolition Explosive, 98 percent of the products
are common seawater constituents and the remainder is rapidly diluted
below threshold effect level. Explosion by-products associated with
high order detonations present no secondary stressors to marine mammals
through sediment or water. However, low order detonations and
unexploded ordnance present elevated likelihood of impacts on marine
mammals.
Indirect effects of explosives and unexploded ordnance to marine
mammals via sediment is possible in the immediate vicinity of the
ordnance. Degradation products of Royal Demolition Explosive are not
toxic to marine organisms at realistic exposure levels (Rosen and
Lotufo, 2010). Relatively low solubility of most explosives and their
degradation products means that concentrations of these contaminants in
the marine environment are relatively low and readily diluted.
Furthermore, while explosives and their degradation products were
detectable in marine sediment approximately 6-12 in (0.15-0.3 m) away
from degrading ordnance, the concentrations of these compounds

[[Page 33964]]

were not statistically distinguishable from background beyond 3-6 ft
(1-2 m) from the degrading ordnance. Taken together, it is possible
that marine mammals could be exposed to degrading explosives, but it
would be within a very small radius of the explosive (1-6 ft (0.3-2
m)).
Equipment used by the Navy within the NWTT Study Area, including
ships and other marine vessels, aircraft, and other equipment, are also
potential sources of by-products. All equipment is properly maintained
in accordance with applicable Navy and legal requirements. All such
operating equipment meets Federal water quality standards, where
applicable.

Estimated Take of Marine Mammals

This section indicates the number of takes that NMFS is proposing
to authorize, which is based on the amount of take that NMFS
anticipates could occur or the maximum amount that is reasonably likely
to occur, depending on the type of take and the methods used to
estimate it, as described in detail below. NMFS coordinated closely
with the Navy in the development of their incidental take application,
and preliminarily agrees that the methods the Navy has put forth
described herein to estimate take (including the model, thresholds, and
density estimates), and the resulting numbers estimated for
authorization, are appropriate and based on the best available science.
Takes would be predominantly in the form of harassment, but a small
number of mortalities are also possible. For a military readiness
activity, the MMPA defines ``harassment'' as (i) Any act that injures
or has the significant potential to injure a marine mammal or marine
mammal stock in the wild (Level A Harassment); or (ii) Any act that
disturbs or is likely to disturb a marine mammal or marine mammal stock
in the wild by causing disruption of natural behavioral patterns,
including, but not limited to, migration, surfacing, nursing, breeding,
feeding, or sheltering, to a point where such behavioral patterns are
abandoned or significantly altered (Level B Harassment).
Proposed authorized takes would primarily be in the form of Level B
harassment, as use of the acoustic and explosive sources (i.e., sonar
and explosives) is most likely to result in the disruption of natural
behavioral patterns to a point where they are abandoned or
significantly altered (as defined specifically at the beginning of this
section, but referred to generally as behavioral disruption) or TTS for
marine mammals. There is also the potential for Level A harassment, in
the form of auditory injury to result from exposure to the sound
sources utilized in training and testing activities. Lastly, no more
than three serious injuries or mortalities total (over the seven-year
period) of large whales could potentially occur through vessel
collisions. Although we analyze the impacts of these potential serious
injuries or mortalities that are proposed for authorization, the
proposed mitigation and monitoring measures are expected to minimize
the likelihood (i.e., further lower the already low probability) that
ship strike (and the associated serious injury or mortality) would
occur.
Generally speaking, for acoustic impacts NMFS estimates the amount
and type of harassment by considering: (1) Acoustic thresholds above
which NMFS believes the best available science indicates marine mammals
will be taken by Level B harassment (in this case, as defined in the
military readiness definition of Level B harassment included above) or
incur some degree of temporary or permanent hearing impairment; (2) the
area or volume of water that will be ensonified above these levels in a
day or event; (3) the density or occurrence of marine mammals within
these ensonified areas; and (4) the number of days of activities or
events.

Acoustic Thresholds

Using the best available science, NMFS, in coordination with the
Navy, has established acoustic thresholds that identify the most
appropriate received level of underwater sound above which marine
mammals exposed to these sound sources could be reasonably expected to
experience a disruption in behavior patterns to a point where they are
abandoned or significantly altered, or to incur TTS (equated to Level B
harassment) or PTS of some degree (equated to Level A harassment).
Thresholds have also been developed to identify the pressure levels
above which animals may incur non-auditory injury from exposure to
pressure waves from explosive detonation.
Despite the quickly evolving science, there are still challenges in
quantifying expected behavioral responses that qualify as take by Level
B harassment, especially where the goal is to use one or two
predictable indicators (e.g., received level and distance) to predict
responses that are also driven by additional factors that cannot be
easily incorporated into the thresholds (e.g., context). So, while the
behavioral Level B harassment thresholds have been refined to better
consider the best available science (e.g., incorporating both received
level and distance), they also still have some built-in conservative
factors to address the challenge noted. For example, while duration of
observed responses in the data are now considered in the thresholds,
some of the responses that are informing take thresholds are of a very
short duration, such that it is possible some of these responses might
not always rise to the level of disrupting behavior patterns to a point
where they are abandoned or significantly altered. We describe the
application of this Level B harassment threshold as identifying the
maximum number of instances in which marine mammals could be reasonably
expected to experience a disruption in behavior patterns to a point
where they are abandoned or significantly altered. In summary, we
believe these behavioral Level B harassment thresholds are the most
appropriate method for predicting behavioral Level B harassment given
the best available science and the associated uncertainty.
Hearing Impairment (TTS/PTS) and Tissue Damage and Mortality
NMFS' Acoustic Technical Guidance (NMFS, 2018) identifies dual
criteria to assess auditory injury (Level A harassment) to five
different marine mammal groups (based on hearing sensitivity) as a
result of exposure to noise from two different types of sources
(impulsive or non-impulsive). The Acoustic Technical Guidance also
identifies criteria to predict TTS, which is not considered injury and
falls into the Level B harassment category. The Navy's planned activity
includes the use of non-impulsive (sonar) and impulsive (explosives)
sources.
These thresholds (Tables 10 and 11) were developed by compiling and
synthesizing the best available science and soliciting input multiple
times from both the public and peer reviewers. The references,
analysis, and methodology used in the development of the thresholds are
described in Acoustic Technical Guidance, which may be accessed at:
https://www.fisheries.noaa.gov/national/marine-mammal-protection/
marine-mammal-acoustic-technical-guidance.

[[Page 33965]]

Table 10--Acoustic Thresholds Identifying the Onset of TTS and PTS for
Non-Impulsive Sound Sources by Functional Hearing Groups
------------------------------------------------------------------------
Non-impulsive
-------------------------------------
Functional hearing group TTS threshold SEL PTS threshold SEL
(weighted) (weighted)
------------------------------------------------------------------------
Low-Frequency Cetaceans........... 179 199
Mid-Frequency Cetaceans........... 178 198
High-Frequency Cetaceans.......... 153 173
Phocid Pinnipeds (Underwater)..... 181 201
Otarid Pinnipeds (Underwater)..... 199 219
------------------------------------------------------------------------
Note: SEL thresholds in dB re: 1 [mu]Pa\2\s.

Based on the best available science, the Navy (in coordination with
NMFS) used the acoustic and pressure thresholds indicated in Table 11
to predict the onset of TTS, PTS, tissue damage, and mortality for
explosives (impulsive) and other impulsive sound sources.

Table 11--Onset of TTS, PTS, Tissue Damage, and Mortality thresholds for Marine Mammals for Explosives
--------------------------------------------------------------------------------------------------------------------------------------------------------
Weighted onset Weighted onset Mean onset slight Mean onset slight Mean onset
Functional hearing group Species TTS \1\ PTS GI tract injury lung injury mortality
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency cetaceans......... All mysticetes.... 168 dB SEL or 213 183 dB SEL or 219 237 dB Peak SPL... Equation 1........ Equation 2.
dB Peak SPL. dB Peak SPL.
Mid-frequency cetaceans......... Most delphinids, 170 dB SEL or 224 185 dB SEL or 230 237 dB Peak SPL...
medium and large dB Peak SPL. dB Peak SPL.
toothed whales.
High-frequency cetaceans........ Porpoises and 140 dB SEL or 196 155 dB SEL or 202 237 dB Peak SPL...
Kogia spp. dB Peak SPL. dB Peak SPL.
Phocidae........................ Harbor seal, 170 dB SEL or 212 185 dB SEL or 218 237 dB Peak SPL...
Hawaiian monk dB Peak SPL. dB Peak SPL.
seal, Northern
elephant seal.
Otariidae....................... California sea 188 dB SEL or 226 203 dB SEL or 232 237 dB Peak SPL...
lion, Guadalupe dB Peak SPL. dB Peak SPL.
fur seal,
Northern fur seal.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
Equation 1: 47.5M1/3 (1+[DRm/10.1])1/6 Pa-sec.
Equation 2: 103M1/3 (1+[DRm/10.1])1/6 Pa-sec.
M = mass of the animals in kg.
DRm = depth of the receiver (animal) in meters.
SPL = sound pressure level.
\1\ Peak thresholds are unweighted.

The criteria used to assess the onset of TTS and PTS due to
exposure to sonars (non-impulsive, see Table 10 above) are discussed
further in the Navy's rulemaking/LOA application (see Hearing Loss from
Sonar and Other Transducers in Chapter 6, Section 6.4.2.1, Methods for
Analyzing Impacts from Sonars and Other Transducers). Refer to the
``Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects
Analysis (Phase III)'' report (U.S. Department of the Navy, 2017c) for
detailed information on how the criteria and thresholds were derived.
Non-auditory injury (i.e., other than PTS) and mortality from sonar and
other transducers is so unlikely as to be discountable under normal
conditions for the reasons explained under the Potential Effects of
Specified Activities on Marine Mammals and Their Habitat section--
Acoustically Mediated Bubble Growth and other Pressure-related Injury
and is therefore not considered further in this analysis.
Behavioral Harassment
Though significantly driven by received level, the onset of Level B
harassment by behavioral disturbance from anthropogenic noise exposure
is also informed to varying degrees by other factors related to the
source (e.g., frequency, predictability, duty cycle), the environment
(e.g., bathymetry), and the receiving animals (hearing, motivation,
experience, demography, behavioral context) and can be difficult to
predict (Ellison et al., 2011; Southall et al., 2007). Based on what
the available science indicates and the practical need to use
thresholds based on a factor, or factors, that are both predictable and
measurable for most activities, NMFS uses generalized acoustic
thresholds based primarily on received level (and distance in some
cases) to estimate the onset of Level B behavioral harassment.

Sonar

As noted above, the Navy coordinated with NMFS to develop Level B
behavioral harassment thresholds specific to their military readiness
activities utilizing active sonar. These behavioral response thresholds
are used to estimate the number of animals that

[[Page 33966]]

may exhibit a behavioral response that rises to the level of a take
when exposed to sonar and other transducers. The way the criteria were
derived is discussed in detail in the ``Criteria and Thresholds for
U.S. Navy Acoustic and Explosive Effects Analysis (Phase III)'' report
(U.S. Department of the Navy, 2017c). Developing the Level B harassment
behavioral criteria involved multiple steps. All peer-reviewed
published behavioral response studies conducted both in the field and
on captive animals were examined in order to understand the breadth of
behavioral responses of marine mammals to sonar and other transducers.
NMFS has carefully reviewed the Navy's Level B behavioral thresholds
and establishment of cutoff distances for the species, and agrees that
it is the best available science and is the appropriate method to use
at this time for determining impacts to marine mammals from sonar and
other transducers and for calculating take and to support the
determinations made in this proposed rule.
As discussed above, marine mammal responses to sound (some of which
are considered disturbances that rise to the level of a take) are
highly variable and context specific, i.e., they are affected by
differences in acoustic conditions; differences between species and
populations; differences in gender, age, reproductive status, or social
behavior; and other prior experience of the individuals. This means
that there is support for considering alternative approaches for
estimating Level B behavioral harassment. Although the statutory
definition of Level B harassment for military readiness activities
means that a natural behavior pattern of a marine mammal is
significantly altered or abandoned, the current state of science for
determining those thresholds is somewhat unsettled.
In its analysis of impacts associated with sonar acoustic sources
(which was coordinated with NMFS), the Navy used an updated
conservative approach that likely overestimates the number of takes by
Level B harassment due to behavioral disturbance and response. Many of
the behavioral responses identified using the Navy's quantitative
analysis are most likely to be of moderate severity as described in the
Southall et al. (2007) behavioral response severity scale. These
``moderate'' severity responses were considered significant if they
were sustained for the duration of the exposure or longer. Within the
Navy's quantitative analysis, many reactions are predicted from
exposure to sound that may exceed an animal's Level B behavioral
harassment threshold for only a single exposure (a few seconds) to
several minutes, and it is likely that some of the resulting estimated
behavioral responses that are counted as Level B harassment would not
constitute ``significantly altering or abandoning natural behavioral
patterns.'' The Navy and NMFS have used the best available science to
address the challenging differentiation between significant and non-
significant behavioral reactions (i.e., whether the behavior has been
abandoned or significantly altered such that it qualifies as
harassment), but have erred on the cautious side where uncertainty
exists (e.g., counting these lower duration reactions as take), which
likely results in some degree of overestimation of behavioral Level B
harassment. We consider application of this behavioral Level B
harassment threshold, therefore, as identifying the maximum number of
instances in which marine mammals could be reasonably expected to
experience a disruption in behavior patterns to a point where they are
abandoned or significantly altered (i.e., Level B harassment). Because
this is the most appropriate method for estimating Level B harassment
given the best available science and uncertainty on the topic, it is
these numbers of Level B harassment by behavioral disturbance that are
analyzed in the Preliminary Analysis and Negligible Impact
Determination section and would be authorized.
In the Navy's acoustic impact analyses during Phase II (the
previous phase of Navy testing and training, 2013-2018, see also Navy's
``Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects
Analysis Technical Report'', 2012), the likelihood of behavioral Level
B harassment in response to sonar and other transducers was based on a
probabilistic function (termed a behavioral response function--BRF),
that related the likelihood (i.e., probability) of a behavioral
response (at the level of a Level B harassment) to the received SPL.
The BRF was used to estimate the percentage of an exposed population
that is likely to exhibit Level B harassment due to altered behaviors
or behavioral disturbance at a given received SPL. This BRF relied on
the assumption that sound poses a negligible risk to marine mammals if
they are exposed to SPL below a certain ``basement'' value. Above the
basement exposure SPL, the probability of a response increased with
increasing SPL. Two BRFs were used in Navy acoustic impact analyses:
BRF1 for mysticetes and BRF2 for other species. BRFs were not used for
beaked whales during Phase II analyses. Instead, a step function at an
SPL of 140 dB re: 1 [mu]Pa was used for beaked whales as the threshold
to predict Level B harassment by behavioral disturbance.
Developing the behavioral Level B harassment criteria for Phase III
(the current phase of Navy training and testing activities) involved
multiple steps: all available behavioral response studies conducted
both in the field and on captive animals were examined to understand
the breadth of behavioral responses of marine mammals to sonar and
other transducers (See also Navy's ``Criteria and Thresholds for U.S.
Navy Acoustic and Explosive Effects Analysis (Phase III) Technical
Report'', 2017). Six behavioral response field studies with
observations of 14 different marine mammal species reactions to sonar
or sonar-like signals and 6 captive animal behavioral studies with
observations of 8 different species reactions to sonar or sonar-like
signals were used to provide a robust data set for the derivation of
the Navy's Phase III marine mammal behavioral response criteria. All
behavioral response research that has been published since the
derivation of the Navy's Phase III criteria (c.a. December 2016) has
been examined and is consistent with the current behavioral response
functions. Marine mammal species were placed into behavioral criteria
groups based on their known or suspected behavioral sensitivities to
sound. In most cases these divisions were driven by taxonomic
classifications (e.g., mysticetes, pinnipeds). The data from the
behavioral studies were analyzed by looking for significant responses,
or lack thereof, for each experimental session.
The Navy used cutoff distances beyond which the potential of
significant behavioral responses (and therefore Level B harassment) is
considered to be unlikely (see Table 12 below). These distances were
determined by examining all available published field observations of
behavioral reactions to sonar or sonar-like signals that included the
distance between the sound source and the marine mammal. The longest
distance, rounded up to the nearest 5-km increment, was chosen as the
cutoff distance for each behavioral criteria group (i.e. odontocetes,
mysticetes, and beaked whales). For animals within the cutoff distance,
behavioral response functions for each behavioral criteria group based
on a received SPL as presented in Chapter 6, Section 6.4.2.1 (Methods
for Analyzing Impacts from Sonars and other Transducers) of the Navy's
rulemaking/LOA application were used to predict the probability of

[[Page 33967]]

a potential significant behavioral response. For training and testing
events that contain multiple platforms or tactical sonar sources that
exceed 215 dB re: 1 [mu]Pa at 1 m, this cutoff distance is
substantially increased (i.e., doubled) from values derived from the
literature. The use of multiple platforms and intense sound sources are
factors that probably increase responsiveness in marine mammals overall
(however, we note that helicopter dipping sonars were considered in the
intense sound source group, despite lower source levels, because of
data indicating that marine mammals are sometimes more responsive to
the less predictable employment of this source). There are currently
few behavioral observations under these circumstances; therefore, the
Navy conservatively predicted significant behavioral responses that
would rise to Level B harassment at farther ranges than shown in Table
12, versus less intense events.

Table 12--Cutoff Distances for Moderate Source Level, Single Platform
Training and Testing Events and for All Other Events With Multiple
Platforms or Sonar With Source Levels at or Exceeding 215 dB re: 1
[micro]Pa at 1 m.
------------------------------------------------------------------------
Moderate SL/
single High SL/multi-
Criteria group platform platform
cutoff cutoff
distance (km) distance (km)
------------------------------------------------------------------------
Odontocetes............................. 10 20
Pinnipeds............................... 5 10
Mysticetes.............................. 10 20
Beaked Whales........................... 25 50
Harbor Porpoise......................... 20 40
------------------------------------------------------------------------
Notes: dB re: 1 [mu]Pa at 1 m = decibels referenced to 1 micropascal at
1 meter, km = kilometer, SL = source level.

The range to received sound levels in 6-dB steps from five
representative sonar bins and the percentage of animals that may be
taken by Level B harassment under each behavioral response function are
shown in Tables 13 through 17. Cells are shaded if the mean range value
for the specified received level exceeds the distance cutoff range for
a particular hearing group and therefore are not included in the
estimated take. See Chapter 6, Section 6.4.2.1 (Methods for Analyzing
Impacts from Sonars and Other Transducers) of the Navy's rulemaking/LOA
application for further details on the derivation and use of the
behavioral response functions, thresholds, and the cutoff distances to
identify takes by Level B harassment, which were coordinated with NMFS.
As noted previously, NMFS carefully reviewed, and contributed to, the
Navy's proposed behavioral Level B harassment thresholds and cutoff
distances for each behavioral criteria group, and agrees that these
methods represent the best available science at this time for
determining impacts to marine mammals from sonar and other transducers.
Table 13 illustrates the maximum likely percentage of exposed
individuals taken at the indicated received level and associated range
(in which marine mammals would be reasonably expected to experience a
disruption in behavior patterns to a point where they are abandoned or
significantly altered) for low-frequency active sonar (LFAS).
BILLING CODE 3510-22-P

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Tables 14 through 16 identify the maximum likely percentage of
exposed individuals taken at the indicated received level and
associated range for mid-frequency active sonar (MFAS).

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Table 17 identifies the maximum likely percentage of exposed
individuals taken at the indicated received level and associated range
for high-frequency active sonar (HFAS).

[[Page 33972]]

[GRAPHIC] [TIFF OMITTED] TP02JN20.006

BILLING CODE 3510-22-C
Explosives
Phase III explosive criteria for behavioral Level B harassment
thresholds for marine mammals is the functional hearing groups' TTS
onset threshold (in SEL) minus 5 dB (see Table 18 below and Table 11
for the TTS thresholds for explosives) for events that contain multiple
impulses from explosives underwater. This was the same approach as
taken in Phase II for explosive analysis. See the ``Criteria and
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase
III)'' report (U.S. Department of the Navy, 2017c) for detailed
information on how the criteria and thresholds were derived. NMFS
continues to concur that this approach represents the best available
science for determining impacts to marine mammals from explosives.

Table 18--Behavioral Level B Harassment Thresholds for Explosives for
Marine Mammals
------------------------------------------------------------------------
Functional hearing SEL
Medium group (weighted)
------------------------------------------------------------------------
Underwater..................... Low-frequency cetaceans 163
Underwater..................... Mid-frequency cetaceans 165
Underwater..................... High-frequency 135
cetaceans.
Underwater..................... Phocids................ 165
Underwater..................... Otariids............... 183
------------------------------------------------------------------------
Note: Weighted SEL thresholds in dB re: 1 [mu]Pa\2\s underwater.

Navy's Acoustic Effects Model
The Navy's Acoustic Effects Model calculates sound energy
propagation from sonar and other transducers and explosives during
naval activities and the sound received by animat dosimeters. Animat
dosimeters are virtual representations of marine mammals distributed in
the area around the modeled naval activity and each dosimeter records
its individual sound ``dose.'' The model bases the distribution of
animats over the NWTT Study Area on the density values in the Navy
Marine Species Density Database and distributes animats in the water
column proportional to the known time that species spend at varying
depths.
The model accounts for environmental variability of sound
propagation in both distance and depth when computing the sound level
received by the animats. The model

[[Page 33973]]

conducts a statistical analysis based on multiple model runs to compute
the estimated effects on animals. The number of animats that exceed the
thresholds for effects is tallied to provide an estimate of the number
of marine mammals that could be affected.
Assumptions in the Navy model intentionally err on the side of
overestimation when there are unknowns. Naval activities are modeled as
though they would occur regardless of proximity to marine mammals,
meaning that no mitigation is considered (i.e., no power down or shut
down modeled) and without any avoidance of the activity by the animal.
The final step of the quantitative analysis of acoustic effects is to
consider the implementation of mitigation and the possibility that
marine mammals would avoid continued or repeated sound exposures. For
more information on this process, see the discussion in the Take
Requests subsection below. Many explosions from ordnance such as bombs
and missiles actually occur upon impact with above-water targets.
However, for this analysis, sources such as these were modeled as
exploding underwater. This overestimates the amount of explosive and
acoustic energy entering the water.
The model estimates the impacts caused by individual training and
testing exercises. During any individual modeled event, impacts to
individual animats are considered over 24-hour periods. The animats do
not represent actual animals, but rather they represent a distribution
of animals based on density and abundance data, which allows for a
statistical analysis of the number of instances that marine mammals may
be exposed to sound levels resulting in an effect. Therefore, the model
estimates the number of instances in which an effect threshold was
exceeded over the course of a year, but does not estimate the number of
individual marine mammals that may be impacted over a year (i.e., some
marine mammals could be impacted several times, while others would not
experience any impact). A detailed explanation of the Navy's Acoustic
Effects Model is provided in the technical report ``Quantifying
Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and
Analytical Approach for Phase III Training and Testing'' (U.S.
Department of the Navy, 2018).
Sonar and Other Transducers and Explosives
Range to Effects
The following section provides range to effects for sonar and other
active acoustic sources as well as explosives to specific acoustic
thresholds determined using the Navy Acoustic Effects Model. Marine
mammals exposed within these ranges for the shown duration are
predicted to experience the associated effect. Range to effects is
important information in not only predicting acoustic impacts, but also
in verifying the accuracy of model results against real-world
situations and determining adequate mitigation ranges to avoid higher
level effects, especially physiological effects to marine mammals.
Sonar
The ranges to received sound levels in 6-dB steps from five
representative sonar bins and the percentage of the total number of
animals that may exhibit a significant behavioral response (and
therefore Level B harassment) under each behavioral response function
are shown in Tables 13 through 17 above. See Chapter 6, Section 6.4.2.1
(Methods for Analyzing Impacts from Sonars and Other Transducers) of
the Navy's rulemaking/LOA application for additional details on the
derivation and use of the behavioral response functions, thresholds,
and the cutoff distances that are used to identify Level B behavioral
harassment.
The ranges to PTS for five representative sonar systems for an
exposure of 30 seconds is shown in Table 19 relative to the marine
mammal's functional hearing group. This period (30 seconds) was chosen
based on examining the maximum amount of time a marine mammal would
realistically be exposed to levels that could cause the onset of PTS
based on platform (e.g., ship) speed and a nominal animal swim speed of
approximately 1.5 m per second. The ranges provided in the table
include the average range to PTS, as well as the range from the minimum
to the maximum distance at which PTS is possible for each hearing
group.

Table 19--Range to Permanent Threshold Shift (Meters) for Five Representative Sonar Systems
----------------------------------------------------------------------------------------------------------------
Approximate PTS (30 seconds) ranges (meters) \1\
Hearing group -------------------------------------------------------------------------------
Sonar bin HF4 Sonar bin LF4 Sonar bin MF1 Sonar bin MF4 Sonar bin MF5
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans........ 38 (22-85) 0 (0-0) 195 (80-330) 30 (30-40) 9 (8-11)
Low-frequency cetaceans......... 0 (0-0) 2 (1-3) 67 (60-110) 15 (15-17) 0 (0-0)
Mid-frequency cetaceans......... 1 (0-3) 0 (0-0) 16 (16-19) 3 (3-3) 0 (0-0)
Otariids........................ 0 (0-0) 0 (0-0) 6 (6-6) 0 (0-0) 0 (0-0)
Phocids......................... 0 (0-0) 0 (0-0) 46 (45-75) 11 (11-12) 0 (0-0)
----------------------------------------------------------------------------------------------------------------
\1\ PTS ranges extend from the sonar or other transducer sound source to the indicated distance. The average
range to PTS is provided as well as the range from the estimated minimum to the maximum range to PTS in
parentheses.
Notes: HF = high-frequency, LF = low-frequency, MF = mid-frequency, PTS = permanent threshold shift.

The tables below illustrate the range to TTS for 1, 30, 60, and 120
seconds from five representative sonar systems (see Tables 20 through
24).

Table 20--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin LF4 Over a Representative Range of
Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
---------------------------------------------------------------
Hearing group Sonar bin LF4
---------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans........................ 0 (0-0) 0 (0-0) 0 (0-0) 1 (0-1)

[[Page 33974]]

Low-frequency cetaceans......................... 22 (19-30) 32 (25-230) 41 (30-230) 61 (45-100)
Mid-frequency cetaceans......................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
Otariids........................................ 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
Phocids......................................... 2 (1-3) 4 (3-4) 4 (4-5) 7 (6-9)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone
in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
parentheses.
Notes: HF = high-frequency, TTS = temporary threshold shift.

Table 21--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF1 Over a Representative Range of
Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
---------------------------------------------------------------
Hearing group Sonar bin MF1
---------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans........................ 2,466 (80- 2,466 (80- 3,140 (80- 3,740 (80-
6,275) 6,275) 10,275) 13,525)
Low-frequency cetaceans......................... 1,054 (80- 1,054 (80- 1,480 (80- 1,888 (80-
2,775) 2,775) 4,525) 5,275)
Mid-frequency cetaceans......................... 225 (80-380) 225 (80-380) 331 (80-525) 411 (80-700)
Otariids........................................ 67 (60-110) 67 (60-110) 111 (80-170) 143 (80-250)
Phocids......................................... 768 (80-2,025) 768 (80-2,025) 1,145 (80- 1,388 (80-
3,275) 3,775)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone
in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
parentheses. Ranges for 1 second and 30 second periods are identical for Bin MF1 because this system nominally
pings every 50 seconds; therefore, these periods encompass only a single ping.
Notes: MF = mid-frequency, TTS = temporary threshold shift.

Table 22--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF4 Over a Representative Range of
Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
-------------------------------------------------------------------------
Hearing group Sonar bin MF4
-------------------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans.............. 279 (220-600) 647 (420- 878 (500- 1,205 (525-2,275)
1,275) 1,525)
Low-frequency cetaceans............... 87 (85-110) 176 (130-320) 265 (190-575) 477 (290-975)
Mid-frequency cetaceans............... 22 (22-25) 35 (35-45) 50 (45-55) 71 (70-85)
Otariids.............................. 8 (8-8) 15 (15-17) 19 (19-23) 25 (25-30)
Phocids............................... 66 (65-80) 116 (110-200) 173 (150-300) 303 (240-675)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone
in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
parentheses.
Notes: MF = mid-frequency, TTS = temporary threshold shift.

Table 23--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF5 Over a Representative Range of
Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
---------------------------------------------------------------
Hearing group Sonar bin MF5
---------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans........................ 115 (110-180) 115 (110-180) 174 (150-390) 292 (210-825)
Low-frequency cetaceans......................... 11 (10-13) 11 (10-13) 17 (16-19) 24 (23-25)
Mid-frequency cetaceans......................... 6 (0-9) 6 (0-9) 12 (11-14) 18 (17-22)
Otariids........................................ 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)

[[Page 33975]]

Phocids......................................... 9 (8-11) 9 (8-11) 15 (14-17) 22 (21-25)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone
in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
parentheses.
Notes: MF = mid-frequency, TTS = temporary threshold shift.

Table 24--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin HF4 Over a Representative Range of
Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Approximate TTS Ranges (meters) \1\
---------------------------------------------------------------
Hearing group Sonar bin HF4
---------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans........................ 236 (60-675) 387 (60-875) 503 (60-1,025) 637 (60-1,275)
Low-frequency cetaceans......................... 2 (0-3) 3 (1-6) 5 (3-8) 8 (5-12)
Mid-frequency cetaceans......................... 12 (7-20) 21 (12-40) 29 (17-60) 43 (24-90)
Otariids........................................ 0 (0-0) 0 (0-0) 0 (0-0) 1 (0-1)
Phocids......................................... 3 (0-5) 6 (4-10) 9 (5-15) 14 (8-25)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone
in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
parentheses.
Notes: HF = high-frequency, TTS = temporary threshold shift.

Explosives
The following section provides the range (distance) over which
specific physiological or behavioral effects are expected to occur
based on the explosive criteria (see Chapter 6, Section 6.5.2 (Impacts
from Explosives) of the Navy's rulemaking/LOA application and the
``Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects
Analysis (Phase III)'' report (U.S. Department of the Navy, 2017c)) and
the explosive propagation calculations from the Navy Acoustic Effects
Model (see Chapter 6, Section 6.5.2.2 (Impact Ranges for Explosives) of
the Navy's rulemaking/LOA application). The range to effects are shown
for a range of explosive bins, from E1 (up to 0.25 lb net explosive
weight) to E11 (greater than 500 lb to 650 lb net explosive weight)
(Tables 25 through 31). Ranges are determined by modeling the distance
that noise from an explosion would need to propagate to reach exposure
level thresholds specific to a hearing group that would cause
behavioral response (to the degree of Level B behavioral harassment),
TTS, PTS, and non-auditory injury. NMFS has reviewed the range distance
to effect data provided by the Navy and concurs with the analysis.
Range to effects is important information in not only predicting
impacts from explosives, but also in verifying the accuracy of model
results against real-world situations and determining adequate
mitigation ranges to avoid higher level effects, especially
physiological effects to marine mammals. For additional information on
how ranges to impacts from explosions were estimated, see the technical
report ``Quantifying Acoustic Impacts on Marine Mammals and Sea
Turtles: Methods and Analytical Approach for Phase III Training and
Testing'' (U.S. Navy, 2018).
Tables 25 through 29 show the minimum, average, and maximum ranges
to onset of auditory and likely behavioral effects that rise to the
level of Level B harassment for high-frequency cetaceans based on the
developed thresholds. Ranges are provided for a representative source
depth and cluster size (the number of rounds fired, or buoys dropped,
within a very short duration) for each bin. For events with multiple
explosions, sound from successive explosions can be expected to
accumulate and increase the range to the onset of an impact based on
SEL thresholds. Ranges to non-auditory injury and mortality are shown
in Tables 30 and 31, respectively.
Table 25 shows the minimum, average, and maximum ranges to onset of
auditory and likely behavioral effects that rise to the level of Level
B harassment for high-frequency cetaceans based on the developed
thresholds.

Table 25--SEL-Based Ranges to Onset PTS, Onset TTS, and Behavioral Reaction (in Meters) for High-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: High-frequency cetaceans \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source depth
Bin (m) Cluster size Range to PTS (m) Range to TTS (m) Range to behavioral (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................... 0.1 1 361 (350-370) 1,108 (1,000-1,275) 1,515 (1,025-2,025)
18 1,002 (925-1,025) 2,404 (1,275-4,025) 3,053 (1,275-5,025)
E2........................................... 0.1 1 439 (420-450) 1,280 (1,025-1,775) 1,729 (1,025-2,525)

[[Page 33976]]

5 826 (775-875) 1,953 (1,275-3,025) 2,560 (1,275-4,275)
E3........................................... 10 1 1,647 (160-3,525) 2,942 (160-10,275) 3,232 (160-12,275)
12 3,140 (160-9,525) 3,804 (160-17,525) 3,944 (160-21,775)
18.25 1 684 (550-1,000) 2,583 (1,025-5,025) 4,217 (1,525-7,525)
12 1,774 (1,025-3,775) 5,643 (1,775-10,025) 7,220 (2,025-13,275)
E4........................................... 10 2 1,390 (950-3,025) 5,250 (2,275-8,275) 7,004 (2,775-11,275)
30 2 1,437 (925-2,775) 4,481 (1,525-7,775) 5,872 (2,775-10,525)
70 2 1,304 (925-2,275) 3,845 (2,525-7,775) 5,272 (3,525-9,525)
90 2 1,534 (900-2,525) 5,115 (2,525-7,525) 6,840 (3,275-10,275)
E5........................................... 0.1 1 940 (850-1,025) 2,159 (1,275-3,275) 2,762 (1,275-4,275)
20 1,930 (1,275-2,775) 4,281 (1,775-6,525) 5,176 (2,025-7,775)
E7........................................... 10 1 2,536 (1,275-3,775) 6,817 (2,775-11,025) 8,963 (3,525-14,275)
30 1 1,916 (1,025-4,275) 5,784 (2,775-10,525) 7,346 (2,775-12,025)
E8........................................... 45.75 1 1,938 (1,275-4,025) 4,919 (1,775-11,275) 5,965 (2,025-15,525)
E10.......................................... 0.1 1 1,829 (1,025-2,775) 4,166 (1,775-6,025) 5,023 (2,025-7,525)
E11.......................................... 91.4 1 3,245 (2,025-6,775) 6,459 (2,525-15,275) 7,632 (2,775-19,025)
200 1 3,745 (3,025-5,025) 7,116 (4,275-11,275) 8,727 (5,025-15,025)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (meters) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum distances (due to varying propagation
environments), which are in parentheses.
Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift.

Table 26 shows the minimum, average, and maximum ranges to onset of
auditory and likely behavioral effects that rise to the level of Level
B harassment for low-frequency cetaceans based on the developed
thresholds.

Table 26--SEL-Based Ranges to Onset PTS, Onset TTS, and Behavioral Reaction (in Meters) for Low-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Low-frequency cetaceans \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source depth Range to behavioral
Bin (meters) Cluster size Range to PTS (meters) Range to TTS (meters) (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................... 0.1 1 52 (50-55) 221 (120-250) 354 (160-420)
18 177 (110-200) 656 (230-875) 836 (280-1,025)
E2........................................... 0.1 1 66 (55-70) 276 (140-320) 432 (180-525)
5 128 (90-140) 512 (200-650) 735 (250-975)
E3........................................... 10 1 330 (160-550) 1,583 (160-4,025) 2,085 (160-7,525)
12 1,177 (160-2,775) 2,546 (160-11,775) 2,954 (160-17,025)
18.25 1 198 (180-220) 1,019 (490-2,275) 1,715 (625-4,025)
12 646 (390-1,025) 3,723 (800-9,025) 6,399 (1,025-46,525)
E4........................................... 10 2 462 (400-600) 3,743 (2,025-7,025) 6,292 (2,525-13,275)
30 2 527 (330-950) 3,253 (1,775-4,775) 5,540 (2,275-8,275)
70 2 490 (380-775) 3,026 (1,525-4,775) 5,274 (2,275-7,775)
90 2 401 (360-500) 3,041 (1,275-4,525) 5,399 (1,775-9,275)
E5........................................... 0.1 1 174 (100-260) 633 (220-850) 865 (270-1,275)
20 550 (200-700) 1,352 (420-2,275) 2,036 (700-4,275)
E7........................................... 10 1 1,375 (875-2,525) 7,724 (3,025-15,025) 11,787 (4,525-25,275)
30 1 1,334 (675-2,025) 7,258 (2,775-11,025) 11,644 (4,525-24,275)
E8........................................... 45.75 1 1,227 (575-2,525) 3,921 (1,025-17,275) 7,961 (1,275-48,525)
E10.......................................... 0.1 1 546 (200-700) 1,522 (440-5,275) 3,234 (850-30,525)
E11.......................................... 91.4 1 2,537 (950-5,525) 11,249 (1,775-50,775) 37,926 (6,025-94,775)
200 1 2,541 (1,525-4,775) 7,407 (2,275-43,275) 42,916 (6,275-51,275)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses. Values depict the
range produced by SEL hearing threshold criteria levels.
Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift.

Table 27 shows the minimum, average, and maximum ranges to onset of
auditory and likely behavioral effects that rise to the level of Level
B harassment for mid-frequency cetaceans based on the developed
thresholds.

[[Page 33977]]

Table 27--SEL-Based Ranges to Onset PTS, Onset TTS, and Behavioral Reaction (in Meters) for Mid-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Mid-frequency cetaceans \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
Range to
Bin Source depth Cluster size Range to PTS Range to TTS behavioral
(meters) (meters) (meters) (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1............................................................. 0.1 1 25 (25-25) 118 (110-120) 203 (190-210)
18 96 (90-100) 430 (410-440) 676 (600-700)
E2............................................................. 0.1 1 30 (30-30) 146 (140-150) 246 (230-250)
5 64 (60-65) 298 (290-300) 493 (470-500)
E3............................................................. 10 1 61 (50-100) 512 (160-750) 928 (160-2,025)
12 300 (160-625) 1,604 (160-3,525) 2,085 (160-5,525)
18.25 1 40 (35-40) 199 (180-280) 368 (310-800)
12 127 (120-130) 709 (575-1,000) 1,122 (875-2,525)
E4............................................................. 10 2 73 (70-75) 445 (400-575) 765 (600-1,275)
30 2 71 (65-90) 554 (320-1,025) 850 (525-1,775)
70 2 63 (60-85) 382 (320-675) 815 (525-1,275)
90 2 59 (55-85) 411 (310-900) 870 (525-1,275)
E5............................................................. 0.1 1 79 (75-80) 360 (350-370) 575 (525-600)
20 295 (280-300) 979 (800-1,275) 1,442 (925-1,775)
E7............................................................. 10 1 121 (110-130) 742 (575-1,275) 1,272 (875-2,275)
30 1 111 (100-130) 826 (500-1,775) 1,327 (925-2,275)
E8............................................................. 45.75 1 133 (120-170) 817 (575-1,525) 1,298 (925-2,525)
E10............................................................ 0.1 1 273 (260-280) 956 (775-1,025) 1,370 (900-1,775)
E11............................................................ 91.4 1 242 (220-310) 1,547 (1,025- 2,387 (1,275-
3,025) 4,025)
200 1 209 (200-300) 1,424 (1,025- 2,354 (1,525-
2,025) 3,775)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses.
Note: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift.

Table 28 shows the minimum, average, and maximum ranges to onset of
auditory and likely behavioral effects that rise to the level of Level
B harassment for otariid pinnipeds based on the developed thresholds.

Table 28--SEL-Based Ranges to Onset PTS, Onset TTS, and Behavioral Reaction (in Meters) for Otariids
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Otariids \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
Range to
Bin Source depth Cluster size Range to PTS Range to TTS behavioral
(meters) (meters) (meters) (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1............................................................. 0.1 1 7 (7-8) 34 (30-35) 58 (55-60)
18 25 (25-25) 124 (120-130) 208 (200-210)
E2............................................................. 0.1 1 9 (9-10) 43 (40-45) 72 (70-75)
5 19 (19-20) 88 (85-90) 145 (140-150)
E3............................................................. 10 1 21 (18-25) 135 (120-210) 250 (160-370)
12 82 (75-100) 551 (160-875) 954 (160-2,025)
18.25 1 15 (15-15) 91 (85-95) 155 (150-160)
12 53 (50-55) 293 (260-430) 528 (420-825)
E4............................................................. 10 2 30 (30-30) 175 (170-180) 312 (300-350)
30 2 25 (25-25) 176 (160-250) 400 (290-750)
70 2 26 (25-35) 148 (140-200) 291 (250-400)
90 2 26 (25-35) 139 (130-190) 271 (250-360)
E5............................................................. 0.1 1 25 (24-25) 111 (110-120) 188 (180-190)
20 93 (90-95) 421 (390-440) 629 (550-725)
E7............................................................. 10 1 60 (60-60) 318 (300-360) 575 (500-775)
30 1 53 (50-65) 376 (290-700) 742 (500-1,025)
E8............................................................. 45.75 1 55 (55-55) 387 (310-750) 763 (525-1,275)
E10............................................................ 0.1 1 87 (85-90) 397 (370-410) 599 (525-675)
E11............................................................ 91.4 1 100 (100-100) 775 (550-1,275) 1,531 (900-3,025)
200 1 94 (90-100) 554 (525-700) 1,146 (900-1,525)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses.
Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift.

Table 29 shows the minimum, average, and maximum ranges to onset of
auditory and likely behavioral effects that rise to the level of Level
B harassment for phocid pinnipeds based on the developed thresholds.

[[Page 33978]]

Table 29--SEL-Based Ranges to Onset PTS, Onset TTS, and Behavioral Reaction (in Meters) for Phocids
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Phocids \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source depth Range to behavioral
Bin (meters) Cluster size Range to PTS (meters) Range to TTS (meters) (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................... 0.1 1 47 (45-50) 219 (210-230) 366 (350-370)
18 171 (160-180) 764 (725-800) 1,088 (1,025-1,275)
E2........................................... 0.1 1 59 (55-60) 273 (260-280) 454 (440-460)
5 118 (110-120) 547 (525-550) 881 (825-925)
E3........................................... 10 1 185 (160-260) 1,144 (160-2,775) 1,655 (160-4,525)
12 760 (160-1,525) 2,262 (160-8,025) 2,708 (160-12,025)
18.25 1 112 (110-120) 628 (500-950) 1,138 (875-2,525)
12 389 (330-625) 2,248 (1,275-4,275) 4,630 (1,275-8,525)
E4........................................... 10 2 226 (220-240) 1,622 (950-3,275) 3,087 (1,775-5,775)
30 2 276 (200-600) 1,451 (1,025-2,275) 2,611 (1,775-4,275)
70 2 201 (180-280) 1,331 (1,025-1,775) 2,403 (1,525-3,525)
90 2 188 (170-270) 1,389 (975-2,025) 2,617 (1,775-3,775)
E5........................................... 0.1 1 151 (140-160) 685 (650-700) 1,002 (950-1,025)
20 563 (550-575) 1,838 (1,275-2,275) 2,588 (1,525-3,525)
E7........................................... 10 1 405 (370-490) 3,185 (1,775-6,025) 5,314 (2,275-11,025)
30 1 517 (370-875) 2,740 (1,775-4,275) 4,685 (3,025-7,275)
E8........................................... 45.75 1 523 (390-1,025) 2,502 (1,525-6,025) 3,879 (2,025-10,275)
E10.......................................... 0.1 1 522 (500-525) 1,800 (1,275-2,275) 2,470 (1,525-3,275)
E11.......................................... 91.4 1 1,063 (675-2,275) 5,043 (2,775-10,525) 7,371 (3,275-18,025)
200 1 734 (675-850) 5,266 (3,525-9,025) 7,344 (5,025-12,775)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (meters) is shown with the minimum and maximum distances due to varying propagation environments in parentheses.
Notes: PTS = permanent threshold shift, SEL = sound exposure level, TTS = temporary threshold shift.

Table 30 shows the minimum, average, and maximum ranges due to
varying propagation conditions to non-auditory injury as a function of
animal mass and explosive bin (i.e., net explosive weight). Ranges to
gastrointestinal tract injury typically exceed ranges to slight lung
injury; therefore, the maximum range to effect is not mass-dependent.
Animals within these water volumes would be expected to receive minor
injuries at the outer ranges, increasing to more substantial injuries,
and finally mortality as an animal approaches the detonation point.

Table 30--Ranges \1\ to Non-Auditory Injury (in Meters) for All Marine
Mammal Hearing Groups
------------------------------------------------------------------------
Range to non-
auditory
Bin injury
(meters) \1\
------------------------------------------------------------------------
E1...................................................... 12 (11-13)
E2...................................................... 16 (15-16)
E3...................................................... 25 (25-45)
E4...................................................... 31 (23-50)
E5...................................................... 40 (40-40)
E7...................................................... 104 (80-190)
E8...................................................... 149 (130-210)
E10..................................................... 153 (100-400)
E11..................................................... 419 (350-725)
------------------------------------------------------------------------
\1\ Distances in meters (m). Average distance is shown with the minimum
and maximum distances due to varying propagation environments in
parentheses. Modeled ranges based on peak pressure for a single
explosion generally exceed the modeled ranges based on impulse
(related to animal mass and depth).

Ranges to mortality, based on animal mass, are shown in Table 31
below.

Table 31--Ranges \1\ to Mortality (in Meters) for All Marine Mammal Hearing Groups as a Function of Animal Mass
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to mortality (meters) for various animal mass intervals (kg) \1\
Bin -----------------------------------------------------------------------------------------------
10 kg 250 kg 1,000 kg 5,000 kg 25,000 kg 72,000 kg
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1...................................................... 3 (2-3) 1 (0-3) 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
E2...................................................... 4 (3-5) 2 (1-3) 1 (0-1) 0 (0-0) 0 (0-0) 0 (0-0)
E3...................................................... 10 (9-20) 5 (3-20) 2 (1-5) 0 (0-3) 0 (0-1) 0 (0-1)
E4...................................................... 13 (11-19) 7 (4-13) 3 (2-4) 2 (1-3) 1 (1-1) 1 (0-1)
E5...................................................... 13 (11-15) 7 (4-11) 3 (3-4) 2 (1-3) 1 (1-1) 1 (0-1)
E7...................................................... 49 (40-80) 27 (15-60) 13 (10-20) 9 (5-12) 4 (4-6) 3 (2-4)
E8...................................................... 65 (60-75) 34 (22-55) 17 (14-20) 11 (9-13) 6 (5-6) 5 (4-5)
E10..................................................... 43 (40-50) 25 (16-40) 13 (11-16) 9 (7-11) 5 (4-6) 4 (3-4)
E11..................................................... 185 (90-230) 90 (30-170) 40 (30-50) 28 (23-30) 15 (13-16) 11 (9-13)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance to mortality (meters) is depicted above the minimum and maximum distances, which are in parentheses for each animal mass interval.
Notes: kg = kilogram.

