Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy Training and Testing Activities in the Mariana Islands Training and Testing Study Area, 46111-46171 [2015-18633]

Download as PDF Vol. 80 Monday, No. 148 August 3, 2015 Part II Department of Commerce mstockstill on DSK4VPTVN1PROD with RULES2 National Oceanic and Atmospheric Administration 50 CFR Part 218 Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy Training and Testing Activities in the Mariana Islands Training and Testing Study Area; Final Rule VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 PO 00000 Frm 00001 Fmt 4717 Sfmt 4717 E:\FR\FM\03AUR2.SGM 03AUR2 46112 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations Overseas Environmental Impact Statement (FEIS/OEIS) for MITT, which also contains a list of the references used in this document, may be viewed at https://www.mitt-eis.com. Documents cited in this rule may also be viewed, by appointment, during regular business hours, at the aforementioned address (see ADDRESSES). DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 218 [Docket No. 140211133–5621–01] RIN 0648–BD69 Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy Training and Testing Activities in the Mariana Islands Training and Testing Study Area National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Final rule. AGENCY: Upon application from the U.S. Navy (Navy), we (the National Marine Fisheries Service) are issuing regulations under the Marine Mammal Protection Act (MMPA) to govern the unintentional taking of marine mammals incidental to training and testing activities conducted in the Mariana Islands Training and Testing (MITT) Study Area from August 2015 through August 2020. These regulations allow us to issue a Letter of Authorization (LOA) for the incidental take of marine mammals during the Navy’s specified activities and timeframes, set forth the permissible methods of taking, set forth other means of effecting the least practicable adverse impact on marine mammal species or stocks and their habitat, and set forth requirements pertaining to the monitoring and reporting of the incidental take. DATES: Effective August 3, 2015 through August 3, 2020. ADDRESSES: To obtain an electronic copy of the Navy’s application or other referenced documents, visit the Internet at: https://www.nmfs.noaa.gov/pr/ permits/incidental/. Documents cited in this rule may also be viewed, by appointment, during regular business hours, at 1315 East-West Highway, SSMC III, Silver Spring, MD 20912. FOR FURTHER INFORMATION CONTACT: John Fiorentino, Office of Protected Resources, NMFS, (301) 427–8401. SUPPLEMENTARY INFORMATION: mstockstill on DSK4VPTVN1PROD with RULES2 SUMMARY: Availability A copy of the Navy’s application, which contains a list of the references used in this document, may be obtained by visiting the internet at: https:// www.nmfs.noaa.gov/pr/permits/ incidental. The Navy’s Final Environmental Impact Statement/ VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Background Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) direct the Secretary of Commerce 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, a notice of a proposed authorization is provided to the public for review. Authorization for incidental takings shall be granted if NMFS finds that the taking will have a negligible impact on the species or stock(s), will not have an unmitigable adverse impact on the availability of the species or stock(s) for subsistence uses (where relevant), and if the permissible methods of taking and requirements pertaining to the mitigation, monitoring, and reporting of such takings are set forth. NMFS has defined ‘‘negligible impact’’ in 50 CFR 216.103 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.’’ The National Defense Authorization Act of 2004 (NDAA) (Pub. L. 108–136) removed the ‘‘small numbers’’ and ‘‘specified geographical region’’ limitations indicated above and amended the definition of ‘‘harassment’’ as it applies to a ‘‘military readiness activity’’ to read as follows (section 3(18)(B) of the MMPA): ‘‘(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].’’ Summary of Request On April 22, 2013, NMFS received an application from the Navy requesting an PO 00000 Frm 00002 Fmt 4701 Sfmt 4700 LOA for the take of 26 species of marine mammals incidental to Navy training and testing activities to be conducted in the MITT Study Area over 5 years. The Navy is requesting regulations that would establish a process for authorizing take, via one 5-year LOA, of marine mammals for training and testing activities, proposed to be conducted from 2015 through 2020. The Study Area includes the existing Mariana Islands Range Complex (MIRC) and surrounding seas, a transit corridor between the Mariana Islands and the Navy’s Hawaii Range Complex, and Navy pierside locations where sonar maintenance or testing may occur (see Figure 2–1 of the Navy’s LOA application for a map of the MITT Study Area). These activities are classified as military readiness activities. Marine mammals present in the Study Area may be exposed to sound from active sonar and underwater detonations. The Navy is requesting authorization to take 26 marine mammal species by Level B harassment (behavioral) and two species by Level A harassment (injury). The Navy’s application and the MITT FEIS/OEIS contain acoustic thresholds that, in some instances, represent changes from what NMFS has