[[Page 33979]]

Marine Mammal Density

A quantitative analysis of impacts on a species or stock requires
data on their abundance and distribution that may be affected by
anthropogenic activities in the potentially impacted area. The most
appropriate metric for this type of analysis is density, which is the
number of animals present per unit area. Marine species density
estimation requires a significant amount of effort to both collect and
analyze data to produce a reasonable estimate. Unlike surveys for
terrestrial wildlife, many marine species spend much of their time
submerged, and are not easily observed. In order to collect enough
sighting data to make reasonable density estimates, multiple
observations are required, often in areas that are not easily
accessible (e.g., far offshore). Ideally, marine mammal species
sighting data would be collected for the specific area and time period
(e.g., season) of interest and density estimates derived accordingly.
However, in many places, poor weather conditions and high sea states
prohibit the completion of comprehensive visual surveys.
For most cetacean species, abundance is estimated using line-
transect surveys or mark-recapture studies (e.g., Barlow, 2010; Barlow
and Forney, 2007; Calambokidis et al., 2008). The result provides one
single density estimate value for each species across broad geographic
areas. This is the general approach applied in estimating cetacean
abundance in NMFS' Stock Assessment Reports (SARs). Although the single
value provides a good average estimate of abundance (total number of
individuals) for a specified area, it does not provide information on
the species distribution or concentrations within that area, and it
does not estimate density for other timeframes or seasons that were not
surveyed. More recently, spatial habitat modeling developed by NMFS'
Southwest Fisheries Science Center has been used to estimate cetacean
densities (Barlow et al., 2009; Becker et al., 2010, 2012a, b, c, 2014,
2016; Ferguson et al., 2006a; Forney et al., 2012, 2015; Redfern et
al., 2006). These models estimate cetacean density as a continuous
function of habitat variables (e.g., sea surface temperature, seafloor
depth, etc.) and thus allow predictions of cetacean densities on finer
spatial scales than traditional line-transect or mark recapture
analyses and for areas that have not been surveyed. Within the
geographic area that was modeled, densities can be predicted wherever
these habitat variables can be measured or estimated.
Ideally, density data would be available for all species throughout
the study area year-round, in order to best estimate the impacts of
Navy activities on marine species. However, in many places, ship
availability, lack of funding, inclement weather conditions, and high
sea states prevent the completion of comprehensive year-round surveys.
Even with surveys that are completed, poor conditions may result in
lower sighting rates for species that would typically be sighted with
greater frequency under favorable conditions. Lower sighting rates
preclude having an acceptably low uncertainty in the density estimates.
A high level of uncertainty, indicating a low level of confidence in
the density estimate, is typical for species that are rare or difficult
to sight. In areas where survey data are limited or non-existent, known
or inferred associations between marine habitat features and the likely
presence of specific species are sometimes used to predict densities in
the absence of actual animal sightings. Consequently, there is no
single source of density data for every area, species, and season
because of the fiscal costs, resources, and effort involved in
providing enough survey coverage to sufficiently estimate density.
To characterize marine species density for large oceanic regions,
the Navy reviews, critically assesses, and prioritizes existing density
estimates from multiple sources, requiring the development of a
systematic method for selecting the most appropriate density estimate
for each combination of species/stock, area, and season. The selection
and compilation of the best available marine species density data
resulted in the Navy Marine Species Density Database (NMSDD), which
includes seasonal density values for every marine mammal species and
stock present within the NWTT Study Area. This database is described in
the technical report titled ``U.S. Navy Marine Species Density Database
Phase III for the Northwest Training and Testing Study Area'' (U.S.
Department of the Navy, 2019), hereafter referred to as the Density
Technical Report. NMFS vetted all cetacean densities by the Navy prior
to use in the Navy's acoustic analysis for the current NWTT rulemaking
process.
A variety of density data and density models are needed in order to
develop a density database that encompasses the entirety of the NWTT
Study Area. Because this data is collected using different methods with
varying amounts of accuracy and uncertainty, the Navy has developed a
hierarchy to ensure the most accurate data is used when available. The
Density Technical Report describes these models in detail and provides
detailed explanations of the models applied to each species density
estimate. The below list describes models in order of preference.
1. Spatial density models are preferred and used when available
because they provide an estimate with the least amount of uncertainty
by deriving estimates for divided segments of the sampling area. These
models (see Becker et al., 2016; Forney et al., 2015) predict spatial
variability of animal presence as a function of habitat variables
(e.g., sea surface temperature, seafloor depth, etc.). This model is
developed for areas, species, and, when available, specific timeframes
(months or seasons) with sufficient survey data; therefore, this model
cannot be used for species with low numbers of sightings.
2. Stratified design-based density estimates use line-transect
survey data with the sampling area divided (stratified) into sub-
regions, and a density is predicted for each sub-region (see Barlow,
2016; Becker et al., 2016; Bradford et al., 2017; Campbell et al.,
2014; Jefferson et al., 2014). While geographically stratified density
estimates provide a better indication of a species' distribution within
the study area, the uncertainty is typically high because each sub-
region estimate is based on a smaller stratified segment of the overall
survey effort.
3. Design-based density estimations use line-transect survey data
from land and aerial surveys designed to cover a specific geographic
area (see Carretta et al., 2015). These estimates use the same survey
data as stratified design-based estimates, but are not segmented into
sub-regions and instead provide one estimate for a large surveyed area.
Although relative environmental suitability (RES) models provide
estimates for areas of the oceans that have not been surveyed using
information on species occurrence and inferred habitat associations and
have been used in past density databases, these models were not used in
the current quantitative analysis.
The Navy describes some of the challenges of interpreting the
results of the quantitative analysis summarized above and described in
the Density Technical Report: ``It is important to consider that even
the best estimate of marine species density is really a model
representation of the values of concentration where these animals might
occur. Each model is limited to the variables and assumptions
considered by the original data source provider. No mathematical model
representation of any biological

[[Page 33980]]

population is perfect, and with regards to marine mammal biodiversity,
any single model method will not completely explain the actual
distribution and abundance of marine mammal species. It is expected
that there would be anomalies in the results that need to be evaluated,
with independent information for each case, to support if we might
accept or reject a model or portions of the model (U.S. Department of
the Navy, 2017a).''
The Navy's estimate of abundance (based on density estimates used
in the NWTT Study Area) utilizes NMFS' SARs, except for species with
high site fidelity/smaller home ranges within the NWTT Study Area,
relative to their geographic distribution (e.g., harbor seals). For
harbor seals in the inland waters, more up-to-date, site specific
population estimates were available. For some species, the stock
assessment for a given species may exceed the Navy's density prediction
because those species' home range extends beyond the Study Area
boundaries. For other species, the stock assessment abundance may be
much less than the number of animals in the Navy's modeling given that
the NWTT Study Area extends beyond the U.S waters covered by the SAR
abundance estimate. The primary source of density estimates are
geographically specific survey data and either peer-reviewed line-
transect estimates or habitat-based density models that have been
extensively validated to provide the most accurate estimates possible.
NMFS coordinated with the Navy in the development of its take
estimates and concurs that the Navy's approach for density
appropriately utilizes the best available science. Later, in the
Preliminary Analysis and Negligible Impact Determination section, we
assess how the estimated take numbers compare to stock abundance in
order to better understand the potential number of individuals
impacted, and the rationale for which abundance estimate is used is
included there.

Take Request

The 2019 NWTT DSEIS/OEIS considered all training and testing
activities proposed to occur in the NWTT Study Area that have the
potential to result in the MMPA defined take of marine mammals. The
Navy determined that the three stressors below could result in the
incidental taking of marine mammals. NMFS has reviewed the Navy's data
and analysis and determined that it is complete and accurate and agrees
that the following stressors have the potential to result in takes by
harassment of marine mammals from the Navy's planned activities.
Acoustics (sonar and other transducers);
Explosives (explosive shock wave and sound, assumed to
encompass the risk due to fragmentation); and
Vessel strike
Acoustic and explosive sources have the potential to result in
incidental takes of marine mammals by harassment and injury. Vessel
strikes have the potential to result in incidental take from injury,
serious injury, and/or mortality.
The quantitative analysis process used for the 2019 NWTT DSEIS/OEIS
and the Navy's take request in the rulemaking/LOA application to
estimate potential exposures to marine mammals resulting from acoustic
and explosive stressors is detailed in the technical report titled
Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods
and Analytical Approach for Phase III Training and Testing (U.S.
Department of the Navy, 2018). The Navy Acoustic Effects Model
estimates acoustic and explosive effects without taking mitigation into
account; therefore, the model overestimates predicted impacts on marine
mammals within mitigation zones. To account for mitigation for marine
species in the take estimates, the Navy conducts a quantitative
assessment of mitigation. The Navy conservatively quantifies the manner
in which procedural mitigation is expected to reduce the risk for
model-estimated PTS for exposures to sonars and for model-estimated
mortality for exposures to explosives, based on species sightability,
observation area, visibility, and the ability to exercise positive
control over the sound source. Where the analysis indicates mitigation
would effectively reduce risk, the model-estimated PTS are considered
reduced to TTS and the model-estimated mortalities are considered
reduced to injury. For a complete explanation of the process for
assessing the effects of mitigation, see the Navy's rulemaking/LOA
application and the technical report titled Quantifying Acoustic
Impacts on Marine Mammals and Sea Turtles: Methods and Analytical
Approach for Phase III Training and Testing (U.S. Department of the
Navy, 2018). The extent to which the mitigation areas reduce impacts on
the affected species is addressed separately in the Preliminary
Analysis and Negligible Impact Determination section.
The Navy assessed the effectiveness of its procedural mitigation
measures on a per-scenario basis for four factors: (1) Species
sightability, (2) a Lookout's ability to observe the range to PTS (for
sonar and other transducers) and range to mortality (for explosives),
(3) the portion of time when mitigation could potentially be conducted
during periods of reduced daytime visibility (to include inclement
weather and high sea-state) and the portion of time when mitigation
could potentially be conducted at night, and (4) the ability for sound
sources to be positively controlled (e.g., powered down).
During training and testing activities, there is typically at least
one, if not numerous, support personnel involved in the activity (e.g.,
range support personnel aboard a torpedo retrieval boat or support
aircraft). In addition to the Lookout posted for the purpose of
mitigation, these additional personnel observe and disseminate marine
species sighting information amongst the units participating in the
activity whenever possible as they conduct their primary mission
responsibilities. However, as a conservative approach to assigning
mitigation effectiveness factors, the Navy elected to only account for
the minimum number of required Lookouts used for each activity;
therefore, the mitigation effectiveness factors may underestimate the
likelihood that some marine mammals may be detected during activities
that are supported by additional personnel who may also be observing
the mitigation zone.
The Navy used the equations in the below sections to calculate the
reduction in model-estimated mortality impacts due to implementing
procedural mitigation.
Equation 1:

Mitigation Effectiveness = Species Sightability x Visibility x
Observation Area x Positive Control

Species Sightability is the ability to detect marine mammals and is
dependent on the animal's presence at the surface and the
characteristics of the animal that influence its sightability. The Navy
considered applicable data from the best available science to
numerically approximate the sightability of marine mammals and
determined the standard ``detection probability'' referred to as g(0)
is most appropriate. Also, Visibility = 1-sum of individual visibility
reduction factors; Observation Area = portion of impact range that can
be continuously observed during an event; and Positive Control =
positive control factor of all sound sources involving mitigation. For
further details on these mitigation effectiveness factors please refer
to the technical report titled Quantifying Acoustic Impacts on Marine
Mammals and Sea Turtles: Methods and Analytical Approach for Phase III
Training and

[[Page 33981]]

Testing (U.S. Department of the Navy, 2018).
To quantify the number of marine mammals predicted to be sighted by
Lookouts in the injury zone during implementation of procedural
mitigation for sonar and other transducers, the species sightability is
multiplied by the mitigation effectiveness scores and number of model-
estimated PTS impacts, as shown in the equation below:
Equation 2:

Number of Animals Sighted by Lookouts = Mitigation Effectiveness x
Model-Estimated Impacts

The marine mammals sighted by Lookouts in the injury zone during
implementation of mitigation, as calculated by the equation above,
would avoid being exposed to these higher level impacts. To quantify
the number of marine mammals predicted to be sighted by Lookouts in the
mortality zone during implementation of procedural mitigation during
events using explosives, the species sightability is multiplied by the
mitigation effectiveness scores and number of model-estimated mortality
impacts, as shown in equation 1 above. The marine mammals predicted to
be sighted in the mortality zone by Lookouts during implementation of
procedural mitigation, as calculated by the above equation 2, are
predicted to avoid exposure in these ranges. The Navy corrects the
category of predicted impact for the number of animals sighted within
the mitigation zone, but does not modify the total number of animals
predicted to experience impacts from the scenario. For example, the
number of animals sighted (i.e., number of animals that will avoid
mortality) is first subtracted from the model-predicted mortality
impacts, and then added to the model-predicted injurious impacts.
The NAEMO (animal movement) model overestimates the number of
marine mammals that would be exposed to sound sources that could cause
PTS because the model does not consider horizontal movement of animats,
including avoidance of high intensity sound exposures. Therefore, the
potential for animal avoidance is considered separately. At close
ranges and high sound levels, avoidance of the area immediately around
the sound source is one of the assumed behavioral responses for marine
mammals. Animal avoidance refers to the movement out of the immediate
injury zone for subsequent exposures, not wide-scale area avoidance.
Various researchers have demonstrated that cetaceans can perceive the
location and movement of a sound source (e.g., vessel, seismic source,
etc.) relative to their own location and react with responsive movement
away from the source, often at distances of 1 km or more (Au &
Perryman,1982; Jansen et al., 2010; Richardson et al., 1995; Tyack et
al., 2011; Watkins, 1986; W[uuml]rsig et al., 1998) A marine mammal's
ability to avoid a sound source and reduce its cumulative sound energy
exposure would reduce risk of both PTS and TTS. However, the
quantitative analysis conservatively only considers the potential to
reduce some instances of PTS by accounting for marine mammals swimming
away to avoid repeated high-level sound exposures. All reductions in
PTS impacts from likely avoidance behaviors are instead considered TTS
impacts.
NMFS coordinated with the Navy in the development of this
quantitative method to address the effects of procedural mitigation on
acoustic and explosive exposures and takes, and NMFS independently
reviewed and concurs with the Navy that it is appropriate to
incorporate the quantitative assessment of mitigation into the take
estimates based on the best available science. For additional
information on the quantitative analysis process and mitigation
measures, refer to the technical report titled Quantifying Acoustic
Impacts on Marine Mammals and Sea Turtles: Methods and Analytical
Approach for Phase III Training and Testing (U.S. Department of the
Navy, 2018) and Chapter 6 (Take Estimates for Marine Mammals) and
Chapter 11 (Mitigation Measures) of the Navy's rulemaking/LOA
application.
As a general matter, NMFS does not prescribe the methods for
estimating take for any applicant, but we review and ensure that
applicants use the best available science, and methodologies that are
logical and technically sound. Applicants may use different methods of
calculating take (especially when using models) and still get to a
result that is representative of the best available science and that
allows for a rigorous and accurate evaluation of the effects on the
affected populations. There are multiple pieces of the Navy take
estimation methods--propagation models, animat movement models, and
behavioral thresholds, for example. NMFS evaluates the acceptability of
these pieces as they evolve and are used in different rules and impact
analyses. Some of the pieces of the Navy's take estimation process have
been used in Navy incidental take rules since 2009 and undergone
multiple public comment processes; all of them have undergone extensive
internal Navy review, and all of them have undergone comprehensive
review by NMFS, which has sometimes resulted in modifications to
methods or models.
The Navy uses rigorous review processes (verification, validation,
and accreditation processes; peer and public review) to ensure the data
and methodology it uses represent the best available science. For
instance, the NAEMO model is the result of a NMFS-led Center for
Independent Experts (CIE) review of the components used in earlier
models. The acoustic propagation component of the NAEMO model (CASS/
GRAB) is accredited by the Oceanographic and Atmospheric Master Library
(OAML), and many of the environmental variables used in the NAEMO model
come from approved OAML databases and are based on in-situ data
collection. The animal density components of the NAEMO model are base
products of the NMSDD, which includes animal density components that
have been validated and reviewed by a variety of scientists from NMFS
Science Centers and academic institutions. Several components of the
model, for example the Duke University habitat-based density models,
have been published in peer reviewed literature. Others like the
Atlantic Marine Assessment Program for Protected Species, which was
conducted by NMFS Science Centers, have undergone quality assurance and
quality control (QA/QC) processes. Finally, the NAEMO model simulation
components underwent QA/QC review and validation for model parts such
as the scenario builder, acoustic builder, scenario simulator, etc.,
conducted by qualified statisticians and modelers to ensure accuracy.
Other models and methodologies have gone through similar review
processes.
In summary, we believe the Navy's methods, including the method for
incorporating mitigation and avoidance, are the most appropriate
methods for predicting PTS, tissue damage, TTS, and behavioral
disruption. But even with the consideration of mitigation and
avoidance, given some of the more conservative components of the
methodology (e.g., the thresholds do not consider ear recovery between
pulses), we would describe the application of these methods as
identifying the maximum number of instances in which marine mammals
would be reasonably expected to be taken through PTS, tissue damage,
TTS, or behavioral disruption.

[[Page 33982]]

Summary of Requested Take From Training and Testing Activities
Based on the methods discussed in the previous sections and the
Navy's model and quantitative assessment of mitigation, the Navy
provided its take estimate and request for authorization of takes
incidental to the use of acoustic and explosive sources for training
and testing activities both annually (based on the maximum number of
activities that could occur per 12-month period) and over the seven-
year period covered by the Navy's rulemaking/LOA application. The
following species/stocks present in the NWTT Study Area were modeled by
the Navy and estimated to have 0 takes of any type from any activity
source: Eastern North Pacific Northern Resident stock of killer whales,
Western North Pacific stock of gray whales, and California stock of
harbor seals. NMFS has reviewed the Navy's data, methodology, and
analysis and determined that it is complete and accurate. NMFS agrees
that the estimates for incidental takes by harassment from all sources
requested for authorization are the maximum number of instances in
which marine mammals are reasonably expected to be taken.
Estimated Harassment Take From Training and Testing Activities
For training and testing activities, Tables 32 and 33 summarize the
Navy's take estimate and request and the annual and maximum amount and
type of Level A harassment and Level B harassment for the seven-year
period that NMFS concurs is reasonably expected to occur by species and
stock. Note that take by Level B harassment includes both behavioral
disruption and TTS. Tables 6-14-41 (sonar and other transducers) and 6-
56-71 (explosives) in Section 6 of the Navy's rulemaking/LOA
application provide the comparative amounts of TTS and behavioral
disruption for each species and stock annually, noting that if a
modeled marine mammal was ``taken'' through exposure to both TTS and
behavioral disruption in the model, it was recorded as a TTS.

Table 32--Annual and Seven-Year Total Species-Specific Take Estimates Proposed for Authorization From Acoustic
and Explosive Sound Source Effects for all Training Activities in the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Annual 7-Year total
Species Stock ---------------------------------------------------------------
Level B Level A Level B Level A
----------------------------------------------------------------------------------------------------------------
Order Cetacea
----------------------------------------------------------------------------------------------------------------
Suborder Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
Family Balaenopteridae
(rorquals):
Blue whale *.............. Eastern North 2 0 11 0
Pacific.
Fin whale *............... Northeast 0 0 0 0
Pacific.
California/ 54 0 377 0
Oregon/
Washington.
Sei whale *............... Eastern North 30 0 206 0
Pacific.
Minke whale............... Alaska.......... 0 0 0 0
California/ 110 0 767 0
Oregon/
Washington.
Humpback whale *.......... Central North 5 0 31 0
Pacific.
California/ 4 0 32 0
Oregon/
Washington.
Family Eschrichtiidae (gray
whale):
Gray whale................ Eastern North 2 0 10 0
Pacific.
----------------------------------------------------------------------------------------------------------------
Suborder Odontoceti (toothed whales)
----------------------------------------------------------------------------------------------------------------
Family Delphinidae (dolphins):
Bottlenose dolphin........ California/ 5 0 33 0
Oregon/
Washington
Offshore.
Killer whale.............. Alaska Resident. 0 0 0 0
Eastern North 68 0 478 0
Pacific
Offshore.
West Coast 78 0 538 0
Transient.
Southern 3 0 15 0
Resident
[cross5].
Northern right whale California/ 7,941 0 55,493 0
dolphin. Oregon/
Washington.
Pacific white-sided North Pacific... 0 0 0 0
dolphin.
California/ 5,284 0 36,788 0
Oregon/
Washington.
Risso's dolphin........... California/ 2,286 0 15,972 0
Oregon/
Washington.
Short-beaked common California/ 1,165 0 8,124 0
dolphin. Oregon/
Washington.
Short-finned pilot whale.. California/ 57 0 398 0
Oregon/
Washington.
Striped dolphin........... California/ 439 0 3,059 0
Oregon/
Washington.
Family Kogiidae (Kogia
species):
Kogia species Pygmy....... California/ 381 0 2,664 0
Oregon/
Washington.
Family Phocoenidae
(porpoises):
Dall's porpoise........... Alaska.......... 0 0 0 0
California/ 13,299 8 92,793 48
Oregon/
Washington.
Harbor porpoise........... Southeast Alaska 0 0 0 0
Northern Oregon/ 299 0 2,092 0
Washington
Coast.
Northern 21 0 145 0
California/
Southern Oregon.
Washington 12,315 43 79,934 291
Inland Waters.
Family Physeteridae (sperm
whale):
Sperm whale *............. California/ 512 0 3,574 0
Oregon/
Washington.
Family Ziphiidae (beaked
whales):
Baird's beaked whale...... California/ 556 0 3,875 0
Oregon/
Washington.
Cuvier's beaked whale..... California/ 1,462 0 10,209 0
Oregon/
Washington.

[[Page 33983]]

Mesoplodon species........ California/ 652 0 4,549 0
Oregon/
Washington.
----------------------------------------------------------------------------------------------------------------
Suborder Pinnipedia
----------------------------------------------------------------------------------------------------------------
Family Otariidae (sea lions
and fur seals):
California sea lion....... U.S. Stock...... 3,624 0 25,243 0
Steller sea lion.......... Eastern U.S..... 108 0 743 0
Guadalupe fur seal *...... Mexico.......... 608 0 4,247 0
Northern fur seal......... Eastern Pacific. 2,134 0 14,911 0
California...... 43 0 300 0
Family Phocidae (true seals):
Harbor seal............... Southeast 0 0 0 0
Alaska--Clarenc
e Strait.
Oregon/ 0 0 0 0
Washington
Coastal.
Washington 669 5 3,938 35
Northern Inland
Waters.
Hood Canal...... 2,686 1 18,662 5
Southern Puget 1,090 1 6,657 6
Sound.
Northern elephant seal.... California...... 1,909 1 13,324 1
----------------------------------------------------------------------------------------------------------------
* ESA-listed species (all stocks) within the NWTT Study Area.
[cross5] Only designated stocks are ESA-listed.

Table 33--Annual and Seven-Year Total Species-Specific Take Estimates Proposed for Authorization From Acoustic
and Explosive Sound Source Effects for all Training Activities in the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
Annual 7-Year total
Species Stock ---------------------------------------------------------------
Level B Level A Level B Level A
----------------------------------------------------------------------------------------------------------------
Order Cetacea
----------------------------------------------------------------------------------------------------------------
Suborder Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
Family Balaenopteridae
(rorquals):
Blue whale *.............. Eastern North 8 0 38 0
Pacific.
Fin whale *............... Northeast 2 0 10 0
Pacific.
California/ 81 0 392 0
Oregon/
Washington.
Sei whale *............... Eastern North 53 0 258 0
Pacific.
Minke whale............... Alaska.......... 2 0 9 0
California/ 192 0 916 0
Oregon/
Washington.
Humpback whale *.......... Central North 110 0 578 0
Pacific.
California/ 89 0 460 0
Oregon/
Washington.
Family Eschrichtiidae (gray
whale):
Gray whale................ Eastern North 41 0 189 0
Pacific.
----------------------------------------------------------------------------------------------------------------
Suborder Odontoceti (toothed whales)
----------------------------------------------------------------------------------------------------------------
Family Delphinidae (dolphins):
Bottlenose dolphin........ California/ 3 0 14 0
Oregon/
Washington
Offshore.
Killer whale.............. Alaska Resident. 34 0 202 0
Eastern North 89 0 412 0
Pacific
Offshore.
West Coast 154 0 831 0
Transient.
Southern 48 0 228 0
Resident
[cross5].
Northern right whale California/ 13,759 1 66,457 7
dolphin. Oregon/
Washington.
Pacific white-sided North Pacific... 101 0 603 0
dolphin.
California/ 15,681 1 76,980 8
Oregon/
Washington.
Risso's dolphin........... California/ 4,069 0 19,637 0
Oregon/
Washington.
Short-beaked common California/ 984 0 3,442 0
dolphin. Oregon/
Washington.
Short-finned pilot whale.. California/ 31 0 126 0
Oregon/
Washington.
Striped dolphin........... California/ 344 0 1,294 0
Oregon/
Washington.
Family Kogiidae (Kogia
species):
Kogia species............. California/ 501 1 2,376 9
Oregon/
Washington.
Family Phocoenidae
(porpoises):
Dall's porpoise........... Alaska.......... 638 0 3,711 0
California/ 20,398 90 98,470 523
Oregon/
Washington.
Harbor porpoise........... Southeast Alaska 130 0 794 0
Northern Oregon/ 52,113 103 265,493 525
Washington
Coast.

[[Page 33984]]

Northern 2,018 86 12,131 432
California/
Southern Oregon.
Washington 17,228 137 115,770 930
Inland Waters.
Family Physeteridae (sperm
whale):
Sperm whale *............. California/ 327 0 1,443 0
Oregon/
Washington.
Family Ziphiidae (beaked
whales):
Baird's beaked whale...... California/ 420 0 1,738 0
Oregon/
Washington.
Cuvier's beaked whale..... California/ 1,077 0 4,979 0
Oregon/
Washington.
Mesoplodon species........ California/ 470 0 2,172 0
Oregon/
Washington.
----------------------------------------------------------------------------------------------------------------
Suborder Pinnipedia
----------------------------------------------------------------------------------------------------------------
Family Otariidae (sea lions
and fur seals):
California sea lion....... U.S. Stock...... 20,474 1 93,906 5
Steller sea lion.......... Eastern U.S..... 2,130 0 10,745 0
Guadalupe fur seal *...... Mexico.......... 887 0 4,022 0
Northern fur seal......... Eastern Pacific. 9,458 0 45,813 0
California...... 189 0 920 0
Family Phocidae (true seals):
Harbor seal............... Southeast 2,352 0 13,384 0
Alaska--Clarenc
e Strait.
Oregon/ 1,180 2 6,222 11
Washington
Coastal.
Washington 578 0 3,227 0
Northern Inland
Waters.
Hood Canal...... 58,784 0 396,883 0
Southern Puget 5,748 3 39,511 24
Sound.
Northern elephant seal.... California...... 2,935 3 14,120 18
----------------------------------------------------------------------------------------------------------------
* ESA-listed species (all stocks) within the NWTT Study Area.
[cross5] Only designated stocks are ESA-listed.

Estimated Take From Vessel Strikes by Serious Injury or Mortality
Vessel strikes from commercial, recreational, and military vessels
are known to affect large whales and have resulted in serious injury
and occasional fatalities to cetaceans (Berman-Kowalewski et al., 2010;
Calambokidis, 2012; Douglas et al., 2008; Laggner 2009; Lammers et al.,
2003). Records of collisions date back to the early 17th century, and
the worldwide number of collisions appears to have increased steadily
during recent decades (Laist et al., 2001; Ritter 2012).
Numerous studies of interactions between surface vessels and marine
mammals have demonstrated that free-ranging marine mammals often, but
not always (e.g., McKenna et al., 2015), engage in avoidance behavior
when surface vessels move toward them. It is not clear whether these
responses are caused by the physical presence of a surface vessel, the
underwater noise generated by the vessel, or an interaction between the
two (Amaral and Carlson, 2005; Au and Green, 2000; Bain et al., 2006;
Bauer 1986; Bejder et al., 1999; Bejder and Lusseau, 2008; Bejder et
al., 2009; Bryant et al., 1984; Corkeron, 1995; Erbe, 2002;
F[eacute]lix, 2001; Goodwin and Cotton, 2004; Lemon et al., 2006;
Lusseau, 2003; Lusseau, 2006; Magalhaes et al., 2002; Nowacek et al.,
2001; Richter et al., 2003; Scheidat et al., 2004; Simmonds, 2005;
Watkins, 1986; Williams et al., 2002; Wursig et al., 1998). Several
authors suggest that the noise generated during motion is probably an
important factor (Blane and Jaakson, 1994; Evans et al., 1992; Evans et
al., 1994). Water disturbance may also be a factor. These studies
suggest that the behavioral responses of marine mammals to surface
vessels are similar to their behavioral responses to predators.
Avoidance behavior is expected to be even stronger in the subset of
instances during which the Navy is conducting training or testing
activities using active sonar or explosives.
The marine mammals most vulnerable to vessel strikes are those that
spend extended periods of time at the surface in order to restore
oxygen levels within their tissues after deep dives (e.g., sperm
whales). In addition, some baleen whales seem generally unresponsive to
vessel sound, making them more susceptible to vessel collisions
(Nowacek et al., 2004). These species are primarily large, slow moving
whales.
Some researchers have suggested the relative risk of a vessel
strike can be assessed as a function of animal density and the
magnitude of vessel traffic (e.g., Fonnesbeck et al., 2008; Vanderlaan
et al., 2008). Differences among vessel types also influence the
probability of a vessel strike. The ability of any ship to detect a
marine mammal and avoid a collision depends on a variety of factors,
including environmental conditions, ship design, size, speed, and
ability and number of personnel observing, as well as the behavior of
the animal. Vessel speed, size, and mass are all important factors in
determining if injury or death of a marine mammal is likely due to a
vessel strike. For large vessels, speed and angle of approach can
influence the severity of a strike. For example, Vanderlaan and Taggart
(2007) found that between vessel speeds of 8.6 and 15 knots, the
probability that a vessel strike is lethal increases from 0.21 to 0.79.
Large whales also do not have to be at the water's surface to be
struck. Silber et al. (2010) found when a whale is below the surface
(about one to two times the vessel draft), under certain circumstances
(vessel speed and location of the whale relative to the ship's
centerline), there is likely to be a pronounced propeller suction
effect.

[[Page 33985]]

This suction effect may draw the whale into the hull of the ship,
increasing the probability of propeller strikes.
There are some key differences between the operation of military
and non-military vessels, which make the likelihood of a military
vessel striking a whale lower than some other vessels (e.g., commercial
merchant vessels). Key differences include:
Many military ships have their bridges positioned closer
to the bow, offering better visibility ahead of the ship (compared to a
commercial merchant vessel);
There are often aircraft associated with the training or
testing activity (which can serve as Lookouts), which can more readily
detect cetaceans in the vicinity of a vessel or ahead of a vessel's
present course before crew on the vessel would be able to detect them;
Military ships are generally more maneuverable than
commercial merchant vessels, and if cetaceans are spotted in the path
of the ship, could be capable of changing course more quickly;
The crew size on military vessels is generally larger than
merchant ships, allowing for stationing more trained Lookouts on the
bridge. At all times when Navy vessels are underway, trained Lookouts
and bridge navigation teams are used to detect objects on the surface
of the water ahead of the ship, including cetaceans. Additional
Lookouts, beyond those already stationed on the bridge and on
navigation teams, are positioned as Lookouts during some training
events; and
When submerged, submarines are generally slow moving (to
avoid detection) and therefore marine mammals at depth with a submarine
are likely able to avoid collision with the submarine. When a submarine
is transiting on the surface, there are Lookouts serving the same
function as they do on surface ships.
Vessel strike to marine mammals is not associated with any specific
training or testing activity but is rather an extremely limited and
sporadic, but possible, accidental result of Navy vessel movement
within the NWTT Study Area or while in transit.
Data from the ports of Vancouver, British Columbia; Seattle,
Washington; and Tacoma, Washington indicate there were more than 7,000
commercial vessel transits in 2017 associated with visits to just those
ports (The Northwest Seaport Alliance, 2018; Vancouver Fraser Port
Authority). This number of vessel transits does not account for other
vessel traffic in the Strait of Juan de Fuca or Puget Sound including
commercial ferries, tourist vessels, or recreational vessels.
Additional commercial traffic in the NWTT Study Area also includes
vessels transiting offshore along the Pacific coast, bypassing ports in
Canada and Washington; traffic associated with ports to the south along
the coast of Washington and in Oregon; and vessel traffic in Southeast
Alaska (Nuka Research & Planning Group, 2012). Navy vessel traffic
accounts for only a small portion of vessel activities in the NWTT
Study Area. The Navy has, in total, the following homeported
operational vessels: 2 Aircraft carriers, 6 destroyers, 14 submarines,
and 22 smaller security vessels with a combined annual total of 241
Navy vessel transits (see Appendix A (Navy Activities Descriptions) of
the 2019 DSEIS/OEIS for descriptions of the number of vessels used
during the various types of Navy's proposed activities). Activities
involving military vessel movement would be widely dispersed throughout
the NWTT Study Area.
Navy vessel strike records have been kept since 1995, and since
1995 there have been two recorded strikes of whales by Navy vessels (or
vessels being operated on behalf of the Navy) in the NWTT Study Area.
Neither strike was associated with training or testing activities. The
first strike occurred in 2012 by a Navy destroyer off the southern
coast of Oregon while in transit to San Diego. The whale was suspected
to be a minke whale due to the appearance and size (25 ft, dark with
white belly), however the Navy could not rule out the possibility that
it was a juvenile fin whale. The whale was observed swimming after the
strike and no blood or injury was sighted. The second strike occurred
in 2016 by a U.S. Coast Guard cutter operating on behalf of the Navy as
part of a Maritime Security Operation escort vessel in the Strait of
Juan de Fuca. The whale was positively identified as a humpback whale.
It was observed for 10 minutes post-collision and appeared normal at
the surface. There was no blood observed in the water and the whale
subsequently swam away.
In order to account for the potential risk from vessel movement
within the NWTT Study Area within the seven-year period in particular,
the Navy requested incidental takes based on probabilities derived from
a Poisson distribution using ship strike data between 2009-2018 in the
NWTT Study Area (the time period from when current mitigation measures
to reduce the likelihood of vessel strikes were instituted until the
Navy conducted the analysis for the Navy's application), as well as
historical at-sea days in the NWTT Study Area from 2009-2018 and
estimated potential at-sea days for the period from 2020 to 2027
covered by the requested regulations. This distribution predicted the
probabilities of a specific number of strikes (n = 0, 1, 2, etc.) over
the period from 2020 to 2027. The analysis for the period of 2020 to
2027 is described in detail in Chapter 6.6 (Vessel Strike Analysis) of
the Navy's rulemaking/LOA application.
For the same reasons listed above, describing why a Navy vessel
strike is comparatively unlikely, it is highly unlikely that a Navy
vessel would strike a whale, dolphin, porpoise, or pinniped without
detecting it and, accordingly, NMFS is confident that the Navy's
reported strikes are accurate and appropriate for use in the analysis.
Specifically, Navy ships have multiple Lookouts, including on the
forward part of the ship that can visually detect a hit animal, in the
unlikely event ship personnel do not feel the strike. Unlike the
situation for non-Navy ships engaged in commercial activities, NMFS and
the Navy have no evidence that the Navy has struck a whale and not
detected it. Navy's strict internal procedures and mitigation
requirements include reporting of any vessel strikes of marine mammals,
and the Navy's discipline, extensive training (not only for detecting
marine mammals, but for detecting and reporting any potential
navigational obstruction), and strict chain of command give NMFS a high
level of confidence that all strikes actually get reported.
The Navy used those two whale strikes in their calculations to
determine the number of strikes likely to result from their activities
and evaluated data beginning in 2009. The Navy's Marine Species
Awareness Training was first used in 2006 and was fully integrated
across the Navy in 2009, which is why the Navy uses 2009 as the date to
begin the analysis. The adoption of additional mitigation measures to
address ship strike also began in 2009, and will remain in place along
with additional mitigation measures during the seven years of this
rule. The probability analysis concluded that there was a 26 percent
chance that zero whales would be struck by Navy vessels over the seven-
year period, and a 35, 24, 11, and 4 percent chance that one, two,
three, or four whales, respectively, would be struck over the seven-
year period (with a 74 percent chance total that at least one whale
would be struck over the seven-year period). Therefore, the Navy
estimates, and NMFS agrees, that there is some probability that the
Navy could strike, and take by serious injury or

[[Page 33986]]

mortality, up to three large whales incidental to training and testing
activities within the NWTT Study Area over the course of the seven
years.
Small whales, delphinids, porpoises, and pinnipeds are not expected
to be struck by Navy vessels. In addition to the reasons listed above
that make it unlikely that the Navy will hit a large whale (more
maneuverable ships, larger crew, etc.), the following are the
additional reasons that vessel strike of dolphins, small whales,
porpoises, and pinnipeds is considered very unlikely. Dating back more
than 20 years and for as long as it has kept records, the Navy has no
records of individuals of these groups being struck by a vessel as a
result of Navy activities and, further, their smaller size and
maneuverability make a strike unlikely. Also, NMFS has never received
any reports from other authorized activities indicating that these
species have been struck by vessels. Worldwide ship strike records show
little evidence of strikes of these groups from the shipping sector and
larger vessels and the majority of the Navy's activities involving
faster-moving vessels (that could be considered more likely to hit a
marine mammal) are located in offshore areas where smaller delphinid,
porpoise, and pinniped densities are lower. Based on this information,
NMFS concurs with the Navy's assessment and recognizes the potential
for incidental take by vessel strike of large whales only (i.e., no
dolphins, small whales, porpoises, or pinnipeds) over the course of the
seven-year regulations from training and testing activities.
Taking into account the available information regarding how many of
any given stock could be struck and therefore should be authorized for
take, NMFS considered three factors in addition to those considered in
the Navy's request: (1) The relative likelihood of hitting one stock
versus another based on available strike data from all vessel types as
denoted in the SARs, (2) whether the Navy has ever definitively struck
an individual from a particular species or stock in the NWTT Study
Area, and if so, how many times, and (3) whether there are records that
an individual from a particular species or stock has been struck by any
vessel in the NWTT Study Area, and if so, how many times (based on ship
strike records provided by the NMFS West Coast Region in February
2020). To address number (1) above, NMFS compiled information from
NMFS' SARs on detected annual rates of large whale serious injury or
mortality (M/SI) from vessel collisions (Table 34). The annual rates of
large whale serious injury or mortality from vessel collisions from the
SARs help inform the relative susceptibility of large whale species to
vessel strike in NWTT Study Area as recorded systematically over the
last five years (the period used for the SARs). However, we note that
the SARs present strike data from the stock's entire range, which is
much larger than the NWTT Study Area, and available ship strike records
show that the majority of strikes that occur off the United States West
Coast occur in southern California. We summed the annual rates of
serious injury or mortality from vessel collisions as reported in the
SARs, then divided each species' annual rate by this sum to get the
proportion of strikes for each species/stock. To inform the likelihood
of striking a particular species of large whale, we multiplied the
proportion of striking each species by the probability of striking at
least one whale (i.e., 74 percent, as described by the Navy's
probability analysis above). We note that these probabilities vary from
year to year as the average annual mortality for a given five-year
window in the SAR changes; however, over the years and through changing
SARs, stocks tend to consistently maintain a relatively higher or
relatively lower likelihood of being struck (and we include the annual
averages from 2017 SARs in Table 34 to illustrate).
The probabilities calculated as described above are then considered
in combination with the information indicating the species that the
Navy has definitively hit in the NWTT Study Area since 1995 (since they
started tracking consistently) and the species that are known to have
been struck by any vessel (through regional stranding data) in the NWTT
Study Area. We also note that Rockwood et al. (2017) modeled the likely
vessel strike of blue whales, fin whales, and humpback whales on the
U.S. West Coast (discussed in more detail in the Serious Injury or
Mortality subsection of the Preliminary Analysis and Negligible Impact
Determination section), and those numbers help inform the relative
likelihood that the Navy will hit those stocks.
For each indicated stock, Table 34 includes the percent likelihood
of hitting an individual whale once based on SAR data, total strikes
from Navy vessels (from 1995), total strikes from any vessel (from 2000
from regional stranding data), and modeled vessel strikes from Rockwood
et al. (2017). The last column indicates the annual serious injury or
mortality proposed for authorization.

Table 34--Summary of Factors Considered in Determining the Number of Individuals in Each Stock Potentially Struck by a Vessel
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Percent
Annual rate Annual rate likelihood Total known
of M/SI of M/SI of hitting strikes in Total known Rockwood MMPA
from from individual OR, WA, navy et al. proposed Annual
ESA status Species Stock vessel vessel from northern CA strikes in (2017) authorized proposed
collision collision species/ (from 2000 NWTT study modeled takes authorized
(observed (observed stock once to present) area vessel (from the 3 take
from 2017 from 2019 (from 2019 \1\ strikes \5\ total)
SARs) Draft SARs) Draft SARs)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Listed............................... Blue whale.............. Eastern North Pacific.. 0 0.4 3.7 18 0 0
Fin whale............... Northeast Pacific...... 0.2 0.4 3.7 \2\ 10 2 0.29
CA/OR/WA............... 1.8 1.6 14.8 \2\ 10 43 2 0.29
Sei whale............... Eastern North Pacific.. 0 0.2 1.85 0 0
Humpback whale.......... CA/OR/WA (Mexico and 1.1 2.1 19.425 \3\ 4 \4\ 1 22 2 0.29
Central America DPS).
Sperm whale............. CA/OR/WA............... 0.2 0 0 3 1 0.14
Not Listed........................... Minke whale............. Alaska................. 0 0 0 0 0
CA/OR/WA............... 0 0 0 1 1 1 0.14
Gray whale.............. Eastern North Pacific.. 2 0.8 7.4 9 1 0.14
Humpback whale.......... Central North Pacific 2.6 2.5 23.125 \3\ 4 \4\ 1 2 0.29
(Hawaii DPS).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Only one ship strike was reported in California in the NWTT Study Area (which is limited to Humbolt and Del Norte Counties). This strike occurred in 2004 in Humbolt County and was not
identified to species.
\2\ A total of 10 fin whale strikes are reported in the regional stranding database, however no information on stock is provided. As these two stocks of fin whales are known to overlap
spatially and temporally in the NWTT Study Area, the 10 reported strikes could come from either stock or a combination of both stocks.
\3\ A total of 4 humpback whales strikes are reported in the regional stranding database, however no information on stock is provided. As these two stocks of humpback whales are known to
overlap spatially and temporally in the NWTT Study Area, the 4 reported strikes could come from either stock or a combination of both stocks.
\4\ One humpback whale was reported as struck by a U.S. Coast Guard cutter operating on behalf of the Navy, however it was not possible for the Navy to determine which stock this whale came
from. As these two stocks of humpback whales are known to overlap spatially and temporally in the NWTT Study Area, this whale could have come from either stock.

[[Page 33987]]

\5\ Rockwood et al. modeled likely annual vessel strikes off the West Coast for these three species only.

Accordingly, stocks that have no record of having been struck by
any vessel are considered unlikely to be struck by the Navy in the
seven-year period of the rule. Stocks that have never been struck by
the Navy, have rarely been struck by other vessels, and have a low
likelihood of being struck based on the SAR calculation and a low
relative abundance (Eastern North Pacific stock of blue whales, Eastern
North Pacific stock of sei whales, and Alaska stock of minke whales)
are also considered unlikely to be struck by the Navy during the seven-
year rule. This rules out all but seven stocks.
The two stocks of humpback whales (CA/OR/WA and Central North
Pacific) and two stocks of fin whales (CA/OR/WA and Northeast Pacific)
are known to overlap spatially and temporally in the NWTT Study Area,
and it is not possible to distinguish the difference between
individuals of these stocks based on visual sightings in the field. The
Navy has previously struck a humpback whale in the NWTT Study Area and
it is the second most common species struck by any vessel in the Study
Area based on stranding data. Based on the SAR data, the two stocks of
humpback whales also have the highest likelihood of being struck.
Though the Navy has not definitively struck a fin whale in the NWTT
Study Area (noting that the Navy could not rule out that the minke
whale strike could have been a juvenile fin whale), fin whales are the
most common species struck by any vessel in the Study Area based on
stranding data. Based on the SAR data, the CA/OR/WA stock has the third
highest likelihood of being struck. Based on all of these factors, it
is considered reasonably likely that humpback whales (from either the
CA/OR/WA or Central North Pacific stocks) could be struck twice and fin
whales (from either the CA/OR/WA or Northeast Pacific stocks) could be
struck twice during the seven-year rule.
Based on the SAR data, the CA/OR/WA stock of sperm whales and CA/
OR/WA stock of minke whales have a very low likelihood of being struck.
However, 3 sperm whales have been struck by non-Navy vessels in the
NWTT Study Area (in 2002, 2007, and 2012) and the Navy has previously
struck a minke whale in the NWTT Study Area. Therefore, we consider it
reasonable to predict that an individual from each of these stocks
could be struck by the Navy once during the seven-year rule. Finally,
based on stranding data, gray whales are the second most commonly
struck whale in the NWTT Study Area and the SAR data indicates that on
average, 0.8 whales from this stock are struck throughout the stock's
range each year. Based on these data, we consider it reasonable to
predict that an individual from the Eastern North Pacific stock of gray
whales could be struck by the Navy once during the seven-year rule.
In conclusion, although it is generally unlikely that any whales
will be struck in a year, based on the information and analysis above,
NMFS anticipates that no more than three whales have the potential to
be taken by serious injury or mortality over the seven-year period of
the rule. Of those three whales over the seven years, no more than two
may come from any of the following species/stocks: Fin whale (which may
come from either the Northeast Pacific or CA/OR/WA stock) and humpback
whale (which may come from either the Central North Pacific or CA/OR/WA
stock). Additionally, of those three whales over the seven years no
more than one may come from any of the following species/stocks: Sperm
whale (CA/OR/WA stock), minke whale (CA/OR/WA stock), and gray whale
(Eastern North Pacific stock). Accordingly, NMFS has evaluated under
the negligible impact standard the M/SI of 0.14 or 0.29 whales annually
from each of these species or stocks (i.e., 1 or 2 takes, respectively,
divided by seven years to get the annual number), along with the
expected incidental takes by harassment. We do not anticipate, nor
propose to authorize, ship strike takes to blue whales (Eastern North
Pacific stock), minke whales (Alaska stock), or sei whales (Eastern
North Pacific stock).

Proposed Mitigation Measures

Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the
permissible methods of taking pursuant to the activity, and other means
of effecting the least practicable adverse impact on the species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance, and on the
availability of the species or stocks for subsistence uses (``least
practicable adverse impact''). NMFS does not have a regulatory
definition for least practicable adverse impact. The 2004 NDAA amended
the MMPA as it relates to military readiness activities and the
incidental take authorization process such that a determination of
``least practicable adverse impact'' shall include consideration of
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
In Conservation Council for Hawaii v. National Marine Fisheries
Service, 97 F. Supp. 3d 1210, 1229 (D. Haw. 2015), the Court stated
that NMFS ``appear[s] to think [it] satisf[ies] the statutory `least
practicable adverse impact' requirement with a `negligible impact'
finding.'' More recently, expressing similar concerns in a challenge to
a U.S. Navy Surveillance Towed Array Sensor System Low Frequency Active
Sonar (SURTASS LFA) incidental take rule (77 FR 50290), the Ninth
Circuit Court of Appeals in Natural Resources Defense Council (NRDC) v.
Pritzker, 828 F.3d 1125, 1134 (9th Cir. 2016), stated, ``[c]ompliance
with the `negligible impact' requirement does not mean there [is]
compliance with the `least practicable adverse impact' standard.'' As
the Ninth Circuit noted in its opinion, however, the Court was
interpreting the statute without the benefit of NMFS' formal
interpretation. We state here explicitly that NMFS is in full agreement
that the ``negligible impact'' and ``least practicable adverse impact''
requirements are distinct, even though both statutory standards refer
to species and stocks. With that in mind, we provide further
explanation of our interpretation of least practicable adverse impact,
and explain what distinguishes it from the negligible impact standard.
This discussion is consistent with previous rules we have published,
such as the Navy's Hawaii-Southern California Training and Testing
(HSTT) rule (83 FR 66846; December 27, 2018), Atlantic Fleet Training
and Testing (AFTT) rule (84 FR 70712; December 23, 2019), and Mariana
Islands Training and Testing (MITT) proposed rule (85 FR 5782; January
31, 2020).
Before NMFS can issue incidental take regulations under section
101(a)(5)(A) of the MMPA, it must make a finding that the total taking
will have a ``negligible impact'' on the affected ``species or stocks''
of marine mammals. NMFS' and U.S. Fish and Wildlife Service's
implementing regulations for section 101(a)(5) both define ``negligible
impact'' as an impact resulting from the specified activity that cannot
be reasonably expected to, and is not reasonably likely to, adversely
affect the species or stock through effects on annual rates of
recruitment or survival (50 CFR 216.103 and 50 CFR 18.27(c)).
Recruitment (i.e., reproduction) and survival rates are used to
determine

[[Page 33988]]

population growth rates \3\ and, therefore are considered in evaluating
population level impacts.
---------------------------------------------------------------------------

\3\ A growth rate can be positive, negative, or flat.
---------------------------------------------------------------------------

As stated in the preamble to the proposed rule for the MMPA
incidental take implementing regulations, not every population-level
impact violates the negligible impact requirement. The negligible
impact standard does not require a finding that the anticipated take
will have ``no effect'' on population numbers or growth rates: The
statutory standard does not require that the same recovery rate be
maintained, rather that no significant effect on annual rates of
recruitment or survival occurs. The key factor is the significance of
the level of impact on rates of recruitment or survival. (54 FR 40338,
40341-42; September 29, 1989).
While some level of impact on population numbers or growth rates of
a species or stock may occur and still satisfy the negligible impact
requirement--even without consideration of mitigation--the least
practicable adverse impact provision separately requires NMFS to
prescribe means of effecting the least practicable adverse impact on
such species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, 50 CFR
216.102(b), which are typically identified as mitigation measures.\4\
---------------------------------------------------------------------------

\4\ For purposes of this discussion, we omit reference to the
language in the standard for least practicable adverse impact that
says we also must mitigate for subsistence impacts because they are
not at issue in this rule.
---------------------------------------------------------------------------

The negligible impact and least practicable adverse impact
standards in the MMPA both call for evaluation at the level of the
``species or stock.'' The MMPA does not define the term ``species.''
However, Merriam-Webster Dictionary defines ``species'' to include
``related organisms or populations potentially capable of
interbreeding.'' See www.merriam-webster.com/dictionary/species
(emphasis added). Section 3(11) of the MMPA defines ``stock'' as a
group of marine mammals of the same species or smaller taxa in a common
spatial arrangement that interbreed when mature. The definition of
``population'' is a group of interbreeding organisms that represents
the level of organization at which speciation begins. www.merriam-webster.com/dictionary/population. The definition of ``population'' is
strikingly similar to the MMPA's definition of ``stock,'' with both
involving groups of individuals that belong to the same species and
located in a manner that allows for interbreeding. In fact under MMPA
section 3(11), the term ``stock'' in the MMPA is interchangeable with
the statutory term ``population stock.'' Both the negligible impact
standard and the least practicable adverse impact standard call for
evaluation at the level of the species or stock, and the terms
``species'' and ``stock'' both relate to populations; therefore, it is
appropriate to view both the negligible impact standard and the least
practicable adverse impact standard as having a population-level focus.
This interpretation is consistent with Congress' statutory findings
for enacting the MMPA, nearly all of which are most applicable at the
species or stock (i.e., population) level. See MMPA section 2 (finding
that it is species and population stocks that are or may be in danger
of extinction or depletion; that it is species and population stocks
that should not diminish beyond being significant functioning elements
of their ecosystems; and that it is species and population stocks that
should not be permitted to diminish below their optimum sustainable
population level). Annual rates of recruitment (i.e., reproduction) and
survival are the key biological metrics used in the evaluation of
population-level impacts, and accordingly these same metrics are also
used in the evaluation of population level impacts for the least
practicable adverse impact standard.
Recognizing this common focus of the least practicable adverse
impact and negligible impact provisions on the ``species or stock''
does not mean we conflate the two standards; despite some common
statutory language, we recognize the two provisions are different and
have different functions. First, a negligible impact finding is
required before NMFS can issue an incidental take authorization.
Although it is acceptable to use the mitigation measures to reach a
negligible impact finding (see 50 CFR 216.104(c)), no amount of
mitigation can enable NMFS to issue an incidental take authorization
for an activity that still would not meet the negligible impact
standard. Moreover, even where NMFS can reach a negligible impact
finding--which we emphasize does allow for the possibility of some
``negligible'' population-level impact--the agency must still prescribe
measures that will affect the least practicable amount of adverse
impact upon the affected species or stock.
Section 101(a)(5)(A)(i)(II) requires NMFS to issue, in conjunction
with its authorization, binding--and enforceable--restrictions (in the
form of regulations) setting forth how the activity must be conducted,
thus ensuring the activity has the ``least practicable adverse impact''
on the affected species or stocks. In situations where mitigation is
specifically needed to reach a negligible impact determination, section
101(a)(5)(A)(i)(II) also provides a mechanism for ensuring compliance
with the ``negligible impact'' requirement. Finally, the least
practicable adverse impact standard also requires consideration of
measures for marine mammal habitat, with particular attention to
rookeries, mating grounds, and other areas of similar significance, and
for subsistence impacts, whereas the negligible impact standard is
concerned solely with conclusions about the impact of an activity on
annual rates of recruitment and survival.\5\ In NRDC v. Pritzker, the
Court stated, ``[t]he statute is properly read to mean that even if
population levels are not threatened significantly, still the agency
must adopt mitigation measures aimed at protecting marine mammals to
the greatest extent practicable in light of military readiness needs.''
Pritzker at 1134 (emphases added). This statement is consistent with
our understanding stated above that even when the effects of an action
satisfy the negligible impact standard (i.e., in the Court's words,
``population levels are not threatened significantly''), still the
agency must prescribe mitigation under the least practicable adverse
impact standard. However, as the statute indicates, the focus of both
standards is ultimately the impact on the affected ``species or
stock,'' and not solely focused on or directed at the impact on
individual marine mammals.
---------------------------------------------------------------------------

\5\ Outside of the military readiness context, mitigation may
also be appropriate to ensure compliance with the ``small numbers''
language in MMPA sections 101(a)(5)(A) and (D).
---------------------------------------------------------------------------

We have carefully reviewed and considered the Ninth Circuit's
opinion in NRDC v. Pritzker in its entirety. While the Court's
reference to ``marine mammals'' rather than ``marine mammal species or
stocks'' in the italicized language above might be construed as holding
that the least practicable adverse impact standard applies at the
individual ``marine mammal'' level, i.e., that NMFS must require
mitigation to minimize impacts to each individual marine mammal unless
impracticable, we believe such an interpretation reflects an incomplete
appreciation of the Court's holding. In our view, the opinion as a
whole turned on the Court's determination that NMFS had not given
separate and independent meaning to the least practicable adverse
impact standard apart from the negligible impact standard, and further,
that the Court's use of the term ``marine mammals'' was not addressing
the

[[Page 33989]]

question of whether the standard applies to individual animals as
opposed to the species or stock as a whole. We recognize that while
consideration of mitigation can play a role in a negligible impact
determination, consideration of mitigation measures extends beyond that
analysis. In evaluating what mitigation measures are appropriate, NMFS
considers the potential impacts of the Specified Activities, the
availability of measures to minimize those potential impacts, and the
practicability of implementing those measures, as we describe below.

Implementation of Least Practicable Adverse Impact Standard

Given the NRDC v. Pritzker decision, we discuss here how we
determine whether a measure or set of measures meets the ``least
practicable adverse impact'' standard. Our separate analysis of whether
the take anticipated to result from Navy's activities meets the
``negligible impact'' standard appears in the Preliminary Analysis and
Negligible Impact Determination section below.
Our evaluation of potential mitigation measures includes
consideration of two primary factors:
(1) The manner in which, and the degree to which, implementation of
the potential measure(s) is expected to reduce adverse impacts to
marine mammal species or stocks, their habitat, and their availability
for subsistence uses (where relevant). This analysis considers such
things as the nature of the potential adverse impact (such as
likelihood, scope, and range), the likelihood that the measure will be
effective if implemented, and the likelihood of successful
implementation; and
(2) The practicability of the measures for applicant
implementation. Practicability of implementation may consider such
things as cost, impact on activities, and, in the case of a military
readiness activity, specifically considers personnel safety,
practicality of implementation, and impact on the effectiveness of the
military readiness activity.
While the language of the least practicable adverse impact standard
calls for minimizing impacts to affected species or stocks, we
recognize that the reduction of impacts to those species or stocks
accrues through the application of mitigation measures that limit
impacts to individual animals. Accordingly, NMFS' analysis focuses on
measures that are designed to avoid or minimize impacts on individual
marine mammals that are likely to increase the probability or severity
of population-level effects.
While direct evidence of impacts to species or stocks from a
specified activity is rarely available, and additional study is still
needed to understand how specific disturbance events affect the fitness
of individuals of certain species, there have been improvements in
understanding the process by which disturbance effects are translated
to the population. With recent scientific advancements (both marine
mammal energetic research and the development of energetic frameworks),
the relative likelihood or degree of impacts on species or stocks may
often be inferred given a detailed understanding of the activity, the
environment, and the affected species or stocks--and the best available
science has been used here. This same information is used in the
development of mitigation measures and helps us understand how
mitigation measures contribute to lessening effects (or the risk
thereof) to species or stocks. We also acknowledge that there is always
the potential that new information, or a new recommendation could
become available in the future and necessitate reevaluation of
mitigation measures (which may be addressed through adaptive
management) to see if further reductions of population impacts are
possible and practicable.
In the evaluation of specific measures, the details of the
specified activity will necessarily inform each of the two primary
factors discussed above (expected reduction of impacts and
practicability), and are carefully considered to determine the types of
mitigation that are appropriate under the least practicable adverse
impact standard. Analysis of how a potential mitigation measure may
reduce adverse impacts on a marine mammal stock or species,
consideration of personnel safety, practicality of implementation, and
consideration of the impact on effectiveness of military readiness
activities are not issues that can be meaningfully evaluated through a
yes/no lens. The manner in which, and the degree to which,
implementation of a measure is expected to reduce impacts, as well as
its practicability in terms of these considerations, can vary widely.
For example, a time/area restriction could be of very high value for
decreasing population-level impacts (e.g., avoiding disturbance of
feeding females in an area of established biological importance) or it
could be of lower value (e.g., decreased disturbance in an area of high
productivity but of less biological importance). Regarding
practicability, a measure might involve restrictions in an area or time
that impede the Navy's ability to certify a strike group (higher impact
on mission effectiveness), or it could mean delaying a small in-port
training event by 30 minutes to avoid exposure of a marine mammal to
injurious levels of sound (lower impact). A responsible evaluation of
``least practicable adverse impact'' will consider the factors along
these realistic scales. Accordingly, the greater the likelihood that a
measure will contribute to reducing the probability or severity of
adverse impacts to the species or stock or its habitat, the greater the
weight that measure is given when considered in combination with
practicability to determine the appropriateness of the mitigation
measure, and vice versa. We discuss consideration of these factors in
greater detail below.
1. Reduction of adverse impacts to marine mammal species or stocks
and their habitat.\6\ The emphasis given to a measure's ability to
reduce the impacts on a species or stock considers the degree,
likelihood, and context of the anticipated reduction of impacts to
individuals (and how many individuals) as well as the status of the
species or stock.
---------------------------------------------------------------------------

\6\ We recognize the least practicable adverse impact standard
requires consideration of measures that will address minimizing
impacts on the availability of the species or stocks for subsistence
uses where relevant. Because subsistence uses are not implicated for
this action, we do not discuss them. However, a similar framework
would apply for evaluating those measures, taking into account the
MMPA's directive that we make a finding of no unmitigable adverse
impact on the availability of the species or stocks for taking for
subsistence, and the relevant implementing regulations.
---------------------------------------------------------------------------

The ultimate impact on any individual from a disturbance event
(which informs the likelihood of adverse species- or stock-level
effects) is dependent on the circumstances and associated contextual
factors, such as duration of exposure to stressors. Though any proposed
mitigation needs to be evaluated in the context of the specific
activity and the species or stocks affected, measures with the
following types of effects have greater value in reducing the
likelihood or severity of adverse species- or stock-level impacts:
Avoiding or minimizing injury or mortality; limiting interruption of
known feeding, breeding, mother/young, or resting behaviors; minimizing
the abandonment of important habitat (temporally and spatially);
minimizing the number of individuals subjected to these types of
disruptions; and limiting degradation of habitat. Mitigating these
types of effects is intended to reduce the likelihood that the activity
will result in energetic or other types of impacts that

[[Page 33990]]

are more likely to result in reduced reproductive success or
survivorship. It is also important to consider the degree of impacts
that are expected in the absence of mitigation in order to assess the
added value of any potential measures. Finally, because the least
practicable adverse impact standard gives NMFS discretion to weigh a
variety of factors when determining appropriate mitigation measures and
because the focus of the standard is on reducing impacts at the species
or stock level, the least practicable adverse impact standard does not
compel mitigation for every kind of take, or every individual taken, if
that mitigation is unlikely to meaningfully contribute to the reduction
of adverse impacts on the species or stock and its habitat, even when
practicable for implementation by the applicant.
The status of the species or stock is also relevant in evaluating
the appropriateness of potential mitigation measures in the context of
least practicable adverse impact. The following are examples of factors
that may (either alone, or in combination) result in greater emphasis
on the importance of a mitigation measure in reducing impacts on a
species or stock: The stock is known to be decreasing or status is
unknown, but believed to be declining; the known annual mortality (from
any source) is approaching or exceeding the potential biological
removal (PBR) level (as defined in MMPA section 3(20)); the affected
species or stock is a small, resident population; or the stock is
involved in a UME or has other known vulnerabilities, such as
recovering from an oil spill.
Habitat mitigation, particularly as it relates to rookeries, mating
grounds, and areas of similar significance, is also relevant to
achieving the standard and can include measures such as reducing
impacts of the activity on known prey utilized in the activity area or
reducing impacts on physical habitat. As with species- or stock-related
mitigation, the emphasis given to a measure's ability to reduce impacts
on a species or stock's habitat considers the degree, likelihood, and
context of the anticipated reduction of impacts to habitat. Because
habitat value is informed by marine mammal presence and use, in some
cases there may be overlap in measures for the species or stock and for
use of habitat.
We consider available information indicating the likelihood of any
measure to accomplish its objective. If evidence shows that a measure
has not typically been effective nor successful, then either that
measure should be modified or the potential value of the measure to
reduce effects should be lowered.
2. Practicability. Factors considered may include cost, impact on
activities, and, in the case of a military readiness activity, will
include personnel safety, practicality of implementation, and impact on
the effectiveness of the military readiness activity (see MMPA section
101(a)(5)(A)(ii)).

Assessment of Mitigation Measures for NWTT Study Area

NMFS has fully reviewed the specified activities and the mitigation
measures included in the Navy's rulemaking/LOA application and the 2019
NWTT DSEIS/OEIS to determine if the mitigation measures would result in
the least practicable adverse impact on marine mammals and their
habitat. NMFS worked with the Navy in the development of the Navy's
initially proposed measures, which are informed by years of
implementation and monitoring. A complete discussion of the Navy's
evaluation process used to develop, assess, and select mitigation
measures, which was informed by input from NMFS, can be found in
Chapter 5 (Mitigation) and Appendix K (Geographic Mitigation
Assessment) of the 2019 NWTT DSEIS/OEIS. The process described in
Chapter 5 (Mitigation) and Appendix K (Geographic Mitigation
Assessment) of the 2019 NWTT DSEIS/OEIS robustly supported NMFS'
independent evaluation of whether the mitigation measures would meet
the least practicable adverse impact standard. The Navy would be
required to implement the mitigation measures identified in this rule
for the full seven years to avoid or reduce potential impacts from
acoustic, explosive, and physical disturbance and strike stressors.
As a general matter, where an applicant proposes measures that are
likely to reduce impacts to marine mammals, the fact that they are
included in the application indicates that the measures are
practicable, and it is not necessary for NMFS to conduct a detailed
analysis of the measures the applicant proposed (rather, they are
simply included). However, it is still necessary for NMFS to consider
whether there are additional practicable measures that would
meaningfully reduce the probability or severity of impacts that could
affect reproductive success or survivorship.
Overall the Navy has agreed to procedural mitigation measures that
would reduce the probability and/or severity of impacts expected to
result from acute exposure to acoustic sources or explosives, ship
strike, and impacts to marine mammal habitat. Specifically, the Navy
would use a combination of delayed starts, powerdowns, and shutdowns to
avoid mortality or serious injury, minimize the likelihood or severity
of PTS or other injury, and reduce instances of TTS or more severe
behavioral disruption caused by acoustic sources or explosives. The
Navy would also implement multiple time/area restrictions that would
reduce take of marine mammals in areas or at times where they are known
to engage in important behaviors, such as calving, where the disruption
of those behaviors would have a higher probability of resulting in
impacts on reproduction or survival of individuals that could lead to
population-level impacts.
The Navy assessed the practicability of the proposed measures in
the context of personnel safety, practicality of implementation, and
their impacts on the Navy's ability to meet their Title 10 requirements
and found that the measures are supportable. As described in more
detail below, NMFS has independently evaluated the measures the Navy
proposed in the manner described earlier in this section (i.e., in
consideration of their ability to reduce adverse impacts on marine
mammal species and their habitat and their practicability for
implementation). We have determined that the measures will
significantly and adequately reduce impacts on the affected marine
mammal species and stocks and their habitat and, further, be
practicable for Navy implementation. Therefore, the mitigation measures
assure that the Navy's activities will have the least practicable
adverse impact on the species or stocks and their habitat.
The Navy also evaluated numerous measures in the 2019 NWTT DSEIS/
OEIS that were not included in the Navy's rulemaking/LOA application,
and NMFS independently reviewed and preliminarily concurs with the
Navy's analysis that their inclusion was not appropriate under the
least practicable adverse impact standard based on our assessment. The
Navy considered these additional potential mitigation measures in two
groups. First, Chapter 5 (Mitigation) of the 2019 NWTT DSEIS/OEIS, in
the Measures Considered but Eliminated section, includes an analysis of
an array of different types of mitigation that have been recommended
over the years by non-governmental organizations or the public, through
scoping or public comment on environmental compliance documents.
Appendix K (Geographic Mitigation Assessment) of the 2019 NWTT DSEIS/
OEIS includes an in-depth analysis of

[[Page 33991]]

time/area restrictions that have been recommended over time or
previously implemented as a result of litigation (outside of the NWTT
Study Area). As described in Chapter 5 (Mitigation) of the 2019 NWTT
DSEIS/OEIS, commenters sometimes recommend that the Navy reduce its
overall amount of training, reduce explosive use, modify its sound
sources, completely replace live training with computer simulation, or
include time of day restrictions. Many of these mitigation measures
could potentially reduce the number of marine mammals taken, via direct
reduction of the activities or amount of sound energy put in the water.
However, as described in Chapter 5 (Mitigation) of the 2019 NWTT DSEIS/
OEIS, the Navy needs to train and test in the conditions in which it
fights--and these types of modifications fundamentally change the
activity in a manner that would not support the purpose and need for
the training and testing (i.e., are entirely impracticable) and
therefore are not considered further. NMFS finds the Navy's explanation
for why adoption of these recommendations would unacceptably undermine
the purpose of the testing and training persuasive. After independent
review, NMFS finds Navy's judgment on the impacts of potential
mitigation measures to personnel safety, practicality of
implementation, and the effectiveness of training and testing within
the NWTT Study Area persuasive, and for these reasons, NMFS finds that
these measures do not meet the least practicable adverse impact
standard because they are not practicable.
Second, in Chapter 5 (Mitigation) of the 2019 NWTT DSEIS/OEIS, the
Navy evaluated additional potential procedural mitigation measures,
including increased mitigation zones, ramp-up measures, additional
passive acoustic and visual monitoring, and decreased vessel speeds.
Some of these measures have the potential to incrementally reduce take
to some degree in certain circumstances, though the degree to which
this would occur is typically low or uncertain. However, as described
in the Navy's analysis, the measures would have significant direct
negative effects on mission effectiveness and are considered
impracticable (see Chapter 5 Mitigation of 2019 NWTT DSEIS/OEIS). NMFS
independently reviewed the Navy's evaluation and concurs with this
assessment, which supports NMFS' preliminary findings that the
impracticability of this additional mitigation would greatly outweigh
any potential minor reduction in marine mammal impacts that might
result; therefore, these additional mitigation measures are not
warranted.
Last, Appendix K (Geographic Mitigation Assessment) of the 2019
NWTT DSEIS/OEIS describes a comprehensive method for analyzing
potential geographic mitigation that includes consideration of both a
biological assessment of how the potential time/area limitation would
benefit the species and its habitat (e.g., is a key area of biological
importance or would result in avoidance or reduction of impacts) in the
context of the stressors of concern in the specific area and an
operational assessment of the practicability of implementation (e.g.,
including an assessment of the specific importance of that area for
training, considering proximity to training ranges and emergency
landing fields and other issues). For most of the areas that were
considered in the 2019 NWTT DSEIS/OEIS but not included in this rule,
the Navy found that the mitigation was not warranted because the
anticipated reduction of adverse impacts on marine mammal species and
their habitat was not sufficient to offset the impracticability of
implementation. In some cases potential benefits to marine mammals were
non-existent, while in others the consequences on mission effectiveness
were too great.
NMFS has reviewed the Navy's analysis in Chapter 5 Mitigation and
Appendix K Geographic Mitigation Assessment of the 2019 NWTT DSEIS/
OEIS, which considers the same factors that NMFS considers to satisfy
the least practicable adverse impact standard, and concurs with the
analysis and conclusions. Therefore, NMFS is not proposing to include
any of the measures that the Navy ruled out in the 2019 NWTT DSEIS/
OEIS. Below are the mitigation measures that NMFS determined will
ensure the least practicable adverse impact on all affected species and
their habitat, including the specific considerations for military
readiness activities. The following sections describe the mitigation
measures that would be implemented in association with the training and
testing activities analyzed in this document. The mitigation measures
are organized into two categories: Procedural mitigation and mitigation
areas.

Procedural Mitigation

Procedural mitigation is mitigation that the Navy would implement
whenever and wherever an applicable training or testing activity takes
place within the NWTT Study Area. The Navy customizes procedural
mitigation for each applicable activity category or stressor.
Procedural mitigation generally involves: (1) The use of one or more
trained Lookouts to diligently observe for specific biological
resources (including marine mammals) within a mitigation zone, (2)
requirements for Lookouts to immediately communicate sightings of
specific biological resources to the appropriate watch station for
information dissemination, and (3) requirements for the watch station
to implement mitigation (e.g., halt an activity) until certain
recommencement conditions have been met. The first procedural
mitigation (Table 35) is designed to aid Lookouts and other applicable
Navy personnel with their observation, environmental compliance, and
reporting responsibilities. The remainder of the procedural mitigation
measures (Tables 36 through 49) are organized by stressor type and
activity category and include acoustic stressors (i.e., active sonar,
weapons firing noise), explosive stressors (i.e., sonobuoys, torpedoes,
medium-caliber and large-caliber projectiles, missiles, bombs, mine
counter-measure and neutralization activities, mine neutralization
involving Navy divers), and physical disturbance and strike stressors
(i.e., vessel movement, towed in-water devices, small-, medium-, and
large-caliber non-explosive practice munitions, non-explosive missiles,
non-explosive bombs and mine shapes).

Table 35--Procedural Mitigation for Environmental Awareness and
Education
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
All training and testing activities, as applicable.
Mitigation Requirements:
Appropriate personnel (including civilian personnel)
involved in mitigation and training or testing activity reporting
under the specified activities will complete one or more modules of
the U.S. Navy Afloat Environmental Compliance Training Series, as
identified in their career path training plan. Modules include:

[[Page 33992]]

--Introduction to the U.S. Navy Afloat Environmental Compliance
Training Series. The introductory module provides information
on environmental laws (e.g., ESA, MMPA) and the corresponding
responsibilities that are relevant to Navy training and testing
activities. The material explains why environmental compliance
is important in supporting the Navy's commitment to
environmental stewardship.
--Marine Species Awareness Training. All bridge watch personnel,
Commanding Officers, Executive Officers, maritime patrol
aircraft aircrews, anti[hyphen]submarine warfare and mine
warfare rotary-wing aircrews, Lookouts, and equivalent civilian
personnel must successfully complete the Marine Species
Awareness Training prior to standing watch or serving as a
Lookout. The Marine Species Awareness Training provides
information on sighting cues, visual observation tools and
techniques, and sighting notification procedures. Navy
biologists developed Marine Species Awareness Training to
improve the effectiveness of visual observations for biological
resources, focusing on marine mammals and sea turtles, and
including floating vegetation, jellyfish aggregations, and
flocks of seabirds.
--U.S. Navy Protective Measures Assessment Protocol. This module
provides the necessary instruction for accessing mitigation
requirements during the event planning phase using the
Protective Measures Assessment Protocol software tool.
--U.S. Navy Sonar Positional Reporting System and Marine Mammal
Incident Reporting. This module provides instruction on the
procedures and activity reporting requirements for the Sonar
Positional Reporting System and marine mammal incident
reporting.
------------------------------------------------------------------------

Procedural Mitigation for Acoustic Stressors
Mitigation measures for acoustic stressors are provided in Tables
36 and 37.
Procedural Mitigation for Active Sonar
Procedural mitigation for active sonar is described in Table 36
below.

Table 36--Procedural Mitigation for Active Sonar
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Low-frequency active sonar, mid-frequency active sonar,
high-frequency active sonar:
--For vessel-based active sonar activities, mitigation applies
only to sources that are positively controlled and deployed
from manned surface vessels (e.g., sonar sources towed from
manned surface platforms).
--For aircraft-based active sonar activities, mitigation applies
only to sources that are positively controlled and deployed
from manned aircraft that do not operate at high altitudes
(e.g., rotary-wing aircraft). Mitigation does not apply to
active sonar sources deployed from unmanned aerial systems or
aircraft operating at high altitudes (e.g., maritime patrol
aircraft).
Number of Lookouts and Observation Platform:
Hull-mounted sources:
--1 Lookout: Platforms with space or manning restrictions while
underway (at the forward part of a small boat or ship) and
platforms using active sonar while moored or at anchor
(including pierside).
--2 Lookouts: Platforms without space or manning restrictions
while underway (at the forward part of the ship).
Sources that are not hull-mounted:
--1 Lookout on the ship or aircraft conducting the activity.
Mitigation Requirements:
Mitigation zones:
--1,000 yd power down, 500 yd power down, and 200 yd or 100 yd
shut down for low-frequency active sonar >=200 decibels (dB)
and hull-mounted mid-frequency active sonar.
--200 yd or 100 yd shut down for low-frequency active sonar <200
dB, mid-frequency active sonar sources that are not hull-
mounted, and high-frequency active sonar.
Prior to the initial start of the activity (e.g., when
maneuvering on station):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of active sonar transmission.
During the activity:
--Low-frequency active sonar >=200 decibels (dB) and hull-
mounted mid-frequency active sonar: Observe the mitigation zone
for marine mammals; power down active sonar transmission by 6
dB if a marine mammal is observed within 1,000 yd of the sonar
source; power down an additional 4 dB (10 dB total) if a marine
mammal is observed within 500 yd; cease transmission if a
cetacean in the NWTT Offshore Area, NWTT Inland Area, or
Western Behm Canal is observed within 200 yd; cease
transmission if a pinniped in the NWTT Offshore Area or Western
Behm Canal is observed within 200 yd and cease transmission if
a pinniped in NWTT Inland Waters is observed within 100 yd
(except if hauled out on, or in the water near, man-made
structures and vessels).
--Low-frequency active sonar <200 dB, mid-frequency active sonar
sources that are not hull-mounted, and high-frequency active
sonar: Observe the mitigation zone for marine mammals; cease
transmission if a cetacean or pinniped in the NWTT Offshore
Area or Western Behm Canal is observed within 200 yd of the
sonar source; cease transmission if a pinniped in NWTT Inland
Waters is observed within 100 yd (except if hauled out on, or
in the water near, man-made structures and vessels).
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:

[[Page 33993]]

--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
or powering up active sonar transmission) until one of the
following conditions has been met: (1) The animal is observed
exiting the mitigation zone; (2) the animal is thought to have
exited the mitigation zone based on a determination of its
course, speed, and movement relative to the sonar source; (3)
the mitigation zone has been clear from any additional
sightings for 10 minutes for aircraft-deployed sonar sources or
30 minutes for vessel-deployed sonar sources; (4) for mobile
activities, the active sonar source has transited a distance
equal to double that of the mitigation zone size beyond the
location of the last sighting; or (5) for activities using hull-
mounted sonar, the Lookout concludes that dolphins are
deliberately closing in on the ship to ride the ship's bow
wave, and are therefore out of the main transmission axis of
the sonar (and there are no other marine mammal sightings
within the mitigation zone).
------------------------------------------------------------------------

Procedural Mitigation for Weapons Firing Noise
Procedural mitigation for weapons firing noise is described in
Table 37 below.

Table 37--Procedural Mitigation for Weapons Firing Noise
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Weapons firing noise associated with large-caliber gunnery
activities.
Number of Lookouts and Observation Platform:
1 Lookout positioned on the ship conducting the firing;
--Depending on the activity, the Lookout could be the same one
described in Table 40 for Explosive Medium-Caliber and Large-
Caliber Projectiles or Table 47 for Small-, Medium-, and Large-
Caliber Non-Explosive Practice Munitions.
Mitigation Requirements:
Mitigation zone:
--30[deg] on either side of the firing line out to 70 yd from
the muzzle of the weapon being fired.
Prior to the initial start of the activity:
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of weapons firing.
During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease weapons firing.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
weapons firing) until one of the following conditions has been
met: (1) The animal is observed exiting the mitigation zone;
(2) the animal is thought to have exited the mitigation zone
based on a determination of its course, speed, and movement
relative to the firing ship; (3) the mitigation zone has been
clear from any additional sightings for 30 minutes; or (4) for
mobile activities, the firing ship has transited a distance
equal to double that of the mitigation zone size beyond the
location of the last sighting.
------------------------------------------------------------------------

Procedural Mitigation for Explosive Stressors
Mitigation measures for explosive stressors are provided in Tables
38 through 44.
Procedural Mitigation for Explosive Sonobuoys
Procedural mitigation for explosive sonobuoys is described in Table
38 below.

Table 38--Procedural Mitigation for Explosive Sonobuoys
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive sonobuoys.
Number of Lookouts and Observation Platform:
1 Lookout positioned in an aircraft or on a small boat.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) will support observing the mitigation zone for marine
mammals while performing their regular duties.
Mitigation Requirements:
Mitigation zone:
--600 yd. around an explosive sonobuoy.
Prior to the initial start of the activity (e.g., during
deployment of a sonobuoy field, which typically lasts 20-30
minutes):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Conduct passive acoustic monitoring for marine mammals; use
information from detections to assist visual observations.
--Visually observe the mitigation zone for marine mammals; if
observed, relocate or delay the start of sonobuoy or source/
receiver pair detonations.

[[Page 33994]]

During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease sonobuoy or source/receiver pair detonations.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
detonations) until one of the following conditions has been
met: (1) The animal is observed exiting the mitigation zone;
(2) the animal is thought to have exited the mitigation zone
based on a determination of its course, speed, and movement
relative to the sonobuoy; or (3) the mitigation zone has been
clear from any additional sightings for 10 minutes when the
activity involves aircraft that have fuel constraints, or 30
minutes when the activity involves aircraft that are not
typically fuel constrained.
After completion of the activity (e.g., prior to
maneuvering off station):
--When practical (e.g., when platforms are not constrained by
fuel restrictions or mission-essential follow-on commitments),
observe for marine mammals in the vicinity of where detonations
occurred; if any injured or dead marine mammals are observed,
follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets will assist in the
visual observation of the area where detonations occurred.
------------------------------------------------------------------------

Procedural Mitigation for Explosive Torpedoes
Procedural mitigation for explosive torpedoes is described in Table
39 below.

Table 39--Procedural Mitigation for Explosive Torpedoes
------------------------------------------------------------------------
Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive torpedoes.
Number of Lookouts and Observation Platform:
1 Lookout positioned in an aircraft.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) will support observing the mitigation zone for marine
mammals while performing their regular duties.
Mitigation Requirements:
Mitigation zone:
--2,100 yd around the intended impact location.
Prior to the initial start of the activity (e.g., during
deployment of the target):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Conduct passive acoustic monitoring for marine mammals; use
information from detections to assist visual observations.
--Visually observe the mitigation zone for marine mammals; if
observed, relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease firing.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
firing) until one of the following conditions has been met: (1)
The animal is observed exiting the mitigation zone; (2) the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to
the intended impact location; or (3) the mitigation zone has
been clear from any additional sightings for 10 minutes when
the activity involves aircraft that have fuel constraints, or
30 minutes when the activity involves aircraft that are not
typically fuel constrained.
After completion of the activity (e.g., prior to
maneuvering off station):
--When practical (e.g., when platforms are not constrained by
fuel restrictions or mission-essential follow-on commitments),
observe for marine mammals in the vicinity of where detonations
occurred; if any injured or dead marine mammals are observed,
follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets will assist in the
visual observation of the area where detonations occurred.
------------------------------------------------------------------------

Procedural Mitigation for Explosive Medium-Caliber and Large-Caliber
Projectiles
Procedural mitigation for Explosive Medium-Caliber and Large-
Caliber Projectiles is described in Table 40 below.

[[Page 33995]]

Table 40--Procedural Mitigation for Explosive Medium-Caliber and Large-
Caliber Projectiles
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Gunnery activities using explosive medium-caliber and large-
caliber projectiles:
--Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
1 Lookout on the vessel conducting the activity:
--For activities using explosive large-caliber projectiles,
depending on the activity, the Lookout could be the same as the
one described in Table 37 for Weapons Firing Noise.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) will support observing the mitigation zone for marine
mammals while performing their regular duties.
Mitigation Requirements:
Mitigation zones:
--600 yd around the intended impact location for explosive
medium-caliber projectiles.
--1,000 yd around the intended impact location for explosive
large-caliber projectiles.
Prior to the initial start of the activity (e.g., when
maneuvering on station):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease firing.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
firing) until one of the following conditions has been met: (1)
The animal is observed exiting the mitigation zone; (2) the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to
the intended impact location; (3) the mitigation zone has been
clear from any additional sightings for 30 minutes for vessel-
based firing; or (4) for activities using mobile targets, the
intended impact location has transited a distance equal to
double that of the mitigation zone size beyond the location of
the last sighting.
After completion of the activity (e.g., prior to
maneuvering off station):
--When practical (e.g., when platforms are not constrained by
fuel restrictions or mission-essential follow-on commitments),
observe for marine mammals in the vicinity of where detonations
occurred; if any injured or dead marine mammals are observed,
follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets will assist in the
visual observation of the area where detonations occurred.
------------------------------------------------------------------------

Procedural Mitigation for Explosive Missiles
Procedural mitigation for explosive missiles is described in Table
41 below.

Table 41--Procedural Mitigation for Explosive Missiles
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Aircraft-deployed explosive missiles:
--Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
1 Lookout positioned in an aircraft.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) will support observing the mitigation zone for marine
mammals while performing their regular duties.
Mitigation Requirements:
Mitigation zone:
--2,000 yd around the intended impact location.
Prior to the initial start of the activity (e.g., during a
fly-over of the mitigation zone):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease firing.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
firing) until one of the following conditions has been met: (1)
The animal is observed exiting the mitigation zone; (2) the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to
the intended impact location; or (3) the mitigation zone has
been clear from any additional sightings for 10 minutes when
the activity involves aircraft that have fuel constraints, or
30 minutes when the activity involves aircraft that are not
typically fuel constrained.
After completion of the activity (e.g., prior to
maneuvering off station):
--When practical (e.g., when platforms are not constrained by
fuel restrictions or mission-essential follow-on commitments),
observe for marine mammals in the vicinity of where detonations
occurred; if any injured or dead marine mammals are observed,
follow established incident reporting procedures.

[[Page 33996]]

--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets will assist in the
visual observation of the area where detonations occurred.
------------------------------------------------------------------------

Procedural Mitigation for Explosive Bombs
Procedural mitigation for explosive bombs is described in Table 42
below.

Table 42--Procedural Mitigation for Explosive Bombs
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive bombs.
Number of Lookouts and Observation Platform:
1 Lookout positioned in the aircraft conducting the
activity.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) will support observing the mitigation zone for marine
mammals while performing their regular duties.
Mitigation Requirements:
Mitigation zone:
--2,500 yd around the intended target.
Prior to the initial start of the activity (e.g., when
arriving on station):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of bomb deployment.
During the activity (e.g., during target approach):
--Observe the mitigation zone for marine mammals; if observed,
cease bomb deployment.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
bomb deployment) until one of the following conditions has been
met: (1) The animal is observed exiting the mitigation zone;
(2) the animal is thought to have exited the mitigation zone
based on a determination of its course, speed, and movement
relative to the intended target; (3) the mitigation zone has
been clear from any additional sightings for 10 minutes; or (4)
for activities using mobile targets, the intended target has
transited a distance equal to double that of the mitigation
zone size beyond the location of the last sighting.
After completion of the activity (e.g., prior to
maneuvering off station):
--When practical (e.g., when platforms are not constrained by
fuel restrictions or mission-essential follow-on commitments),
observe for marine mammals in the vicinity of where detonations
occurred; if any injured or dead marine mammals are observed,
follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets will assist in the
visual observation of the area where detonations occurred.
------------------------------------------------------------------------

Procedural Mitigation for Explosive Mine Countermeasure and
Neutralization Activities
Procedural mitigation for explosive mine countermeasure and
neutralization activities is described in Table 43 below.

Table 43--Procedural Mitigation for Explosive Mine Countermeasure and
Neutralization Activities
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive mine countermeasure and neutralization
activities.
Number of Lookouts and Observation Platform:
1 Lookout positioned on a vessel or in an aircraft when
implementing the smaller mitigation zone.
2 Lookouts (one positioned in an aircraft and one on a
small boat) when implementing the larger mitigation zone.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) will support observing the mitigation zone for marine
mammals while performing their regular duties.
Mitigation Requirements:
Mitigation zones:
--600 yd around the detonation site for activities using <=5 lb
net explosive weight.
--2,100 yd around the detonation site for activities using >5-60
lb net explosive weight.
Prior to the initial start of the activity (e.g., when
maneuvering on station; typically, 10 minutes when the activity
involves aircraft that have fuel constraints, or 30 minutes when
the activity involves aircraft that are not typically fuel
constrained):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of detonations.
During the activity:

[[Page 33997]]

--Observe for marine mammals; if observed, cease detonations.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
detonations) until one of the following conditions has been
met: (1) The animal is observed exiting the mitigation zone;
(2) the animal is thought to have exited the mitigation zone
based on a determination of its course, speed, and movement
relative to detonation site; or (3) the mitigation zone has
been clear from any additional sightings for 10 minutes when
the activity involves aircraft that have fuel constraints, or
30 minutes when the activity involves aircraft that are not
typically fuel constrained.
After completion of the activity (typically 10 minutes when
the activity involves aircraft that have fuel constraints, or 30
minutes when the activity involves aircraft that are not typically
fuel constrained):
--Observe for marine mammals in the vicinity of where
detonations occurred; if any injured or dead marine mammals are
observed, follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets will assist in the
visual observation of the area where detonations occurred.
------------------------------------------------------------------------

Procedural Mitigation for Explosive Mine Neutralization Activities
lnvolving Navy Divers
Procedural mitigation for explosive mine neutralization activities
involving Navy divers is described in Table 44 below.

Table 44--Procedural Mitigation for Explosive Mine Neutralization
Activities Involving Navy Divers
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive mine neutralization activities involving Navy
divers.
Number of Lookouts and Observation Platform:
2 Lookouts on two small boats with one Lookout each, one of
which will be a Navy biologist.
All divers placing the charges on mines will support the
Lookouts while performing their regular duties and will report
applicable sightings to the lead Lookout, the supporting small
boat, or the Range Safety Officer.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) will support observing the mitigation zone for marine
mammals while performing their regular duties.
Mitigation Requirements:
Mitigation zone:
--500 yd around the detonation site during activities using >0.5-
2.5 lb net explosive weight.
Prior to the initial start of the activity (starting 30
minutes before the first planned detonation):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of detonations.
--The Navy will ensure the area is clear of marine mammals for
30 minutes prior to commencing a detonation.
--A Navy biologist will serve as the lead Lookout and will make
the final determination that the mitigation zone is clear of
any biological resource sightings prior to the commencement of
a detonation. The Navy biologist will maintain radio
communication with the unit conducting the event and the other
Lookout.
During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease detonations.
--To the maximum extent practicable depending on mission
requirements, safety, and environmental conditions, boats will
position themselves near the midpoint of the mitigation zone
radius (but outside of the detonation plume and human safety
zone), will position themselves on opposite sides of the
detonation location, and will travel in a circular pattern
around the detonation location with one Lookout observing
inward toward the detonation site and the other observing
outward toward the perimeter of the mitigation zone.
--The Navy will use only positively controlled charges (i.e., no
time-delay fuses).
--The Navy will use the smallest practicable charge size for
each activity.
--Activities will be conducted in Beaufort sea state number 2
conditions or better and will not be conducted in low
visibility conditions.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
detonations) until one of the following conditions has been
met: (1) The animal is observed exiting the mitigation zone;
(2) the animal is thought to have exited the mitigation zone
based on a determination of its course, speed, and movement
relative to the detonation site; or (3) the mitigation zone has
been clear from any additional sightings for 30 minutes.
After each detonation and the completion of an activity
(for 30 minutes):
--Observe for marine mammals in the vicinity of where
detonations occurred and immediately downstream of the
detonation location; if any injured or dead marine mammals are
observed, follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets will assist in the
visual observation of the area where detonations occurred.
Additional requirements:
--At the Hood Canal Explosive Ordnance Disposal Range and
Crescent Harbor Explosive Ordnance Disposal Range, naval units
will obtain permission from the appropriate designated Command
authority prior to conducting explosive mine neutralization
activities involving the use of Navy divers.

[[Page 33998]]

--At the Hood Canal Explosive Ordnance Disposal Range, during
February, March, and April (the juvenile migration period for
Hood Canal Summer Run Chum), the Navy will not use explosives
in bin E3 (>0.5-2.5 lb net explosive weight), and will instead
use explosives in bin E0 (<0.1 lb net explosive weight).
--At the Hood Canal Explosive Ordnance Disposal Range, during
August, September, and October (the adult migration period for
Hood Canal summer-run chum and Puget Sound Chinook), the Navy
will avoid the use of explosives in bin E3 (>0.5-2.5 lb net
explosive weight), and will instead use explosive bin E0 (<0.1
lb net explosive weight) to the maximum extent practicable
unless necessitated by mission requirements.
--At the Crescent Harbor Explosive Ordnance Disposal Range, the
Navy will conduct explosive activities at least 1,000 m from
the closest point of land to avoid or reduce impacts on fish
(e.g., bull trout) in nearshore habitat areas.
------------------------------------------------------------------------

Procedural Mitigation for Physical Disturbance and Strike Stressors
Mitigation measures for physical disturbance and strike stressors
are provided in Tables 45 through 49.
Procedural Mitigation for Vessel Movement
Procedural mitigation for vessel movement is described in Table 45
below.

Table 45--Procedural Mitigation for Vessel Movement
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Vessel movement:
--The mitigation will not be applied if: (1) The vessel's safety
is threatened, (2) the vessel is restricted in its ability to
maneuver (e.g., during launching and recovery of aircraft or
landing craft, during towing activities, when mooring, during
Transit Protection Program exercises or other events involving
escort vessels), (3) the vessel is operated autonomously, or
(4) when impractical based on mission requirements (e.g.,
during test body retrieval by range craft).
Number of Lookouts and Observation Platform:
1 Lookout on the vessel that is underway.
Mitigation Requirements:
Mitigation zones:
--500 yd (for surface ships other than small boats) around
whales.
--200 yd (for surface ships other than small boats) around all
marine mammals other than whales (except bow-riding dolphins
and pinnipeds hauled out on man-made navigational structures,
port structures, and vessels).
--100 yd (for small boats, such as range craft) around marine
mammals (except bow-riding dolphins and pinnipeds hauled out on
man-made navigational structures, port structures, and
vessels).
During the activity:
--When underway, observe the mitigation zone for marine mammals;
if observed, maneuver to maintain distance.
Additional requirements:
--Prior to Small Boat Attack exercises at Naval Station Everett,
Naval Base Kitsap Bangor, or Naval Base Kitsap Bremerton, Navy
event planners will coordinate with Navy biologists during the
event planning process. Navy biologists will work with NMFS to
determine the likelihood of marine mammal presence in the
planned training location. Navy biologists will notify event
planners of the likelihood of species presence as they plan
specific details of the event (e.g., timing, location,
duration). The Navy will provide additional environmental
awareness training to event participants. The training will
alert participating ship and aircraft crews to the possible
presence of marine mammals in the training location. Lookouts
will use the information to assist their visual observation of
applicable mitigation zones and to aid in the implementation of
procedural mitigation.
--If a marine mammal vessel strike occurs, the Navy will follow
the established incident reporting procedures.
------------------------------------------------------------------------

Procedural Mitigation for Towed In-Water Devices

Table 46--Procedural Mitigation for Towed In-Water Devices
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Towed in-water devices:
--Mitigation applies to devices towed from a manned surface
platform or manned aircraft, or when a manned support craft is
already participating in an activity involving in-water devices
being towed by unmanned platforms.
--The mitigation will not be applied if the safety of the towing
platform or in-water device is threatened.
Number of Lookouts and Observation Platform:
1 Lookout positioned on the towing platform or support
craft.
Mitigation Requirements:
Mitigation zones:
--250 yd (for in-water devices towed by aircraft or surface
ships other than small boats) around marine mammals (except bow-
riding dolphins and pinnipeds hauled out on man-made
navigational structures, port structures, and vessels).

[[Page 33999]]

--100 yd (for in-water devices towed by small boats, such as
range craft) around marine mammals (except bow-riding dolphins
and pinnipeds hauled out on man-made navigational structures,
port structures, and vessels).
During the activity (i.e., when towing an in-water device):
--Observe the mitigation zone for marine mammals; if observed,
maneuver to maintain distance.
------------------------------------------------------------------------

Procedural Mitigation for Small-, Medium-, and Large-Caliber Non-
Explosive Practice Munitions

Table 47--Procedural Mitigation for Small-, Medium-, and Large-Caliber
Non-Explosive Practice Munitions
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Gunnery activities using small-, medium-, and large-caliber
non-explosive practice munitions:
--Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
1 Lookout positioned on the platform conducting the
activity.
Depending on the activity, the Lookout could be the same as
the one described in Table 37 for Weapons Firing Noise.
Mitigation Requirements:
Mitigation zone:
--200 yd around the intended impact location.
Prior to the initial start of the activity (e.g., when
maneuvering on station):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease firing.
Commencement/recommencement conditions after a marine
mammal sighting before or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
firing) until one of the following conditions has been met: (1)
The animal is observed exiting the mitigation zone; (2) the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to
the intended impact location; (3) the mitigation zone has been
clear from any additional sightings for 10 minutes for aircraft-
based firing or 30 minutes for vessel-based firing; or (4) for
activities using a mobile target, the intended impact location
has transited a distance equal to double that of the mitigation
zone size beyond the location of the last sighting.
------------------------------------------------------------------------

Procedural Mitigation for Non-Explosive Missiles

Table 48--Procedural Mitigation for Non-Explosive Missiles
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Aircraft-deployed non-explosive missiles:
--Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
1 Lookout positioned in an aircraft.
Mitigation Requirements:
Mitigation zone:
--900 yd around the intended impact location.
Prior to the initial start of the activity (e.g., during a
fly-over of the mitigation zone):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if observed,
cease firing.
Commencement/recommencement conditions after a marine
mammal sighting prior to or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
firing) until one of the following conditions has been met: (1)
The animal is observed exiting the mitigation zone; (2) the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to
the intended impact location; or (3) the mitigation zone has
been clear from any additional sightings for 10 minutes when
the activity involves aircraft that have fuel constraints, or
30 minutes when the activity involves aircraft that are not
typically fuel constrained.
------------------------------------------------------------------------

[[Page 34000]]

Procedural Mitigation for Non-Explosive Bombs and Mine Shapes

Table 49--Procedural Mitigation for Non-Explosive Bombs and Mine Shapes
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Non-explosive bombs.
Non-explosive mine shapes during mine laying activities.
Number of Lookouts and Observation Platform:
1 Lookout positioned in an aircraft.
Mitigation Requirements:
Mitigation zone:
--1,000 yd around the intended target.
Prior to the initial start of the activity (e.g., when
arriving on station):
--Observe the mitigation zone for floating vegetation; if
observed, relocate or delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if observed,
relocate or delay the start of bomb deployment or mine laying.
During the activity (e.g., during approach of the target or
intended minefield location):
--Observe the mitigation zone for marine mammals; if observed,
cease bomb deployment or mine laying.
Commencement/recommencement conditions after a marine
mammal sighting prior to or during the activity:
--The Navy will allow a sighted marine mammal to leave the
mitigation zone prior to the initial start of the activity (by
delaying the start) or during the activity (by not recommencing
bomb deployment or mine laying) until one of the following
conditions has been met: (1) The animal is observed exiting the
mitigation zone; (2) the animal is thought to have exited the
mitigation zone based on a determination of its course, speed,
and movement relative to the intended target or minefield
location; (3) the mitigation zone has been clear from any
additional sightings for 10 minutes; or (4) for activities
using mobile targets, the intended target has transited a
distance equal to double that of the mitigation zone size
beyond the location of the last sighting.
------------------------------------------------------------------------

Mitigation Areas

In addition to procedural mitigation, the Navy would implement
mitigation measures within mitigation areas to avoid or minimize
potential impacts on marine mammals. A full technical analysis (for
which the methods were summarized above) of the mitigation areas that
the Navy considered for marine mammals is provided in Appendix K
(Geographic Mitigation Assessment) of the 2019 NWTT DSEIS/OEIS. The
Navy took into account public comments received on the 2019 NWTT DSEIS/
OEIS, the best available science, and the practicability of
implementing additional mitigation measures and has enhanced its
mitigation areas and mitigation measures beyond those that were
included in the 2015-2020 regulations to further reduce impacts to
marine mammals.
Information on the mitigation measures that the Navy will implement
within mitigation areas is provided in Table 50 (see below). The
mitigation applies year-round unless specified otherwise in the table.
NMFS conducted an independent analysis of the mitigation areas that
the Navy proposed, which are described below. NMFS preliminarily
concurs with the Navy's analysis, which indicates that the measures in
these mitigation areas are both practicable and will reduce the
likelihood or severity of adverse impacts to marine mammal species or
their habitat in the manner described in the Navy's analysis and this
rule. NMFS is heavily reliant on the Navy's description of operational
practicability, since the Navy is best equipped to describe the degree
to which a given mitigation measure affects personnel safety or mission
effectiveness, and is practical to implement. The Navy considers the
measures in this proposed rule to be practicable, and NMFS concurs. We
further discuss the manner in which the Geographic Mitigation Areas in
the proposed rule will reduce the likelihood or severity of adverse
impacts to marine mammal species or their habitat in the Preliminary
Analysis and Negligible Impact Determination section.