used to evaluate the Navy’s activities for previous authorizations. The revised thresholds, which the Navy developed in coordination with NMFS, are based on the evaluation and inclusion of new information from recent scientific studies; a detailed explanation of how they were derived is provided in the MITT FEIS/OEIS Criteria and Thresholds Technical Report (available at https://www.mitt-eis.com). The revised thresholds are adopted for this rulemaking after providing the public with an opportunity for review and comment via the proposed rule for this action, which published on March 19, 2014 (79 FR 15388). Further, more generally, NMFS is committed to the use of the best available science. NMFS uses an adaptive transparent process that allows for both timely scientific updates and public input into agency decisions regarding the use of acoustic research and thresholds. NOAA is currently in the process of developing Acoustic Guidance (the Guidance) on thresholds for onset of auditory impacts from exposure to sound, which will be used to support assessments of the effects of anthropogenic sound on marine mammals. To develop this Guidance, NOAA is compiling, interpreting, and synthesizing the best information currently available on the effects of anthropogenic sound on marine mammals, and is committed to E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations finalizing the Guidance through a systematic, transparent process that involves internal review, external peer review, and public comment. In December 2013, NOAA released for public comment draft Acoustic Guidance that provides acoustic threshold levels for onset of permanent threshold shift (PTS) and temporary threshold shifts (TTS) in marine mammals for all sound sources. NOAA has since been working to incorporate the relevant information received during the public comment period and to make appropriate changes. In January 2015, while NOAA was still working to finalize the Guidance, the U.S. Navy provided NOAA with a technical paper by Finneran (2015) describing Navy’s proposed methodology for updating auditory weighting functions and numeric thresholds for predicting onset of auditory effects (TTS/PTS thresholds) on marine animals exposed to active sonars and other active acoustic sources utilized during Navy training and testing activities. NOAA is working to evaluate and incorporate the information in Finneran (2015) into its Acoustic Guidance before it becomes final. Before doing so, NOAA will complete an independent peer review of the Navy’s technical paper and provide an additional public comment period for the draft Guidance. After the second peer review and public comment processes are complete, NOAA will determine how best to incorporate the Navy’s methodology into its final Acoustic Guidance. The Guidance likely will not be finalized until later this year. Thereafter, any new Navy modeling based on our final Acoustic Guidance would likely take a minimum of several months to complete. Consequently, the results of prior Navy modeling described in this rule represent the best available estimate of the number and type of take that may result from the Navy’s use of acoustic sources in the MITT Study Area. NOAA’s continued evaluation of all available science for the Acoustic Guidance could result in changes to the acoustic criteria used to model the Navy’s activities in the MITT Study Area, and, consequently, the enumerations of ‘‘take’’ estimates. However, consideration of the draft Guidance and information contained in Finneran (2015) does not alter our assessment of the likely responses of affected marine mammal species to acoustic sources employed by Navy in the MITT Study Area, or the likely fitness consequences of those responses. Further, while acoustic criteria may also inform mitigation and monitoring decisions, the Navy has a robust VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 adaptive management program that regularly addresses new information and allows for modification of mitigation and/or monitoring measures as appropriate. Description of the Specified Activity The proposed rule (79 FR 15388, March 19, 2014) and MITT FEIS/OEIS include a complete description of the Navy’s specified activities that are being authorized in this final rule. Sonar use and underwater detonations are the stressors most likely to result in impacts on marine mammals that could rise to the level of harassment. Detailed descriptions of these activities are provided in the MITT FEIS/OEIS and LOA application (https:// www.nmfs.noaa.gov/pr/permits/ incidental/) and are summarized here. Overview of Training Activities The Navy, U.S. Air Force, U.S. Marine Corps, and U.S. Coast Guard routinely train in the MITT Study Area in preparation for national defense missions. Training activities are categorized into eight functional warfare areas (anti-air warfare; amphibious warfare; strike warfare; anti-surface warfare; anti-submarine warfare; electronic warfare; mine warfare; and naval special warfare). The Navy determined that the following stressors used in these warfare areas are most likely to result in impacts on marine mammals: • Anti-surface warfare (underwater detonations) • Anti-submarine warfare (active sonar, underwater detonations) • Mine warfare (active sonar, underwater detonations) • Naval special warfare (underwater detonations) Additionally, some activities described as Major Training