Table 50--Geographic Mitigation Areas for Marine Mammals in the NWTT
Study Area
------------------------------------------------------------------------
Mitigation area description
-------------------------------------------------------------------------
Stressor or Activity:
Sonar.
Explosives.
Physical disturbance and strikes.
Mitigation Requirements:
Marine Species Coastal Mitigation Area (year-round):
--Within 50 nmi from shore in the Marine Species Coastal
Mitigation Area, the Navy will not conduct: (1) Explosive
training activities, (2) explosive testing activities (with the
exception of explosive Mine Countermeasure and Neutralization
Testing activities), and (3) non-explosive missile training
activities. Should national security present a requirement to
conduct these activities in the mitigation area, naval units
will obtain permission from the appropriate designated Command
authority prior to commencement of the activity. The Navy will
provide NMFS with advance notification and include information
about the event in its annual activity reports to NMFS.
--Within 20 nmi from shore in the Marine Species Coastal
Mitigation Area, the Navy will not conduct non-explosive large-
caliber gunnery training activities and non-explosive bombing
training activities. Should national security present a
requirement to conduct these activities in the mitigation area,
naval units will obtain permission from the appropriate
designated Command authority prior to commencement of the
activity. The Navy will provide NMFS with advance notification
and include information about the event in its annual activity
reports to NMFS.

[[Page 34001]]

--Within 12 nmi from shore in the Marine Species Coastal
Mitigation Area, the Navy will not conduct: (1) Non-explosive
small- and medium-caliber gunnery training activities, (2) non-
explosive torpedo training activities, and (3) Anti-Submarine
Warfare Tracking Exercise--Helicopter, Maritime Patrol
Aircraft, Ship, or Submarine training activities. Should
national security present a requirement to conduct these
activities in the mitigation area, naval units will obtain
permission from the appropriate designated Command authority
prior to commencement of the activity. The Navy will provide
NMFS with advance notification and include information about
the event in its annual activity reports to NMFS.
Olympic Coast National Marine Sanctuary Mitigation Area
(year-round):
--Within the Olympic Coast National Marine Sanctuary Mitigation
Area, the Navy will not conduct more than 32 hours of MF1 mid-
frequency active sonar during training annually and will not
conduct non-explosive bombing training activities. Should
national security present a requirement to conduct more than 32
hours of MF1 mid-frequency active sonar during training
annually or conduct non-explosive bombing training activities
in the mitigation area, naval units will obtain permission from
the appropriate designated Command authority prior to
commencement of the activity. The Navy will provide NMFS with
advance notification and include information about the event in
its annual activity reports to NMFS.
--Within the Olympic Coast National Marine Sanctuary Mitigation
Area, the Navy will not conduct more than 33 hours of MF1 mid-
frequency active sonar during testing annually (except within
the portion of the mitigation area that overlaps the Quinault
Range Site) and will not conduct explosive Mine Countermeasure
and Neutralization Testing activities. Should national security
present a requirement for the Navy to conduct more than 33
hours of MF1 mid-frequency active sonar during testing annually
(except within the portion of the mitigation area that overlaps
the Quinault Range Site) or conduct explosive Mine
Countermeasure and Neutralization Testing activities in the
mitigation area, naval units will obtain permission from the
appropriate designated Command authority prior to commencement
of the activity. The Navy will provide NMFS with advance
notification and include information about the event in its
annual activity reports to NMFS.
Stonewall and Heceta Bank Humpback Whale Mitigation Area
(May 1-November 30):
--Within the Stonewall and Heceta Bank Humpback Whale Mitigation
Area, the Navy will not use MF1 mid-frequency active sonar or
explosives during training and testing from May 1 to November
30. Should national security present a requirement to use MF1
mid-frequency active sonar or explosives during training and
testing from May 1 to November 30, naval units will obtain
permission from the appropriate designated Command authority
prior to commencement of the activity. The Navy will provide
NMFS with advance notification and include information about
the event in its annual activity reports to NMFS.
Point St. George Humpback Whale Mitigation Area (July 1-
November 30):
--Within the Point St. George Humpback Whale Mitigation Area,
the Navy will not use MF1 mid-frequency active sonar or
explosives during training and testing from July 1 to November
30. Should national security present a requirement to use MF1
mid-frequency active sonar or explosives during training and
testing from July 1 to November 30, naval units will obtain
permission from the appropriate designated Command authority
prior to commencement of the activity. The Navy will provide
NMFS with advance notification and include information about
the event in its annual activity reports to NMFS.
Puget Sound and Strait of Juan de Fuca Mitigation Area
(year-round):
--Within the Puget Sound and Strait of Juan de Fuca Mitigation
Area, the Navy will require units to obtain approval from the
appropriate designated Command authority prior to: (1) The use
of hull-mounted mid-frequency active sonar during training
while underway, and (2) conducting ship and submarine active
sonar pierside maintenance or testing.
--Within the Puget Sound and Strait of Juan de Fuca Mitigation
Area for Civilian Port Defense--Homeland Security Anti-
Terrorism/Force Protection Exercises, Navy event planners will
coordinate with Navy biologists during the event planning
process. Navy biologists will work with NMFS to determine the
likelihood of gray whale and Southern Resident Killer Whale
presence in the planned training location. Navy biologists will
notify event planners of the likelihood of species presence as
they plan specific details of the event (e.g., timing,
location, duration). The Navy will ensure environmental
awareness of event participants. Environmental awareness will
help alert participating ship and aircraft crews to the
possible presence of marine mammals in the training location,
such as gray whales and Southern Resident Killer Whales.
Northern Puget Sound Gray Whale Mitigation Area (March 1-
May 31):
--Within the Northern Puget Sound Gray Whale Mitigation Area,
the Navy will not conduct Civilian Port Defense--Homeland
Security Anti-Terrorism/Force Protection Exercises from March 1
to May 31. Should national security present a requirement to
conduct Civilian Port Defense--Homeland Security Anti-Terrorism/
Force Protection Exercises from March 1 to May 31, naval units
will obtain permission from the appropriate designated Command
authority prior to commencement of the activity. The Navy will
provide NMFS with advance notification and include information
about the event in its annual activity reports to NMFS.
------------------------------------------------------------------------

BILLING CODE 3510-22-P

[[Page 34002]]

[GRAPHIC] [TIFF OMITTED] TP02JN20.007

BILLING CODE 3510-22-C

[[Page 34003]]

Mitigation Conclusions

NMFS has carefully evaluated the Navy's proposed mitigation
measures--many of which were developed with NMFS' input during the
previous phases of Navy training and testing authorizations but several
of which are new since implementation of the current 2015 to 2020
regulations--and considered a broad range of other measures (i.e., the
measures considered but eliminated in the 2019 NWTT DSEIS/OEIS, which
reflect many of the comments that have arisen via NMFS or public input
in past years) in the context of ensuring that NMFS prescribes the
means of effecting the least practicable adverse impact on the affected
marine mammal species and their habitat. Our evaluation of potential
measures included consideration of the following factors in relation to
one another: The manner in which, and the degree to which, the
successful implementation of the mitigation measures is expected to
reduce the likelihood and/or magnitude of adverse impacts to marine
mammal species and their habitat; the proven or likely efficacy of the
measures; and the practicability of the measures for applicant
implementation, including consideration of personnel safety,
practicality of implementation, and impact on the effectiveness of the
military readiness activity.
Based on our evaluation of the Navy's proposed measures, as well as
other measures considered by the Navy and NMFS, NMFS has preliminarily
determined that these proposed mitigation measures are appropriate
means of effecting the least practicable adverse impact on marine
mammal species and their habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and
considering specifically personnel safety, practicality of
implementation, and impact on the effectiveness of the military
readiness activity. Additionally, an adaptive management component
helps further ensure that mitigation is regularly assessed and provides
a mechanism to improve the mitigation, based on the factors above,
through modification as appropriate.
The proposed rule comment period provides the public an opportunity
to submit recommendations, views, and/or concerns regarding the Navy's
activities and the proposed mitigation measures. While NMFS has
preliminarily determined that the Navy's proposed mitigation measures
would effect the least practicable adverse impact on the affected
species and their habitat, NMFS will consider all public comments to
help inform our final determination. Consequently, the proposed
mitigation measures may be refined, modified, removed, or added to
prior to the issuance of the final rule based on public comments
received and, as appropriate, analysis of additional potential
mitigation measures.

Proposed Monitoring

Section 101(a)(5)(A) of the MMPA states that in order to authorize
incidental take for an activity, NMFS must set forth requirements
pertaining to the monitoring and reporting of such taking. The MMPA
implementing regulations at 50 CFR 216.104(a)(13) indicate that
requests for incidental take authorizations must include the suggested
means of accomplishing the necessary monitoring and reporting that will
result in increased knowledge of the species and of the level of taking
or impacts on populations of marine mammals that are expected to be
present.
Although the Navy has been conducting research and monitoring in
the NWTT Study Area for over 20 years, it developed a formal marine
species monitoring program in support of the MMPA and ESA
authorizations in 2009. This robust program has resulted in hundreds of
technical reports and publications on marine mammals that have informed
Navy and NMFS analyses in environmental planning documents, rules, and
Biological Opinions. The reports are made available to the public on
the Navy's marine species monitoring website
(www.navymarinespeciesmonitoring.us) and the data on the Ocean
Biogeographic Information System Spatial Ecological Analysis of
Megavertebrate Populations (OBIS-SEAMAP) (https://seamap.env.duke.edu/).
The Navy will continue collecting monitoring data to inform our
understanding of the occurrence of marine mammals in the NWTT Study
Area; the likely exposure of marine mammals to stressors of concern in
the NWTT Study Area; the response of marine mammals to exposures to
stressors; the consequences of a particular marine mammal response to
their individual fitness and, ultimately, populations; and the
effectiveness of implemented mitigation measures. Taken together,
mitigation and monitoring comprise the Navy's integrated approach for
reducing environmental impacts from the specified activities. The
Navy's overall monitoring approach seeks to leverage and build on
existing research efforts whenever possible.
As agreed upon between the Navy and NMFS, the monitoring measures
presented here, as well as the mitigation measures described above,
focus on the protection and management of potentially affected marine
mammals. A well-designed monitoring program can provide important
feedback for validating assumptions made in analyses and allow for
adaptive management of marine resources. Monitoring is required under
the MMPA, and details of the monitoring program for the specified
activities have been developed through coordination between NMFS and
the Navy through the regulatory process for previous Navy at-sea
training and testing activities.

Integrated Comprehensive Monitoring Program

The Navy's Integrated Comprehensive Monitoring Program (ICMP) is
intended to coordinate marine species monitoring efforts across all
regions and to allocate the most appropriate level and type of effort
for each range complex based on a set of standardized objectives, and
in acknowledgement of regional expertise and resource availability. The
ICMP is designed to be flexible, scalable, and adaptable through the
adaptive management and strategic planning processes to periodically
assess progress and reevaluate objectives. This process includes
conducting an annual adaptive management review meeting, at which the
Navy and NMFS jointly consider the prior-year goals, monitoring
results, and related scientific advances to determine if monitoring
plan modifications are warranted to more effectively address program
goals. Although the ICMP does not specify actual monitoring field work
or individual projects, it does establish a matrix of goals and
objectives that have been developed in coordination with NMFS. As the
ICMP is implemented through the Strategic Planning Process, detailed
and specific studies will be developed which support the Navy's and
NMFS top-level monitoring goals. In essence, the ICMP directs that
monitoring activities relating to the effects of Navy training and
testing activities on marine species should be designed to contribute
towards or accomplish one or more of the following top-level goals:
An increase in the understanding of the likely occurrence
of marine mammals and ESA-listed marine species in the vicinity of the
action (i.e., presence, abundance, distribution, and density of
species);
An increase in the understanding of the nature, scope, or
context of the

[[Page 34004]]

likely exposure of marine mammals and ESA-listed species to any of the
potential stressors associated with the action (e.g., sound, explosive
detonation, or expended materials), through better understanding of one
or more of the following: (1) The nature of the action and its
surrounding environment (e.g., sound-source characterization,
propagation, and ambient noise levels), (2) the affected species (e.g.,
life history or dive patterns), (3) the likely co-occurrence of marine
mammals and ESA-listed marine species with the action (in whole or
part), and (4) the likely biological or behavioral context of exposure
to the stressor for the marine mammal and ESA-listed marine species
(e.g., age class of exposed animals or known pupping, calving, or
feeding areas);
An increase in the understanding of how individual marine
mammals or ESA-listed marine species respond (behaviorally or
physiologically) to the specific stressors associated with the action
(in specific contexts, where possible, e.g., at what distance or
received level);
An increase in the understanding of how anticipated
individual responses, to individual stressors or anticipated
combinations of stressors, may impact either (1) the long-term fitness
and survival of an individual; or (2) the population, species, or stock
(e.g., through impacts on annual rates of recruitment or survival);
An increase in the understanding of the effectiveness of
mitigation and monitoring measures;
A better understanding and record of the manner in which
the Navy complies with the incidental take regulations and LOAs and the
ESA Incidental Take Statement;
An increase in the probability of detecting marine mammals
(through improved technology or methods), both specifically within the
mitigation zone (thus allowing for more effective implementation of the
mitigation) and in general, to better achieve the above goals; and
Ensuring that adverse impact of activities remains at the
least practicable level.

Strategic Planning Process for Marine Species Monitoring

The Navy also developed the Strategic Planning Process for Marine
Species Monitoring, which serves to guide the investment of resources
to most efficiently address ICMP objectives and intermediate scientific
objectives developed through this process. The Strategic Planning
Process establishes the guidelines and processes necessary to develop,
evaluate, and fund individual projects based on objective scientific
study questions. The process uses an underlying framework designed
around intermediate scientific objectives and a conceptual framework
incorporating a progression of knowledge spanning occurrence, exposure,
response, and consequence. The Strategic Planning Process for Marine
Species Monitoring is used to set overarching intermediate scientific
objectives; develop individual monitoring project concepts; evaluate,
prioritize, and select specific monitoring projects to fund or continue
supporting for a given fiscal year; execute and manage selected
monitoring projects; and report and evaluate progress and results. This
process addresses relative investments to different range complexes
based on goals across all range complexes, and monitoring would
leverage multiple techniques for data acquisition and analysis whenever
possible. More information on the Strategic Planning Process for Marine
Species Monitoring including results, reports, and publications, is
also available online (https://www.navymarinespeciesmonitoring.us/).

Past and Current Monitoring in the NWTT Study Area

The monitoring program has undergone significant changes since the
first rule was issued for the NWTT Study Area in 2010, which highlights
the monitoring program's evolution through the process of adaptive
management. The monitoring program developed for the first cycle of
environmental compliance documents (e.g., U.S. Department of the Navy,
2008a, 2008b) utilized effort-based compliance metrics that were
somewhat limiting. Through adaptive management discussions, the Navy
designed and conducted monitoring studies according to scientific
objectives and eliminated specific effort requirements.
Progress has also been made on the conceptual framework categories
from the Scientific Advisory Group for Navy Marine Species Monitoring
(U.S. Department of the Navy, 2011), ranging from occurrence of
animals, to their exposure, response, and population consequences. The
Navy continues to manage the Atlantic and Pacific program as a whole,
with monitoring in each range complex taking a slightly different but
complementary approach. The Navy has continued to use the approach of
layering multiple simultaneous components in many of the range
complexes to leverage an increase in return of the progress toward
answering scientific monitoring questions. This includes in the NWTT
Study Area, for example, (a) satellite tagging of blue whales, fin
whales, humpback whales, and Southern Resident killer whales; (b)
analysis of existing passive acoustic monitoring datasets; and (c)
line-transect aerial surveys for marine mammals in Puget Sound,
Washington.
Numerous publications, dissertations, and conference presentations
have resulted from research conducted under the marine species
monitoring program (https://www.navymarinespeciesmonitoring.us/reading-room/publications/), leading to a significant contribution to the body
of marine mammal science. Publications on occurrence, distribution, and
density have fed the modeling input, and publications on exposure and
response have informed Navy and NMFS analysis of behavioral response
and consideration of mitigation measures.
Furthermore, collaboration between the monitoring program and the
Navy's research and development (e.g., the Office of Naval Research)
and demonstration-validation (e.g., Living Marine Resources) programs
has been strengthened, leading to research tools and products that have
already transitioned to the monitoring program. These include Marine
Mammal Monitoring on Ranges, controlled exposure experiment behavioral
response studies, acoustic sea glider surveys, and global positioning
system-enabled satellite tags. Recent progress has been made with
better integration with monitoring across all Navy at-sea study areas,
including the Atlantic Fleet Training and Testing Study Area in the
Atlantic Ocean, and various other ranges. Publications from the Living
Marine Resources and Office of Naval Research programs have also
resulted in significant contributions to hearing, acoustic criteria
used in effects modeling, exposure, and response, as well as in
developing tools to assess biological significance (e.g.,
consequences).
NMFS and the Navy also consider data collected during procedural
mitigations as monitoring. Data are collected by shipboard personnel on
hours spent training, hours of observation, hours of sonar, and marine
mammals observed within the mitigation zones when mitigations are
implemented. These data are provided to NMFS in both classified and
unclassified annual exercise reports, which would continue under this
proposed rule.
NMFS has received multiple years' worth of annual exercise and
monitoring reports addressing active

[[Page 34005]]

sonar use and explosive detonations within the NWTT Study Area and
other Navy range complexes. The data and information contained in these
reports have been considered in developing mitigation and monitoring
measures for the proposed training and testing activities within the
NWTT Study Area. The Navy's annual exercise and monitoring reports may
be viewed at: https://www.fisheries.noaa.gov/national/marine-mammal-
protection/incidental-take-authorizations-military-readiness-activities
and https://www.navymarinespeciesmonitoring.us/reporting/.
The Navy's marine species monitoring program typically supports
several monitoring projects in the NWTT Study Area at any given time.
Additional details on the scientific objectives for each project can be
found at https://www.navymarinespeciesmonitoring.us/regions/pacific/current-projects/. Projects can be either major multi-year efforts, or
one to two-year special studies. The emphasis on monitoring in the
Pacific Northwest is directed towards collecting and analyzing tagging
data related to the occurrence of blue whales, fin whales, humpback
whales, and Southern Resident killer whales. In 2017, researchers
deployed 28 tags on blue whales and one tag on a fin whale off southern
and central California (Mate et al., 2017). Detailed analyses for the
2017 tagging effort are ongoing and will be available later in a final
report and posted at https://www.navymarinespeciesmonitoring.us/.
Humpback whales have been tagged with satellite tags, and biopsy
samples have been collected (Mate et al., 2017). Location information
on Southern Resident killer whales was provided via satellite tag data
and acoustic detections (Hanson et al., 2018). Also, distribution of
Chinook salmon (a key prey species of Southern Resident killer whales)
in coastal waters from Alaska to Northern California was studied
(Shelton et al., in review). Future monitoring efforts in the NWTT
Study Area are anticipated to continue along the same objectives:
Determining the species and populations of marine mammals present and
potentially exposed to Navy training and testing activities in the NWTT
Study Area, through tagging, passive acoustic monitoring, refined
modeling, photo identification, biopsies, and visual monitoring.

Adaptive Management

The proposed regulations governing the take of marine mammals
incidental to Navy training and testing activities in the NWTT Study
Area contain an adaptive management component. Our understanding of the
effects of Navy training and testing activities (e.g., acoustic and
explosive stressors) on marine mammals continues to evolve, which makes
the inclusion of an adaptive management component both valuable and
necessary within the context of seven-year regulations.
The reporting requirements associated with this rule are designed
to provide NMFS with monitoring data from the previous year to allow
NMFS to consider whether any changes to existing mitigation and
monitoring requirements are appropriate. The use of adaptive management
allows NMFS to consider new information from different sources to
determine (with input from the Navy regarding practicability) on an
annual or biennial basis if mitigation or monitoring measures should be
modified (including additions or deletions). Mitigation measures could
be modified if new data suggests that such modifications would have a
reasonable likelihood of more effectively accomplishing the goals of
the mitigation and monitoring and if the measures are practicable. If
the modifications to the mitigation, monitoring, or reporting measures
are substantial, NMFS would publish a notice of the planned LOAs in the
Federal Register and solicit public comment.
The following are some of the possible sources of applicable data
to be considered through the adaptive management process: (1) Results
from monitoring and exercise reports, as required by MMPA
authorizations; (2) compiled results of Navy funded research and
development studies; (3) results from specific stranding
investigations; (4) results from general marine mammal and sound
research; and (5) any information which reveals that marine mammals may
have been taken in a manner, extent, or number not authorized by these
regulations or subsequent LOAs. The results from monitoring reports and
other studies may be viewed at https://www.navymarinespeciesmonitoring.us.

Proposed Reporting

In order to issue incidental take authorization for an activity,
section 101(a)(5)(A) of the MMPA states that NMFS must set forth
requirements pertaining to the monitoring and reporting of such taking.
Effective reporting is critical both to compliance as well as ensuring
that the most value is obtained from the required monitoring. Reports
from individual monitoring events, results of analyses, publications,
and periodic progress reports for specific monitoring projects will be
posted to the Navy's Marine Species Monitoring web portal: https://www.navymarinespeciesmonitoring.us.
There are several different reporting requirements pursuant to the
current regulations. All of these reporting requirements would be
continued under this proposed rule for the seven-year period.

Notification of Injured, Live Stranded or Dead Marine Mammals

The Navy would consult the Notification and Reporting Plan, which
sets out notification, reporting, and other requirements when injured,
live stranded, or dead marine mammals are detected. The Notification
and Reporting Plan is available for review at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-
take-authorizations-military-readiness-activities.

Annual NWTT Monitoring Report

The Navy would submit an annual report to NMFS of the NWTT
monitoring describing the implementation and results from the previous
calendar year. Data collection methods would be standardized across
Pacific Range Complexes including the MITT, HSTT, NWTT, and Gulf of
Alaska (GOA) Study Areas to allow for comparison in different
geographic locations. The draft of the annual monitoring report would
be submitted either three months after the end of the calendar year or
three months after the conclusion of the monitoring year, to be
determined by the Adaptive Management process. NMFS will submit
comments or questions on the report, if any, within one month of
receipt. The report will be considered final after the Navy has
addressed NMFS' comments, or one month after submittal of the draft if
NMFS does not provide comments on the draft report. Such a report would
describe progress of knowledge made with respect to intermediate
scientific objectives within the NWTT Study Area associated with the
ICMP. Similar study questions would be treated together so that
summaries can be provided for each topic area. The report need not
include analyses and content that do not provide direct assessment of
cumulative progress on the monitoring plan study questions. NMFS would
submit comments on the draft monitoring report, if any, within three
months of receipt. The report would be considered final after the Navy
has addressed NMFS' comments, or three months after the submittal of
the draft if NMFS does not have comments.
As an alternative, the Navy may submit a Pacific-Range Complex
annual

[[Page 34006]]

Monitoring Plan report to fulfill this requirement. Such a report
describes progress of knowledge made with respect to monitoring study
questions across multiple Navy ranges associated with the ICMP. Similar
study questions would be treated together so that progress on each
topic is summarized across multiple Navy ranges. The report need not
include analyses and content that does not provide direct assessment of
cumulative progress on the monitoring study question. This would
continue to allow the Navy to provide a cohesive monitoring report
covering multiple ranges (as per ICMP goals), rather than entirely
separate reports for the NWTT, GOA, MITT, and HSTT Study Areas.

Annual NWTT Training Exercise Report and Testing Activity Reports

Each year, the Navy would submit one preliminary report (Quick Look
Report) to NMFS detailing the status of applicable sound sources within
21 days after the anniversary of the date of issuance of the LOA. Each
year, the Navy would also submit a detailed report (NWTT Annual
Training Exercise Report and Testing Activity Report) to NMFS within
three months after the one-year anniversary of the date of issuance of
the LOA. NMFS will submit comments or questions on the report, if any,
within one month of receipt. The report will be considered final after
the Navy has addressed NMFS' comments, or one month after submittal of
the draft if NMFS does not provide comments on the draft report. The
annual report would contain a summary of all sound sources used (total
hours or quantity (per the LOA) of each bin of sonar or other non-
impulsive source; total annual number of each type of explosive
exercises; and total annual expended/detonated rounds (missiles, bombs,
sonobuoys, etc.) for each explosive bin). The annual report will also
contain cumulative sonar and explosive use quantity from previous
years' reports through the current year. Additionally, if there were
any changes to the sound source allowance in the reporting year, or
cumulatively, the report would include a discussion of why the change
was made and include analysis to support how the change did or did not
affect the analysis in the NWTT EIS/OEIS and MMPA final rule. The
annual report would also include the details regarding specific
requirements associated with specific mitigation areas. The analysis in
the detailed report would be based on the accumulation of data from the
current year's report and data collected from previous annual reports.
The final annual/close-out report at the conclusion of the
authorization period (year seven) would also serve as the comprehensive
close-out report and include both the final year annual use compared to
annual authorization as well as a cumulative seven-year annual use
compared to seven-year authorization. Information included in the
annual reports may be used to inform future adaptive management of
activities within the NWTT Study Area.
The Annual NWTT Training Exercise Report and Testing Activity Navy
report (classified or unclassified versions) could be consolidated with
other exercise reports from other range complexes in the Pacific Ocean
for a single Pacific Exercise Report, if desired.

Other Reporting and Coordination

The Navy would continue to report and coordinate with NMFS for the
following:
Annual marine species monitoring technical review meetings
that also include researchers and the Marine Mammal Commission
(currently, every two years a joint Pacific-Atlantic meeting is held);
and
Annual Adaptive Management meetings that also include the
Marine Mammal Commission (recently modified to occur in conjunction
with the annual monitoring technical review meeting).

Preliminary Analysis and Negligible Impact Determination

General Negligible Impact Analysis

Introduction
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. For Level A
harassment or Level B harassment (as presented in Tables 32 and 33), in
addition to considering estimates of the number of marine mammals that
might be taken NMFS considers other factors, such as the likely nature
of any responses (e.g., intensity, duration) and the context of any
responses (e.g., critical reproductive time or location, migration), as
well as effects on habitat and the likely effectiveness of the
mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS' implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, other ongoing sources of human-caused
mortality, and ambient noise levels).
In the Estimated Take of Marine Mammals section, we identified the
subset of potential effects that would be expected to rise to the level
of takes both annually and over the seven-year period covered by this
proposed rule, and then identified the maximum number of takes we
believe could occur (mortality) or are reasonably expected to occur
(harassment) based on the methods described. The impact that any given
take will have is dependent on many case-specific factors that need to
be considered in the negligible impact analysis (e.g., the context of
behavioral exposures such as duration or intensity of a disturbance,
the health of impacted animals, the status of a species that incurs
fitness-level impacts to individuals, etc.). For this proposed rule we
evaluated the likely impacts of the enumerated maximum number of
harassment takes that are proposed for authorization and reasonably
expected to occur, in the context of the specific circumstances
surrounding these predicted takes. We also include a specific
assessment of serious injury or mortality (hereafter referred to as M/
SI) takes that could occur, as well as consideration of the traits and
statuses of the affected species and stocks. Last, we collectively
evaluated this information, as well as other more taxa-specific
information and mitigation measure effectiveness, in group-specific
assessments that support our negligible impact conclusions for each
stock or species. Because all of the Navy's specified activities would
occur within the ranges of the marine mammal stocks identified in the
rule, all negligible impact analyses and determinations are at the
stock level (i.e., additional species-level determinations are not
needed).
Harassment
The Specified Activities reflect representative levels of training
and testing activities. The Description of the Specified Activity
section describes annual activities. There may be some flexibility in
the exact number of hours,

[[Page 34007]]

items, or detonations that may vary from year to year, but take totals
would not exceed the maximum annual totals and seven-year totals
indicated in Tables 32 and 33. We base our analysis and negligible
impact determination on the maximum number of takes that would be
reasonably expected to occur annually and are proposed to be
authorized, although, as stated before, the number of takes are only a
part of the analysis, which includes extensive qualitative
consideration of other contextual factors that influence the degree of
impact of the takes on the affected individuals. To avoid repetition,
we provide some general analysis immediately below that applies to all
the species listed in Tables 32 and 33, given that some of the
anticipated effects of the Navy's training and testing activities on
marine mammals are expected to be relatively similar in nature.
However, below that, we break our analysis into species (and/or
stocks), or groups of species (and the associated stocks) where
relevant similarities exist, to provide more specific information
related to the anticipated effects on individuals of a specific stock
or where there is information about the status or structure of any
species that would lead to a differing assessment of the effects on the
species or stock. Organizing our analysis by grouping species or stocks
that share common traits or that will respond similarly to effects of
the Navy's activities and then providing species- or stock-specific
information allows us to avoid duplication while assuring that we have
analyzed the effects of the specified activities on each affected
species or stock.
The Navy's harassment take request is based on its model and
quantitative assessment of mitigation, which NMFS reviewed and concurs
appropriately predicts the maximum amount of harassment that is
reasonably likely to occur. The model calculates sound energy
propagation from sonar, other active acoustic sources, and explosives
during naval activities; the sound or impulse received by animat
dosimeters representing marine mammals distributed in the area around
the modeled activity; and whether the sound or impulse energy received
by a marine mammal exceeds the thresholds for effects. Assumptions in
the Navy model intentionally err on the side of overestimation when
there are unknowns. Naval activities are modeled as though they would
occur regardless of proximity to marine mammals, meaning that no
mitigation is considered (e.g., no power down or shut down) and without
any avoidance of the activity by the animal. The final step of the
quantitative analysis of acoustic effects, which occurs after the
modeling (as described in the Estimated Take of Marine Mammals
section), is to consider the implementation of mitigation and the
possibility that marine mammals would avoid continued or repeated sound
exposures. NMFS provided input to, independently reviewed, and
concurred with the Navy on this process and the Navy's analysis, which
is described in detail in Section 6 of the Navy's rulemaking/LOA
application, was used to quantify harassment takes for this rule.
Generally speaking, the Navy and NMFS anticipate more severe
effects from takes resulting from exposure to higher received levels
(though this is in no way a strictly linear relationship for behavioral
effects throughout species, individuals, or circumstances) and less
severe effects from takes resulting from exposure to lower received
levels. However, there is also growing evidence of the importance of
distance in predicting marine mammal behavioral response to sound--
i.e., sounds of a similar level emanating from a more distant source
have been shown to be less likely to evoke a response of equal
magnitude (DeRuiter 2012). The estimated number of Level A harassment
and Level B harassment takes does not equate to the number of
individual animals the Navy expects to harass (which is lower), but
rather to the instances of take (i.e., exposures above the Level A
harassment and Level B harassment threshold) that are anticipated to
occur over the seven-year period. These instances may represent either
brief exposures (seconds or minutes) or, in some cases, longer
durations of exposure within a day. Some individuals may experience
multiple instances of take (meaning over multiple days) over the course
of the year, which means that the number of individuals taken is
smaller than the total estimated takes. Generally speaking, the higher
the number of takes as compared to the population abundance, the more
repeated takes of individuals are likely, and the higher the actual
percentage of individuals in the population that are likely taken at
least once in a year. We look at this comparative metric to give us a
relative sense of where a larger portion of a species is being taken by
Navy activities, where there is a higher likelihood that the same
individuals are being taken across multiple days, and where that number
of days might be higher or more likely sequential. Where the number of
instances of take is less than 100 percent of the abundance and there
is no information to specifically suggest that a small subset of
animals is being repeatedly taken over a high number of sequential
days, the overall magnitude is generally considered low, as it could on
one extreme mean that every take represents a separate individual in
the population being taken on one day (a very minimal impact) or, more
likely, that some smaller number of individuals are taken on one day
annually and some are taken on a few not likely sequential days
annually, and of course some are not taken at all.
In the ocean, the use of sonar and other active acoustic sources is
often transient and is unlikely to repeatedly expose the same
individual animals within a short period, for example within one
specific exercise. However, for some individuals of some species
repeated exposures across different activities could occur over the
year, especially where events occur in generally the same area with
more resident species. In short, for some species we expect that the
total anticipated takes represent exposures of a smaller number of
individuals of which some would be exposed multiple times, but based on
the nature of the Navy activities and the movement patterns of marine
mammals, it is unlikely that individuals from most stocks would be
taken over more than a few sequential days. This means that even where
repeated takes of individuals are likely to occur, they are more likely
to result from non-sequential exposures from different activities, and,
even if sequential, individual animals are not predicted to be taken
for more than several days in a row, at most. As described elsewhere,
the nature of the majority of the exposures would be expected to be of
a less severe nature and based on the numbers it is likely that any
individual exposed multiple times is still only taken on a small
percentage of the days of the year. The greater likelihood is that not
every individual is taken, or perhaps a smaller subset is taken with a
slightly higher average and larger variability of highs and lows, but
still with no reason to think that any individuals would be taken a
significant portion of the days of the year, much less that many of the
days of disturbance would be sequential.
Physiological Stress Response
Some of the lower level physiological stress responses (e.g.,
orientation or startle response, change in respiration, change in heart
rate) discussed earlier would likely co-occur with the predicted
harassments, although these

[[Page 34008]]

responses are more difficult to detect and fewer data exist relating
these responses to specific received levels of sound. Level B
harassment takes, then, may have a stress-related physiological
component as well; however, we would not expect the Navy's generally
short-term, intermittent, and (typically in the case of sonar)
transitory activities to create conditions of long-term continuous
noise leading to long-term physiological stress responses in marine
mammals that could affect reproduction or survival.
Behavioral Response
The estimates calculated using the behavioral response function do
not differentiate between the different types of behavioral responses
that rise to the level of Level B harassments. As described in the
Navy's application, the Navy identified (with NMFS' input) the types of
behaviors that would be considered a take (moderate behavioral
responses as characterized in Southall et al. (2007) (e.g., altered
migration paths or dive profiles, interrupted nursing, breeding or
feeding, or avoidance) that also would be expected to continue for the
duration of an exposure). The Navy then compiled the available data
indicating at what received levels and distances those responses have
occurred, and used the indicated literature to build biphasic
behavioral response curves that are used to predict how many instances
of Level B behavioral harassment occur in a day. Take estimates alone
do not provide information regarding the potential fitness or other
biological consequences of the reactions on the affected individuals.
We therefore consider the available activity-specific, environmental,
and species-specific information to determine the likely nature of the
modeled behavioral responses and the potential fitness consequences for
affected individuals.
Use of sonar and other transducers would typically be transient and
temporary. The majority of acoustic effects to individual animals from
sonar and other active sound sources during training and testing
activities would be primarily from ASW events. Unlike other Navy
training and testing Study Areas, no major training exercises (MTEs)
are proposed in the NWTT Study Area. In the range of potential
behavioral effects that might expect to be part of a response that
qualifies as an instance of Level B behavioral harassment (which by
nature of the way it is modeled/counted, occurs within one day), the
less severe end might include exposure to comparatively lower levels of
a sound, at a detectably greater distance from the animal, for a few or
several minutes. A less severe exposure of this nature could result in
a behavioral response such as avoiding an area that an animal would
otherwise have chosen to move through or feed in for some amount of
time or breaking off one or a few feeding bouts. More severe effects
could occur when the animal gets close enough to the source to receive
a comparatively higher level of sound, is exposed continuously to one
source for a longer time, or is exposed intermittently to different
sources throughout a day. Such effects might result in an animal having
a more severe flight response and leaving a larger area for a day or
more or potentially losing feeding opportunities for a day. However,
such severe behavioral effects are expected to occur infrequently.
To help assess this, for sonar (LFAS/MFAS/HFAS) used in the NWTT
Study Area, the Navy provided information estimating the percentage of
animals that may be taken by Level B harassment under each behavioral
response function that would occur within 6-dB increments (percentages
discussed below in the Group and Species-Specific Analyses section). As
mentioned above, all else being equal, an animal's exposure to a higher
received level is more likely to result in a behavioral response that
is more likely to lead to adverse effects, which could more likely
accumulate to impacts on reproductive success or survivorship of the
animal, but other contextual factors (such as distance) are also
important. The majority of Level B harassment takes are expected to be
in the form of milder responses (i.e., lower-level exposures that still
rise to the level of take, but would likely be less severe in the range
of responses that qualify as take) of a generally shorter duration. We
anticipate more severe effects from takes when animals are exposed to
higher received levels of sound or at closer proximity to the source.
Because species belonging to taxa that share common characteristics are
likely to respond and be affected in similar ways, these discussions
are presented within each species group below in the Group and Species-
Specific Analyses section. As noted previously in this proposed rule,
behavioral response is likely highly variable between species,
individuals within a species, and context of the exposure.
Specifically, given a range of behavioral responses that may be
classified as Level B harassment, to the degree that higher received
levels of sound are expected to result in more severe behavioral
responses, only a smaller percentage of the anticipated Level B
harassment from Navy activities might necessarily be expected to
potentially result in more severe responses (see the Group and Species-
Specific Analyses section below for more detailed information). To
fully understand the likely impacts of the predicted/proposed
authorized take on an individual (i.e., what is the likelihood or
degree of fitness impacts), one must look closely at the available
contextual information, such as the duration of likely exposures and
the likely severity of the exposures (e.g., whether they will occur for
a longer duration over sequential days or the comparative sound level
that will be received). Ellison et al. (2012) and Moore and Barlow
(2013), among others emphasize the importance of context (e.g.,
behavioral state of the animals, distance from the sound source, etc.)
in evaluating behavioral responses of marine mammals to acoustic
sources.
Diel Cycle
Many animals perform vital functions, such as feeding, resting,
traveling, and socializing on a diel cycle (24-hour cycle). Behavioral
reactions to noise exposure, when taking place in a biologically
important context, such as disruption of critical life functions,
displacement, or avoidance of important habitat, are more likely to be
significant if they last more than one diel cycle or recur on
subsequent days (Southall et al., 2007). Henderson et al. (2016) found
that ongoing smaller scale events had little to no impact on foraging
dives for Blainville's beaked whale, while multi-day training events
may decrease foraging behavior for Blainville's beaked whale (Manzano-
Roth et al., 2016). Consequently, a behavioral response lasting less
than one day and not recurring on subsequent days is not considered
severe unless it could directly affect reproduction or survival
(Southall et al., 2007). Note that there is a difference between
multiple-day substantive behavioral reactions and multiple-day
anthropogenic activities. For example, just because an at-sea exercise
lasts for multiple days does not necessarily mean that individual
animals are either exposed to those exercises for multiple days or,
further, exposed in a manner resulting in a sustained multiple day
substantive behavioral response. Large multi-day Navy exercises such as
ASW activities, typically include vessels that are continuously moving
at speeds typically 10-15 kn, or higher, and likely cover large areas
that are relatively far from shore (typically more than 3 nmi from
shore) and in waters greater than 600 ft deep. Additionally marine
mammals are

[[Page 34009]]

moving as well, which would make it unlikely that the same animal could
remain in the immediate vicinity of the ship for the entire duration of
the exercise. Further, the Navy does not necessarily operate active
sonar the entire time during an exercise. While it is certainly
possible that these sorts of exercises could overlap with individual
marine mammals multiple days in a row at levels above those anticipated
to result in a take, because of the factors mentioned above, it is
considered unlikely for the majority of takes. However, it is also
worth noting that the Navy conducts many different types of noise-
producing activities over the course of the year and it is likely that
some marine mammals will be exposed to more than one activity and taken
on multiple days, even if they are not sequential.
Durations of Navy activities utilizing tactical sonar sources and
explosives vary and are fully described in Appendix A (Navy Activity
Descriptions) of the 2019 NWTT DSEIS/OEIS. Sonar used during ASW would
impart the greatest amount of acoustic energy of any category of sonar
and other transducers analyzed in the Navy's rulemaking/LOA application
and include hull-mounted, towed, line array, sonobuoy, helicopter
dipping, and torpedo sonars. Most ASW sonars are MFAS (1-10 kHz);
however, some sources may use higher or lower frequencies. ASW training
activities using hull mounted sonar proposed for the NWTT Study Area
generally last for only a few hours (see Table 3). Some ASW testing
activities range from several hours, to days, to up to 3 weeks for
Pierside-Sonar Testing and Submarine Sonar Testing/Maintenance (see
Table 4). For these multi-day exercises there will typically be
extended intervals of non-activity in between active sonar periods.
Because of the need to train in a large variety of situations, the Navy
does not typically conduct successive ASW exercises in the same
locations. Given the average length of ASW exercises (times of sonar
use) and typical vessel speed, combined with the fact that the majority
of the cetaceans would not likely remain in proximity to the sound
source, it is unlikely that an animal would be exposed to LFAS/MFAS/
HFAS at levels or durations likely to result in a substantive response
that would then be carried on for more than one day or on successive
days.
Most planned explosive events are scheduled to occur over a short
duration (1-8 hours); however Mine Countermeasure and Neutralization
Testing would last 1-10 days (see Tables 3 and 4). The explosive
component of these activities only lasts for minutes. Although
explosive exercises may sometimes be conducted in the same general
areas repeatedly, because of their short duration and the fact that
they are in the open ocean and animals can easily move away, it is
similarly unlikely that animals would be exposed for long, continuous
amounts of time, or demonstrate sustained behavioral responses. All of
these factors make it unlikely that individuals would be exposed to the
exercise for extended periods or on consecutive days.
Assessing the Number of Individuals Taken and the Likelihood of
Repeated Takes
As described previously, Navy modeling uses the best available
science to predict the instances of exposure above certain acoustic
thresholds, which are equated, as appropriate, to harassment takes (and
further corrected to account for mitigation and avoidance). As further
noted, for active acoustics it is more challenging to parse out the
number of individuals taken by Level B harassment and the number of
times those individuals are taken from this larger number of instances.
One method that NMFS uses to help better understand the overall scope
of the impacts is to compare these total instances of take against the
abundance of that species (or stock if applicable). For example, if
there are 100 harassment takes in a population of 100, one can assume
either that every individual was exposed above acoustic thresholds in
no more than one day, or that some smaller number were exposed in one
day but a few of those individuals were exposed multiple days within a
year and a few were not exposed at all. Where the instances of take
exceed 100 percent of the population, multiple takes of some
individuals are predicted and expected to occur within a year.
Generally speaking, the higher the number of takes as compared to the
population abundance, the more multiple takes of individuals are
likely, and the higher the actual percentage of individuals in the
population that are likely taken at least once in a year. We look at
this comparative metric to give us a relative sense of where larger
portions of the species are being taken by Navy activities and where
there is a higher likelihood that the same individuals are being taken
across multiple days and where that number of days might be higher. It
also provides a relative picture of the scale of impacts to each
species.
In the ocean, unlike a modeling simulation with static animals, the
use of sonar and other active acoustic sources is often transient, and
is unlikely to repeatedly expose the same individual animals within a
short period, for example within one specific exercise. However, some
repeated exposures across different activities could occur over the
year with more resident species. In short, we expect that the total
anticipated takes represent exposures of a smaller number of
individuals of which some could be exposed multiple times, but based on
the nature of the Navy's activities and the movement patterns of marine
mammals, it is unlikely that any particular subset would be taken over
more than several sequential days (with a few possible exceptions
discussed in the species-specific conclusions).
When calculating the proportion of a population affected by takes
(e.g., the number of takes divided by population abundance), which can
also be helpful in estimating the number of days over which some
individuals may be taken, it is important to choose an appropriate
population estimate against which to make the comparison. The SARs,
where available, provide the official population estimate for a given
species or stock in U.S. waters in a given year (and are typically
based solely on the most recent survey data). When the stock is known
to range well outside of U.S. Exclusive Economic Zone (EEZ) boundaries,
population estimates based on surveys conducted only within the U.S.
EEZ are known to be underestimates. The information used to estimate
take includes the best available survey abundance data to model density
layers. Accordingly, in calculating the percentage of takes versus
abundance for each species in order to assist in understanding both the
percentage of the species affected, as well as how many days across a
year individuals could be taken, we use the data most appropriate for
the situation. For all species and stocks except for a few stocks of
harbor seals for which SAR data are unavailable and Navy abundance
surveys of the inland areas of the NWTT Study Area are used, the most
recent NMFS SARs are used to calculate the proportion of a population
affected by takes.
The estimates found in NMFS' SARs remain the official estimates of
stock abundance where they are current. These estimates are typically
generated from the most recent shipboard and/or aerial surveys
conducted. In some cases, NMFS' abundance estimates show substantial
year-to-year variability. However, for highly migratory species (e.g.,
large whales) or those whose geographic distribution extends well

[[Page 34010]]

beyond the boundaries of the NWTT Study Area (e.g., populations with
distribution along the entire eastern Pacific Ocean rather than just
the NWTT Study Area), comparisons to the SAR are appropriate. Many of
the stocks present in the NWTT Study Area have ranges significantly
larger than the NWTT Study Area and that abundance is captured by the
SAR. A good descriptive example is migrating large whales, which
traverse the NWTT Study Area for several days to weeks on their
migrations. Therefore, at any one time there may be a stable number of
animals, but over the course of the entire year the entire population
may pass through the NWTT Study Area. Therefore, comparing the
estimated takes to an abundance, in this case the SAR abundance, which
represents the total population, may be more appropriate than modeled
abundances for only the NWTT Study Area.
Temporary Threshold Shift
NMFS and the Navy have estimated that all species of marine mammals
may sustain some level of TTS from active sonar. As mentioned
previously, in general, TTS can last from a few minutes to days, be of
varying degree, and occur across various frequency bandwidths, all of
which determine the severity of the impacts on the affected individual,
which can range from minor to more severe. Tables 52-57 indicate the
number of takes by TTS that may be incurred by different species from
exposure to active sonar and explosives. The TTS sustained by an animal
is primarily classified by three characteristics:
1. Frequency--Available data (of mid-frequency hearing specialists
exposed to mid- or high-frequency sounds; Southall et al., 2007)
suggest that most TTS occurs in the frequency range of the source up to
one octave higher than the source (with the maximum TTS at \1/2\ octave
above). The Navy's MF sources, which are the highest power and most
numerous sources and the ones that cause the most take, utilize the 1-
10 kHz frequency band, which suggests that if TTS were to be induced by
any of these MF sources it would be in a frequency band somewhere
between approximately 2 and 20 kHz, which is in the range of
communication calls for many odontocetes, but below the range of the
echolocation signals used for foraging. There are fewer hours of HF
source use and the sounds would attenuate more quickly, plus they have
lower source levels, but if an animal were to incur TTS from these
sources, it would cover a higher frequency range (sources are between
10 and 100 kHz, which means that TTS could range up to 200 kHz), which
could overlap with the range in which some odontocetes communicate or
echolocate. However, HF systems are typically used less frequently and
for shorter time periods than surface ship and aircraft MF systems, so
TTS from these sources is unlikely. There are fewer LF sources and the
majority are used in the more readily mitigated testing environment,
and TTS from LF sources would most likely occur below 2 kHz, which is
in the range where many mysticetes communicate and also where other
non-communication auditory cues are located (waves, snapping shrimp,
fish prey). Also of note, the majority of sonar sources from which TTS
may be incurred occupy a narrow frequency band, which means that the
TTS incurred would also be across a narrower band (i.e., not affecting
the majority of an animal's hearing range). This frequency provides
information about the cues to which a marine mammal may be temporarily
less sensitive, but not the degree or duration of sensitivity loss. TTS
from explosives would be broadband.
2. Degree of the shift (i.e., by how many dB the sensitivity of the
hearing is reduced)--Generally, both the degree of TTS and the duration
of TTS will be greater if the marine mammal is exposed to a higher
level of energy (which would occur when the peak dB level is higher or
the duration is longer). The threshold for the onset of TTS was
discussed previously in this rule. An animal would have to approach
closer to the source or remain in the vicinity of the sound source
appreciably longer to increase the received SEL, which would be
difficult considering the Lookouts and the nominal speed of an active
sonar vessel (10-15 kn) and the relative motion between the sonar
vessel and the animal. In the TTS studies discussed in the Potential
Effects of Specified Activities on Marine Mammals and their Habitat
section, some using exposures of almost an hour in duration or up to
217 SEL, most of the TTS induced was 15 dB or less, though Finneran et
al. (2007) induced 43 dB of TTS with a 64-second exposure to a 20 kHz
source. However, since any hull-mounted sonar such as the SQS-53
(MFAS), emits a ping typically every 50 seconds, incurring those levels
of TTS is highly unlikely. Since any hull-mounted sonar, such as the
SQS-53, engaged in anti-submarine warfare training would be moving at
between 10 and 15 knots and nominally pinging every 50 seconds, the
vessel will have traveled a minimum distance of approximately 257 m
during the time between those pings. A scenario could occur where an
animal does not leave the vicinity of a ship or travels a course
parallel to the ship, however, the close distances required make TTS
exposure unlikely. For a Navy vessel moving at a nominal 10 knots, it
is unlikely a marine mammal could maintain speed parallel to the ship
and receive adequate energy over successive pings to suffer TTS.
In short, given the anticipated duration and levels of sound
exposure, we would not expect marine mammals to incur more than
relatively low levels of TTS (i.e., single digits of sensitivity loss).
To add context to this degree of TTS, individual marine mammals may
regularly experience variations of 6 dB differences in hearing
sensitivity across time (Finneran et al., 2000, 2002; Schlundt et al.,
2000).
3. Duration of TTS (recovery time)--In the TTS laboratory studies
(as discussed in the Potential Effects of Specified Activities on
Marine Mammals and their Habitat section), some using exposures of
almost an hour in duration or up to 217 SEL, almost all individuals
recovered within 1 day (or less, often in minutes), although in one
study (Finneran et al., 2007), recovery took 4 days.
Based on the range of degree and duration of TTS reportedly induced
by exposures to non-pulse sounds of energy higher than that to which
free-swimming marine mammals in the field are likely to be exposed
during LFAS/MFAS/HFAS training and testing exercises in the NWTT Study
Area, it is unlikely that marine mammals would ever sustain a TTS from
MFAS that alters their sensitivity by more than 20 dB for more than a
few hours--and any incident of TTS would likely be far less severe due
to the short duration of the majority of the events and the speed of a
typical vessel, especially given the fact that the higher power sources
resulting in TTS are predominantly intermittent, which have been shown
to result in shorter durations of TTS. Also, for the same reasons
discussed in the Preliminary Analysis and Negligible Impact
Determination--Diel Cycle section, and because of the short distance
within which animals would need to approach the sound source, it is
unlikely that animals would be exposed to the levels necessary to
induce TTS in subsequent time periods such that their recovery is
impeded. Additionally, though the frequency range of TTS that marine
mammals might sustain would overlap with some of the frequency ranges
of their vocalization types, the frequency range of TTS from MFAS would
not usually span the entire

[[Page 34011]]

frequency range of one vocalization type, much less span all types of
vocalizations or other critical auditory cues.
Tables 52-57 indicate the number of incidental takes by TTS for
each species that are likely to result from the Navy's activities. As a
general point, the majority of these TTS takes are the result of
exposure to hull-mounted MFAS (MF narrower band sources), with fewer
from explosives (broad-band lower frequency sources), and even fewer
from LFAS or HFAS sources (narrower band). As described above, we
expect the majority of these takes to be in the form of mild (single-
digit), short-term (minutes to hours), narrower band (only affecting a
portion of the animal's hearing range) TTS. This means that for one to
several times per year, for several minutes to maybe a few hours at
most each, a taken individual will have slightly diminished hearing
sensitivity (slightly more than natural variation, but nowhere near
total deafness). More often than not, such an exposure would occur
within a narrower mid- to higher frequency band that may overlap part
(but not all) of a communication, echolocation, or predator range, but
sometimes across a lower or broader bandwidth. The significance of TTS
is also related to the auditory cues that are germane within the time
period that the animal incurs the TTS. For example, if an odontocete
has TTS at echolocation frequencies, but incurs it at night when it is
resting and not feeding, it is not impactful. In short, the expected
results of any one of these small number of mild TTS occurrences could
be that (1) it does not overlap signals that are pertinent to that
animal in the given time period, (2) it overlaps parts of signals that
are important to the animal, but not in a manner that impairs
interpretation, or (3) it reduces detectability of an important signal
to a small degree for a short amount of time--in which case the animal
may be aware and be able to compensate (but there may be slight
energetic cost), or the animal may have some reduced opportunities
(e.g., to detect prey) or reduced capabilities to react with maximum
effectiveness (e.g., to detect a predator or navigate optimally).
However, given the small number of times that any individual might
incur TTS, the low degree of TTS and the short anticipated duration,
and the low likelihood that one of these instances would occur in a
time period in which the specific TTS overlapped the entirety of a
critical signal, it is unlikely that TTS of the nature expected to
result from the Navy activities would result in behavioral changes or
other impacts that would impact any individual's (of any hearing
sensitivity) reproduction or survival.
Auditory Masking or Communication Impairment
The ultimate potential impacts of masking on an individual (if it
were to occur) are similar to those discussed for TTS, but an important
difference is that masking only occurs during the time of the signal,
versus TTS, which continues beyond the duration of the signal.
Fundamentally, masking is referred to as a chronic effect because one
of the key harmful components of masking is its duration--the fact that
an animal would have reduced ability to hear or interpret critical cues
becomes much more likely to cause a problem the longer it is occurring.
Also inherent in the concept of masking is the fact that the potential
for the effect is only present during the times that the animal and the
source are in close enough proximity for the effect to occur (and
further, this time period would need to coincide with a time that the
animal was utilizing sounds at the masked frequency). As our analysis
has indicated, because of the relative movement of vessels and the
species involved in this rule, we do not expect the exposures with the
potential for masking to be of a long duration. In addition, masking is
fundamentally more of a concern at lower frequencies, because low
frequency signals propagate significantly further than higher
frequencies and because they are more likely to overlap both the
narrower LF calls of mysticetes, as well as many non-communication cues
such as fish and invertebrate prey, and geologic sounds that inform
navigation. Masking is also more of a concern from continuous sources
(versus intermittent sonar signals) where there is no quiet time
between pulses within which auditory signals can be detected and
interpreted. For these reasons, dense aggregations of, and long
exposure to, continuous LF activity are much more of a concern for
masking, whereas comparatively short-term exposure to the predominantly
intermittent pulses of often narrow frequency range MFAS or HFAS, or
explosions are not expected to result in a meaningful amount of
masking. While the Navy occasionally uses LF and more continuous
sources, it is not in the contemporaneous aggregate amounts that would
accrue to a masking concern. Specifically, the nature of the activities
and sound sources used by the Navy do not support the likelihood of a
level of masking accruing that would have the potential to affect
reproductive success or survival. Additional detail is provided below.
Standard hull-mounted MFAS typically pings every 50 seconds. Some
hull-mounted anti-submarine sonars can also be used in an object
detection mode known as ``Kingfisher'' mode (e.g., used on vessels when
transiting to and from port) where pulse length is shorter but pings
are much closer together in both time and space since the vessel goes
slower when operating in this mode. For the majority of other sources,
the pulse length is significantly shorter than hull-mounted active
sonar, on the order of several microseconds to tens of milliseconds.
Some of the vocalizations that many marine mammals make are less than
one second long, so, for example with hull-mounted sonar, there would
be a 1 in 50 chance (only if the source was in close enough proximity
for the sound to exceed the signal that is being detected) that a
single vocalization might be masked by a ping. However, when
vocalizations (or series of vocalizations) are longer than one second,
masking would not occur. Additionally, when the pulses are only several
microseconds long, the majority of most animals' vocalizations would
not be masked.
Most ASW sonars and countermeasures use MF frequencies and a few
use LF and HF frequencies. Most of these sonar signals are limited in
the temporal, frequency, and spatial domains. The duration of most
individual sounds is short, lasting up to a few seconds each. A few
systems operate with higher duty cycles or nearly continuously, but
they typically use lower power, which means that an animal would have
to be closer, or in the vicinity for a longer time, to be masked to the
same degree as by a higher level source. Nevertheless, masking could
occasionally occur at closer ranges to these high-duty cycle and
continuous active sonar systems, but as described previously, it would
be expected to be of a short duration when the source and animal are in
close proximity. While data are lacking on behavioral responses of
marine mammals to continuously active sonars, mysticete species are
known to be able to habituate to novel and continuous sounds (Nowacek
et al., 2004), suggesting that they are likely to have similar
responses to high-duty cycle sonars. Furthermore, most of these systems
are hull-mounted on surface ships with the ships moving at least 10 kn,
and it is unlikely that the ship and the marine mammal would continue
to move in the same direction and the marine mammal subjected to the
same exposure due to that movement. Most

[[Page 34012]]

ASW activities are geographically dispersed and last for only a few
hours, often with intermittent sonar use even within this period. Most
ASW sonars also have a narrow frequency band (typically less than one-
third octave). These factors reduce the likelihood of sources causing
significant masking. HF signals (above 10 kHz) attenuate more rapidly
in the water due to absorption than do lower frequency signals, thus
producing only a very small zone of potential masking. If masking or
communication impairment were to occur briefly, it would more likely be
in the frequency range of MFAS (the more powerful source), which
overlaps with some odontocete vocalizations (but few mysticete
vocalizations); however, it would likely not mask the entirety of any
particular vocalization, communication series, or other critical
auditory cue, because the signal length, frequency, and duty cycle of
the MFAS/HFAS signal does not perfectly resemble the characteristics of
any single marine mammal species' vocalizations.
Other sources used in Navy training and testing that are not
explicitly addressed above, many of either higher frequencies (meaning
that the sounds generated attenuate even closer to the source) or lower
amounts of operation, are similarly not expected to result in masking.
For the reasons described here, any limited masking that could
potentially occur would be minor and short-term.
In conclusion, masking is more likely to occur in the presence of
broadband, relatively continuous noise sources such as from vessels,
however, the duration of temporal and spatial overlap with any
individual animal and the spatially separated sources that the Navy
uses would not be expected to result in more than short-term, low
impact masking that would not affect reproduction or survival.
PTS from Sonar Acoustic Sources and Explosives and Tissue Damage from
Explosives
Tables 52 through 57 indicate the number of individuals of each
species for which Level A harassment in the form of PTS resulting from
exposure to active sonar and/or explosives is estimated to occur. The
number of individuals to potentially incur PTS annually (from sonar and
explosives) for each species/stock ranges from 0 to 180 (the 180 is for
the Inland Washington stock of harbor porpoise), but is more typically
0 or 1. No species/stocks have the potential to incur tissue damage
from sonar or explosives.
Data suggest that many marine mammals would deliberately avoid
exposing themselves to the received levels of active sonar necessary to
induce injury by moving away from or at least modifying their path to
avoid a close approach. Additionally, in the unlikely event that an
animal approaches the sonar-emitting vessel at a close distance, NMFS
has determined that the mitigation measures (i.e., shutdown/powerdown
zones for active sonar) would typically ensure that animals would not
be exposed to injurious levels of sound. As discussed previously, the
Navy utilizes both aerial (when available) and passive acoustic
monitoring (during ASW exercises, passive acoustic detections are used
as a cue for Lookouts' visual observations when passive acoustic assets
are already participating in an activity) in addition to Lookouts on
vessels to detect marine mammals for mitigation implementation. As
discussed previously, the Navy utilized a post-modeling quantitative
assessment to adjust the take estimates based on avoidance and the
likely success of some portion of the mitigation measures. As is
typical in predicting biological responses, it is challenging to
predict exactly how avoidance and mitigation will affect the take of
marine mammals, and therefore the Navy erred on the side of caution in
choosing a method that would more likely still overestimate the take by
PTS to some degree. Nonetheless, these modified Level A harassment take
numbers represent the maximum number of instances in which marine
mammals would be reasonably expected to incur PTS, and we have analyzed
them accordingly.
If a marine mammal is able to approach a surface vessel within the
distance necessary to incur PTS in spite of the mitigation measures,
the likely speed of the vessel (nominally 10-15 kn) and relative motion
of the vessel would make it very difficult for the animal to remain in
range long enough to accumulate enough energy to result in more than a
mild case of PTS. As discussed previously in relation to TTS, the
likely consequences to the health of an individual that incurs PTS can
range from mild to more serious dependent upon the degree of PTS and
the frequency band it is in. The majority of any PTS incurred as a
result of exposure to Navy sources would be expected to be in the 2-20
kHz range (resulting from the most powerful hull-mounted sonar) and
could overlap a small portion of the communication frequency range of
many odontocetes, whereas other marine mammal groups have communication
calls at lower frequencies. Regardless of the frequency band, the more
important point in this case is that any PTS accrued as a result of
exposure to Navy activities would be expected to be of a small amount
(single digits). Permanent loss of some degree of hearing is a normal
occurrence for older animals, and many animals are able to compensate
for the shift, both in old age or at younger ages as the result of
stressor exposure. While a small loss of hearing sensitivity may
include some degree of energetic costs for compensating or may mean
some small loss of opportunities or detection capabilities, at the
expected scale it would be unlikely to impact behaviors, opportunities,
or detection capabilities to a degree that would interfere with
reproductive success or survival.
The Navy implements mitigation measures (described in the Proposed
Mitigation Measures section) during explosive activities, including
delaying detonations when a marine mammal is observed in the mitigation
zone. Nearly all explosive events would occur during daylight hours to
improve the sightability of marine mammals and thereby improve
mitigation effectiveness. Observing for marine mammals during the
explosive activities would include visual and passive acoustic
detection methods (when they are available and part of the activity)
before the activity begins, in order to cover the mitigation zones that
can range from 600 yds (656 m) to 2,500 yds (2,286 m) depending on the
source (e.g., explosive sonobuoy, explosive torpedo, explosive bombs;
see Tables 38-44). For all of these reasons, the proposed mitigation
measures associated with explosives are expected to be effective in
preventing tissue damage to any potentially affected species, and no
species are anticipated to incur tissue damage during the period of the
proposed rule.
Serious Injury and Mortality
NMFS is authorizing a very small number of serious injuries or
mortalities that could occur in the event of a ship strike. We note
here that the takes from potential ship strikes enumerated below could
result in non-serious injury, but their worst potential outcome
(mortality) is analyzed for the purposes of the negligible impact
determination.
In addition, we discuss here the connection, and differences,
between the legal mechanisms for authorizing incidental take under
section 101(a)(5) for activities such as the Navy's testing and
training in the NWTT Study Area, and for authorizing incidental take
from commercial fisheries. In 1988, Congress amended the MMPA's
provisions for

[[Page 34013]]

addressing incidental take of marine mammals in commercial fishing
operations. Congress directed NMFS to develop and recommend a new long-
term regime to govern such incidental taking (see MMC, 1994). The need
to develop a system suited to the unique circumstances of commercial
fishing operations led NMFS to suggest a new conceptual means and
associated regulatory framework. That concept, PBR, and a system for
developing plans containing regulatory and voluntary measures to reduce
incidental take for fisheries that exceed PBR were incorporated as
sections 117 and 118 in the 1994 amendments to the MMPA. In
Conservation Council for Hawaii v. National Marine Fisheries Service,
97 F. Supp. 3d 1210 (D. Haw. 2015), which concerned a challenge to
NMFS' regulations and LOAs to the Navy for activities assessed in the
2013-2018 HSTT MMPA rulemaking, the Court ruled that NMFS' failure to
consider PBR when evaluating lethal takes in the negligible impact
analysis under section 101(a)(5)(A) violated the requirement to use the
best available science.
PBR is defined in section 3 of the MMPA as ``the maximum number of
animals, not including natural mortalities, that may be removed from a
marine mammal stock while allowing that stock to reach or maintain its
optimum sustainable population'' (OSP) and, although not controlling,
can be one measure considered among other factors when evaluating the
effects of M/SI on a marine mammal species or stock during the section
101(a)(5)(A) process. OSP is defined in section 3 of the MMPA as ``the
number of animals which will result in the maximum productivity of the
population or the species, keeping in mind the carrying capacity of the
habitat and the health of the ecosystem of which they form a
constituent element.'' Through section 2, an overarching goal of the
statute is to ensure that each species or stock of marine mammal is
maintained at or returned to its OSP.
PBR values are calculated by NMFS as the level of annual removal
from a stock that will allow that stock to equilibrate within OSP at
least 95 percent of the time, and is the product of factors relating to
the minimum population estimate of the stock (Nmin), the
productivity rate of the stock at a small population size, and a
recovery factor. Determination of appropriate values for these three
elements incorporates significant precaution, such that application of
the parameter to the management of marine mammal stocks may be
reasonably certain to achieve the goals of the MMPA. For example,
calculation of the minimum population estimate (Nmin)
incorporates the level of precision and degree of variability
associated with abundance information, while also providing reasonable
assurance that the stock size is equal to or greater than the estimate
(Barlow et al., 1995), typically by using the 20th percentile of a log-
normal distribution of the population estimate. In general, the three
factors are developed on a stock-specific basis in consideration of one
another in order to produce conservative PBR values that appropriately
account for both imprecision that may be estimated, as well as
potential bias stemming from lack of knowledge (Wade, 1998).
Congress called for PBR to be applied within the management
framework for commercial fishing incidental take under section 118 of
the MMPA. As a result, PBR cannot be applied appropriately outside of
the section 118 regulatory framework without consideration of how it
applies within the section 118 framework, as well as how the other
statutory management frameworks in the MMPA differ from the framework
in section 118. PBR was not designed and is not used as an absolute
threshold limiting commercial fisheries. Rather, it serves as a means
to evaluate the relative impacts of those activities on marine mammal
stocks. Even where commercial fishing is causing M/SI at levels that
exceed PBR, the fishery is not suspended. When M/SI exceeds PBR in the
commercial fishing context under section 118, NMFS may develop a take
reduction plan, usually with the assistance of a take reduction team.
The take reduction plan will include measures to reduce and/or minimize
the taking of marine mammals by commercial fisheries to a level below
the stock's PBR. That is, where the total annual human-caused M/SI
exceeds PBR, NMFS is not required to halt fishing activities
contributing to total M/SI but rather utilizes the take reduction
process to further mitigate the effects of fishery activities via
additional bycatch reduction measures. In other words, under section
118 of the MMPA, PBR does not serve as a strict cap on the operation of
commercial fisheries that may incidentally take marine mammals.
Similarly, to the extent PBR may be relevant when considering the
impacts of incidental take from activities other than commercial
fisheries, using it as the sole reason to deny (or issue) incidental
take authorization for those activities would be inconsistent with
Congress's intent under section 101(a)(5), NMFS' long-standing
regulatory definition of ``negligible impact,'' and the use of PBR
under section 118. The standard for authorizing incidental take for
activities other than commercial fisheries under section 101(a)(5)
continues to be, among other things that are not related to PBR,
whether the total taking will have a negligible impact on the species
or stock. Nowhere does section 101(a)(5)(A) reference use of PBR to
make the negligible impact finding or authorize incidental take through
multi-year regulations, nor does its companion provision at
101(a)(5)(D) for authorizing non-lethal incidental take under the same
negligible-impact standard. NMFS' MMPA implementing regulations state
that take has a negligible impact when it does not ``adversely affect
the species or stock through effects on annual rates of recruitment or
survival''--likewise without reference to PBR. When Congress amended
the MMPA in 1994 to add section 118 for commercial fishing, it did not
alter the standards for authorizing non-commercial fishing incidental
take under section 101(a)(5), implicitly acknowledging that the
negligible impact standard under section 101(a)(5) is separate from the
PBR metric under section 118. In fact, in 1994 Congress also amended
section 101(a)(5)(E) (a separate provision governing commercial fishing
incidental take for species listed under the ESA) to add compliance
with the new section 118 but retained the standard of the negligible
impact finding under section 101(a)(5)(A) (and section 101(a)(5)(D)),
showing that Congress understood that the determination of negligible
impact and application of PBR may share certain features but are, in
fact, different.
Since the introduction of PBR in 1994, NMFS had used the concept
almost entirely within the context of implementing sections 117 and 118
and other commercial fisheries management-related provisions of the
MMPA. Prior to the Court's ruling in Conservation Council for Hawaii v.
National Marine Fisheries Service and consideration of PBR in a series
of section 101(a)(5) rulemakings, there were a few examples where PBR
had informed agency deliberations under other MMPA sections and
programs, such as playing a role in the issuance of a few scientific
research permits and subsistence takings. But as the Court found when
reviewing examples of past PBR consideration in Georgia Aquarium v.
Pritzker, 135 F. Supp. 3d 1280 (N.D. Ga. 2015), where NMFS had
considered PBR outside the commercial fisheries context, ``it has
treated PBR as only one `quantitative tool' and [has not used it]

[[Page 34014]]

as the sole basis for its impact analyses.'' Further, the agency's
thoughts regarding the appropriate role of PBR in relation to MMPA
programs outside the commercial fishing context have evolved since the
agency's early application of PBR to section 101(a)(5) decisions.
Specifically, NMFS' denial of a request for incidental take
authorization for the U.S. Coast Guard in 1996 seemingly was based on
the potential for lethal take in relation to PBR and did not appear to
consider other factors that might also have informed the potential for
ship strike in relation to negligible impact (61 FR 54157; October 17,
1996).
The MMPA requires that PBR be estimated in SARs and that it be used
in applications related to the management of take incidental to
commercial fisheries (i.e., the take reduction planning process
described in section 118 of the MMPA and the determination of whether a
stock is ``strategic'' as defined in section 3), but nothing in the
statute requires the application of PBR outside the management of
commercial fisheries interactions with marine mammals. Nonetheless,
NMFS recognizes that as a quantitative metric, PBR may be useful as a
consideration when evaluating the impacts of other human-caused
activities on marine mammal stocks. Outside the commercial fishing
context, and in consideration of all known human-caused mortality, PBR
can help inform the potential effects of M/SI requested to be
authorized under 101(a)(5)(A). As noted by NMFS and the U.S. Fish and
Wildlife Service in our implementation regulations for the 1986
amendments to the MMPA (54 FR 40341, September 29, 1989), the Services
consider many factors, when available, in making a negligible impact
determination, including, but not limited to, the status of the species
or stock relative to OSP (if known); whether the recruitment rate for
the species or stock is increasing, decreasing, stable, or unknown; the
size and distribution of the population; and existing impacts and
environmental conditions. In this multi-factor analysis, PBR can be a
useful indicator for when, and to what extent, the agency should take
an especially close look at the circumstances associated with the
potential mortality, along with any other factors that could influence
annual rates of recruitment or survival.
When considering PBR during evaluation of effects of M/SI under
section 101(a)(5)(A), we first calculate a metric for each species or
stock that incorporates information regarding ongoing anthropogenic M/
SI from all sources into the PBR value (i.e., PBR minus the total
annual anthropogenic mortality/serious injury estimate in the SAR),
which is called ``residual PBR.'' (Wood et al., 2012). We first focus
our analysis on residual PBR because it incorporates anthropogenic
mortality occurring from other sources. If the ongoing human-caused
mortality from other sources does not exceed PBR, then residual PBR is
a positive number, and we consider how the anticipated or potential
incidental M/SI from the activities being evaluated compares to
residual PBR using the framework in the following paragraph. If the
ongoing anthropogenic mortality from other sources already exceeds PBR,
then residual PBR is a negative number and we consider the M/SI from
the activities being evaluated as described further below.
When ongoing total anthropogenic mortality from the applicant's
specified activities does not exceed PBR and residual PBR is a positive
number, as a simplifying analytical tool we first consider whether the
specified activities could cause incidental M/SI that is less than 10
percent of residual PBR (the ``insignificance threshold,'' see below).
If so, we consider M/SI from the specified activities to represent an
insignificant incremental increase in ongoing anthropogenic M/SI for
the marine mammal stock in question that alone (i.e., in the absence of
any other take) will not adversely affect annual rates of recruitment
and survival. As such, this amount of M/SI would not be expected to
affect rates of recruitment or survival in a manner resulting in more
than a negligible impact on the affected stock unless there are other
factors that could affect reproduction or survival, such as Level A
and/or Level B harassment, or other considerations such as information
that illustrates uncertainty involved in the calculation of PBR for
some stocks. In a few prior incidental take rulemakings, this threshold
was identified as the ``significance threshold,'' but it is more
accurately labeled an insignificance threshold, and so we use that
terminology here. Assuming that any additional incidental take by Level
A or Level B harassment from the activities in question would not
combine with the effects of the authorized M/SI to exceed the
negligible impact level, the anticipated M/SI caused by the activities
being evaluated would have a negligible impact on the species or stock.
However, M/SI above the 10 percent insignificance threshold does not
indicate that the M/SI associated with the specified activities is
approaching a level that would necessarily exceed negligible impact.
Rather, the 10 percent insignificance threshold is meant only to
identify instances where additional analysis of the anticipated M/SI is
not required because the negligible impact standard clearly will not be
exceeded on that basis alone.
Where the anticipated M/SI is near, at, or above residual PBR,
consideration of other factors (positive or negative), including those
outlined above, as well as mitigation is especially important to
assessing whether the M/SI will have a negligible impact on the species
or stock. PBR is a conservative metric and not sufficiently precise to
serve as an absolute predictor of population effects upon which
mortality caps would appropriately be based. For example, in some cases
stock abundance (which is one of three key inputs into the PBR
calculation) is underestimated because marine mammal survey data within
the U.S. EEZ are used to calculate the abundance even when the stock
range extends well beyond the U.S. EEZ. An underestimate of abundance
could result in an underestimate of PBR. Alternatively, we sometimes
may not have complete M/SI data beyond the U.S. EEZ to compare to PBR,
which could result in an overestimate of residual PBR. The accuracy and
certainty around the data that feed any PBR calculation, such as the
abundance estimates, must be carefully considered to evaluate whether
the calculated PBR accurately reflects the circumstances of the
particular stock. M/SI that exceeds PBR may still potentially be found
to be negligible in light of other factors that offset concern,
especially when robust mitigation and adaptive management provisions
are included.
In Conservation Council for Hawaii v. National Marine Fisheries
Service, which involved the challenge to NMFS' issuance of LOAs to the
Navy in 2013 for activities in the HSTT Study Area, the Court reached a
different conclusion, stating, ``Because any mortality level that
exceeds PBR will not allow the stock to reach or maintain its OSP, such
a mortality level could not be said to have only a `negligible impact'
on the stock.'' As described above, the Court's statement fundamentally
misunderstands the two terms and incorrectly indicates that these
concepts (PBR and ``negligible impact'') are directly connected, when
in fact nowhere in the MMPA is it indicated that these two terms are
equivalent.
Specifically, PBR was designed as a tool for evaluating mortality
and is defined as the number of animals that

[[Page 34015]]

can be removed while ``allowing that stock to reach or maintain its
[OSP].'' OSP is defined as a population that falls within a range from
the population level that is the largest supportable within the
ecosystem to the population level that results in maximum net
productivity, and thus is an aspirational management goal of the
overall statute with no specific timeframe by which it should be met.
PBR is designed to ensure minimal deviation from this overarching goal,
with the formula for PBR typically ensuring that growth towards OSP is
not reduced by more than 10 percent (or equilibrates to OSP 95 percent
of the time). As PBR is applied by NMFS, it provides that growth toward
OSP is not reduced by more than 10 percent, which certainly allows a
stock to ``reach or maintain its [OSP]'' in a conservative and
precautionary manner--and we can therefore clearly conclude that if PBR
were not exceeded, there would not be adverse effects on the affected
species or stocks. Nonetheless, it is equally clear that in some cases
the time to reach this aspirational OSP level could be slowed by more
than 10 percent (i.e., total human-caused mortality in excess of PBR
could be allowed) without adversely affecting a species or stock
through effects on its rates of recruitment or survival. Thus even in
situations where the inputs to calculate PBR are thought to accurately
represent factors such as the species' or stock's abundance or
productivity rate, it is still possible for incidental take to have a
negligible impact on the species or stock even where M/SI exceeds
residual PBR or PBR.
As noted above, in some cases the ongoing human-caused mortality
from activities other than those being evaluated already exceeds PBR
and, therefore, residual PBR is negative. In these cases (such as is
specifically discussed for the CA/OR/WA stock of humpback whales
below), any additional mortality, no matter how small, and no matter
how small relative to the mortality caused by other human activities,
would result in greater exceedance of PBR. PBR is helpful in informing
the analysis of the effects of mortality on a species or stock because
it is important from a biological perspective to be able to consider
how the total mortality in a given year may affect the population.
However, section 101(a)(5)(A) of the MMPA indicates that NMFS shall
authorize the requested incidental take from a specified activity if we
find that ``the total of such taking [i.e., from the specified
activity] will have a negligible impact on such species or stock.'' In
other words, the task under the statute is to evaluate the applicant's
anticipated take in relation to their take's impact on the species or
stock, not other entities' impacts on the species or stock. Neither the
MMPA nor NMFS' implementing regulations call for consideration of other
unrelated activities and their impacts on the species or stock. In
fact, in response to public comments on the implementing regulations
NMFS explained that such effects are not considered in making
negligible impact findings under section 101(a)(5), although the extent
to which a species or stock is being impacted by other anthropogenic
activities is not ignored. Such effects are reflected in the baseline
of existing impacts as reflected in the species' or stock's abundance,
distribution, reproductive rate, and other biological indicators.
NMFS guidance for commercial fisheries provides insight when
evaluating the effects of an applicant's incidental take as compared to
the incidental take caused by other entities. Parallel to section
101(a)(5)(A), section 101(a)(5)(E) of the MMPA provides that NMFS shall
allow the incidental take of ESA-listed endangered or threatened marine
mammals by commercial fisheries if, among other things, the incidental
M/SI from the commercial fisheries will have a negligible impact on the
species or stock. As discussed earlier, the authorization of incidental
take resulting from commercial fisheries and authorization for
activities other than commercial fisheries are under two separate
regulatory frameworks. However, when it amended the statute in 1994 to
provide a separate incidental take authorization process for commercial
fisheries, Congress kept the requirement of a negligible impact
determination for this one category of species, thereby applying the
standard to both programs. Therefore, while the structure and other
standards of the two programs differ such that evaluation of negligible
impact under one program may not be fully applicable to the other
program (e.g., the regulatory definition of ``negligible impact'' at 50
CFR 216.103 applies only to activities other than commercial fishing),
guidance on determining negligible impact for commercial fishing take
authorizations can be informative when considering incidental take
outside the commercial fishing context. In 1999, NMFS published
criteria for making a negligible impact determination pursuant to
section 101(a)(5)(E) of the MMPA in a notice of proposed permits for
certain fisheries (64 FR 28800; May 27, 1999). Criterion 2 stated if
total human-related serious injuries and mortalities are greater than
PBR, and fisheries-related mortality is less than 0.1 PBR, individual
fisheries may be permitted if management measures are being taken to
address non-fisheries-related serious injuries and mortalities. When
fisheries-related serious injury and mortality is less than 10 percent
of the total, the appropriate management action is to address
components that account for the major portion of the total. This
criterion addresses when total human-caused mortality is exceeding PBR,
but the activity being assessed is responsible for only a small portion
of the mortality. The analytical framework we use here appropriately
incorporates elements of the one developed for use under section
101(a)(5)(E) and because the negligible impact determination under
section 101(a)(5)(A) focuses on the activity being evaluated, it is
appropriate to utilize the parallel concept from the framework for
section 101(a)(5)(E).
Accordingly, we are using a similar criterion in our negligible
impact analysis under section 101(a)(5)(A) to evaluate the relative
role of an applicant's incidental take when other sources of take are
causing PBR to be exceeded, but the take of the specified activity is
comparatively small. Where this occurs, we may find that the impacts of
the taking from the specified activity may (those impacts alone, before
we have considered the combined effects from any harassment take) be
negligible even when total human-caused mortality from all activities
exceeds PBR if (in the context of a particular species or stock): The
authorized mortality or serious injury would be less than or equal to
10 percent of PBR and management measures are being taken to address
serious injuries and mortalities from the other activities (i.e., other
than the specified activities covered by the incidental take
authorization under consideration). We must also determine, though,
that impacts on the species or stock from other types of take (i.e.,
harassment) caused by the applicant do not combine with the impacts
from mortality or serious injury to result in adverse effects on the
species or stock through effects on annual rates of recruitment or
survival.
As discussed above, however, while PBR is useful in informing the
evaluation of the effects of M/SI in section 101(a)(5)(A)
determinations, it is just one consideration to be assessed in
combination with other factors and is not determinative, including
because, as explained above, the accuracy and certainty of the data
used to calculate PBR for the species or stock must be

[[Page 34016]]

considered. And we reiterate the considerations discussed above for why
it is not appropriate to consider PBR an absolute cap in the
application of this guidance. Accordingly, we use PBR as a trigger for
concern while also considering other relevant factors to provide a
reasonable and appropriate means of evaluating the effects of potential
mortality on rates of recruitment and survival, while acknowledging
that it is possible to exceed PBR (or exceed 10 percent of PBR in the
case where other human-caused mortality is exceeding PBR but the
specified activity being evaluated is an incremental contributor, as
described in the last paragraph) by some small amount and still make a
negligible impact determination under section 101(a)(5)(A).
Our evaluation of the M/SI for each of the species and stocks for
which mortality or serious injury could occur follows. No M/SI are
anticipated from the Navy's sonar activities or use of explosives. We
first consider maximum potential incidental M/SI from the Navy's ship
strike analysis for the affected mysticetes and sperm whales (see Table
51) in consideration of NMFS' threshold for identifying insignificant
M/SI take. By considering the maximum potential incidental M/SI in
relation to PBR and ongoing sources of anthropogenic mortality, we
begin our evaluation of whether the potential incremental addition of
M/SI through Navy's ship strikes may affect the species' or stocks'
annual rates of recruitment or survival. We also consider the
interaction of those mortalities with incidental taking of that species
or stock by harassment pursuant to the specified activity.
Based on the methods discussed previously, NMFS believes that
mortal takes of three large whales may occur over the course of the
seven-year rule. Of the three total M/SI takes, the rule would
authorize no more than two from any of the following species/stocks
over the seven-year period: Fin whale (which may come from either the
Northeast Pacific or CA/OR/WA stock) and humpback whale (which may come
from either the Central North Pacific or CA/OR/WA stock). Of the three
total M/SI takes, the rule also would authorize no more than one
mortality from any of the following species/stocks over the seven-year
period: Sperm whale (CA/OR/WA stock), minke whale (CA/OR/WA stock), and
gray whale (Eastern North Pacific stock). We do not anticipate, nor
authorize, ship strike takes to blue whale (Eastern North Pacific
stock), minke whale (Alaska stock), or sei whale (Eastern North Pacific
stock). This means an annual average of 0.14 whales from each species
or stock where one mortality may occur and an annual average of 0.29
whales from each species or stock where two mortalities may occur, as
described in Table 51, is proposed for authorization (i.e., 1 or 2
takes over 7 years divided by 7 to get the annual number).

Table 51--Summary Information related to Mortalities Requested for Ship Strike, 2020-2027
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Annual
proposed Fisheries Vessel Residual
NWTT interactions collisions Annual Navy PBR-PBR
authorized Total (Y/N); (Y/N); HSTT minus Recent UME (Y/
Species (stock) Stock abundance (Nbest) take by annual M/ annual rate annual rate authorized PBR * annual M/ Stock trend \*4\ N); number
* serious SI * \2\ of M/SI from of M/SI take (2018- SI and and year
injury or fisheries from 2023) \5\ HSTT (since 2007)
mortality interactions vessel authorized
\1\ * collision * take \3\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Fin whale (Northeast Pacific)......... 3,168.................... 0.29 0.4 N; 0 Y; 0.4 0 5.1 4.7 [uarr].................. N
Fin whale (CA/OR/WA).................. 9,029.................... 0.29 >=43.5 Y; >=0.5 Y; 43 0.4 81 37.1 [uarr].................. N
Humpback whale (Central North Pacific) 10,103................... 0.29 25 Y; 9.5 \6\ Y; 3.9 0.4 83 57.6 [uarr].................. N
Humpback whale (CA/OR/WA)............. 2,900.................... 0.29 >=42.1 Y; >=17.3 Y; 22 0.2 33.4 -8.9 Stable ([uarr] N
(historically).
Sperm whale (CA/OR/WA)................ 1,997.................... 0.14 0.4 Y; 0.4 N; 0 0 2.5 2.1 Unknown................. N
Minke whale (CA/OR/WA)................ 636...................... 0.14 >=1.3 Y; >=1.3 N; 0 0 3.5 2.2 Unknown................. N
Gray whale (Eastern North Pacific).... 26,960................... 0.14 139 Y; 9.6 Y; 0.8 0.4 801 661.6 [uarr].................. Y, 264, 2019
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the 2019 draft SARs or most recent SAR.
\1\ This column represents the annual take by serious injury or mortality by vessel collision and was calculated by the number of mortalities proposed for authorization divided by seven years
(the length of the rule and LOAs).
\2\ This column represents the total number of incidents of M/SI that could potentially accrue to the specified species or stock. This number comes from the SAR, but deducts the takes accrued
from either NMFS Science Center research activities or Navy strikes authorized for training and testing activities. No NMFS Science Center or Navy M/SI takes for these stocks are recorded in
the SARs and no NMFS Science Center M/SI incidental takes have been authorized.
\3\ This value represents the calculated PBR minus the average annual estimate of ongoing anthropogenic mortalities (i.e., total annual human-caused M/SI column and the annual authorized take
from the HSTT column). This value represents the total PBR for the stock in the stock's entire range.
\4\ See relevant SARs for more information regarding stock status and trends.
\5\ This column represents annual M/SI take authorized through NMFS' current 5-year HSTT regulations/LOAs (83 FR 66846). Note that NMFS has proposed to replace the current HSTT regulations
with 7-year regulations (84 FR 48388) which propose to authorize the same number of M/SI for the same species/stocks, but over a 7-year period rather than a 5-year period (resulting in
slightly lower annual authorized take for each species/stock).
\6\ This value represents average annual observed M/SI from ship strikes in Alaska (2.5) and Hawaii (1.4). For the purposes of analysis of potential ship strike (see the Estimated Takes
section) we incorporated only Alaska ship strikes as only these ship strikes have the potential to overlap with the NWTT Study Area.

Stocks With M/SI Below the Insignificance Threshold

As noted above, for a species or stock with incidental M/SI less
than 10 percent of residual PBR, we consider M/SI from the specified
activities to represent an insignificant incremental increase in
ongoing anthropogenic M/SI that alone (i.e., in the absence of any
other take and barring any other unusual circumstances) will clearly
not adversely affect annual rates of recruitment and survival. In this
case, as shown in Table 51, the following species or stocks have
potential M/SI from ship strike proposed for authorization below their
insignificance threshold: Fin whale (both the Northeast Pacific and CA/
OR/WA stocks), humpback whale (Central North Pacific stock), sperm
whale (CA/OR/WA stock), minke whale (CA/OR/WA stock), and gray whale
(Eastern North Pacific stock). While the M/SI proposed for
authorization of gray whales (Eastern North Pacific stock) is below the
insignificance threshold, because of the recent UME, we further address
how the authorized M/SI and the UME inform the negligible impact
determination immediately below. For the other five stocks with M/SI
proposed for authorization below the insignificance threshold, there
are no other known factors, information, or unusual circumstances that
indicate anticipated M/SI below the insignificance threshold could have
adverse effects on annual rates of recruitment or survival and they

[[Page 34017]]

are not discussed further. For the remaining one stock (CA/OR/WA stock
of humpback whales) with potential M/SI above the insignificance
threshold, how that M/SI compares to residual PBR, as well as
additional factors, are discussed below as well.

Gray Whales (Eastern North Pacific Stock)

For this stock, PBR is currently set at 801. The total annual M/SI
from other sources of anthropogenic mortality is estimated to be 139.
In addition, 0.4 annual mortalities have been authorized for this same
stock in the current incidental take regulations for Navy testing and
training activities in the HSTT Study Area. This yields a residual PBR
of 661.6. The additional 0.29 annual mortalities that are proposed for
authorization in this rule are well below the insignificance threshold
(10 percent of residual PBR, in this case 66.16). Nonetheless, since
January 2019, gray whale strandings along the west coast of North
America have been significantly higher than the previous 18-year
average. Preliminary findings from necropsies have shown evidence of
poor to thin body condition. The seasonal pattern of elevated
strandings in the spring and summer months is similar to that of the
previous gray whale UME in 1999-2000. Current total monthly strandings
are slightly higher than 1999 and lower than 2000. If strandings
continue to follow a similar pattern, we would anticipate a decrease in
strandings in late summer and fall. However, combined with other annual
human-caused mortalities, and viewed through the PBR lens (for human-
caused mortalities), total human-caused mortality (inclusive of the
potential for additional UME deaths) would still fall well below
residual PBR and the insignificance threshold. Because of the
abundance, population trend (increasing, despite the UME in 1999-2000),
and residual PBR (661.6) of this stock, this UME is not expected to
have impacts on the population rate that, in combination with the
effects of mortality proposed to be authorized, would affect annual
rates of recruitment or survival.
Stocks With M/SI Above the Insignificance Threshold

Humpback Whale (CA/OR/WA Stock)

For this stock, PBR is currently set at 16.7 for U.S. waters and
33.4 for the stock's entire range. The total annual M/SI is estimated
at greater than or equal to 42.1. Combined with 0.2 annual mortalities
that have been authorized for this same stock in the current incidental
take regulations for Navy testing and training activities in the HSTT
Study Area, this yields a residual PBR of -8.9. NMFS proposes to
authorize up to 2 M/SI takes over the seven-year duration of this rule,
which would be 0.29 M/SI takes annually for the purposes of comparing
to PBR and considering other possible effects on annual rates of
recruitment and survival. This means that with the additional 0.29 M/SI
annual takes proposed in this rule, residual PBR would be exceeded by
9.19.
In the commercial fisheries setting for ESA-listed marine mammals
(which is similar to the non-fisheries incidental take setting, in that
a negligible impact determination is required that is based on the
assessment of take caused by the activity being analyzed) NMFS may find
the impact of the authorized take from a specified activity to be
negligible even if total human-caused mortality exceeds PBR, if the
authorized mortality is less than 10 percent of PBR and management
measures are being taken to address serious injuries and mortalities
from the other activities causing mortality (i.e., other than the
specified activities covered by the incidental take authorization under
consideration). When those considerations are applied in the section
101(a)(5)(A) context here, the proposed authorized lethal take (0.29
annually) of humpback whales from the CA/OR/WA stock is significantly
less than 10 percent of PBR (in fact less than 1 percent of 33.4) and
there are management measures in place to address M/SI from activities
other than those the Navy is conducting (as discussed below).
Based on identical simulations as those conducted to identify
Recovery Factors for PBR in Wade et al. (1998), but where values less
than 0.1 were investigated (P. Wade, pers. comm.), we predict that
where the mortality from a specified activity does not exceed Nmin *
\1/2\ Rmax * 0.013, the contemplated mortality for the specific
activity will not delay the time to recovery by more than 1 percent.
For this stock of humpback whales, Nmin * \1/2\ Rmax * 0.013 = 1.45 and
the annual mortality proposed for authorization is 0.29 (i.e., less
than 1.45), which means that the mortality proposed to be authorized in
this rule for NWTT activities would not delay the time to recovery by
more than 1 percent.
NMFS must also ensure that impacts by the applicant on the species
or stock from other types of take (i.e., harassment) do not combine
with the impacts from M/SI to adversely affect the species or stock via
impacts on annual rates of recruitment or survival, which is discussed
further below in the species- and stock-specific section.
In November 2019, NMFS published 2019 draft SARs in which PBR is
reported as 33.4 with the predicted average annual mortality greater
than or equal to 42.1 (including 22 estimated from vessel collisions
and greater than 17.3 observed fisheries interactions). While the
observed M/SI from vessel strikes remains low at 2.2 per year, the 2018
final and 2019 draft SARs rely on a new method to estimate annual
deaths by ship strike utilizing an encounter theory model that combined
species distribution models of whale density, vessel traffic
characteristics, and whale movement patterns obtained from satellite-
tagged animals in the region to estimate encounters that would result
in mortality (Rockwood et al., 2017). The model predicts 22 annual
mortalities of humpback whales from this stock from vessel strikes. The
authors (Rockwood et al., 2017) do not suggest that ship strikes
suddenly increased to 22. In fact, the model is not specific to a year,
but rather offers a generalized prediction of ship strikes off the U.S.
West Coast. Therefore, if the Rockwood et al. (2017) model is an
accurate representation of vessel strike, then similar levels of ship
strike have been occurring in past years as well. Put another way, if
the model is correct, for some number of years total human-caused
mortality has been significantly underestimated, and PBR has been
similarly exceeded by a notable amount, and yet the CA/OR/WA stock of
humpback whales is considered stable (or increasing based on population
trends since 1990) nevertheless.
The CA/OR/WA stock of humpback whales experienced a steady increase
from the 1990s through approximately 2008, and more recent estimates
through 2014 indicate a leveling off of the population size. This stock
is comprised of the feeding groups of three DPSs. Two DPSs associated
with this stock are listed under the ESA as either endangered (Central
America DPS) or threatened (Mexico DPS), while the third (Hawaii DPS)
is not listed. Humpback whales from the Hawaii DPS are anticipated to
be rare in the Study Area with a probability of the DPS foraging in the
waters of the Study Area of 1.6 percent (including summer areas of
Oregon/California and Southern British Columbia/Washington from Wade,
2017). Humpback whales from the Mexico DPS and Central America DPS are
anticipated to be more prevalent in the Study Area with probabilities
of the DPSs foraging in the waters of the Study Area of 31.7 and 100
percent, respectively (including summer

[[Page 34018]]

areas of Oregon/California and Southern British Columbia/Washington
from Wade, 2017).
As discussed earlier, we also take into consideration management
measures in place to address M/SI caused by other activities. The
California swordfish and thresher shark drift gillnet fishery is one of
the primary causes of M/SI take from fisheries interactions for
humpback whales on the West Coast. NMFS established the Pacific
Offshore Cetacean Take Reduction Team in 1996 and prepared an
associated Plan (POCTRP) to reduce the risk of M/SI via fisheries
interactions. In 1997, NMFS published final regulations formalizing the
requirements of the PCTRP, including the use of pingers following
several specific provisions and the employment of Skipper education
workshops.
Commercial fisheries such as crab pot, gillnet, and prawn fisheries
are also a significant source of mortality and serious injury for
humpback whales and other large whales and, unfortunately, have
increased mortalities and serious injuries over recent years (Carretta
et al., 2019). However, the 2019 draft SAR notes that a recent increase
in disentanglement efforts has resulted in an increase in the fraction
of cases that are reported as non-serious injuries as a result of
successful disentanglement. More importantly, since 2015, NMFS has
engaged in a multi-stakeholder process in California (including
California State resource managers, fishermen, non-governmental
organizations (NGOs), and scientists) to identify and develop solutions
and make recommendations to regulators and the fishing industry for
reducing whale entanglements (see https://www.opc.ca.gov/whale-entanglement-working-group/), referred to as the Whale Entanglement
Working Group. The Whale Entanglement Working Group has made
significant progress since 2015 and is tackling the problem from
multiple angles, including:
Development of Fact Sheets and Best Practices for specific
Fisheries issues (e.g., California Dungeness Crab Fishing BMPs and the
2018-2019 Best Fishing Practices Guide);
2018-2019 Risk Assessment and Mitigation Program (RAMP) to
support the state of California in working collaboratively with experts
(fishermen, researchers, NGOs, etc.) to identify and assess elevated
levels of entanglement risk and determine the need for management
options to reduce risk of entanglement; and
Support of pilot studies to test new fisheries
technologies to reduce take (e.g., Exploring Ropeless Fishing
Technologies for the California Dungeness Crab Fishery).
The Working Group meets regularly, posts reports and annual
recommendations, and makes all of their products and guidance documents
readily accessible for the public. The March 2019 Working Group Report
reported on the status of the fishery closure, progress and continued
development of the RAMP (though there is a separate RAMP report),
discussed the role of the Working Group (development of a new Charter),
and indicated next steps.
Importantly, in early 2019, as a result of a litigation settlement
agreement, the California Department of Fish and Wildlife (CDFW) closed
the Dungeness crab fishery three months early for the year, which is
expected to reduce the number of likely entanglements. The agreement
also limits the fishery duration over the next couple of years and has
different triggers to reduce or close it further. Further, pursuant to
the settlement, CDFW is required to apply for a Section 10 Incidental
Take Permit under the ESA to address protected species interactions
with fishing gear and crab fishing gear (pots), and they have agreed to
prepare a Conservation Plan by May 2020. Any request for such a permit
must include a Conservation Plan that specifies, among other things,
what steps the applicant will take to minimize and mitigate the
impacts, and the funding that will be available to implement such
steps.
Regarding measures in place to reduce mortality from other sources,
the Channel Islands NMS staff coordinates, collects, and monitors whale
sightings in and around a Whale Advisory Zone and the Channel Islands
NMS region, which is within the area of highest vessel strike mortality
(90th percentile) for humpback whales on the U.S. West Coast (Rockwood
et al., 2017). The seasonally established Whale Advisory Zone spans
from Point Arguello to Dana Point, including the Traffic Separation
Schemes in the Santa Barbara Channel and San Pedro Channel. Vessels
transiting the area from June through November are recommended to
exercise caution and voluntarily reduce speed to 10 kn or less for
blue, humpback, and fin whales. Channel Island NMS observers collect
information from aerial surveys conducted by NOAA, the U.S. Coast
Guard, California Department of Fish and Game, and Navy chartered
aircraft. Information on seasonal presence, movement, and general
distribution patterns of large whales is shared with mariners, NMFS'
Office of Protected Resources, the U.S. Coast Guard, the California
Department of Fish and Game, the Santa Barbara Museum of Natural
History, the Marine Exchange of Southern California, and whale
scientists. Real time and historical whale observation data collected
from multiple sources can be viewed on the Point Blue Whale Database.
More recently, similar efforts to reduce entanglement risk and
severity have also been initiated in Oregon and Washington. Both Oregon
and Washington are developing applications for ESA Incidental Take
Permits for their commercial crab fisheries. They advocate similar best
practices for their fishermen as California, and they are taking
regulatory steps related to gear marking and pot limits.
In this case, 0.29 M/SI annually means the potential for two
mortalities in one or two of the seven years and zero mortalities in
five or six of those seven years. Therefore, the Navy would not be
contributing to the total human-caused mortality at all in at least
five of the seven, or 71.4 percent, of the years covered by this rule.
That means that even if a humpback whale from the CA/OR/WA stock were
to be struck, in at least five of the seven years there could be no
effect on annual rates of recruitment or survival from Navy-caused M/
SI. Additionally, the loss of a male would have far less, if any, of an
effect on population rates than the loss of a reproductive female (as
males are known to mate with multiple females), and absent any
information suggesting that one sex is more likely to be struck than
another, we can reasonably assume that there is a 50 percent chance
that the strikes proposed to be authorized by this rule would be males,
thereby further decreasing the likelihood of impacts on the population
rate. In situations like this where potential M/SI is fractional,
consideration must be given to the lessened impacts anticipated due to
the absence of any M/SI in five or six of the years and due to the fact
that strikes could be males. Lastly, we reiterate that PBR is a
conservative metric and also not sufficiently precise to serve as an
absolute predictor of population effects upon which mortality caps
would appropriately be based. Wade et al. (1998), authors of the paper
from which the current PBR equation is derived, note that ``Estimating
incidental mortality in one year to be greater than the PBR calculated
from a single abundance survey does not prove the mortality will lead
to depletion; it identifies a population worthy of careful future
monitoring and possibly indicates that mortality-mitigation efforts
should be initiated.''