Activities in the MITT FEIS/OEIS and other activities are included in the analysis. The Navy’s activities in amphibious warfare, anti-air warfare, strike warfare, and electronic warfare do not involve stressors that could result in harassment of marine mammals. Therefore, these activities are not discussed further. The analysis and rationale for excluding these warfare areas are contained in the MITT FEIS/OEIS. Overview of Testing Activities The Navy researches, develops, tests, and evaluates new platforms, systems, and technologies. Many tests are conducted in realistic conditions at sea, and can range in scale from testing new software to operating portable devices to conducting tests of live weapons to PO 00000 Frm 00003 Fmt 4701 Sfmt 4700 46113 ensure they function as intended. Testing activities may occur independently of or in conjunction with training activities. Many testing activities are conducted similarly to Navy training activities and are also categorized under one of the primary mission areas. Other testing activities are unique and are described within their specific testing categories. The Navy determined that stressors used during the following testing activities are most likely to result in impacts on marine mammals: • Naval Air Systems Command (NAVAIR) Testing Æ Anti-surface warfare testing (underwater detonations) Æ Anti-submarine warfare testing (active sonar, underwater detonations) • Naval Sea Systems command (NAVSEA) Testing Æ New ship construction (active sonar, underwater detonations) Æ Life cycle activities (active sonar, underwater detonations) Æ Anti-surface warfare/anti-submarine warfare testing (active sonar, underwater detonations) Æ Ship protection systems and swimmer defense testing (active sonar) • Office of Naval Research (ONR) and Naval Research Laboratory (NRL) Testing Æ ONR/NRL research, development, test, and evaluation (active sonar) Other Navy testing activities do not involve stressors that could result in marine mammal harassment. Therefore, these activities are not discussed further. Classification of Non-Impulsive and Impulsive Sources Analyzed In order to better organize and facilitate the analysis of about 300 sources of underwater non-impulsive sound or impulsive energy, the Navy developed a series of source classifications, or source bins. This method of analysis provides the following benefits: • Allows for new sources to be covered under existing authorizations, as long as those sources fall within the parameters of a ‘‘bin;’’ • Simplifies the data collection and reporting requirements anticipated under the MMPA; • Ensures a conservative approach to all impact analysis because all sources in a single bin are modeled as the loudest source (e.g., lowest frequency, highest source level, longest duty cycle, or largest net explosive weight within that bin); E:\FR\FM\03AUR2.SGM 03AUR2 46114 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations • Allows analysis to be conducted more efficiently, without compromising the results; • Provides a framework to support the reallocation of source usage (hours/ explosives) between different source bins, as long as the total number and severity of marine mammal 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. A description of each source classification is provided in Tables 1 and 2. Non-impulsive sources are grouped into bins based on the frequency, source level when warranted, and how the source would be used. Impulsive bins are based on the net explosive weight of the munitions or explosive devices. The following factors further describe how non-impulsive sources are divided: • Frequency of the non-impulsive source: Æ Low-frequency sources operate below 1 kilohertz (kHz) Æ Mid-frequency sources operate at or above 1 kHz, up to and including 10 kHz Æ High-frequency sources operate above 10 kHz, up to and including 100 kHz Æ Very high-frequency sources operate above 100, but below 200 kHz • Source level of the non-impulsive source: Æ Greater than 160 decibels (dB), but less than 180 dB Æ Equal to 180 dB and up to 200 dB Æ Greater than 200 dB How a sensor is used determines how the sensor’s acoustic emissions are analyzed. Factors to consider include pulse length (time source is on); beam pattern (whether sound is emitted as a narrow, focused beam, or, as with most explosives, in all directions); and duty cycle (how often a transmission occurs in a given time period during an event). There are also non-impulsive sources with characteristics that are not anticipated to result in takes of marine mammals. These sources have low source levels, narrow beam widths, downward directed transmission, short pulse lengths, frequencies beyond known hearing ranges of marine mammals, or some combination of these factors. These sources generally have frequencies greater than 200 kHz and/or source levels less than 160 dB and are qualitatively analyzed in the MITT FEIS/OEIS. TABLE 1—IMPULSIVE TRAINING AND TESTING SOURCE CLASSES ANALYZED Net explosive weight (lbs) Source class Representative munitions E1 .................................................... E2 .................................................... E3 .................................................... E4 .................................................... E5 .................................................... E6 .................................................... E8 .................................................... E9 .................................................... E10 .................................................. E11 .................................................. E12 .................................................. Medium-caliber projectiles ....................................................................... Medium-caliber projectiles ....................................................................... Large-caliber projectiles .......................................................................... Improved Extended Echo Ranging Sonobuoy ........................................ 