[[Page 34019]]

The information included here illustrates that this humpback whale
stock is stable, the potential (and proposed authorized) mortality is
well below 10 percent (0.87 percent) of PBR, and management actions are
in place to minimize both fisheries interactions and ship strike from
other vessel activity in one of the highest-risk areas for strikes.
More specifically, although the total human-mortality exceeds PBR, the
authorized mortality proposed for the Navy's specified activities would
incrementally contribute less than 1 percent of that and, further,
given the fact that it would occur in only one or two of the seven
years with a 50 percent chance of the take involving males (far less
impactful to the population), the potential impacts on population rates
are even less. Based on all of the considerations described above,
including consideration of the fact that the M/SI of 0.29 proposed for
authorization would not delay the time to recovery by more than 1
percent, we do not expect the potential lethal take from Navy
activities, alone, to adversely affect the CA/OR/WA stock of humpback
whales through effects on annual rates of recruitment or survival.
Nonetheless, the fact that total human-caused mortality exceeds PBR
necessitates close attention to the remainder of the impacts (i.e.,
harassment) on the CA/OR/WA stock of humpback whales from the Navy's
activities to ensure that the total authorized takes would have a
negligible impact on the species and stock. Therefore, this information
will be considered in combination with our assessment of the impacts of
authorized harassment takes in the Group and Species-Specific Analyses
section that follows.

Group and Species-Specific Analyses

The maximum amount and type of incidental take of marine mammals
reasonably likely to occur and therefore proposed to be authorized from
exposures to sonar and other active acoustic sources and explosions
during the seven-year training and testing period are shown in Tables
32 and 33 along with the discussion in the Estimated Take of Marine
Mammals section on Vessel Strike. The vast majority of predicted
exposures (greater than 99 percent) are expected to be Level B
harassment (non-injurious TTS and behavioral reactions) from acoustic
and explosive sources during training and testing activities at
relatively low received levels.
In the discussions below, the estimated Level B harassment takes
represent instances of take, not the number of individuals taken (the
much lower and less frequent Level A harassment takes are far more
likely to be associated with separate individuals), and in some cases
individuals may be taken more than one time. Below, we compare the
total take numbers (including PTS, TTS, and behavioral disruption) for
species or stocks to their associated abundance estimates to evaluate
the magnitude of impacts across the species and to individuals.
Specifically, when an abundance percentage comparison is below 100, it
means that that percentage or less of the individuals will be affected
(i.e., some individuals will not be taken at all), that the average for
those taken is one day per year, and that we would not expect any
individuals to be taken more than a few times in a year. When it is
more than 100 percent, it means there will definitely be some number of
repeated takes of individuals. For example, if the percentage is 300,
the average would be each individual is taken on three days in a year
if all were taken, but it is more likely that some number of
individuals will be taken more than three times and some number of
individuals fewer or not at all. While it is not possible to know the
maximum number of days across which individuals of a stock might be
taken, in acknowledgement of the fact that it is more than the average,
for the purposes of this analysis, we assume a number approaching twice
the average. For example, if the percentage of take compared to the
abundance is 800, we estimate that some individuals might be taken as
many as 16 times. Those comparisons are included in the sections below.
To assist in understanding what this analysis means, we clarify a
few issues related to estimated takes and the analysis here. An
individual that incurs a PTS or TTS take may sometimes, for example,
also be subject to behavioral disturbance at the same time. As
described above in this section, the degree of PTS, and the degree and
duration of TTS, expected to be incurred from the Navy's activities are
not expected to impact marine mammals such that their reproduction or
survival could be affected. Similarly, data do not suggest that a
single instance in which an animal accrues PTS or TTS and is also
subjected to behavioral disturbance would result in impacts to
reproduction or survival. Alternately, we recognize that if an
individual is subjected to behavioral disturbance repeatedly for a
longer duration and on consecutive days, effects could accrue to the
point that reproductive success is jeopardized, although those sorts of
impacts are generally not expected to result from these activities.
Accordingly, in analyzing the number of takes and the likelihood of
repeated and sequential takes, we consider the total takes, not just
the Level B harassment takes by behavioral disruption, so that
individuals potentially exposed to both threshold shift and behavioral
disruption are appropriately considered. The number of Level A
harassment takes by PTS are so low (and zero in most cases) compared to
abundance numbers that it is considered highly unlikely that any
individual would be taken at those levels more than once.
Use of sonar and other transducers would typically be transient and
temporary. The majority of acoustic effects to marine mammals from
sonar and other active sound sources during testing and training
activities would be primarily from ASW events. It is important to note
that unlike other Navy Training and Testing Study Areas, there are no
MTEs proposed for the NWTT Study Area. On the less severe end, exposure
to comparatively lower levels of sound at a detectably greater distance
from the animal, for a few or several minutes, could result in a
behavioral response such as avoiding an area that an animal would
otherwise have moved through or fed in, or breaking off one or a few
feeding bouts. More severe behavioral effects could occur when an
animal gets close enough to the source to receive a comparatively
higher level of sound, is exposed continuously to one source for a
longer time, or is exposed intermittently to different sources
throughout a day. Such effects might result in an animal having a more
severe flight response and leaving a larger area for a day or more, or
potentially losing feeding opportunities for a day. However, such
severe behavioral effects are expected to occur infrequently.
Occasional, milder behavioral reactions are unlikely to cause long-
term consequences for individual animals or populations, and even if
some smaller subset of the takes are in the form of a longer (several
hours or a day) and more severe response, if they are not expected to
be repeated over sequential days, impacts to individual fitness are not
anticipated. Nearly all studies and experts agree that infrequent
exposures of a single day or less are unlikely to impact an
individual's overall energy budget (Farmer et al., 2018; Harris et al.,
2017; King et al., 2015; NAS 2017; New et al., 2014; Southall et al.,
2007; Villegas-Amtmann et al., 2015). When impacts to individuals
increase in magnitude or severity such that either

[[Page 34020]]

repeated and sequential higher severity impacts occur (the probability
of this goes up for an individual the higher total number of takes it
has) or the total number of moderate to more severe impacts increases
substantially, especially if occurring across sequential days, then it
becomes more likely that the aggregate effects could potentially
interfere with feeding enough to reduce energy budgets in a manner that
could impact reproductive success via longer cow-calf intervals,
terminated pregnancies, or calf mortality. It is important to note that
these impacts only accrue to females, which only comprise a portion of
the population (typically approximately 50 percent). Based on energetic
models, it takes energetic impacts of a significantly greater magnitude
to cause the death of an adult marine mammal, and females will always
terminate a pregnancy or stop lactating before allowing their health to
deteriorate. Also, as noted previously, the death of an adult female
has significantly more impact on population growth rates than
reductions in reproductive success, while the death of an adult male
has very little effect on population growth rates. However, as
explained earlier, such severe impacts from the Navy's activities would
be very infrequent and not likely to occur at all for most species and
stocks. Even for those species or stocks where it is possible for a
small number of females to experience reproductive effects, we explain
below why there still would be no effect on rates of recruitment or
survival.
The analyses below in some cases address species collectively if
they occupy the same functional hearing group (i.e., low, mid, and
high-frequency cetaceans), share similar life history strategies, and/
or are known to behaviorally respond similarly to acoustic stressors.
Because some of these groups or species share characteristics that
inform the impact analysis similarly, it would be duplicative to repeat
the same analysis for each species. In addition, similar species
typically have the same hearing capabilities and behaviorally respond
in the same manner.
Thus, our analysis below considers the effects of the Navy's
activities on each affected species or stock even where discussion is
organized by functional hearing group and/or information is evaluated
at the group level. Where there are meaningful differences between a
species or stock that would further differentiate the analysis, they
are either described within the section or the discussion for those
species or stocks is included as a separate subsection. Specifically
below, we first give broad descriptions of the mysticete, odontocete,
and pinniped groups and then differentiate into further groups as
appropriate.
Mysticetes
This section builds on the broader discussion above and brings
together the discussion of the different types and amounts of take that
different species and stocks could potentially or would likely incur,
the applicable mitigation, and the status of the species and stocks to
support the preliminary negligible impact determinations for each
species or stock. We have described (earlier in this section) the
unlikelihood of any masking having effects that would impact the
reproduction or survival of any of the individual marine mammals
affected by the Navy's activities. We have also described above in the
Potential Effects of Specified Activities on Marine Mammals and their
Habitat section the unlikelihood of any habitat impacts having effects
that would impact the reproduction or survival of any of the individual
marine mammals affected by the Navy's activities. For mysticetes, there
is no predicted PTS from sonar or explosives and no predicted tissue
damage from explosives for any species. Much of the discussion below
focuses on the behavioral effects and the mitigation measures that
reduce the probability or severity of effects. Because there are
species-specific and stock-specific considerations as well as M/SI take
proposed for several stocks, at the end of the section we break out our
findings on a species-specific and, for one species, stock-specific
basis.
In Table 52 below for mysticetes, we indicate for each species and
stock the total annual numbers of take by mortality, Level A and Level
B harassment, and a number indicating the instances of total take as a
percentage of abundance.

[[Page 34021]]

[GRAPHIC] [TIFF OMITTED] TP02JN20.008

The majority of takes by harassment of mysticetes in the NWTT Study
Area are caused by anti-submarine warfare (ASW) activities in the
Offshore portion of the Study Area. Anti-submarine activities include
sources from the MFAS bin (which includes hull-mounted sonar) because
they are high level, narrowband sources in the 1-10 kHz range, which
intersect what is estimated to be the most sensitive area of hearing
for mysticetes. They also are used in a large portion of exercises (see
Tables 3 and 4). Most of the takes (90 percent) from the MF1 bin in the
NWTT Study Area would result from received levels between 160 and 178
dB SPL, while another 9 percent would result from exposure between 178
and 184 dB SPL. For the remaining active sonar bin types, the
percentages are as follows: LF4 = 97 percent between 124 and 142 dB
SPL, MF4 = 95 percent between 136 and 148 dB SPL, MF5 = 97 percent
between 112 and 142 dB SPL, and HF4 = 91 percent between 100 and 154 dB
SPL. For mysticetes, explosive training activities do not result in any
take. Explosive testing activities result in a small number of
behavioral Level B harassment takes (0-6 per stock) and TTS takes (0-2
per stock). Based on this information, the majority of the Level B
behavioral harassment is expected to be of low to sometimes moderate
severity and of a relatively shorter duration. No PTS or tissue damage
from training and testing activities is anticipated or proposed for
authorization for any species or stock.
Research and observations show that if mysticetes are exposed to
sonar or other active acoustic sources they may react in a number of
ways depending on the characteristics of the sound source, their
experience with the sound source, and whether they are migrating or on
seasonal feeding or breeding grounds. Behavioral reactions may include
alerting, breaking off feeding dives and surfacing, diving or swimming
away, or no response at all (DOD, 2017; Nowacek, 2007; Richardson,
1995; Southall et al., 2007). Overall, mysticetes have been observed to
be more reactive to acoustic disturbance when a noise source is located
directly on their migration route. Mysticetes disturbed while migrating
could pause their migration or route around the disturbance, while
males en route to breeding grounds have been shown to be less
responsive to disturbances. Although some may pause temporarily, they
will resume migration shortly after the exposure ends. Animals
disturbed while engaged in other activities such as feeding or
reproductive behaviors may be more likely to ignore or tolerate the
disturbance and continue their natural behavior patterns. Alternately,
adult females with calves may be more responsive to stressors. As noted
in the Potential Effects of Specified Activities on Marine Mammals and
Their Habitat section, there are multiple examples from behavioral
response studies of odontocetes ceasing their feeding dives when
exposed to sonar pulses at certain levels, but alternately, blue whales
were less likely to show a visible response to sonar exposures at
certain levels when feeding than when traveling. However, Goldbogen et
al. (2013) indicated some

[[Page 34022]]

horizontal displacement of deep foraging blue whales in response to
simulated MFAS. Southall et al. (2019b) observed that after exposure to
simulated and operational mid-frequency active sonar, more than 50
percent of blue whales in deep-diving states responded to the sonar,
while no behavioral response was observed in shallow-feeding blue
whales. Southall et al. (2019b) noted that the behavioral responses
they observed were generally brief, of low to moderate severity, and
highly dependent on exposure context (behavioral state, source-to-whale
horizontal range, and prey availability). Most Level B behavioral
harassment of mysticetes is likely to be short-term and of low to
sometimes moderate severity, with no anticipated effect on reproduction
or survival.
Richardson et al. (1995) noted that avoidance (temporary
displacement of an individual from an area) reactions are the most
obvious manifestations of disturbance in marine mammals. Avoidance is
qualitatively different from the startle or flight response, but also
differs in the magnitude of the response (i.e., directed movement, rate
of travel, etc.). Oftentimes avoidance is temporary, and animals return
to the area once the noise has ceased. Some mysticetes may avoid larger
activities as they move through an area, although the Navy's activities
do not typically use the same training locations day-after-day during
multi-day activities, except periodically in instrumented ranges.
Therefore, displaced animals could return quickly after even a large
activity is completed. In the ocean, the use of Navy sonar and other
active acoustic sources is transient and is unlikely to expose the same
population of animals repeatedly over a short period of time,
especially given the broader-scale movements of mysticetes.
The implementation of procedural mitigation and the sightability of
mysticetes (due to their large size) further reduces the potential for
a significant behavioral reaction or a threshold shift to occur (i.e.,
shutdowns are expected to be successfully implemented), which is
reflected in the amount and type of incidental take that is anticipated
to occur and proposed for authorization.
As noted previously, when an animal incurs a threshold shift, it
occurs in the frequency from that of the source up to one octave above.
This means that the vast majority of threshold shifts caused by Navy
sonar sources will typically occur in the range of 2-20 kHz (from the
1-10 kHz MF bin, though in a specific narrow band within this range as
the sources are narrowband), and if resulting from hull-mounted sonar,
will be in the range of 3.5-7 kHz. The majority of mysticete
vocalizations occur in frequencies below 1 kHz, which means that TTS
incurred by mysticetes will not interfere with conspecific
communication. Additionally, many of the other critical sounds that
serve as cues for navigation and prey (e.g., waves, fish,
invertebrates) occur below a few kHz, which means that detection of
these signals will not be inhibited by most threshold shift either.
When we look in ocean areas where the Navy has been intensively
training and testing with sonar and other active acoustic sources for
decades, there is no data suggesting any long-term consequences to
reproduction or survival rates of mysticetes from exposure to sonar and
other active acoustic sources.
All the mysticete species discussed in this section would benefit
from the procedural mitigation measures described earlier in the
Proposed Mitigation Measures section. Additionally, the Navy would
limit activities and employ other measures in mitigation areas that
would avoid or reduce impacts to mysticetes. Where these mitigation
areas are designed to mitigate impacts to particular species or stocks
(gray whales and humpback whales), they are discussed in detail below.
Below we compile and summarize the information that supports our
preliminary determination that the Navy's activities would not
adversely affect any species or stock through effects on annual rates
of recruitment or survival for any of the affected mysticete stocks.

Blue Whale (Eastern North Pacific Stock)

Blue whales are listed as endangered under the ESA throughout their
range, but there is no ESA designated critical habitat or biologically
important areas identified for this species in the NWTT Study Area. The
SAR identifies this stock as ``stable''. We further note that this
stock was originally listed under the ESA as a result of the impacts
from commercial whaling, which is no longer affecting the species. Blue
whales are anticipated to be present in summer and winter months and
only in the Offshore Area of the Study Area. No mortality from either
explosives or vessel strike and no Level A harassment is anticipated or
proposed for authorization.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is less than 1 percent. Given the range of
blue whales, this information indicates that only a very small portion
of individuals in the stock are likely impacted and repeated exposures
of individuals are not anticipated. Regarding the severity of those
individual takes by behavioral Level B harassment, we have explained
that the duration of any exposure is expected to be between minutes and
hours (i.e., relatively short) and the received sound levels largely
below 172 dB with a small portion up to 184 dB (i.e., of a moderate or
lower level, less likely to evoke a severe response). Regarding the
severity of TTS takes, we have explained that they are expected to be
low-level, of short duration, and mostly not in a frequency band that
would be expected to interfere with blue whale communication or other
important low-frequency cues and that the associated lost opportunities
and capabilities are not at a level that would impact reproduction or
survival.
Altogether, this population is stable, only a very small portion of
the stock is anticipated to be impacted, and any individual blue whale
is likely to be disturbed at a low-moderate level. No mortality and no
Level A harassment is anticipated or proposed for authorization. The
low magnitude and severity of harassment effects is not expected to
result in impacts on the reproduction or survival of any individuals,
let alone have impacts on annual rates of recruitment or survival. For
these reasons, we have preliminarily determined, in consideration of
all of the effects of the Navy's activities combined, that the proposed
authorized take would have a negligible impact on the Eastern North
Pacific stock of blue whales.

Fin Whale (Northeast Pacific Stock and California/Oregon/Washington
Stock)

Fin whales are listed as endangered under the ESA throughout their
range, but no ESA designated critical habitat or biologically important
areas are identified for this species in the NWTT Study Area. The SAR
identifies these stocks as ``increasing.'' NMFS is proposing to
authorize two mortalities of fin whales over the seven years covered by
this rule, but because it is not possible to determine from which stock
these potential takes would occur, that is 0.29 mortality annually for
each stock. The addition of this 0.29 annual mortality still leaves the
total annual human-caused mortality well under residual PBR (37.1 for
the CA/OR/WA stock and 4.7 for the Northeast Pacific stock) and below
the insignificance threshold for both stocks. No mortality from
explosives and no Level A

[[Page 34023]]

harassment is anticipated or proposed for authorization.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is less than 1 percent for the Northeast
Pacific stock and 1.5 percent for the CA/OR/WA stock. This information
indicates that only a very small portion of individuals in each stock
are likely impacted and repeated exposures of individuals are not
anticipated. Regarding the severity of those individual Level B
harassment takes by behavioral disruption, we have explained that the
duration of any exposure is expected to be between minutes and hours
(i.e., relatively short) and the received sound levels largely below
172 dB with a small portion up to 184 dB (i.e., of a moderate or lower
level, less likely to evoke a severe response). Regarding the severity
of TTS takes, they are expected to be low-level, of short duration, and
mostly not in a frequency band that would be expected to interfere with
fin whale communication or other important low-frequency cues--and the
associated lost opportunities and capabilities are not at a level that
would impact reproduction or survival.
Altogether, these populations are increasing, only a small portion
of each stock is anticipated to be impacted, and any individual fin
whale is likely to be disturbed at a low-moderate level. No Level A
harassment is anticipated or proposed to be authorized. This low
magnitude and severity of harassment effects is not expected to result
in impacts on individual reproduction or survival for any individuals,
nor are these harassment takes combined with the proposed authorized
mortality expected to adversely affect these stocks through impacts on
annual rates of recruitment or survival. For these reasons, we have
preliminarily determined, in consideration of all of the effects of the
Navy's activities combined, that the proposed authorized take would
have a negligible impact on both the Northeast Pacific and CA/OR/WA
stocks of fin whales.

Humpback Whale (Central North Pacific Stock)

The Central North Pacific stock of humpback whales consists of
winter/spring humpback whale populations of the Hawaiian Islands which
migrate primarily to foraging habitat in northern British Columbia/
Southeast Alaska, the Gulf of Alaska, and the Bering Sea/Aleutian
Islands (Muto et al. 2019). Three Feeding Area biologically important
areas for humpback whales overlap with the NWTT Study Area: Northern
Washington Feeding Area for humpback whales (May-November); Stonewall
and Heceta Bank Feeding Area for humpback whales (May-November); and
Point St. George Feeding Area for humpback whales (July-November)
(Calambokidis et al., 2015). The Marine Species Coastal, Olympic Coast
National Marine Sanctuary, Stonewall and Hecta Bank Humpback Whale, and
Point St. George Humpback Whale Mitigation Areas overlap with these
important foraging areas. The mitigation measures implemented in each
of these areas including no MF1 MFAS use seasonally or limited MFAS use
year round, no explosive training, etc. (see details for each area in
the Proposed Mitigation section), would reduce the severity of impacts
to humpback whales by reducing interference in feeding that could
result in lost feeding opportunities or necessitate additional energy
expenditure to find other good opportunities.
The SAR identifies this stock as ``increasing'' and the associated
Hawaii DPS is not listed under the ESA. No mortality from explosives
and no Level A harassment is anticipated or proposed for authorization.
NMFS proposes to authorize two mortalities of humpback whales over the
seven years covered by this rule, but because it is not possible to
determine from which stock these potential takes would occur, that is
0.29 mortality annually for both this stock and the CA/OR/WA stock
(discussed separately below). The addition of this 0.29 annual
mortality still leaves the total annual human-caused mortality well
under both the insignificance threshold and residual PBR (57.6).
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated instances of take
compared to the abundance is 1 percent. This information and the
complicated far-ranging nature of the stock structure indicates that
only a very small portion of the stock is likely impacted and repeated
exposures of individuals are not anticipated. Regarding the severity of
those individual Level B harassment takes by behavioral disruption, we
have explained that the duration of any exposure is expected to be
between minutes and hours (i.e., relatively short) and the received
sound levels largely below 172 dB with a small portion up to 184 dB
(i.e., of a moderate or lower level, less likely to evoke a severe
response). Regarding the severity of TTS takes, they are expected to be
low-level, of short duration, and mostly not in a frequency band that
would be expected to interfere with humpback whale communication or
other important low-frequency cues, and that the associated lost
opportunities and capabilities are not at a level that would impact
reproduction or survival.
Altogether, this population is increasing and the associated DPS is
not listed as endangered or threatened under the ESA. Only a very small
portion of the stock is anticipated to be impacted and any individual
humpback whale is likely to be disturbed at a low-moderate level. No
Level A harassment is anticipated or proposed to be authorized. This
low magnitude and severity of harassment effects is not expected to
result in impacts on individual reproduction or survival, nor are these
harassment takes combined with the proposed authorized mortality
expected to adversely affect this stock through effects on annual rates
of recruitment or survival. For these reasons, we have preliminarily
determined, in consideration of all of the effects of the Navy's
activities combined, that the proposed authorized take would have a
negligible impact on the Central North Pacific stock of humpback
whales.

Humpback Whale (California/Oregon/Washington Stock)

The CA/OR/WA stock of humpback whales includes individuals from
three ESA DPSs: Central America (endangered), Mexico (threatened), and
Hawaii (not listed). There is no ESA-designated critical habitat for
humpback whales, however NMFS recently proposed to designate critical
habitat for humpback whales (84 FR 54354; October 9, 2019). Three
Feeding Area biologically important areas for humpback whales overlap
with the NWTT Study Area: Northern Washington Feeding Area for humpback
whales (May-November); Stonewall and Heceta Bank Feeding Area for
humpback whales (May-November); and Point St. George Feeding Area for
humpback whales (July-November) (Calambokidis et al., 2015). The Marine
Species Coastal, Olympic Coast National Marine Sanctuary, Stonewall and
Hecta Bank Humpback Whale, and Point St. George Humpback Whale
Mitigation Areas overlap with these important foraging areas. The
mitigation measures implemented in each of these areas including no MF1
MFAS use seasonally or limited MFAS use year round, no explosive
training, etc. (see details for each area in the Proposed Mitigation
section), would reduce the severity of impacts to humpback whales by
reducing interference in feeding that could result in lost feeding

[[Page 34024]]

opportunities or necessitate additional energy expenditure to find
other good opportunities.
The SAR identifies this stock as stable (having shown a long-term
increase from 1990 and then leveling off between 2008 and 2014). NMFS
proposes to authorize two mortalities over the seven years covered by
this rule, or 0.29 mortality annually. With the addition of this 0.29
annual mortality, the total annual human-caused mortality exceeds
residual PBR by 9.19. However, as described in more detail in the
Serious Injury or Mortality section, when total human-caused mortality
exceeds PBR, we consider whether the incremental addition of a small
amount of mortality proposed for authorization from the specified
activity may still result in a negligible impact, in part by
identifying whether it is less than 10 percent of PBR. In this case,
the mortality proposed for authorization is well below 10 percent of
PBR (less than one percent, in fact) and management measures are in
place to reduce mortality from other sources. More importantly, as
described above in the Serious Injury or Mortality section, the
mortality of 0.29 proposed for authorization would not delay the time
to recovery by more than 1 percent. Given these considerations, the
incremental addition of two mortalities over the course of the seven-
year Navy rule is not expected to, alone, lead to adverse impacts on
the stock through effects on annual rates of recruitment or survival.
No mortality from explosives and no Level A harassment is anticipated
or proposed for authorization.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is 3 percent. Given the range of humpback
whales, this information indicates that only a very small portion of
individuals in the stock are likely impacted and repeated exposures of
individuals are not anticipated. Regarding the severity of those
individual Level B harassment takes by behavioral disruption, we have
explained that the duration of any exposure is expected to be between
minutes and hours (i.e., relatively short) and the received sound
levels largely below 172 dB with a small portion up to 184 dB (i.e., of
a moderate or lower level, less likely to evoke a severe response).
Regarding the severity of TTS takes, they are expected to be low-level,
of short duration, and mostly not in a frequency band that would be
expected to interfere with humpback whale communication or other
important low-frequency cues and the associated lost opportunities and
capabilities are not at a level that would impact reproduction or
survival.
Altogether, this population is stable (even though two of the three
associated DPSs are listed as endangered or threatened under the ESA),
only a small portion of the stock is anticipated to be impacted, and
any individual humpback whale is likely to be disturbed at a low-
moderate level. No Level A harassment is anticipated or proposed to be
authorized. This low magnitude and severity of harassment effects is
not expected to result in impacts on the reproduction or survival of
any individuals and, therefore, when combined with the proposed
authorized mortality (which our earlier analysis indicated will not,
alone, have more than a negligible impact on this stock of humpback
whales), the total take is not expected to adversely affect this stock
through impacts on annual rates of recruitment or survival. For these
reasons, we have preliminarily determined, in consideration of all of
the effects of the Navy's activities combined, that the proposed
authorized take would have a negligible impact on the CA/OR/WA stock of
humpback whales.

Minke Whale (Alaska and California/Oregon/Washington Stocks)

The status of these stocks is unknown and the species is not listed
under the ESA. No biologically important areas have been identified for
this species in the NWTT Study Area. NMFS proposes to authorize one
mortality over the seven years covered by this rule, or 0.14 mortality
annually. The addition of this 0.14 annual mortality still leaves the
total annual human-caused mortality well under the residual PBR (2.2)
and below the insignificance threshold. No mortality from explosives
and no Level A harassment is anticipated or proposed for authorization.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is less than 1 percent for the Alaska stock
(based on, to be conservative, the smallest available provisional
estimate in the SAR, which is derived from surveys that cover only a
portion of the stock's range) and 47.5 percent for the CA/OR/WA stock.
Given the range of minke whales, this information indicates that only a
portion of individuals in these stocks are likely to be impacted and
repeated exposures of individuals are not anticipated. Regarding the
severity of those individual Level B harassment takes by behavioral
disruption, we have explained that the duration of any exposure is
expected to be between minutes and hours (i.e., relatively short) and
the received sound levels largely below 172 dB with a small portion up
to 184 dB (i.e., of a moderate or lower level, less likely to evoke a
severe response). Regarding the severity of TTS takes, they are
expected to be low-level, of short duration, and mostly not in a
frequency band that would be expected to interfere with minke whale
communication or other important low-frequency cues--and the associated
lost opportunities and capabilities are not at a level that would
impact reproduction or survival.
Altogether, although the status of the stocks is unknown, the
species is not listed under the ESA as endangered or threatened, only a
portion of these stocks is anticipated to be impacted, and any
individual minke whale is likely to be disturbed at a low-moderate
level. No Level A harassment is anticipated or proposed to be
authorized. This low magnitude and severity of harassment effects is
not expected to result in impacts on individual reproduction or
survival, nor are these harassment takes combined with the proposed
authorized mortality expected to adversely affect these stocks through
effects on annual rates of recruitment or survival. For these reasons,
we have preliminarily determined, in consideration of all of the
effects of the Navy's activities combined, that the proposed authorized
take would have a negligible impact on the Alaska and CA/OR/WA stocks
of minke whales.

Sei Whale (Eastern North Pacific Stock)

The status of this stock is unknown, however sei whales are listed
as endangered under the ESA throughout their range. There is no ESA
designated critical habitat or biologically important areas identified
for this species in the NWTT Study Area. No mortality from either
explosives or vessel strikes and no Level A harassment is anticipated
or proposed for authorization.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is 16 percent. This information and the large
range of sei whales suggests that only a small portion of individuals
in the stock are likely impacted and repeated exposures of individuals
are not anticipated. Regarding the severity of those individual Level B
harassment takes by behavioral disruption, we have explained that the
duration of any exposure is expected to be between

[[Page 34025]]

minutes and hours (i.e., relatively short) and the received sound
levels largely below 172 dB with a small portion up to 184 dB (i.e., of
a moderate or lower level, less likely to evoke a severe response).
Regarding the severity of TTS takes, they are expected to be low-level,
of short duration, and mostly not in a frequency band that would be
expected to interfere with sei whale communication or other important
low-frequency cues and the associated lost opportunities and
capabilities are not at a level that would impact reproduction or
survival.
Altogether, the status of the stock is unknown and the species is
listed as endangered, but only a small portion of the stock is
anticipated to be impacted and any individual sei whale is likely to be
disturbed at a low-moderate level. No mortality and no Level A
harassment is anticipated or proposed for authorization. This low
magnitude and severity of harassment effects is not expected to result
in impacts on individual reproduction or survival, much less annual
rates of recruitment or survival. For these reasons, we have
preliminarily determined, in consideration of all of the effects of the
Navy's activities combined, that the proposed authorized take would
have a negligible impact on the Eastern North Pacific stock of sei
whales.

Gray Whale (Eastern North Pacific Stock)

The SAR identifies this stock as ``increasing'' and the associated
DPS is not listed under the ESA. The NWTT Study Area overlaps with the
offshore Northwest Washington and the Northern Puget Sound gray whale
Feeding biologically important areas, and a portion of the Northwest
coast of Washington approximately from Pacific Beach (WA) and extending
north to the Strait of Juan de Fuca overlaps with the gray whale
Migrations Corridor biologically important area. The Marine Species
Coastal, Olympic Coast National Marine Sanctuary, Stonewall and Hecta
Bank Humpback Whale, and Point St. George Humpback Whale, and Northern
Puget Sound Gray Whale Mitigation Areas overlap with these important
foraging and migration areas. The mitigation measures implemented in
each of these areas including no MF1 MFAS use seasonally or limited
MFAS use year round, no explosive training, etc. (see details for each
area in the Proposed Mitigation section), would reduce the severity of
impacts to gray whales by reducing interference in feeding and
migration that could result in lost feeding opportunities or
necessitate additional energy expenditure to find other good foraging
opportunities or move migration routes.
NMFS proposes to authorize one mortality over the seven years
covered by this rule, or 0.14 mortality annually. The addition of this
0.14 annual mortality still leaves the total annual human-caused
mortality well under both the insignificance threshold and residual PBR
(661.6). No mortality from explosives and no Level A harassment is
anticipated or proposed for authorization.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is less than 1 percent. This information
indicates that only a very small portion of individuals in the stock
are likely to be impacted and repeated exposures of individuals are not
anticipated. Regarding the severity of those individual Level B
harassment takes by behavioral disruption, we have explained that the
duration of any exposure is expected to be between minutes and hours
(i.e., relatively short) and the received sound levels largely below
172 dB with a small portion up to 184 dB (i.e., of a moderate or lower
level, less likely to evoke a severe response). Regarding the severity
of TTS takes, they are expected to be low-level, of short duration, and
mostly not in a frequency band that would be expected to interfere with
gray whale communication or other important low-frequency cues and that
the associated lost opportunities and capabilities are not at a level
that would impact reproduction or survival.
Altogether, while we have considered the impacts of the gray whale
UME, this population of gray whales is not endangered or threatened
under the ESA and the stock is increasing. No Level A harassment is
anticipated or proposed to be authorized. Only a very small portion of
the stock is anticipated to be impacted by Level B harassment and any
individual gray whale is likely to be disturbed at a low-moderate
level. This low magnitude and severity of harassment effects is not
expected to result in impacts to reproduction or survival for any
individuals, nor are these harassment takes combined with the proposed
authorized mortality of one whale over the seven-year period expected
to adversely affect this stock through impacts on annual rates of
recruitment or survival. For these reasons, we have preliminarily
determined, in consideration of all of the effects of the Navy's
activities combined, that the proposed authorized take would have a
negligible impact on the Eastern North Pacific stock of gray whales.
Odontocetes
This section builds on the broader discussion above and brings
together the discussion of the different types and amounts of take that
different species and stocks could potentially or would likely incur,
the applicable mitigation, and the status of the species and stock to
support the negligible impact determinations for each species or stock.
We have described (earlier in this section) the unlikelihood of any
masking having effects that would impact the reproduction or survival
of any of the individual marine mammals affected by the Navy's
activities. We have also described above in the Potential Effects of
Specified Activities on Marine Mammals and their Habitat section the
unlikelihood of any habitat impacts having effects that would impact
the reproduction or survival of any of the individual marine mammals
affected by the Navy's activities. For odontocetes, there is no
anticipated M/SI or tissue damage from sonar or explosives for any
species. Here, we include information that applies to all of the
odontocete species, which are then further divided and discussed in
more detail in the following subsections: Sperm whales, dwarf sperm
whales, and pygmy sperm whales; beaked whales; dolphins and small
whales; and porpoises. These subsections include more specific
information about the groups, as well as conclusions for each species
or stock represented.
The majority of takes by harassment of odontocetes in the NWTT
Study Area are caused by sources from the MFAS bin (which includes
hull-mounted sonar) because they are high level, typically narrowband
sources at a frequency (in the 1-10 kHz range) that overlaps a more
sensitive portion (though not the most sensitive) of the MF hearing
range and they are used in a large portion of exercises (see Tables 3
and 4). For odontocetes other than beaked whales and porpoises (for
which these percentages are indicated separately in those sections),
most of the takes (96 percent) from the MF1 bin in the NWTT Study Area
would result from received levels between 160 and 172 dB SPL. For the
remaining active sonar bin types, the percentages are as follows: LF4 =
99 percent between 124 and 154 dB SPL, MF4 = 99 percent between 136 and
166 dB SPL, MF5 = 98 percent between 112 and 148 dB SPL, and HF4 = 95
percent between 100 and 160 dB SPL. Based on this information, the
majority of the takes by Level B behavioral harassment are expected to

[[Page 34026]]

be low to sometimes moderate in nature, but still of a generally
shorter duration.
For all odontocetes, takes from explosives (Level B behavioral
harassment, TTS, or PTS) comprise a very small fraction (and low
number) of those caused by exposure to active sonar. For the following
odontocetes, zero takes from explosives are expected to occur: Common
bottlenose dolphins, killer whales, short-beaked common dolphins,
short-finned pilot whales, the Alaska stock of Dall's porpoises,
Southeast Alaska stock of harbor porpoises, sperm whales, Baird's
beaked whale, Cuvier's beaked whale, and Mesoplodon species. For Level
B behavioral disruption from explosives, with the exception of
porpoises, one take is anticipated for the remaining species/stocks.
For the CA/OR/WA stock of Dall's porpoise and the remaining three
harbor porpoise stocks 1-91 Level B behavioral takes from explosives
are anticipated. Similarly the instances of TTS and PTS expected to
occur from explosives for all remaining species/stocks, with the
exception of porpoises, are anticipated to be low (1-3 for TTS and 1
for PTS). Because of the lower TTS and PTS thresholds for HF
odontocetes, for the CA/OR/WA stock of Dall's porpoise and the
remaining three harbor porpoise stocks, TTS takes range from 61-214 and
PTS takes range from 27-86.
Because the majority of harassment takes of odontocetes result from
the sources in the MFAS bin, the vast majority of threshold shift would
occur at a single frequency within the 1-10 kHz range and, therefore,
the vast majority of threshold shift caused by Navy sonar sources would
be at a single frequency within the range of 2-20 kHz. The frequency
range within which any of the anticipated narrowband threshold shift
would occur would fall directly within the range of most odontocete
vocalizations (2-20 kHz). For example, the most commonly used hull-
mounted sonar has a frequency around 3.5 kHz, and any associated
threshold shift would be expected to be at around 7 kHz. However,
odontocete vocalizations typically span a much wider range than this,
and alternately, threshold shift from active sonar will often be in a
narrower band (reflecting the narrower band source that caused it),
which means that TTS incurred by odontocetes would typically only
interfere with communication within a portion of their range (if it
occurred during a time when communication with conspecifics was
occurring) and, as discussed earlier, it would only be expected to be
of a short duration and relatively small degree. Odontocete
echolocation occurs predominantly at frequencies significantly higher
than 20 kHz, though there may be some small overlap at the lower part
of their echolocating range for some species, which means that there is
little likelihood that threshold shift, either temporary or permanent,
would interfere with feeding behaviors. Many of the other critical
sounds that serve as cues for navigation and prey (e.g., waves, fish,
invertebrates) occur below a few kHz, which means that detection of
these signals will not be inhibited by most threshold shift either. The
low number of takes by threshold shift that might be incurred by
individuals exposed to explosives would likely be lower frequency (5
kHz or less) and spanning a wider frequency range, which could slightly
lower an individual's sensitivity to navigational or prey cues, or a
small portion of communication calls, for several minutes to hours (if
temporary) or permanently. There is no reason to think that any of the
individual odontocetes taken by TTS would incur these types of takes
over more than one day, or over a few days at most, and therefore they
are unlikely to incur impacts on reproduction or survival. PTS takes
from these sources are very low, and while spanning a wider frequency
band, are still expected to be of a low degree (i.e., low amount of
hearing sensitivity loss) and unlikely to affect reproduction or
survival.
The range of potential behavioral effects of sound exposure on
marine mammals generally, and odontocetes specifically, has been
discussed in detail previously. There are behavioral patterns that
differentiate the likely impacts on odontocetes as compared to
mysticetes however. First, odontocetes echolocate to find prey, which
means that they actively send out sounds to detect their prey. While
there are many strategies for hunting, one common pattern, especially
for deeper diving species, is many repeated deep dives within a bout,
and multiple bouts within a day, to find and catch prey. As discussed
above, studies demonstrate that odontocetes may cease their foraging
dives in response to sound exposure. If enough foraging interruptions
occur over multiple sequential days, and the individual either does not
take in the necessary food, or must exert significant effort to find
necessary food elsewhere, energy budget deficits can occur that could
potentially result in impacts to reproductive success, such as
increased cow/calf intervals (the time between successive calving).
Second, while many mysticetes rely on seasonal migratory patterns that
position them in a geographic location at a specific time of the year
to take advantage of ephemeral large abundances of prey (i.e.,
invertebrates or small fish, which they eat by the thousands),
odontocetes forage more homogeneously on one fish or squid at a time.
Therefore, if odontocetes are interrupted while feeding, it is often
possible to find more prey relatively nearby.

Sperm Whale, Dwarf Sperm Whale, and Pygmy Sperm Whale

This section builds on the broader odontocete discussion above and
brings together the discussion of the different types and amounts of
take that different species and stocks could potentially or would
likely incur, the applicable mitigation, and the status of the species
and stocks to support the preliminary negligible impact determinations
for each species or stock. For sperm whales, there is no predicted PTS
from sonar or explosives and no predicted tissue damage from
explosives. For dwarf sperm whales and pygmy sperm whales (described as
Kogia species below) no mortality or tissue damage from sonar or
explosives is anticipated or proposed for authorization and only one
PTS take is predicted.
In Table 53 below for sperm whales and Kogia species, we indicate
the total annual numbers of take by mortality, Level A and Level B
harassment, and a number indicating the instances of total take as a
percentage of abundance.

[[Page 34027]]

[GRAPHIC] [TIFF OMITTED] TP02JN20.009

As discussed above, the majority of Level B harassment behavioral
takes of odontocetes, and thereby sperm whales and Kogia species, is
expected to be in the form of low to occasionally moderate severity of
a generally shorter duration. As mentioned earlier in this section, we
anticipate more severe effects from takes when animals are exposed to
higher received levels or for longer durations. Occasional milder Level
B behavioral harassment, as is expected here, is unlikely to cause
long-term consequences for either individual animals or populations,
even if some smaller subset of the takes are in the form of a longer
(several hours or a day) and more moderate response.
We note that Kogia species (dwarf and pygmy sperm whales), as HF-
sensitive species, have a lower PTS threshold than all other groups and
therefore are generally likely to experience larger amounts of TTS and
PTS, and NMFS accordingly has evaluated and would authorize higher
numbers. However, Kogia whales are still likely to avoid sound levels
that would cause higher levels of TTS (greater than 20 dB) or PTS.
Therefore, even though the number of TTS takes are higher than for
other odontocetes, for all of the reasons described above, TTS and PTS
are not expected to impact reproduction or survival of any individual.
Below we compile and summarize the information that supports our
preliminary determination that the Navy's activities would not
adversely affect sperm whales and pygmy and dwarf sperm whales through
effects on annual rates of recruitment or survival.
Sperm Whale (California/Oregon/Washington Stock)
The SAR identifies the CA/OR/WA stock of sperm whales as ``stable''
and the species is listed as endangered under the ESA. No critical
habitat has been designated for sperm whales under the ESA and there
are no biologically important areas for sperm whales in the NWTT Study
Area. NMFS proposes to authorize one mortality for the CA/OR/WA stock
of sperm whales over the seven years covered by this rule, or 0.14
mortality annually. The addition of this 0.14 annual mortality still
leaves the total human-caused mortality under residual PBR (2.1) and
below the insignificance threshold. No mortality from explosives and no
Level A harassment is anticipated or proposed for authorization.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is 42 percent for sperm whales. Given the
range of this stock (which extends the entire length of the West Coast,
as well as beyond the U.S. EEZ boundary), this information indicates
that only a portion of the individuals in the stock are likely to be
impacted and repeated exposures of individuals are not anticipated.
Additionally, while interrupted feeding bouts are a known response and
concern for odontocetes, we also know that there are often viable
alternative habitat options in the relative vicinity. Regarding the
severity of those individual Level B harassment takes by behavioral
disruption, we have explained that the duration of any exposure is
expected to be between minutes and hours (i.e., relatively short) and
the received sound levels largely below 172 dB (i.e., of a lower, to
occasionally moderate, level and less likely to evoke a severe
response). Regarding the severity of TTS takes, they are expected to be
low-level, of short duration, and mostly not in a frequency band that
would be expected to interfere with sperm whale communication or other
important low-frequency cues, and that the associated lost
opportunities and capabilities are not at a level that will impact
reproduction or survival.
Altogether, this population is stable (even though the species is
listed under the ESA), only a portion of the stock is anticipated to be
impacted, and any individual sperm whale is likely to be disturbed at a
low-moderate level. No Level A harassment is anticipated or proposed to
be authorized. This low magnitude and severity of harassment effects is
not expected to result in impacts on individual reproduction or
survival for any individuals, nor are these harassment takes combined
with the proposed authorized mortality expected to adversely affect
this stock through impacts on annual rates of recruitment or survival.
For these reasons, we have preliminarily determined, in consideration
of all of the effects of the Navy's activities combined, that the
proposed authorized take would have a negligible impact on the CA/OR/WA
stock of sperm whales.
Kogia Species (California/Oregon/Washington Stocks)
The status of the CA/OR/WA stocks of pygmy and dwarf sperm whales
(Kogia

[[Page 34028]]

species) is unknown and neither are listed under the ESA. There are no
biologically important areas for Kogia in the NWTT Study Area. No
mortality or Level A harassment from tissue damage are anticipated or
proposed for authorization, and one PTS Level A harassment take is
expected and proposed for authorization. Due to their pelagic
distribution, small size, and cryptic behavior, pygmy sperm whales and
dwarf sperm whales (Kogia species) are rarely sighted during at-sea
surveys and are difficult to distinguish between when visually observed
in the field. Many of the relatively few observations of Kogia species
off the U.S. West Coast were not identified to species. All at-sea
sightings of Kogia species have been identified as pygmy sperm whales
or Kogia species generally. Stranded dwarf sperm and pygmy sperm whales
have been found on the U.S. West Coast, however dwarf sperm whale
strandings are rare. NMFS SARs suggest that the majority of Kogia
sighted off the U.S. West Coast were likely pygmy sperm whales. As
such, the stock estimate in the NMFS SAR for pygmy sperm whales is the
estimate derived for all Kogia species in the region (Barlow, 2016),
and no separate abundance estimate can be determined for dwarf sperm
whales, though some low number likely reside in the U.S. EEZ. Due to
the lack of an abundance estimate it is not possible to predict the
amount of Level A and Level B harassment take of dwarf sperm whales and
therefore take estimates are identified as Kogia whales (including both
pygmy and dwarf sperm whales). We assume only a small portion of those
takes are likely to be dwarf sperm whales as the available information
indicates that the density and abundance in the U.S. EEZ is low.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is 21 percent. Given the range of these
stocks (which extends the entire length of the West Coast, as well as
beyond the U.S. EEZ boundary), this information indicates that only a
portion of the individuals in the stocks are likely to be impacted and
repeated exposures of individuals are not anticipated. Additionally,
while interrupted feeding bouts are a known response and concern for
odontocetes, we also know that there are often viable alternative
habitat options in the relative vicinity. Regarding the severity of
those individual Level B harassment takes by behavioral disruption, we
have explained that the duration of any exposure is expected to be
between minutes and hours (i.e., relatively short) and the received
sound levels largely below 172 dB (i.e., of a lower, to occasionally
moderate, level and less likely to evoke a severe response). Regarding
the severity of TTS takes, they are expected to be low-level, of short
duration, and mostly not in a frequency band that would be expected to
interfere with sperm whale communication or other important low-
frequency cues, and that the associated lost opportunities and
capabilities are not at a level that will impact reproduction or
survival. For these same reasons (low level and frequency band), while
a small permanent loss of hearing sensitivity (PTS) may include some
degree of energetic costs for compensating or may mean some small loss
of opportunities or detection capabilities, at the expected scale the
estimated one Level A harassment take by PTS would be unlikely to
impact behaviors, opportunities, or detection capabilities to a degree
that would interfere with reproductive success or survival of the
affected individual. Thus, the one Level A harassment take by PTS for
these stocks would be unlikely to affect rates of recruitment and
survival for the stock.
Altogether, although the status of the stocks is unknown, these
species are not listed under the ESA as endangered or threatened, only
a portion of these stocks is anticipated to be impacted, and any
individual Kogia whale is likely to be disturbed at a low-moderate
level. This low magnitude and severity of harassment effects is not
expected to result in impacts on the reproduction or survival of any
individuals, let alone have impacts on annual rates of recruitment or
survival. One individual could be taken by PTS annually of likely low
severity. A small permanent loss of hearing sensitivity (PTS) may
include some degree of energetic costs for compensating or may mean
some small loss of opportunities or detection capabilities, but at the
expected scale the estimated one Level A harassment take by PTS would
be unlikely to impact behaviors, opportunities, or detection
capabilities to a degree that would interfere with reproductive success
or survival of that individual, let alone affect annual rates of
recruitment or survival. For these reasons, we have preliminarily
determined, in consideration of all of the effects of the Navy's
activities combined, that the proposed authorized take would have a
negligible impact on the CA/OR/WA stocks of Kogia whales.

Beaked Whales

This section builds on the broader odontocete discussion above and
brings together the discussion of the different types and amounts of
take that different beaked whale species and stocks would likely incur,
the applicable mitigation for stocks, and the status of the species and
stocks to support the preliminary negligible impact determinations for
each species or stock. For beaked whales, there is no anticipated Level
A harassment by PTS or tissue damage from sonar or explosives, and no
mortality is anticipated or proposed for authorization.
In Table 54 below for beaked whales, we indicate the total annual
numbers of take by mortality, Level A and Level B harassment, and a
number indicating the instances of total take as a percentage of
abundance.

[[Page 34029]]

[GRAPHIC] [TIFF OMITTED] TP02JN20.010

This first paragraph provides specific information that is in lieu
of the parallel information provided for odontocetes as a whole. The
majority of takes by harassment of beaked whales in the NWTT Study Area
are caused by sources from the MFAS bin (which includes hull-mounted
sonar) because they are high level narrowband sources that fall within
the 1-10 kHz range, which overlap a more sensitive portion (though not
the most sensitive) of the MF hearing range. Also, of the sources
expected to result in take, they are used in a large portion of
exercises (see Tables 3 and 4). Most of the takes (95 percent) from the
MF1 bin in the NWTT Study Area would result from received levels
between 142 and 160 dB SPL. For the remaining active sonar bin types,
the percentages are as follows: LF4 = 99 percent between 118 and 148 dB
SPL, MF4 = 97 percent between 124 and 148 dB SPL, MF5 = 99 percent
between 100 and 148 dB SPL, and HF4 = 97 percent between 100 and 154 dB
SPL. Given the levels they are exposed to and beaked whale sensitivity,
some responses would be of a lower severity, but many would likely be
considered moderate, but still of generally short duration.
Research has shown that beaked whales are especially sensitive to
the presence of human activity (Pirotta et al., 2012; Tyack et al.,
2011) and therefore have been assigned a lower harassment threshold,
with lower received levels resulting in a higher percentage of
individuals being harassed and a more distant distance cutoff (50 km
for high source level, 25 km for moderate source level).
Beaked whales have been documented to exhibit avoidance of human
activity or respond to vessel presence (Pirotta et al., 2012). Beaked
whales were observed to react negatively to survey vessels or low
altitude aircraft by quick diving and other avoidance maneuvers, and
none were observed to approach vessels (Wursig et al., 1998). It has
been speculated for some time that beaked whales might have unusual
sensitivities to sonar sound due to their likelihood of stranding in
conjunction with MFAS use, although few definitive causal relationships
between MFAS use and strandings have been documented (see Potential
Effects of Specified Activities on Marine Mammals and their Habitat
section).
Research and observations show that if beaked whales are exposed to
sonar or other active acoustic sources, they may startle, break off
feeding dives, and avoid the area of the sound source to levels of 157
dB re: 1 [micro]Pa, or below (McCarthy et al., 2011). Acoustic
monitoring during actual sonar exercises revealed some beaked whales
continuing to forage at levels up to 157 dB re: 1 [micro]Pa (Tyack et
al., 2011). Stimpert et al. (2014) tagged a Baird's beaked whale, which
was subsequently exposed to simulated MFAS. Changes in the animal's
dive behavior and locomotion were observed when received level reached
127 dB re: 1 [mu]Pa. However, Manzano-Roth et al. (2013) found that for
beaked whale dives that continued to occur during MFAS activity,
differences from normal dive profiles and click rates were not detected
with estimated received levels up to 137 dB re: 1 [micro]Pa while the
animals were at depth during their dives. In research done at the
Navy's fixed tracking range in the Bahamas, animals were observed to
leave the immediate area of the anti-submarine warfare training
exercise (avoiding the sonar acoustic footprint at a distance where the
received level was ``around 140 dB SPL'', according to Tyack et al.
(2011)), but return within a few days after the event ended (Claridge
and Durban, 2009; McCarthy et al., 2011; Moretti et al., 2009, 2010;
Tyack et al., 2010, 2011). Tyack et al. (2011) report that, in reaction
to sonar playbacks, most beaked whales stopped echolocating, made long
slow ascent to the surface, and moved away from the sound. A similar
behavioral response study conducted in Southern California waters
during the 2010-2011 field season found that Cuvier's beaked whales
exposed to MFAS displayed behavior ranging from initial orientation
changes to avoidance responses characterized by energetic fluking and
swimming away from the source (DeRuiter et al., 2013b). However, the
authors did not detect similar responses to incidental exposure to
distant naval sonar exercises at comparable received levels, indicating
that context of the exposures (e.g., source proximity, controlled
source ramp-up) may have been a significant factor. The study itself
found the results inconclusive and meriting further investigation.
Cuvier's beaked whale responses suggested particular sensitivity to
sound exposure consistent

[[Page 34030]]

with results for Blainville's beaked whale.
Populations of beaked whales and other odontocetes on the Bahamas
and other Navy fixed ranges that have been operating for decades appear
to be stable. Behavioral reactions (avoidance of the area of Navy
activity) seem likely in most cases if beaked whales are exposed to
anti-submarine sonar within a few tens of kilometers, especially for
prolonged periods (a few hours or more) since this is one of the most
sensitive marine mammal groups to anthropogenic sound of any species or
group studied to date and research indicates beaked whales will leave
an area where anthropogenic sound is present (De Ruiter et al., 2013;
Manzano-Roth et al., 2013; Moretti et al., 2014; Tyack et al., 2011).
Research involving tagged Cuvier's beaked whales in the SOCAL Range
Complex reported on by Falcone and Schorr (2012, 2014) indicates year-
round prolonged use of the Navy's training and testing area by these
beaked whales and has documented movements in excess of hundreds of
kilometers by some of those animals. Given that some of these animals
may routinely move hundreds of kilometers as part of their normal
pattern, leaving an area where sonar or other anthropogenic sound is
present may have little, if any, cost to such an animal. Photo
identification studies in the SOCAL Range Complex, a Navy range that is
utilized for training and testing, have identified approximately 100
Cuvier's beaked whale individuals with 40 percent having been seen in
one or more prior years, with re-sightings up to seven years apart
(Falcone and Schorr, 2014). These results indicate long-term residency
by individuals in an intensively used Navy training and testing area,
which may also suggest a lack of long-term consequences as a result of
exposure to Navy training and testing activities. More than eight years
of passive acoustic monitoring on the Navy's instrumented range west of
San Clemente Island documented no significant changes in annual and
monthly beaked whale echolocation clicks, with the exception of
repeated fall declines likely driven by natural beaked whale life
history functions (DiMarzio et al., 2018). Finally, results from
passive acoustic monitoring estimated that regional Cuvier's beaked
whale densities were higher than indicated by NMFS' broad scale visual
surveys for the United States West Coast (Hildebrand and McDonald,
2009).
Below we compile and summarize the information that supports our
preliminary determination that the Navy's activities would not
adversely affect beaked whales through effects on annual rates of
recruitment or survival.
Baird's and Cuvier's Beaked Whales and Mesoplodon Species (California/
Oregon/Washington Stocks)
The CA/OR/WA stocks of Baird's beaked whale, Cuvier's beaked whale,
and Mesoplodon species are not listed as endangered or threatened
species under the ESA, and have been identified as ``stable,''
``decreasing,'' and ``increasing,'' respectively, in the SARs. There
are no biologically important areas for beaked whales in the NWTT Study
Area. No mortality or Level A harassment from sonar or explosives is
expected or proposed for authorization.
No methods are available to distinguish between the six species of
Mesoplodon beaked whales from the CA/OR/WA stocks (Blainville's beaked
whale (M. densirostris), Perrin's beaked whale (M. perrini), Lesser
beaked whale (M. peruvianus), Stejneger's beaked whale (M. stejnegeri),
Gingko-toothed beaked whale (M. gingkodens), and Hubbs' beaked whale
(M. carlhubbsi)) when observed during at-sea surveys (Carretta et al.,
2019). Bycatch and stranding records from the region indicate that
Hubb's beaked whale is the most commonly encountered (Carretta et al.,
2008, Moore and Barlow, 2013). As indicated in the SAR, no species-
specific abundance estimates are available, the abundance estimate
includes all CA/OR/WA Mesoplodon species, and the six species are
managed as one unit. Due to the lack of species-specific abundance
estimates it is not possible to predict the take of individual species
and take estimates are identified as Mesoplodon species. Therefore our
analysis considers these Mesoplodon species together.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance is 36 to 78 percent. This information
indicates that up to 78 percent of the individuals in these stocks are
likely to be impacted, depending on the stock, though the more likely
scenario is that a smaller portion than that would be taken, and a
subset of them would be taken on a few days, with no indication that
these days would be sequential. Regarding the severity of those
individual Level B harassment takes by behavioral disruption, we have
explained that the duration of any exposure is expected to be between
minutes and hours (i.e., relatively short) and the received sound
levels largely below 166 dB, though with beaked whales, which are
considered somewhat more sensitive, this could mean that some
individuals will leave preferred habitat for a day (i.e., moderate
level takes). However, while interrupted feeding bouts are a known
response and concern for odontocetes, we also know that there are often
viable alternative habitat options nearby. Regarding the severity of
TTS takes, they are expected to be low-level, of short duration, and
mostly not in a frequency band that would be expected to interfere with
beaked whale communication or other important low-frequency cues, and
that the associated lost opportunities and capabilities are not at a
level that would impact reproduction or survival. As mentioned earlier
in the odontocete overview, we anticipate more severe effects from
takes when animals are exposed to higher received levels or sequential
days of impacts.
Altogether, none of these species are listed as threatened or
endangered under the ESA, only a portion of the stocks are anticipated
to be impacted, and any individual beaked whale is likely to be
disturbed at a moderate or sometimes low level. This low magnitude and
low to moderate severity of harassment effects is not expected to
result in impacts on individual reproduction or survival, let alone
annual rates of recruitment or survival. No mortality and no Level A
harassment is anticipated or proposed for authorization. For these
reasons, we have preliminarily determined, in consideration of all of
the effects of the Navy's activities combined, that the proposed
authorized take would have a negligible impact on the CA/OR/WA stocks
of beaked whales.

Dolphins and Small Whales

This section builds on the broader odontocete discussion above and
brings together the discussion of the different types and amounts of
take that different dolphin and small whale species and stocks would
likely incur, the applicable mitigation for stocks, and the status of
the species and stocks to support the preliminary negligible impact
determinations for each species or stock. For all dolphin and small
whale stocks discussed here except for the CA/OR/WA stocks of Northern
right whale dolphin and Pacific white-sided dolphin there is no
predicted PTS from sonar or explosives, and no mortality or tissue
damage from sonar or explosives is anticipated or proposed for
authorization. For the CA/OR/WA stocks of Northern right whale dolphin
and Pacific white-sided dolphin no mortality or tissue damage from
sonar or explosives is anticipated or proposed for authorization and
one Level A

[[Page 34031]]

harassment by PTS from testing activities is predicted for each stock.
In Table 55 below for dolphins and small whales, we indicate the
total annual numbers of take by mortality, Level A harassment and Level
B harassment, and a number indicating the instances of total take as a
percentage of abundance.
[GRAPHIC] [TIFF OMITTED] TP02JN20.011

As described above, the large majority of Level B behavioral
harassment to odontocetes, and thereby dolphins and small whales, from
hull-mounted sonar (MFAS) in the NWTT Study Area would result from
received levels between 160 and 172 dB SPL. Therefore, the majority of
Level B harassment takes are expected to be in the form of low to
occasionally moderate responses of a generally shorter duration. As
mentioned earlier in this section, we anticipate more severe effects
from takes when animals are exposed to higher received levels.
Occasional milder occurrences of Level B behavioral harassment are
unlikely to cause long-term consequences for individual animals or
populations that have any effect on reproduction or survival.
Research and observations show that if delphinids are exposed to
sonar or other active acoustic sources they may react in a number of
ways depending on their experience with the sound source and what
activity they are engaged in at the time of the acoustic exposure.
Delphinids may not react at all until the sound source is approaching
within a few hundred meters to within a few kilometers depending on the
environmental conditions and species. Some dolphin species (the more
surface-dwelling taxa--typically those with ``dolphin'' in the common
name, such as bottlenose dolphins, spotted dolphins, spinner dolphins,
rough-toothed dolphins, etc., but not Risso's dolphin), especially
those residing in more industrialized or busy areas, have demonstrated
more tolerance for disturbance and loud sounds and many

[[Page 34032]]

of these species are known to approach vessels to bow-ride. These
species are often considered generally less sensitive to disturbance.
Dolphins and small whales that reside in deeper waters and generally
have fewer interactions with human activities are more likely to
demonstrate more typical avoidance reactions and foraging interruptions
as described above in the odontocete overview.
Below we compile and summarize the information that supports our
preliminary determination that the Navy's activities would not
adversely affect dolphins and small whales through effects on annual
rates of recruitment or survival.
Killer Whales (Eastern North Pacific Alaskan Resident, West Coast
Transient, Eastern North Pacific Offshore, and Eastern North Pacific
Southern Resident Stocks)
With the exception of the Eastern North Pacific Southern Resident
stock (Southern Resident killer whale DPS) which is listed as
endangered under the ESA, killer whale stocks in the NWTT Study Area
are not listed under the ESA. ESA-designated critical habitat for the
Southern Resident killer whale DPS overlaps with the NWTT Study area in
the Strait of Juan de Fuca. No biologically important areas for killer
whales have been identified in the NWTT Study Area. The Eastern North
Pacific Southern Resident stock is small (75 individuals) and has been
decreasing in recent years. The Eastern North Pacific Offshore stock is
reported as ``stable'', and the other stocks have unknown population
trends. No mortality or Level A harassment is anticipated or proposed
for authorization for any of these stocks.
The proposed Marine Species Coastal, Olympic Coast National Marine
Sanctuary, Stonewall and Heceta Bank Humpback Whale, Point St. George
Humpback Whale, and Puget Sound and Strait of Juan de Fuca Mitigation
Areas overlap with important Eastern North Pacific Southern Resident
(Southern Resident DPS) killer whale foraging and migration habitat.
Procedural mitigation along with the mitigation measures implemented in
each of these areas include no MF1 MFAS use seasonally or limited MFAS
use year round, no explosive training, etc. (see details for each area
in the Proposed Mitigation Measures section), would reduce the severity
of impacts to Eastern North Pacific Southern Resident (Southern
Resident DPS) killer whales by reducing interference in feeding and
migration that could result in lost feeding opportunities or
necessitate additional energy expenditure to find other good foraging
opportunities or migration routes.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance ranges from 1 percent (Eastern North Pacific
Alaskan Resident) to 95 percent (West Coast Transient). The number of
estimated total instances of take compared to the abundance for the
Eastern North Pacific Southern Resident is 68 percent. This information
indicates that only a very small portion of the Eastern North Pacific
Alaskan Resident stock is likely impacted and repeated exposures of
individuals are not anticipated. This information also indicates that a
few to up to 95 percent of individuals of the remaining three stocks
could be impacted, if each were taken only one day per year, though the
more likely scenario is that a smaller portion than that would be
taken, and a subset of them would be taken multiple days with no
indication that these days would be sequential. Regarding the severity
of those individual Level B harassment takes by behavioral disruption,
we have explained that the duration of any exposure is expected to be
between minutes and hours (i.e., relatively short) and the received
sound levels largely below 172 dB (i.e., of a lower, to occasionally
moderate, level and less likely to evoke a severe response). Regarding
the severity of TTS takes, they are expected to be low-level, of short
duration, and mostly not in a frequency band that would be expected to
interfere with killer whale communication or other important low-
frequency cues, and that the associated lost opportunities and
capabilities are not at a level that would impact reproduction or
survival.
Altogether, with the exception of the Eastern North Pacific
Southern Resident stock which is listed as endangered under the ESA,
these killer whale stocks are not listed under the ESA. Only a portion
of these killer whale stocks is anticipated to be impacted, and any
individual is likely to be disturbed at a low-moderate level, with the
taken individuals likely exposed on one day or a few days. Even
acknowledging the small and declining stock size of the Eastern North
Pacific Southern Resident stock, this low magnitude and severity of
harassment effects is unlikely to result in impacts on individual
reproduction or survival, much less annual rates of recruitment or
survival of any of the stocks. No mortality or Level A harassment is
anticipated or proposed for authorization for any of the stocks. For
these reasons, we have preliminarily determined, in consideration of
all of the effects of the Navy's activities combined, that the proposed
authorized take would have a negligible impact on these killer whale
stocks.
All other dolphin and small whale stocks
None of these stocks is listed under the ESA and their stock
statuses are considered ``unknown,'' except for the CA/OR/WA stock of
short-beaked common dolphin which is described as ``increasing''. No
biologically important areas for these stocks have been identified in
the NWTT Study Area. No mortality or serious injury is anticipated or
proposed for authorization. With the exception of one Level A
harassment PTS take to the CA/OR/WA stocks of Northern right whale
dolphin and Pacific white-sided dolphin, no Level A harassment by PTS
or tissue damage is expected or proposed for authorization for these
stocks.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance ranges from less than 1 percent (North
Pacific stock of Pacific white-sided dolphins, CA/OR/WA Offshore stock
of common bottlenose dolphins, and CA/OR/WA stock of short-beaked
common dolphin) to 100 percent (CA/OR/WA stock of Risso's dolphins).
All stocks except for the CA/OR/WA stocks of Risso's dolphin, Pacific
white-sided dolphin, and Northern right whale dolphin have estimated
total instances of take compared to the abundances less than or equal
to 11 percent. This information indicates that only a small portion of
these stocks is likely impacted and repeated exposures of individuals
are not anticipated. The CA/OR/WA stocks of Risso's dolphins, Pacific
white-sided dolphin, and Northern right whale dolphin have estimated
total instances of take compared to the abundances that range from 78
to 100 percent. This information indicates that up to 100 percent of
the individuals of these stocks could be impacted, if each were taken
only one day per year, though the more likely scenario is that a
smaller portion than that would be taken, and a subset of them would be
taken on a few days, with no indication that these days would be
sequential. Regarding the severity of those individual Level B
harassment takes by behavioral disruption, we have explained that the
duration of any exposure is expected to be between minutes and hours
(i.e., relatively short) and the received sound levels largely below
172 dB (i.e., of a

[[Page 34033]]

lower, to occasionally moderate, level and less likely to evoke a
severe response). However, while interrupted feeding bouts are a known
response and concern for odontocetes, we also know that there are often
viable alternative habitat options nearby. Regarding the severity of
TTS takes, they are expected to be low-level, of short duration, and
mostly not in a frequency band that would be expected to interfere with
dolphin and small whale communication or other important low-frequency
cues, and that the associated lost opportunities and capabilities are
not at a level that would impact reproduction or survival. For these
same reasons (low level and frequency band), while a small permanent
loss of hearing sensitivity (PTS) may include some degree of energetic
costs for compensating or may mean some small loss of opportunities or
detection capabilities, at the expected scale the estimated one Level A
harassment take by PTS for the CA/OR/WA stocks of Northern right whale
dolphin and Pacific white-sided dolphin would be unlikely to impact
behaviors, opportunities, or detection capabilities to a degree that
would interfere with reproductive success or survival of that
individual. Thus the one Level A harassment take by PTS for these
stocks would be unlikely to affect rates of recruitment and survival
for the stock.
Altogether, though the status of these stocks is largely unknown,
none of these stocks is listed under the ESA and any individual is
likely to be disturbed at a low-moderate level, with the taken
individuals likely exposed on one to a few days. This low magnitude and
severity of harassment effects is not expected to result in impacts on
individual reproduction or survival. One individual each from the CA/
OR/WA stocks of Northern right whale dolphin and Pacific white-sided
dolphin could be taken by PTS annually of likely low severity. A small
permanent loss of hearing sensitivity (PTS) may include some degree of
energetic costs for compensating or may mean some small loss of
opportunities or detection capabilities, but at the expected scale the
estimated Level A harassment takes by PTS for the CA/OR/WA stocks of
Northern right whale dolphin and Pacific white-sided dolphin would be
unlikely to impact behaviors, opportunities, or detection capabilities
to a degree that would interfere with reproductive success or survival
of any individuals, let alone annual rates of recruitment or survival.
No mortality is anticipated or proposed for authorization. For these
reasons, we have preliminarily determined, in consideration of all of
the effects of the Navy's activities combined, that the proposed
authorized take would have a negligible impact on these stocks of small
whales and dolphins.

Porpoises

This section builds on the broader odontocete discussion above and
brings together the discussion of the different types and amounts of
take that different porpoise species or stocks would likely incur, the
applicable mitigation, and the status of the species and stock to
support the negligible impact determinations for each species or stock.
For porpoises, there is no anticipated M/SI or tissue damage from sonar
or explosives for any species.
In Table 56 below for porpoises, we indicate the total annual
numbers of take by mortality, Level A harassment and Level B
harassment, and a number indicating the instances of total take as a
percentage of abundance.
[GRAPHIC] [TIFF OMITTED] TP02JN20.012

The majority of takes by harassment of harbor porpoises in the NWTT
Study Area are caused by sources from the MFAS bin (which includes
hull-mounted sonar) because they are high level sources at a frequency
(1-10 kHz), which overlaps a more sensitive portion (though not the
most sensitive) of the HF hearing range, and of the sources expected to
result in take, they are used in a large portion of exercises (see
Tables 3 and 4). Most of the takes (90

[[Page 34034]]

percent) from the MF1 bin in the NWTT Study Area would result from
received levels between 148 and 166 dB SPL. For the remaining active
sonar bin types, the percentages are as follows: LF4 = 99 percent
between 124 and 142 dB SPL, MF4 = 97 percent between 124 and 148 dB
SPL, MF5 = 97 percent between 118 and 142 dB SPL, and HF4 = 97 percent
between 118 and 160 dB SPL. Given the levels they are exposed to and
harbor porpoise sensitivity, some responses would be of a lower
severity, but many would likely be considered moderate, but still of
generally short duration.
Harbor porpoises have been shown to be particularly sensitive to
human activity (Tyack et al., 2011; Pirotta et al., 2012). The
information currently available regarding harbor porpoises suggests a
very low threshold level of response for both captive (Kastelein et
al., 2000; Kastelein et al., 2005) and wild (Johnston, 2002) animals.
Southall et al. (2007) concluded that harbor porpoises are likely
sensitive to a wide range of anthropogenic sounds at low received
levels (approximately 90 to 120 dB). Research and observations of
harbor porpoises for other locations show that this species is wary of
human activity and will display profound avoidance behavior for
anthropogenic sound sources in many situations at levels down to 120 dB
re: 1 [micro]Pa (Southall, 2007). Harbor porpoises routinely avoid and
swim away from large motorized vessels (Barlow et al., 1988; Evans et
al., 1994; Palka and Hammond, 2001; Polacheck and Thorpe, 1990). Harbor
porpoises may startle and temporarily leave the immediate area of the
training or testing until after the event ends. Accordingly, harbor
porpoises have been assigned a lower Level B behavioral harassment
threshold, i.e., a more distant distance cutoff (40 km for high source
level, 20 km for moderate source level) and, as a result, the number of
harbor porpoise taken by Level B behavioral harassment through exposure
to LFAS/MFAS/HFAS in the NWTT Study Area is generally higher than the
other species. As mentioned earlier in the odontocete overview, we
anticipate more severe effects from takes when animals are exposed to
higher received levels or sequential days of impacts; occasional low to
moderate behavioral reactions are unlikely to affect reproduction or
survival. Some takes by Level B behavioral harassment could be in the
form of a longer (several hours or a day) and more moderate response,
but unless they are repeated over more than several sequential days,
impacts to reproduction or survival are not anticipated. Even where
some smaller number of animals could experience effects on reproduction
(which could happen to a small number), for the reasons explained below
this would not affect rates of recruitment or survival, especially
given the status of the stocks.
While harbor porpoises have been observed to be especially
sensitive to human activity, the same types of responses have not been
observed in Dall's porpoises. Dall's porpoises are typically notably
longer than, and weigh more than twice as much as, harbor porpoises,
making them generally less likely to be preyed upon and likely
differentiating their behavioral repertoire somewhat from harbor
porpoises. Further, they are typically seen in large groups and feeding
aggregations, or exhibiting bow-riding behaviors, which is very
different from the group dynamics observed in the more typically
solitary, cryptic harbor porpoises, which are not often seen bow-
riding. For these reasons, Dall's porpoises are not treated as an
especially sensitive species (versus harbor porpoises which have a
lower behavioral harassment threshold and more distant cutoff) but,
rather, are analyzed similarly to other odontocetes (with takes from
the sonar bin in the NWTT Study Area resulting from the same received
levels reported in the Odontocete section above). Therefore, the
majority of Level B takes are expected to be in the form of milder
responses compared to higher level exposures. As mentioned earlier in
this section, we anticipate more severe effects from takes when animals
are exposed to higher received levels.
All Porpoise Stocks
These Dall's and harbor porpoise stocks are not listed under the
ESA and the status of these stocks is considered ``unknown.'' There are
no biologically important areas for Dall's and harbor porpoises in the
NWTT Study Area. However, a known important feeding area for harbor
porpoises overlaps with the Stonewall and Heceta Bank Humpback Whale
Mitigation Area. No MF1 MFAS or explosives would be used in this
mitigation area from May 1--November 30, which would reduce the
severity of impacts to harbor porpoises by reducing interference in
feeding that could result in lost feeding opportunities or necessitate
additional energy expenditure to find other good opportunities. No
mortality or Level A harassment from tissue damage is expected or
proposed to be authorized for any of these stocks.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance ranges from less than 1 percent for the
Alaska stock of Dall's porpoises to 265 percent for the Washington
Inland Waters stock of harbor porpoises. The Alaska stock of Dall's
porpoises, and Southeast Alaska and Northern California/Southern Oregon
stocks of harbor porpoises have estimated total instances of take
compared to the abundances less than or equal to 10 percent. This
information indicates that only a small portion of these stocks is
likely impacted and repeated exposures of individuals are not
anticipated. The CA/OR/WA stock of Dall's porpoises and the Northern
Washington/Oregon Coast and Washington Inland Waters stocks of harbor
porpoises have estimated total instances of take compared to the
abundances that range from 131 to 265 percent. This information
indicates that all individuals of these stocks could be impacted, if
each were taken two to three days per year, though the more likely
scenario is that a smaller portion would be taken, and a subset of
those would be on more days (maybe 5 or 6), with no indication that
these days would be sequential. Given this and the larger number of
total takes (totally and to individuals), it is more likely
(probabilistically) that some small number of individuals could be
interrupted during foraging in a manner and amount such that impacts to
the energy budgets of females (from either losing feeding opportunities
or expending considerable energy to find alternative feeding options)
could cause them to forego reproduction for a year. Energetic impacts
to males are generally meaningless to population rates unless they
cause death, and it takes extreme energy deficits beyond what would
ever be likely to result from these activities to cause the death of an
adult marine mammal. However, foregone reproduction (especially for
only one year within seven, which is the maximum predicted because the
small number anticipated in any one year makes the probability that any
individual will be impacted in this way twice in seven years very low)
has far less of an impact on population rates than mortality and a
small number of instances would not be expected to adversely impact
annual rates of recruitment or survival. All indications are that the
number of times in which reproduction would be likely to be foregone
would not affect the stocks' annual rates of recruitment or survival.
Regarding the severity of those individual Level B harassment takes
by

[[Page 34035]]

behavioral disruption for harbor porpoises, we have explained that the
duration of any exposure is expected to be between minutes and hours
(i.e., relatively short) and the received sound levels largely below
166 dB, which for harbor porpoise (which have a lower behavioral Level
B harassment threshold) would mostly be considered a moderate level.
Regarding the severity of those individual Level B harassment takes by
behavioral disruption for Dall's porpoises, we have explained that the
duration of any exposure is expected to be between minutes and hours
(i.e., relatively short) and the received sound levels largely below
172 dB (i.e., of a lower, to occasionally moderate, level and less
likely to evoke a severe response). Regarding the severity of TTS
takes, they are expected to be low-level, of short duration, and mostly
not in a frequency band that would be expected to interfere with
communication or other important low-frequency cues. The associated
lost opportunities and capabilities are not at a level that would
impact reproduction or survival.
No Level A harassment by PTS is anticipated or proposed for the
Southeast Alaska stock of harbor porpoise or the Alaska stock of Dall's
porpoise. For the remaining porpoise stocks, for the same reasons
explained above for TTS (low level and the likely frequency band),
while a small permanent loss of hearing sensitivity may include some
degree of energetic costs for compensating or may mean some small loss
of opportunities or detection capabilities, the estimated annual Level
A harassment takes by PTS for these three stocks of harbor porpoises
and one stock of Dall's porpoises (86 to 180) would be unlikely to
impact behaviors, opportunities, or detection capabilities to a degree
that would interfere with reproductive success or survival for most
individuals. Because of the higher number of PTS takes, however, we
acknowledge that a few animals could potentially incur permanent
hearing loss of a higher degree that could potentially interfere with
their successful reproduction and growth. Given the large population
sizes of these stocks, even if these occurred, it would not adversely
impact rates of recruitment or survival.
Altogether, the status of the harbor porpoise stocks is unknown,
however harbor porpoises are not listed as endangered or threatened
under the ESA. Because harbor porpoises are particularly sensitive, it
is likely that a fair number of the Level B behavioral responses of
individuals will be of a moderate nature. Additionally, as noted, some
portion of the stocks may be taken repeatedly on up to several days
within a year, however this is not anticipated to affect the stocks'
annual rates of recruitment or survival. Some individuals (86 to 180)
from the Northern Oregon/Washington Coast, Northern California/Southern
Oregon, and Washington Inland Waters stocks of harbor porpoises could
be taken by PTS annually of likely low severity. A small permanent loss
of hearing sensitivity (PTS) may include some degree of energetic costs
for compensating or may mean some small loss of opportunities or
detection capabilities, but at the expected scale the estimated Level A
harassment takes by PTS for these stocks would be unlikely to impact
behaviors, opportunities, or detection capabilities to a degree that
would interfere with reproductive success or survival of any
individuals, let alone annual rates of recruitment or survival. No
mortality is anticipated or proposed for authorization. For these
reasons, we have preliminarily determined, in consideration of all of
the effects of the Navy's activities combined, that the proposed
authorized take would have a negligible impact on all four stocks of
harbor porpoises. Altogether, the status of the Dall's porpoise stocks
is unknown, however Dall's porpoises are not listed as endangered or
threatened under the ESA. Any individual Dall's porpoise is likely to
be disturbed at a low-moderate level, with the taken individuals likely
exposed on one to a few days. This low magnitude and severity of Level
B harassment effects is not expected to result in impacts on individual
reproduction or survival, much less annual rates of recruitment or
survival. Some individuals (98) from the CA/OR/WA stock of Dall's
porpoises could be taken by PTS annually of likely low severity. A
small permanent loss of hearing sensitivity (PTS) may include some
degree of energetic costs for compensating or may mean some small loss
of opportunities or detection capabilities, but at the expected scale
the estimated Level A harassment takes by PTS for this stock would be
unlikely to impact behaviors, opportunities, or detection capabilities
to a degree that would interfere with reproductive success or survival
of any individuals, let alone annual rates of recruitment or survival.
No mortality is anticipated or proposed for authorization. For these
reasons, we have preliminarily determined, in consideration of all of
the effects of the Navy's activities combined, that the proposed
authorized take would have a negligible impact on these stocks of
Dall's porpoises.
Pinnipeds
This section builds on the broader discussion above and brings
together the discussion of the different types and amounts of take that
different species and stocks would likely incur, the applicable
mitigation, and the status of the species and stocks to support the
negligible impact determinations for each species or stock. We have
described (earlier in this section) the unlikelihood of any masking
having effects that would impact the reproduction or survival of any of
the individual marine mammals affected by the Navy's activities. We
have also described above in the Potential Effects of Specified
Activities on Marine Mammals and their Habitat section the unlikelihood
of any habitat impacts having effects that would impact the
reproduction or survival of any of the individual marine mammals
affected by the Navy's activities. For pinnipeds, there is no mortality
or serious injury and no Level A harassment from tissue damage from
sonar or explosives anticipated or proposed to be authorized for any
species. Here, we include information that applies to all of the
pinniped species.
In Table 57 below for pinnipeds, we indicate the total annual
numbers of take by mortality, Level A harassment and Level B
harassment, and a number indicating the instances of total take as a
percentage of abundance.

[[Page 34036]]

[GRAPHIC] [TIFF OMITTED] TP02JN20.013

The majority of takes by harassment of pinnipeds in the NWTT Study
Area are caused by sources from the MFAS bin (which includes hull-
mounted sonar) because they are high level sources at a frequency (1-10
kHz) which overlaps the most sensitive portion of the pinniped hearing
range, and of the sources expected to result in take, they are used in
a large portion of exercises (see Tables 3 and 4). Most of the takes
(97 percent) from the MF1 bin in the NWTT Study Area would result from
received levels between 166 and 178 dB SPL. For the remaining active
sonar bin types, the percentages are as follows: LF4 = 97 percent
between 130 and 160 dB SPL, MF4 = 99 percent between 142 and 172 dB
SPL, MF5 = 97 percent between 130 and 160 dB SPL, and HF4 = 99 percent
between 100 and 172 dB SPL. Given the levels they are exposed to and
pinniped sensitivity, most responses would be of a lower severity, with
only occasional responses likely to be considered moderate, but still
of generally short duration.
As mentioned earlier in this section, we anticipate more severe
effects from takes when animals are exposed to higher received levels.
Occasional milder takes by Level B behavioral harassment are unlikely
to cause long-term consequences for individual animals or populations,
especially when they are not expected to be repeated over sequential
multiple days. For all pinnipeds, harassment takes from explosives
(behavioral, TTS, or PTS if present) comprise a very small fraction of
those caused by exposure to active sonar.
Because the majority of harassment take of pinnipeds results from
narrowband sources in the range of 1-10 kHz, the vast majority of
threshold shift caused by Navy sonar sources will typically occur in
the range of 2-20 kHz. This frequency range falls within the range of
pinniped hearing, however, pinniped vocalizations typically span a
somewhat lower range than this (<0.2 to 10 kHz) and threshold shift
from active sonar will often be in a narrower band (reflecting the
narrower band source that caused it), which means that TTS incurred by
pinnipeds would typically only interfere with communication within a
portion of a pinniped's range (if it occurred during a time when

[[Page 34037]]

communication with conspecifics was occurring). As discussed earlier,
it would only be expected to be of a short duration and relatively
small degree. Many of the other critical sounds that serve as cues for
navigation and prey (e.g., waves, fish, invertebrates) occur below a
few kHz, which means that detection of these signals will not be
inhibited by most threshold shifts either. The very low number of takes
by threshold shifts that might be incurred by individuals exposed to
explosives would likely be lower frequency (5 kHz or less) and spanning
a wider frequency range, which could slightly lower an individual's
sensitivity to navigational or prey cues, or a small portion of
communication calls, for several minutes to hours (if temporary) or
permanently.
Regarding behavioral disturbance, research and observations show
that pinnipeds in the water may be tolerant of anthropogenic noise and
activity (a review of behavioral reactions by pinnipeds to impulsive
and non-impulsive noise can be found in Richardson et al. (1995) and
Southall et al. (2007)). Available data, though limited, suggest that
exposures between approximately 90 and 140 dB SPL do not appear to
induce strong behavioral responses in pinnipeds exposed to non-pulse
sounds in water (Costa et al., 2003; Jacobs and Terhune, 2002;
Kastelein et al., 2006c). Based on the limited data on pinnipeds in the
water exposed to multiple pulses (small explosives, impact pile
driving, and seismic sources), exposures in the approximately 150 to
180 dB SPL range generally have limited potential to induce avoidance
behavior in pinnipeds (Blackwell et al., 2004; Harris et al., 2001;
Miller et al., 2004). If pinnipeds are exposed to sonar or other active
acoustic sources they may react in a number of ways depending on their
experience with the sound source and what activity they are engaged in
at the time of the acoustic exposure. Pinnipeds may not react at all
until the sound source is approaching within a few hundred meters and
then may alert, ignore the stimulus, change their behaviors, or avoid
the immediate area by swimming away or diving. Effects on pinnipeds
that are taken by Level B harassment in the NWTT Study Area, on the
basis of reports in the literature as well as Navy monitoring from past
activities, will likely be limited to reactions such as increased
swimming speeds, increased surfacing time, or decreased foraging (if
such activity were occurring). Most likely, individuals will simply
move away from the sound source and be temporarily displaced from those
areas, or not respond at all, which would have no effect on
reproduction or survival. In areas of repeated and frequent acoustic
disturbance, some animals may habituate or learn to tolerate the new
baseline or fluctuations in noise level. Habituation can occur when an
animal's response to a stimulus wanes with repeated exposure, usually
in the absence of unpleasant associated events (Wartzok et al., 2003).
While some animals may not return to an area, or may begin using an
area differently due to training and testing activities, most animals
are expected to return to their usual locations and behavior. Given
their documented tolerance of anthropogenic sound (Richardson et al.,
1995 and Southall et al., 2007), repeated exposures of individuals of
any of these species to levels of sound that may cause Level B
harassment are unlikely to result in hearing impairment or to
significantly disrupt foraging behavior. Thus, even repeated Level B
harassment of some small subset of individuals of an overall stock is
unlikely to result in any significant realized decrease in fitness to
those individuals that would result in any adverse impact on rates of
recruitment or survival for the stock as a whole.
Of these stocks, only Guadalupe fur seals are listed as threatened
under the ESA and the SAR indicates the stock is ``increasing.'' No
critical habitat under the ESA is designated for the Guadalupe fur
seal. The other stocks are not ESA-listed. Biologically important areas
have not been identified for pinnipeds. There are active UMEs for
Guadalupe fur seals and California sea lions. Since 2015 there have
been 400 strandings of Guadalupe fur seals (including live and dead
seals). The California sea lion UME is anticipated to be closed soon as
elevated strandings occurred from 2013-2016. All of the other pinniped
stocks are considered ``increasing,'' ``stable,'' or ``unknown'' except
for Northern fur seals (Eastern Pacific stock), which is considered
``declining''. No mortality or Level A harassment from tissue damage is
anticipated or proposed for authorization. All the pinniped species
discussed in this section would benefit from the procedural mitigation
measures described earlier in the Proposed Mitigation Measures section.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), for Guadalupe fur seals, the estimated
instances of takes as compared to the stock abundance is 4 percent.
This information indicates that only a small portion of individuals in
the stock are likely impacted and repeated exposures of individuals are
not anticipated. With the exception of the Hood Canal and Southern
Puget Sound stocks of harbor seals, for the remaining stocks the number
of estimated total instances of take compared to the abundance is 2-15
percent. Given the ranges of these stocks (i.e., large ranges, but with
individuals often staying in the vicinity of haulouts), this
information indicates that a small portion of individuals in the stock
are likely impacted and repeated exposures of individuals are not
anticipated. For the Southern Puget Sound stock of harbor seals, the
number of estimated total instances of take compared to the abundance
is 168 percent. This information indicates that all individuals in this
stock could be impacted, if each were taken up to 1-2 days per year,
though the more likely scenario is that a smaller portion than that
would be taken, and a subset of them would be taken on 3 or 4 days,
with no indication that these days would be sequential.
For the Hood Canal stock of harbor seals, the number of estimated
total instances of take compared to the abundance is 3,084 percent.
This information indicates that all individuals of this stock could be
impacted, if each were taken up to 31 days per year, though the more
likely scenario is that a subset of them would be taken on fewer than
31 days and a subset would be taken on more than 31 days, and for those
taken on a higher number of days, some of those days may be sequential.
Though the majority of impacts are expected to be of a lower to
sometimes moderate severity, the repeated takes over a potentially fair
number of sequential days for some individuals in the Hood Canal stock
of harbor seals makes it more likely that some number of individuals
could be interrupted during foraging in a manner and amount such that
impacts to the energy budgets of females (from either losing feeding
opportunities or expending considerable energy to find alternative
feeding options) could cause them to forego reproduction for a year
(energetic impacts to males are generally meaningless to population
rates unless they cause death, and it takes extreme energy deficits
beyond what would ever be likely to result from these activities to
cause the death of an adult marine mammal). As noted previously,
however, foregone reproduction (especially for only one year within
seven, which is the maximum predicted because the small number
anticipated in any one year makes the probability that

[[Page 34038]]

any individual will be impacted in this way twice in seven years very
low) has far less of an impact on population rates than mortality and a
relatively small number of instances of foregone reproduction would not
be expected to adversely affect the stock through effects on annual
rates of recruitment or survival. Regarding the severity of those
individual takes by Level B behavioral harassment for all pinniped
stocks, we have explained that the duration of any exposure is expected
to be between minutes and hours (i.e., relatively short) and the
received sound levels largely below 178 dB, which is considered a
relatively low to occasionally moderate level for pinnipeds. However,
as noted, for the Hood Canal stock, some of these takes could occur on
some number of sequential days.
Regarding the severity of TTS takes, they are expected to be low-
level, of short duration, and mostly not in a frequency band that would
be expected to interfere with pinniped communication or other important
low-frequency cues, and that the associated lost opportunities and
capabilities are not at a level that would impact reproduction or
survival. For these same reasons (low level and frequency band), while
a small permanent loss of hearing sensitivity may include some degree
of energetic costs for compensating or may mean some small loss of
opportunities or detection capabilities, the 1-5 estimated Level A
harassment takes by PTS for California sea lions, Northern elephant
seals, and the Washington Northern inland waters, Hood Canal, OR/WA
Coast, and Southern Puget Sound stocks of harbor seals would be
unlikely to impact behaviors, opportunities, or detection capabilities
to a degree that would interfere with reproductive success or survival
of any individuals.
Altogether, all pinniped stocks are considered ``increasing,''
``stable,'' or ``unknown'' except for Northern fur seals (Eastern
Pacific stock), which is considered ``declining'' but is not listed
under the ESA. Only the Guadalupe fur seal is listed under the ESA,
with a population that is considered increasing. No mortality for
pinnipeds is anticipated or proposed for authorization. For nearly all
pinniped stocks (with the exception of the Hood Canal harbor seals)
only a portion of the stocks are anticipated to be impacted and any
individual is likely to be disturbed at a low-moderate level. Even
considering the effects of the UMEs on the Guadalupe fur seal and
California sea lion stocks, this low magnitude and severity of
harassment effects is not expected to result in impacts on individual
reproduction or survival, much less annual rates of recruitment or
survival. For the Hood Canal stock of harbor seals, a fair portion of
individuals will be taken by Level B harassment (at a moderate or
sometimes low level) over a comparatively higher number of days within
a year, and some smaller portion of those individuals may be taken on
sequential days, however this is not expected to adversely affect the
stock through effects on annual rates of recruitment or survival.
Accordingly, we do not anticipate the relatively small number of
individual harbor seals that might be taken over repeated days within
the year in a manner that results in one year of foregone reproduction
to adversely affect the stock through effects on rates of recruitment
or survival, given the status of the stock. For these reasons, in
consideration of all of the effects of the Navy's activities combined,
we have preliminarily determined that the proposed authorized take
would have a negligible impact on all stocks of pinnipeds.

Preliminary Determination

Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the
proposed monitoring and mitigation measures, NMFS preliminarily
finds that the total marine mammal take from the Specified Activities
will have a negligible impact on all affected marine mammal species or
stocks.

Subsistence Harvest of Marine Mammals

In order to issue an incidental take authorization, NMFS must find
that the specified activity will not have an ``unmitigable adverse
impact'' on the subsistence uses of the affected marine mammal species
or stocks by Alaskan Natives. NMFS has defined ``unmitigable adverse
impact'' in 50 CFR 216.103 as an impact resulting from the specified
activity: (1) That is likely to reduce the availability of the species
to a level insufficient for a harvest to meet subsistence needs by: (i)
Causing the marine mammals to abandon or avoid hunting areas; (ii)
Directly displacing subsistence users; or (iii) Placing physical
barriers between the marine mammals and the subsistence hunters; and
(2) That cannot be sufficiently mitigated by other measures to increase
the availability of marine mammals to allow subsistence needs to be
met.
To our knowledge there are no relevant subsistence uses of the
affected marine mammal stocks or species implicated by this action.
Therefore, NMFS has preliminarily determined that the total taking of
affected species or stocks would not have an unmitigable adverse impact
on the availability of the species or stocks for taking for subsistence
purposes. However, we have limited information on marine mammal
subsistence use in the Western Behm Canal area of southeastern Alaska
and seek additional information pertinent to making the final
determination.

Classification

Endangered Species Act

There are seven marine mammal species under NMFS jurisdiction that
are listed as endangered or threatened under the ESA with confirmed or
possible occurrence in the NWTT Study Area: Blue whale, fin whale,
humpback whale (Mexico and Central America DPSs), sei whale, sperm
whale, killer whale (Southern Resident killer whale DPS), and Guadalupe
fur seal. The Southern Resident killer whale has critical habitat
designated under the ESA in the NWTT Study Area. NMFS has recently
published two proposed rules, proposing new or revised ESA-designated
critical habitat for humpback whales (84 FR 54354; October 9, 2019) and
Southern Resident killer whales (84 FR 49214; September 19, 2019).
The Navy will consult with NMFS pursuant to section 7 of the ESA
for NWTT Study Area activities. NMFS will also consult internally on
the issuance of the regulations and LOAs under section 101(a)(5)(A) of
the MMPA.

National Marine Sanctuaries Act

NMFS will work with NOAA's Office of National Marine Sanctuaries to
fulfill our responsibilities under the National Marine Sanctuaries Act
as warranted and will complete any NMSA requirements prior to a
determination on the issuance of the final rule and LOAs.

National Environmental Policy Act

To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must evaluate our proposed actions and alternatives with respect
to potential impacts on the human environment. Accordingly, NMFS plans
to adopt the NWTT SEIS/OEIS for the NWTT Study Area provided our
independent evaluation of the document finds that it includes adequate
information analyzing the effects on the human environment of issuing
regulations and LOAs under the

[[Page 34039]]

MMPA. NMFS is a cooperating agency on the 2019 NWTT DSEIS/OEIS and has
worked extensively with the Navy in developing the document. The 2019
NWTT DSEIS/OEIS was made available for public comment at https://www.nwtteis.com in April, 2019. We will review all comments submitted
in response to this notice prior to concluding our NEPA process or
making a final decision on the MMPA rule and request for LOAs.

Regulatory Flexibility Act

The Office of Management and Budget has determined that this
proposed rule is not significant for purposes of Executive Order 12866.
Pursuant to the Regulatory Flexibility Act (RFA), the Chief Counsel
for Regulation of the Department of Commerce has certified to the Chief
Counsel for Advocacy of the Small Business Administration that this
proposed rule, if adopted, would not have a significant economic impact
on a substantial number of small entities. The RFA requires Federal
agencies to prepare an analysis of a rule's impact on small entities
whenever the agency is required to publish a notice of proposed
rulemaking. However, a Federal agency may certify, pursuant to 5 U.S.C.
605(b), that the action will not have a significant economic impact on
a substantial number of small entities. The Navy is the sole entity
that would be affected by this rulemaking, and the Navy is not a small
governmental jurisdiction, small organization, or small business, as
defined by the RFA. Any requirements imposed by an LOA issued pursuant
to these regulations, and any monitoring or reporting requirements
imposed by these regulations, would be applicable only to the Navy.
NMFS does not expect the issuance of these regulations or the
associated LOAs to result in any impacts to small entities pursuant to
the RFA. Because this action, if adopted, would directly affect the
Navy and not a small entity, NMFS concludes that the action would not
result in a significant economic impact on a substantial number of
small entities.

List of Subjects in 50 CFR Part 218

Exports, Fish, Imports, Incidental take, Indians, Labeling, Marine
mammals, Navy, Penalties, Reporting and recordkeeping requirements,
Seafood, Sonar, Transportation.

Dated: April 17, 2020.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs,National Marine
Fisheries Service.

For reasons set forth in the preamble, 50 CFR part 218 is proposed
to be amended as follows:

PART 218--REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE
MAMMALS

0
1. The authority citation for part 218 continues to read as follows:

Authority: 16 U.S.C. 1361 et seq., unless otherwise noted.

0
2. Revise subpart O to read as follows:
Subpart O--Taking and Importing Marine Mammals; U.S. Navy's Northwest
Training and Testing (NWTT)
Sec.
218.140 Specified activity and geographical region.
218.141 Effective dates.
218.142 Permissible methods of taking.
218.143 Prohibitions.
218.144 Mitigation requirements.
218.145 Requirements for monitoring and reporting.
218.146 Letters of Authorization.
218.147 Renewals and modifications of Letters of Authorization.
218.148 [Reserved]

Subpart O--Taking and Importing Marine Mammals; U.S. Navy's
Northwest Training and Testing (NWTT)

Sec. 218.140 Specified activity and geographical region.

(a) Regulations in this subpart apply only to the U.S. Navy (Navy)
for the taking of marine mammals that occurs in the area described in
paragraph (b) of this section and that occurs incidental to the
activities listed in paragraph (c) of this section.
(b) The taking of marine mammals by the Navy is only authorized if
it occurs within the NWTT Study Area, which is composed of established
maritime operating and warning areas in the eastern North Pacific Ocean
region, including areas of the Strait of Juan de Fuca, Puget Sound, and
Western Behm Canal in southeastern Alaska. The Study Area includes air
and water space within and outside Washington state waters, and outside
state waters of Oregon and Northern California. The eastern boundary of
the Offshore Area portion of the Study Area is 12 nautical miles (nmi)
off the coastline for most of the Study Area, including southern
Washington, Oregon, and Northern California. The Offshore Area includes
the ocean all the way to the coastline only along that part of the
Washington coast that lies beneath the airspace of W-237 and the
Olympic Military Operating Area (MOA) and the Washington coastline
north of the Olympic MOA. The Study Area includes four existing range
complexes and facilities: The Northwest Training Range Complex (NWTRC),
the Keyport Range Complex, the Carr Inlet Operations Area, and the
Southeast Alaska Acoustic Measurement Facility (SEAFAC). In addition to
these range complexes, the Study Area also includes Navy pierside
locations where sonar maintenance and testing occurs as part of
overhaul, modernization, maintenance, and repair activities at Naval
Base Kitsap, Bremerton; Naval Base Kitsap, Bangor; and Naval Station
Everett.
(c) The taking of marine mammals by the Navy is only authorized if
it occurs incidental to the Navy conducting training and testing
activities, including:
(1) Anti-submarine warfare;
(2) Expeditionary warfare;
(3) Mine warfare;
(4) Surface warfare; and
(5) Other training and testing activities.

Sec. 218.141 Effective dates.

Regulations in this subpart are effective from November 9, 2020
through November 8, 2027.

Sec. 218.142 Permissible methods of taking.

(a) Under Letters of Authorization (LOAs) issued pursuant to
Sec. Sec. 216.106 of this chapter and 218.146, the Holder of the LOAs
(hereinafter ``Navy'') may incidentally, but not intentionally, take
marine mammals within the area described in Sec. 218.140(b) by Level A
harassment and Level B harassment associated with the use of active
sonar and other acoustic sources and explosives, as well as serious
injury or mortality associated with vessel strikes, provided the
activity is in compliance with all terms, conditions, and requirements
of this subpart and the applicable LOAs.
(b) The incidental take of marine mammals by the activities listed
in Sec. 218.140(c) is limited to the following species:

[[Page 34040]]

Table 1 to Sec. 218.142
------------------------------------------------------------------------
Species Stock
------------------------------------------------------------------------
Blue whale............................. Eastern North Pacific.
Fin whale.............................. Northeast Pacific.
Fin whale.............................. California/Oregon/Washington.
Sei whale.............................. Eastern North Pacific.
Minke whale............................ Alaska.
Minke whale............................ California/Oregon/Washington.
Humpback whale......................... Central North Pacific.
Humpback whale......................... California/Oregon/Washington.
Gray whale............................. Eastern North Pacific.
Bottlenose dolphin..................... California/Oregon/Washington
Offshore.
Killer whale........................... Alaska Resident.
Killer whale........................... Eastern North Pacific Offshore.
Killer whale........................... West Coast Transient.
Killer whale........................... Southern Resident.
Northern right whale dolphin........... California/Oregon/Washington.
Pacific white-sided dolphin............ North Pacific.
Pacific white-sided dolphin............ California/Oregon/Washington.
Risso's dolphin........................ California/Oregon/Washington.
Short-beaked common dolphin............ California/Oregon/Washington.
Short-finned pilot whale............... California/Oregon/Washington.
Striped dolphin........................ California/Oregon/Washington.
Pygmy sperm whale...................... California/Oregon/Washington.
Dwarf sperm whale...................... California/Oregon/Washington.
Dall's porpoise........................ Alaska.
Dall's porpoise........................ California/Oregon/Washington.
Harbor porpoise........................ Southeast Alaska.
Harbor porpoise........................ Northern Oregon & Washington
Coast.
Harbor porpoise........................ Northern California/Southern
Oregon.
Harbor porpoise........................ Washington Inland Waters.
Sperm whale............................ California/Oregon/Washington.
Baird's beaked whale................... California/Oregon/Washington.
Cuvier's beaked whale.................. California/Oregon/Washington.
Mesoplodon species..................... California/Oregon/Washington.
California sea lion.................... U.S. Stock.
Steller sea lion....................... Eastern U.S.
Guadalupe fur seal..................... Mexico.
Northern fur seal...................... Eastern Pacific.
Northern fur seal...................... California.
Harbor seal............................ Southeast Alaska--Clarence
Strait.
Harbor seal............................ Oregon & Washington Coastal.
Harbor seal............................ Washington Northern Inland
Waters.
Harbor seal............................ Hood Canal.
Harbor seal............................ Southern Puget Sound.
Northern elephant seal................. California.
------------------------------------------------------------------------

Sec. 218.143 Prohibitions.

Notwithstanding incidental takings contemplated in Sec. 218.142(a)
and authorized by LOAs issued under Sec. Sec. 216.106 of this chapter
and 218.146, no person in connection with the activities listed in
Sec. 218.140(c) may:
(a) Violate, or fail to comply with, the terms, conditions, and
requirements of this subpart or an LOA issued under Sec. Sec. 216.106
of this chapter and 218.146;
(b) Take any marine mammal not specified in Sec. 218.142(b);
(c) Take any marine mammal specified in Sec. 218.142(b) in any
manner other than as specified in the LOAs; or
(d) Take a marine mammal specified in Sec. 218.142(b) if NMFS
determines such taking results in more than a negligible impact on the
species or stocks of such marine mammal.

Sec. 218.144 Mitigation requirements.

When conducting the activities identified in Sec. 218.140(c), the
mitigation measures contained in any LOAs issued under Sec. Sec.
216.106 of this chapter and 218.146 must be implemented. These
mitigation measures include, but are not limited to:
(a) Procedural mitigation. Procedural mitigation is mitigation that
the Navy must implement whenever and wherever an applicable training or
testing activity takes place within the NWTT Study Area for acoustic
stressors (i.e., active sonar, weapons firing noise), explosive
stressors (i.e., sonobuoys, torpedoes, medium-caliber and large-caliber
projectiles, missiles, bombs, mine countermeasure and neutralization
activities, mine neutralization involving Navy divers), and physical
disturbance and strike stressors (i.e., vessel movement, towed in-water
devices, small-, medium-, and large-caliber non-explosive practice
munitions, non-explosive missiles, non-explosive bombs and mine
shapes).
(1) Environmental awareness and education. Appropriate Navy
personnel (including civilian personnel) involved in mitigation and
training or testing activity reporting under the specified activities
will complete one or more modules of the U.S Navy Afloat Environmental
Compliance Training Series, as identified in their career path training
plan. Modules include: Introduction to the U.S. Navy Afloat
Environmental Compliance Training Series; Marine Species Awareness
Training; U.S. Navy Protective Measures Assessment Protocol; and U.S.
Navy Sonar Positional Reporting System and Marine Mammal Incident
Reporting.

[[Page 34041]]

(2) Active sonar. Active sonar includes low-frequency active sonar,
mid-frequency active sonar, and high-frequency active sonar. For
vessel-based activities, mitigation applies only to sources that are
positively controlled and deployed from manned surface vessels (e.g.,
sonar sources towed from manned surface platforms). For aircraft-based
activities, mitigation applies only to sources that are positively
controlled and deployed from manned aircraft that do not operate at
high altitudes (e.g., rotary-wing aircraft). Mitigation does not apply
to active sonar sources deployed from unmanned aircraft or aircraft
operating at high altitudes (e.g., maritime patrol aircraft).
(i) Number of Lookouts and observation platform--(A) For hull-
mounted sources, one Lookout for platforms with space or manning
restrictions while underway (at the forward part of a small boat or
ship) and platforms using active sonar while moored or at anchor
(including pierside); and two Lookouts for platforms without space or
manning restrictions while underway (at the forward part of the ship).
(B) For sources that are not hull mounted, One Lookout on the ship
or aircraft conducting the activity.
(ii) Mitigation zone and requirements. (A) Prior to the initial
start of the activity (e.g., when maneuvering on station), Navy
personnel must observe the mitigation zone for floating vegetation and
marine mammals; if floating vegetation or a marine mammals is observed,
Navy personnel must relocate or delay the start of active sonar
transmission until the mitigation zone is clear of floating vegetation
or until the conditions in paragraph (a)(2)(ii)(D) of this section are
met for marine mammals.
(B) During the activity, for low-frequency active sonar at or above
200 dB and hull-mounted mid-frequency active sonar, Navy personnel must
observe the mitigation zone for marine mammals. If a marine mammal is
observed within 1,000 yd of the sonar source, Navy personnel must power
down active sonar transmission by 6 dB. If a marine mammal is observed
within 500 yd of the sonar source, Navy personnel must power down
active sonar transmission an additional 4 dB (10 dB total). Navy
personnel must cease transmission if a cetacean or pinniped in the NWTT
Offshore Area or Western Behm Canal is observed within 200 yd of the
active sonar source and must cease transmission if a pinniped in NWTT
Inland Waters is observed within 100 yd of the active sonar source
(except if hauled out on, or in the water near, man-made structures and
vessels).
(C) During the activity, for low-frequency active sonar below 200
dB, mid-frequency active sonar sources that are not hull-mounted, and
high-frequency sonar, Navy personnel must observe the mitigation zone
for marine mammals. Navy personnel must cease transmission if a
cetacean in the NWTT Offshore Area, NWTT Inshore Area, or Western Behm
Canal is observed within 200 yd of the sonar source. Navy personnel
must cease transmission if a pinniped in the NWTT Offshore Area or
Western Behm Canal is observed within 200 yd of the sonar source and
must cease transmission if a pinniped in NWTT Inland Waters is observed
within 100 yd of the active sonar source (except if hauled out on, or
in the water near, man-made structures and vessels).
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing or powering up active sonar transmission) until
one of the following conditions has been met: The animal is observed
exiting the mitigation zone; the animal is thought to have exited the
mitigation zone based on a determination of its course, speed, and
movement relative to the sonar source; the mitigation zone has been
clear from any additional sightings for 10 minutes (min) for aircraft-
deployed sonar sources or 30 min for vessel-deployed sonar sources; for
mobile activities, the active sonar source has transited a distance
equal to double that of the mitigation zone size beyond the location of
the last sighting; or for activities using hull-mounted sonar where a
dolphin(s) is observed in the mitigation zone, the Lookout concludes
that the dolphin(s) is deliberately closing in on the ship to ride the
ship's bow wave, and are therefore out of the main transmission axis of
the sonar (and there are no other marine mammal sightings within the
mitigation zone).
(3) Weapons firing noise. Weapons firing noise associated with
large-caliber gunnery activities.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned on the ship conducting the firing. Depending on the
activity, the Lookout could be the same as the one provided for under
``Explosive medium-caliber and large-caliber projectiles'' or under
``Small-, medium-, and large-caliber non-explosive practice munitions''
in paragraphs (a)(6)(i) and (a)(13)(i) of this section.
(ii) Mitigation zone and requirements. (A) Thirty degrees on either
side of the firing line out to 70 yd from the muzzle of the weapon
being fired.
(B) Prior to the initial start of the activity, Navy personnel must
observe the mitigation zone for floating vegetation and marine mammals;
if floating vegetation or a marine mammal is observed, Navy personnel
must relocate or delay the start of weapons firing until the mitigation
zone is clear of floating vegetation or until the conditions in
paragraph (a)(3)(ii)(D) of this section are met for marine mammals.
(C) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease weapons firing.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing weapons firing) until one of the following
conditions has been met: The animal is observed exiting the mitigation
zone; the animal is thought to have exited the mitigation zone based on
a determination of its course, speed, and movement relative to the
firing ship; the mitigation zone has been clear from any additional
sightings for 30 min; or for mobile activities, the firing ship has
transited a distance equal to double that of the mitigation zone size
beyond the location of the last sighting.
(4) Explosive sonobuoys--(i) Number of Lookouts and observation
platform. One Lookout must be positioned in an aircraft or on a small
boat. If additional platforms are participating in the activity, Navy
personnel positioned in those assets (e.g., safety observers,
evaluators) must support observing the mitigation zone for applicable
biological resources while performing their regular duties.
(ii) Mitigation zone and requirements. (A) 600 yd around an
explosive sonobuoy.
(B) Prior to the initial start of the activity (e.g., during
deployment of a sonobuoy field, which typically lasts 20-30 min), Navy
personnel must conduct passive acoustic monitoring for marine mammals
and use information from detections to assist visual observations. Navy
personnel also must visually observe the mitigation zone for floating
vegetation and marine mammals; if floating vegetation or a

[[Page 34042]]

marine mammal is observed, Navy personnel must relocate or delay the
start of sonobuoy or source/receiver pair detonations until the
mitigation zone is clear of floating vegetation or until the conditions
in paragraph (a)(4)(ii)(D) of this section are met for marine mammals.
(C) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease sonobuoy or source/receiver pair detonations.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing detonations) until one of the following conditions
has been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
sonobuoy; or the mitigation zone has been clear from any additional
sightings for 10 min when the activity involves aircraft that have fuel
constraints, or 30 min when the activity involves aircraft that are not
typically fuel constrained.
(E) After completion of the activity (e.g., prior to maneuvering
off station), Navy personnel must, when practical (e.g., when platforms
are not constrained by fuel restrictions or mission-essential follow-on
commitments), observe for marine mammals in the vicinity of where
detonations occurred; if any injured or dead marine mammals are
observed, Navy personnel must follow established incident reporting
procedures. If additional platforms are supporting this activity (e.g.,
providing range clearance), these Navy assets must assist in the visual
observation of the area where detonations occurred.
(5) Explosive torpedoes--(i) Number of Lookouts and observation
platform. One Lookout must be positioned in an aircraft. If additional
platforms are participating in the activity, Navy personnel positioned
in those assets (e.g., safety observers, evaluators) must support
observing the mitigation zone for marine mammals while performing their
regular duties.
(ii) Mitigation zone and requirements. (A) 2,100 yd around the
intended impact location.
(B) Prior to the initial start of the activity (e.g., during
deployment of the target), Navy personnel must conduct passive acoustic
monitoring for marine mammals and use the information from detections
to assist visual observations. Navy personnel also must visually
observe the mitigation zone for floating vegetation and marine mammals;
if floating vegetation or a marine mammal is observed, Navy personnel
must relocate or delay the start of firing until the mitigation zone is
clear of floating vegetation or until the conditions in paragraph
(a)(5)(ii)(D) of this section are met for marine mammals.
(C) During the activity, Navy personnel must observe the mitigation
zone for marine mammals. If a marine mammal is observed, Navy personnel
must cease firing.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing firing) until one of the following conditions has
been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
intended impact location; or the mitigation zone has been clear from
any additional sightings for 10 min when the activity involves aircraft
that have fuel constraints, or 30 min when the activity involves
aircraft that are not typically fuel constrained.
(E) After completion of the activity (e.g., prior to maneuvering
off station), Navy personnel must, when practical (e.g., when platforms
are not constrained by fuel restrictions or mission-essential follow-on
commitments), observe for marine mammals in the vicinity of where
detonations occurred; if any injured or dead marine mammals are
observed, Navy personnel must follow established incident reporting
procedures. If additional platforms are supporting this activity (e.g.,
providing range clearance), these Navy assets must assist in the visual
observation of the area where detonations occurred.
(6) Explosive medium-caliber and large-caliber projectiles. Gunnery
activities using explosive medium-caliber and large-caliber
projectiles. Mitigation applies to activities using a surface target.
(i) Number of Lookouts and observation platform. One Lookout must
be on the vessel conducting the activity. For activities using
explosive large-caliber projectiles, depending on the activity, the
Lookout could be the same as the one described in ``Weapons firing
noise'' in paragraph (a)(3)(i) of this section. If additional platforms
are participating in the activity, Navy personnel positioned in those
assets (e.g., safety observers, evaluators) must support observing the
mitigation zone for marine mammals while performing their regular
duties.
(ii) Mitigation zone and requirements. (A) 600 yd around the
intended impact location for explosive medium-caliber projectiles.
(B) 1,000 yd around the intended impact location for explosive
large-caliber projectiles.
(C) Prior to the initial start of the activity (e.g., when
maneuvering on station), Navy personnel must observe the mitigation
zone for floating vegetation and marine mammals; if floating vegetation
or a marine mammal is observed, Navy personnel must relocate or delay
the start of firing until the mitigation zone is clear of floating
vegetation or until the conditions in paragraph (a)(6)(ii)(E) are met
for marine mammals.
(D) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if a marine mammal is observed, Navy personnel
must cease firing.
(E) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing firing) until one of the following conditions has
been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
intended impact location; the mitigation zone has been clear from any
additional sightings for 30 min for vessel-based firing; or, for
activities using mobile targets, the intended impact location has
transited a distance equal to double that of the mitigation zone size
beyond the location of the last sighting.
(F) After completion of the activity (e.g., prior to maneuvering
off station), Navy personnel must, when practical (e.g., when platforms
are not constrained by fuel restrictions or mission-essential follow-on
commitments), observe for marine mammals in the vicinity of where
detonations occurred; if any injured or dead marine mammals are
observed, Navy personnel must follow established incident reporting
procedures. If additional platforms are supporting this activity (e.g.,
providing range clearance),

[[Page 34043]]

these Navy assets must assist in the visual observation of the area
where detonations occurred.
(7) Explosive missiles. Aircraft-deployed explosive missiles.
Mitigation applies to activities using a surface target.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned in an aircraft. If additional platforms are participating
in the activity, Navy personnel positioned in those assets (e.g.,
safety observers, evaluators) must support observing the mitigation
zone for marine mammals while performing their regular duties.
(ii) Mitigation zone and requirements. (A) 2,000 yd around the
intended impact location.
(B) Prior to the initial start of the activity (e.g., during a fly-
over of the mitigation zone), Navy personnel must observe the
mitigation zone for floating vegetation and marine mammals; if floating
vegetation or a marine mammal is observed, Navy personnel must relocate
or delay the start of firing until the mitigation zone is clear of
floating vegetation or until the conditions in paragraph (a)(7)(ii)(D)
are met for marine mammals.
(C) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease firing.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing firing) until one of the following conditions has
been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
intended impact location; or the mitigation zone has been clear from
any additional sightings for 10 min when the activity involves aircraft
that have fuel constraints, or 30 min when the activity involves
aircraft that are not typically fuel constrained.
(E) After completion of the activity (e.g., prior to maneuvering
off station), Navy personnel must, when practical (e.g., when platforms
are not constrained by fuel restrictions or mission-essential follow-on
commitments), observe for marine mammals in the vicinity of where
detonations occurred; if any injured or dead marine mammals are
observed, Navy personnel must follow established incident reporting
procedures. If additional platforms are supporting this activity (e.g.,
providing range clearance), these Navy assets must assist in the visual
observation of the area where detonations occurred.
(8) Explosive bombs--(i) Number of Lookouts and observation
platform. One Lookout must be positioned in an aircraft conducting the
activity. If additional platforms are participating in the activity,
Navy personnel positioned in those assets (e.g., safety observers,
evaluators) must support observing the mitigation zone for marine
mammals while performing their regular duties.
(ii) Mitigation zone and requirements. (A) 2,500 yd around the
intended target.
(B) Prior to the initial start of the activity (e.g., when arriving
on station), Navy personnel must observe the mitigation zone for
floating vegetation and marine mammals; if floating vegetation or a
marine mammals is observed, Navy personnel must relocate or delay the
start of bomb deployment until the mitigation zone is clear of floating
vegetation or until the conditions in paragraph (a)(8)(ii)(D) of this
section are met for marine mammals.
(C) During the activity (e.g., during target approach), Navy
personnel must observe the mitigation zone for marine mammals; if a
marine mammal is observed, Navy personnel must cease bomb deployment.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing bomb deployment) until one of the following
conditions has been met: The animal is observed exiting the mitigation
zone; the animal is thought to have exited the mitigation zone based on
a determination of its course, speed, and movement relative to the
intended target; the mitigation zone has been clear from any additional
sightings for 10 min; or for activities using mobile targets, the
intended target has transited a distance equal to double that of the
mitigation zone size beyond the location of the last sighting.
(E) After completion of the activity (e.g., prior to maneuvering
off station), Navy personnel must, when practical (e.g., when platforms
are not constrained by fuel restrictions or mission-essential follow-on
commitments), observe for marine mammals in the vicinity of where
detonations occurred; if any injured or dead marine mammals are
observed, Navy personnel must follow established incident reporting
procedures. If additional platforms are supporting this activity (e.g.,
providing range clearance), these Navy assets must assist in the visual
observation of the area where detonations occurred.
(9) Explosive mine countermeasure and neutralization activities--
(i) Number of Lookouts and observation platform. (A) One Lookout must
be positioned on a vessel or in an aircraft when implementing the
smaller mitigation zone.
(B) Two Lookouts must be positioned (one in an aircraft and one on
a small boat) when implementing the larger mitigation zone.
(C) If additional platforms are participating in the activity, Navy
personnel positioned in those assets (e.g., safety observers,
evaluators) must support observing the mitigation zone for marine
mammals while performing their regular duties.
(ii) Mitigation zone and requirements. (A) 600 yd around the
detonation site for activities using <=5 lb net explosive weight.
(B) 2,100 yd around the detonation site for activities using >5-60
lb net explosive weight.
(C) Prior to the initial start of the activity (e.g., when
maneuvering on station; typically, 10 min when the activity involves
aircraft that have fuel constraints, or 30 min when the activity
involves aircraft that are not typically fuel constrained), Navy
personnel must observe the mitigation zone for floating vegetation and
marine mammals; if floating vegetation or a marine mammal is observed,
Navy personnel must relocate or delay the start of detonations until
the mitigation zone is clear of floating vegetation or until the
conditions in paragraph (ii)(E) are met for marine mammals.
(D) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if a marine mammal is observed, Navy personnel
must cease detonations.
(E) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing detonations) until one of the following conditions
has been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to detonation
site; or the mitigation zone has been clear from

[[Page 34044]]

any additional sightings for 10 min when the activity involves aircraft
that have fuel constraints, or 30 min when the activity involves
aircraft that are not typically fuel constrained.
(F) After completion of the activity (typically 10 min when the
activity involves aircraft that have fuel constraints, or 30 min when
the activity involves aircraft that are not typically fuel
constrained), Navy personnel must observe for marine mammals in the
vicinity of where detonations occurred; if any injured or dead marine
mammals are observed, Navy personnel must follow established incident
reporting procedures. If additional platforms are supporting this
activity (e.g., providing range clearance), these Navy assets must
assist in the visual observation of the area where detonations
occurred.
(10) Explosive mine neutralization activities involving Navy
divers--(i) Number of Lookouts and observation platform. (A) Two
Lookouts (two small boats with one Lookout each (one of which must be a
Navy biologist)).
(B) All divers placing the charges on mines must support the
Lookouts while performing their regular duties and will report
applicable sightings to their supporting small boat or Range Safety
Officer.
(C) If additional platforms are participating in the activity, Navy
personnel positioned in those assets (e.g., safety observers,
evaluators) must support observing the mitigation zone for marine
mammals while performing their regular duties.
(ii) Mitigation zone and requirements. (A) 500 yd around the
detonation site during activities using >0.5-2.5 lb net explosive
weight.
(B) Prior to the initial start of the activity (e.g., starting 30
min before the first planned detonation), Navy personnel must observe
the mitigation zone for floating vegetation and marine mammals; if
floating vegetation is observed, Navy personnel must relocate or delay
the start of detonations until the mitigation zone is clear of floating
vegetation. If a marine mammal is observed, Navy personnel must ensure
the area is clear of marine mammals for 30 min prior to commencing a
detonation. A Navy biologist must serve as the lead Lookout and must
make the final determination that the mitigation zone is clear of any
floating vegetation or marine mammals prior to the commencement of a
detonation. The Navy biologist must maintain radio communication with
the unit conducting the event and the other Lookout.
(C) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if a marine mammal is observed, Navy personnel
must cease detonations. To the maximum extent practicable depending on
mission requirements, safety, and environmental conditions, Navy
personnel must position boats near the midpoint of the mitigation zone
radius (but outside of the detonation plume and human safety zone),
must position themselves on opposite sides of the detonation location
(when two boats are used), and must travel in a circular pattern around
the detonation location with one Lookout observing inward toward the
detonation site and the other observing outward toward the perimeter of
the mitigation zone. Navy personnel must only use positively controlled
charges (i.e., no time-delay fuses). Navy personnel must use the
smallest practicable charge size for each activity. All activities must
be conducted in Beaufort sea state number 2 conditions or better and
must not be conducted in low visibility conditions.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted animal to leave the mitigation zone prior to the initial start
of the activity (by delaying the start) or during the activity (by not
recommencing detonations) until one of the following conditions has
been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
detonation site; or the mitigation zone has been clear from any
additional sightings for 30 min.
(E) After each detonation and completion of an activity the Navy
must observe for marine mammals for 30 min Navy personnel must observe
for marine mammals in the vicinity of where detonations occurred and
immediately downstream of the detonation location; if any injured or
dead marine mammals are observed, Navy personnel must follow
established incident reporting procedures. If additional platforms are
supporting this activity (e.g., providing range clearance), these Navy
assets must assist in the visual observation of the area where
detonations occurred.
(F) At the Hood Canal Explosive Ordnance Disposal Range and
Crescent Harbor Explosive Ordnance Disposal Range, Navy personnel must
obtain permission from the appropriate designated Command authority
prior to conducting explosive mine neutralization activities involving
the use of Navy divers.
(G) At the Hood Canal Explosive Ordnance Disposal Range, during
February, March, and April (the juvenile migration period for Hood
Canal Summer Run Chum), Navy personnel must not use explosives in bin
E3 (>0.5-2.5 lb net explosive weight), and must instead use explosives
in bin E0 (<0.1 lb net explosive weight).
(H) At the Hood Canal Explosive Ordnance Disposal Range, during
August, September, and October (the adult migration period for Hood
Canal summer-run chum and Puget Sound Chinook), Navy personnel must
avoid the use of explosives in bin E3 (>0.5-2.5 lb net explosive
weight), and must instead use explosive bin E0 (<0.1 lb net explosive
weight) to the maximum extent practicable unless necessitated by
mission requirements.
(I) At the Crescent Harbor Explosive Ordnance Disposal Range, Navy
personnel must conduct explosive activities at least 1,000 meters (m)
from the closest point of land to avoid or reduce impacts on fish
(e.g., bull trout) in nearshore habitat areas.
(11) Vessel movement. The mitigation will not be applied if: The
vessel's safety is threatened; the vessel is restricted in its ability
to maneuver (e.g., during launching and recovery of aircraft or landing
craft, during towing activities, when mooring, during Transit
Protection Program exercises, and other events involving escort
vessels); the vessel is operated autonomously; or when impractical
based on mission requirements (e.g., during test body retrieval by
range craft).
(i) Number of Lookouts and observation platform. One Lookout must
be on the vessel that is underway.
(ii) Mitigation zone and requirements. (A) 500 yd around whales for
surface vessels other than small boats.
(B) 200 yd around all marine mammals other than whales (except bow-
riding dolphins and pinnipeds hauled out on man-made navigational
structures, port structures, and vessels) for surface vessels other
than small boats.
(C) 100 yd around marine mammals (except bow-riding dolphins and
pinnipeds hauled out on man-made navigational structures, port
structures, and vessels) for small boats, such as range craft.
(D) During the activity (when underway), Navy personnel must
observe the mitigation zone for marine mammals; if a marine mammal is
observed, Navy personnel must maneuver to maintain distance.
(E) Prior to Small Boat Attack exercises at Naval Station Everett,
Naval Base Kitsap Bangor, or Naval Base

[[Page 34045]]

Kitsap Bremerton, Navy event planners must coordinate with Navy
biologists during the event planning process. Navy biologists must work
with NMFS to determine the likelihood of marine mammal presence in the
planned training location. Navy biologists must notify event planners
of the likelihood of species presence as they plan specific details of
the event (e.g., timing, location, duration). Navy personnel must
provide additional environmental awareness training to event
participants. The training must alert participating ship crews to the
possible presence of marine mammals in the training location. Lookouts
must use the information to assist their visual observation of
applicable mitigation zones and to aid in the implementation of
procedural mitigation.
(iii) Incident reporting procedures. If a marine mammal vessel
strike occurs, Navy personnel must follow the established incident
reporting procedures.
(12) Towed in-water devices. Mitigation applies to devices that are
towed from a manned surface platform or manned aircraft, or when a
manned support craft is already participating in an activity involving
in-water devices being towed by unmanned platforms. The mitigation will
not be applied if the safety of the towing platform or in-water device
is threatened.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned on a manned towing platform or support craft.
(ii) Mitigation zone and requirements. (A) 250 yd around marine
mammals (except bow-riding dolphins and pinnipeds hauled out on man-
made navigational structures, port structures, and vessels) for in-
water devices towed by aircraft or surface vessels other than small
boats.
(B) 100 yd around marine mammals (except bow-riding dolphins and
pinnipeds hauled out on man-made navigational structures, port
structures, and vessels) for in-water devices towed by small boats,
such as range craft.
(C) During the activity (i.e., when towing an in-water device),
Navy personnel must observe the mitigation zone for marine mammals; if
a marine mammal is observed, Navy personnel must maneuver to maintain
distance.
(13) Small-, medium-, and large-caliber non-explosive practice
munitions. Gunnery activities using small-, medium-, and large-caliber
non-explosive practice munitions. Mitigation applies to activities
using a surface target.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned on the platform conducting the activity. Depending on the
activity, the Lookout could be the same as the one described for
``Weapons firing noise'' in paragraph (a)(3)(i) of this section.
(ii) Mitigation zone and requirements. (A) 200 yd around the
intended impact location.
(B) Prior to the initial start of the activity (e.g., when
maneuvering on station), Navy personnel must observe the mitigation
zone for floating vegetation and marine mammals; if floating vegetation
or a marine mammal is observed, Navy personnel must relocate or delay
the start until the mitigation zone is clear of floating vegetation or
until the conditions in paragraph (a)(13)(ii)(D) of this section are
met for marine mammals.
(C) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if a marine mammal is observed, Navy personnel
must cease firing.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing firing) until one of the following conditions has
been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
intended impact location; the mitigation zone has been clear from any
additional sightings for 10 min for aircraft-based firing or 30 min for
vessel-based firing; or for activities using a mobile target, the
intended impact location has transited a distance equal to double that
of the mitigation zone size beyond the location of the last sighting.
(14) Non-explosive missiles. Aircraft-deployed non-explosive
missiles. Mitigation applies to activities using a surface target.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned in an aircraft.
(ii) Mitigation zone and requirements. (A) 900 yd around the
intended impact location.
(B) Prior to the initial start of the activity (e.g., during a fly-
over of the mitigation zone), Navy personnel must observe the
mitigation zone for floating vegetation and marine mammals; if floating
vegetation or a marine mammal is observed, Navy personnel must relocate
or delay the start of firing until the mitigation zone is clear of
floating vegetation or until the conditions in paragraph (a)(14)(ii)(D)
of this section are met for marine mammals.
(C) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if a marine mammal is observed, Navy personnel
must cease firing.
(D) Commencement/recommencement conditions after a marine mammal
sighting prior to or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing firing) until one of the following conditions has
been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
intended impact location; or the mitigation zone has been clear from
any additional sightings for 10 min when the activity involves aircraft
that have fuel constraints, or 30 min when the activity involves
aircraft that are not typically fuel constrained.
(15) Non-explosive bombs and mine shapes. Non-explosive bombs and
non-explosive mine shapes during mine laying activities.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned in an aircraft.
(ii) Mitigation zone and requirements. (A) 1,000 yd around the
intended target.
(B) Prior to the initial start of the activity (e.g., when arriving
on station), Navy personnel must observe the mitigation zone for
floating vegetation and marine mammals; if floating vegetation or a
marine mammal is observed, Navy personnel must relocate or delay the
start of bomb deployment or mine laying until the mitigation zone is
clear of floating vegetation or until the conditions in paragraph
(a)(15)(ii)(D) of section are met for marine mammals.
(C) During the activity (e.g., during approach of the target or
intended minefield location), Navy personnel must observe the
mitigation zone for marine mammals and, if a marine mammal is observed,
Navy personnel must cease bomb deployment or mine laying.
(D) Commencement/recommencement conditions after a marine mammal
sighting prior to or during the activity. Navy personnel must allow a
sighted marine mammal to leave the mitigation zone prior to the initial
start of the activity (by delaying the start) or during the activity
(by not recommencing bomb deployment or mine laying) until one of the
following conditions has been met:

[[Page 34046]]

The animal is observed exiting the mitigation zone; the animal is
thought to have exited the mitigation zone based on a determination of
its course, speed, and movement relative to the intended target or
minefield location; the mitigation zone has been clear from any
additional sightings for 10 min; or for activities using mobile
targets, the intended target has transited a distance equal to double
that of the mitigation zone size beyond the location of the last
sighting.
(b) Mitigation areas. In addition to procedural mitigation, Navy
personnel must implement mitigation measures within mitigation areas to
avoid or reduce potential impacts on marine mammals.
(1) Mitigation areas for marine mammals for NWTT Study Area for
sonar, explosives, and physical disturbance and vessel strikes--(i)
Mitigation area requirements--(A) Marine Species Coastal Mitigation
Area (year round). (1) Within 50 nmi from shore in the Marine Species
Coastal Mitigation Area, Navy personnel must not conduct: Explosive
training activities; explosive testing activities (with the exception
of explosive Mine Countermeasure and Neutralization Testing
activities); and non-explosive missile training activities. Should
national security require conducting these activities in the mitigation
area, Navy personnel must obtain permission from the appropriate
designated Command authority prior to commencement of the activity.
Navy personnel must provide NMFS with advance notification and include
information about the event in its annual activity reports to NMFS.
(2) Within 20 nmi from shore in the Marine Species Coastal
Mitigation Area, Navy personnel must not conduct non-explosive large-
caliber gunnery training activities and non-explosive bombing training
activities. Should national security require conducting these
activities in the mitigation area, Navy personnel must obtain
permission from the appropriate designated Command authority prior to
commencement of the activity. Navy personnel must provide NMFS with
advance notification and include information about the event in its
annual activity reports to NMFS.
(3) Within 12 nmi from shore in the Marine Species Coastal
Mitigation Area, Navy personnel must not conduct: Non-explosive small-
and medium-caliber gunnery training activities; non-explosive torpedo
training activities; and Anti-Submarine Warfare Tracking Exercise--
Helicopter, Maritime Patrol Aircraft, Ship, or Submarine training
activities. Should national security require conducting these
activities in the mitigation area, Navy personnel must obtain
permission from the appropriate designated Command authority prior to
commencement of the activity. Navy personnel must provide NMFS with
advance notification and include information about the event in its
annual activity reports to NMFS.
(B) Olympic Coast National Marine Sanctuary Mitigation Area (year-
round). (1) Within the Olympic Coast National Marine Sanctuary
Mitigation Area, Navy personnel must not conduct more than 32 hours of
MF1 mid-frequency active sonar during training annually and will not
conduct non-explosive bombing training activities. Should national
security require conducting more than 32 hours of MF1 mid-frequency
active sonar during training annually or conducting non-explosive
bombing training activities in the mitigation area, Navy personnel must
obtain permission from the appropriate designated Command authority
prior to commencement of the activity. Navy personnel must provide NMFS
with advance notification and include information about the event in
its annual activity reports to NMFS.
(2) Within the Olympic Coast National Marine Sanctuary Mitigation
Area, Navy personnel must not conduct more than 33 hours of MF1 mid-
frequency active sonar during testing annually (except within the
portion of the mitigation area that overlaps the Quinault Range Site)
and must not conduct explosive Mine Countermeasure and Neutralization
Testing activities. Should national security require conducting more
than 33 hours of MF1 mid-frequency active sonar during testing annually
(except within the portion of the mitigation area that overlaps the
Quinault Range Site) or conducting explosive Mine Countermeasure and
Neutralization Testing activities in the mitigation area, Navy
personnel must obtain permission from the appropriate designated
Command authority prior to commencement of the activity. Navy personnel
must provide NMFS with advance notification and include information
about the event in its annual activity reports to NMFS.
(C) Stonewall and Heceta Bank Humpback Whale Mitigation Area (May
1-November 30). Within the Stonewall and Heceta Bank Humpback Whale
Mitigation Area, Navy personnel must not use MF1 mid-frequency active
sonar or explosives during training and testing from May 1 to November
30. Should national security require using MF1 mid-frequency active
sonar or explosives during training and testing from May 1 to November
30, Navy personnel must obtain permission from the appropriate
designated Command authority prior to commencement of the activity.
Navy personnel must provide NMFS with advance notification and include
information about the event in its annual activity reports to NMFS.
(D) Point St. George Humpback Whale Mitigation Area (July 1-
November 30). Within the Point St. George Humpback Whale Mitigation
Area, Navy personnel must not use MF1 mid-frequency active sonar or
explosives during training and testing from July 1 to November 30.
Should national security require using MF1 mid-frequency active sonar
or explosives during training and testing from July 1 to November 30,
Navy personnel must obtain permission from the appropriate designated
Command authority prior to commencement of the activity. Navy personnel
must provide NMFS with advance notification and include information
about the event in its annual activity reports to NMFS.
(E) Puget Sound and Strait of Juan de Fuca Mitigation Area (year-
round). (1) Within the Puget Sound and Strait of Juan de Fuca
Mitigation Area, Navy personnel must obtain approval from the
appropriate designated Command authority prior to: The use of hull-
mounted mid-frequency active sonar during training while underway or
conducting ship and submarine active sonar pierside maintenance or
testing.
(2) Within the Puget Sound and Strait of Juan de Fuca Mitigation
Area for Civilian Port Defense--Homeland Security Anti-Terrorism/Force
Protection Exercises, Navy personnel must coordinate with Navy
biologists during the event planning process. Navy biologists must work
with NMFS to determine the likelihood of gray whale and Southern
Resident Killer Whale presence in the planned training location. Navy
biologists must notify Navy event planners of the likelihood of species
presence as they plan specific details of the event (e.g., timing,
location, duration). Navy personnel must ensure environmental awareness
of event participants. Environmental awareness will help alert
participating ship and aircraft crews to the possible presence of
marine mammals in the training location, such as gray whales and
Southern Resident Killer Whales.
(F) Northern Puget Sound Gray Whale Mitigation Area (March 1-May
31). Within the Northern Puget Sound Gray Whale Mitigation Area, Navy
personnel must not conduct Civilian Port Defense--Homeland Security
Anti-Terrorism/Force Protection Exercises from March 1 to May 31.
Should national security require conducting

[[Page 34047]]

Civilian Port Defense--Homeland Security Anti-Terrorism/Force
Protection Exercises from March 1 to May 31, Navy personnel must obtain
permission from the appropriate designated Command authority prior to
commencement of the activity. Navy personnel must provide NMFS with
advance notification and include information about the event in its
annual activity reports to NMFS.
(ii) [Reserved]

Sec. 218.145 Requirements for monitoring and reporting.

(a) Unauthorized take. Navy personnel must notify NMFS immediately
(or as soon as operational security considerations allow) if the
specified activity identified in Sec. 218.140 is thought to have
resulted in the mortality or serious injury of any marine mammals, or
in any Level A harassment or Level B harassment of marine mammals not
identified in this subpart.
(b) Monitoring and reporting under the LOAs. The Navy must conduct
all monitoring and reporting required under the LOAs, including abiding
by the U.S. Navy's Marine Species Monitoring Program. Details on
program goals, objectives, project selection process, and current
projects are available at www.navymarinespeciesmonitoring.us.
(c) Notification of injured, live stranded, or dead marine mammals.
The Navy must consult the Notification and Reporting Plan, which sets
out notification, reporting, and other requirements when dead, injured,
or live stranded marine mammals are detected. The Notification and
Reporting Plan is available at https://www.fisheries.noaa.gov/national/
marine-mammal-protection/incidental-take-authorizations-military-
readiness-activities.
(d) Annual NWTT Study Area marine species monitoring report. The
Navy must submit an annual report of the NWTT Study Area monitoring
describing the implementation and results from the previous calendar
year. Data collection methods must be standardized across range
complexes and study areas to allow for comparison in different
geographic locations. The report must be submitted to the Director,
Office of Protected Resources, NMFS, either within three months after
the end of the calendar year, or within three months after the
conclusion of the monitoring year, to be determined by the Adaptive
Management process. NMFS will submit comments or questions on the
report, if any, within one month of receipt. The report will be
considered final after the Navy has addressed NMFS' comments, or one
month after submittal of the draft if NMFS does not provide comments on
the draft report. This report will describe progress of knowledge made
with respect to intermediate scientific objectives within the NWTT
Study Area associated with the Integrated Comprehensive Monitoring
Program (ICMP). Similar study questions must be treated together so
that progress on each topic can be summarized across all Navy ranges.
The report need not include analyses and content that does not provide
direct assessment of cumulative progress on the monitoring plan study
questions. As an alternative, the Navy may submit a multi-range complex
annual monitoring plan report to fulfill this requirement. Such a
report will describe progress of knowledge made with respect to
monitoring study questions across multiple Navy ranges associated with
the ICMP. Similar study questions must be treated together so that
progress on each topic can be summarized across multiple Navy ranges.
The report need not include analyses and content that does not provide
direct assessment of cumulative progress on the monitoring study
question. This will continue to allow the Navy to provide a cohesive
monitoring report covering multiple ranges (as per ICMP goals), rather
than entirely separate reports for the NWTT, Hawaii-Southern
California, Gulf of Alaska, and Mariana Islands Study Areas.
(e) Annual NWTT Study Area training exercise report and testing
activity reports. Each year, the Navy must submit two preliminary
reports (Quick Look Report) detailing the status of applicable sound
sources within 21 days after the anniversary of the date of issuance of
each LOA to the Director, Office of Protected Resources, NMFS. Each
year, the Navy must submit a detailed report to the Director, Office of
Protected Resources, NMFS, within three months after the one-year
anniversary of the date of issuance of the LOA. NMFS will submit
comments or questions on the report, if any, within one month of
receipt. The report will be considered final after the Navy has
addressed NMFS' comments, or one month after submittal of the draft if
NMFS does not provide comments on the draft report. The NWTT Annual
Training Exercise Report and Testing Activity Report can be
consolidated with other exercise reports from other range complexes in
the Pacific Ocean for a single Pacific Exercise Report, if desired. The
annual report must contain information on the total hours of operation
of MF1 surface ship hull-mounted mid-frequency active sonar used during
training and testing activities in the Olympic Coast National Marine
Sanctuary Mitigation Area and a summary of all sound sources used,
including within specific mitigation reporting areas as described in
paragraph (e)(2) of this section. The analysis in the detailed report
must be based on the accumulation of data from the current year's
report and data collected from previous annual reports. The annual
report will also contain cumulative sonar and explosive use quantity
from previous years' reports through the current year. Additionally, if
there were any changes to the sound source allowance in a given year,
or cumulatively, the report must include a discussion of why the change
was made and include analysis to support how the change did or did not
affect the analysis in the NWTT SEIS/OEIS and MMPA final rule. The
annual report must also include details regarding specific requirements
associated with the mitigation areas listed in Sec. 218.144(b). The
analysis in the detailed report will be based on the accumulation of
data from the current year's report and data collected from previous
reports. The final annual/close-out report at the conclusion of the
authorization period (year seven) will serve as the comprehensive
close-out report and include both the final year annual incidental take
compared to annual authorized incidental take as well as a cumulative
seven-year incidental take compared to seven-year authorized incidental
take. The detailed reports must contain information identified in
paragraphs (e)(1) through (3) of this section.
(1) Summary of sources used. This section of the report must
include the following information summarized from the authorized sound
sources used in all training and testing events:
(i) Total annual hours or quantity (per the LOA) of each bin of
sonar and other transducers, and
(ii) Total annual expended/detonated ordinance (missiles, bombs,
sonobuoys, etc.) for each explosive bin.
(2) NWTT Study Area Mitigation Areas. The report must include any
Navy activities that occurred as specifically described in areas
identified in Sec. 218.144(b). Information included in the classified
annual reports may be used to inform future adaptive management of
activities within the NWTT Study Area.
(3) Geographic information presentation. The reports must present
an annual (and seasonal, where practical) depiction of training and

[[Page 34048]]

testing bin usage geographically across the NWTT Study Area.
(f) Seven-year close-out report. The final (year seven) draft
annual/close-out report must be submitted within three months after the
expiration of this subpart to the Director, Office of Protected
Resources, NMFS. NMFS will submit comments on the draft close-out
report, if any, within three months of receipt. The report will be
considered final after the Navy has addressed NMFS' comments, or three
months after submittal of the draft if NMFS does not provide comments
on the draft report.

Sec. 218.146 Letters of Authorization.

(a) To incidentally take marine mammals pursuant to this subpart,
the Navy must apply for and obtain an LOA in accordance with Sec.
216.106 of this chapter.
(b) An LOA, unless suspended or revoked, may be effective for a
period of time not to exceed the expiration date of this subpart.
(c) If an LOA expires prior to the expiration date of this subpart,
the Navy may apply for and obtain a renewal of the LOA.
(d) In the event of projected changes to the activity or to
mitigation, monitoring, or reporting (excluding changes made pursuant
to the adaptive management provision of Sec. 218.147(c)(1)) required
by an LOA issued under this subpart, the Navy must apply for and obtain
a modification of the LOA as described in Sec. 218.147.
(e) Each LOA will set forth:
(1) Permissible methods of incidental taking;
(2) Geographic areas for incidental taking;
(3) Means of effecting the least practicable adverse impact (i.e.,
mitigation) on the species and stocks of marine mammals and their
habitat; and
(4) Requirements for monitoring and reporting.
(f) Issuance of the LOA(s) will be based on a determination that
the level of taking is consistent with the findings made for the total
taking allowable under this subpart.
(g) Notice of issuance or denial of the LOA(s) will be published in
the Federal Register within 30 days of a determination.

Sec. 218.147 Renewals and modifications of Letters of Authorization.

(a) An LOA issued under Sec. Sec. 216.106 of this chapter and
218.146 for the activity identified in Sec. 218.140(c) may be renewed
or modified upon request by the applicant, provided that:
(1) The planned specified activity and mitigation, monitoring, and
reporting measures, as well as the anticipated impacts, are the same as
those described and analyzed for this subpart (excluding changes made
pursuant to the adaptive management provision in paragraph (c)(1) of
this section); and
(2) NMFS determines that the mitigation, monitoring, and reporting
measures required by the previous LOA(s) were implemented.
(b) For LOA modification or renewal requests by the applicant that
include changes to the activity or to the mitigation, monitoring, or
reporting measures (excluding changes made pursuant to the adaptive
management provision in paragraph (c)(1) of this section) that do not
change the findings made for this subpart or result in no more than a
minor change in the total estimated number of takes (or distribution by
species or stock or years), NMFS may publish a notice of planned LOA in
the Federal Register, including the associated analysis of the change,
and solicit public comment before issuing the LOA.
(c) An LOA issued under Sec. Sec. 216.106 of this chapter and
218.146 may be modified by NMFS under the following circumstances:
(1) Through Adaptive Management, after consulting with the Navy
regarding the practicability of the modifications, NMFS may modify
(including adding or removing measures) the existing mitigation,
monitoring, or reporting measures if doing so creates a reasonable
likelihood of more effectively accomplishing the goals of the
mitigation and monitoring.
(i) Possible sources of data that could contribute to the decision
to modify the mitigation, monitoring, or reporting measures in an LOA
include:
(A) Results from the Navy's monitoring from the previous year(s);
(B) Results from other marine mammal and/or sound research or
studies; or
(C) Any information that reveals marine mammals may have been taken
in a manner, extent, or number not authorized by this subpart or
subsequent LOAs.
(ii) If, through adaptive management, the modifications to the
mitigation, monitoring, or reporting measures are substantial, NMFS
will publish a notice of planned LOA in the Federal Register and
solicit public comment.
(2) If NMFS determines that an emergency exists that poses a
significant risk to the well-being of the species or stocks of marine
mammals specified in LOAs issued pursuant to Sec. Sec. 216.106 of this
chapter and 218.146, an LOA may be modified without prior notice or
opportunity for public comment. Notice would be published in the
Federal Register within thirty days of the action.

Sec. 218.148 [Reserved]

[FR Doc. 2020-08533 Filed 5-22-20; 11:15 am]
BILLING CODE 3510-22-P

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