5 in. (12.7 cm) projectiles ........................................................................ 15 lb. (6.8 kg) shaped charge ................................................................. 250 lb. (113.4 kg) bomb .......................................................................... 500 lb. (226.8 kg) bomb .......................................................................... 1,000 lb. (453.6 kg) bomb ....................................................................... 650 lb. (294.8 kg) mine ........................................................................... 2,000 lb. (907.2 kg) bomb ....................................................................... 0.1–0.25 (45.4–113.4 g) 0.26–0.5 (117.9–226.8 g) >0.5–2.5 (>226.8 g–1.1 kg) >2.5–5.0 (1.1–2.3 kg) >5–10 (>2.3–4.5 kg) >10–20 (>4.5–9.1 kg) >60–100 (>27.2–45.4 kg) >100–250 (>45.4–113.4 kg) >250–500 (>113.4–226.8 kg) >500–650 (>226.8–294.8 kg) >650–1,000 (>294.8–453.6 kg) TABLE 2—NON-IMPULSIVE TRAINING AND TESTING SOURCE CLASSES ANALYZED Source class Source class category Low-Frequency (LF): Sources that produce low-frequency (less than 1 kilohertz [kHz]) signals. LF4 LF5 LF6 Mid-Frequency (MF): Tactical and non-tactical sources that produce mid-frequency (1 to 10 kHz) signals. MF1 Low-frequency sources equal to 180 dB and up to 200 dB. Low-frequency sources less than 180 dB. Low-frequency sonar currently in development (e.g., anti-submarine warfare sonar associated with the Littoral Combat Ship). Active hull-mounted surface ship sonar (e.g., AN/SQS–53C and AN/SQS–60). Active hull-mounted surface ship sonar (e.g., AN/SQS–56). Active hull-mounted submarine sonar (e.g., AN/BQQ–10). Active helicopter-deployed dipping sonar (e.g., AN/AQS–22 and AN/AQS–13). Active acoustic sonobuoys (e.g., DICASS). Active underwater sound signal devices (e.g., MK–84). Active sources (greater than 200 dB) not otherwise binned. Active sources (equal to 180 dB and up to 200 dB). Active sources (greater than 160 dB, but less than 180 dB) not otherwise binned. Hull-mounted surface ship sonar with an active duty cycle greater than 80%. High duty cycle—variable depth sonar. Active hull-mounted submarine sonar (e.g., AN/BQQ–10). Active mine detection, classification, and neutralization sonar (e.g., AN/SQS–20). Active sources (greater than 200 dB). Active sources (equal to 180 dB and up to 200 dB). MF active Deep Water Active Distributed System (DWADS). MF active Multistatic Active Coherent (MAC) sonobuoy (e.g., AN/SSQ–125). MF2 MF3 MF4 MF5 MF6 MF8 MF9 MF10 mstockstill on DSK4VPTVN1PROD with RULES2 MF11 High-Frequency (HF) and Very High-Frequency (VHF): Tactical and non-tactical sources that produce high-frequency (greater than 10 kHz but less than 200 kHz) signals. Anti-Submarine Warfare (ASW): Tactical sources such as active sonobuoys and acoustic countermeasures systems used during ASW training and testing activities. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 PO 00000 Frm 00004 MF12 HF1 HF4 HF5 HF6 ASW1 ASW2 Fmt 4701 Description Sfmt 4700 E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 46115 TABLE 2—NON-IMPULSIVE TRAINING AND TESTING SOURCE CLASSES ANALYZED—Continued Source class Source class category Description ASW3 Torpedoes (TORP): Source classes associated with active acoustic signals produced by torpedoes. Acoustic Modems (M): Systems used to transmit data acoustically through water. Swimmer Detection Sonar (SD): Systems used to detect divers and submerged swimmers. Airguns (AG) 1: Underwater airguns are used during swimmer defense and diver deterrent training and testing activities. 1 There MF active towed active acoustic countermeasure systems (e.g., AN/SLQ–25). Lightweight torpedo (e.g., MK–46, MK–54, or Anti-Torpedo Torpedo). Heavyweight torpedo (e.g., MK–48). Mid-frequency acoustic modems (greater than 190 dB). TORP1 TORP2 M3 SD1 High-frequency sources with short pulse lengths, used for the detection of swimmers and other objects for the purpose of port security. Up to 60 cubic inch airguns (e.g., Sercel Mini-G). AG are no Level A or Level B takes proposed from airguns; therefore, airguns are not discussed further in this rule. Proposed Action The Navy proposes to continue conducting training and testing activities within the MITT Study Area. The Navy has been conducting military readiness training and testing activities in the MITT Study Area for decades. Training and Testing The Navy proposes to conduct training and testing activities in the Study Area as described in Tables 3 and 4. Detailed information about each proposed activity (stressor, training or testing event, description, sound source, duration, and geographic location) can be found in the MITT FEIS/OEIS. NMFS used the detailed information in the MITT FEIS/OEIS to help analyze the potential impacts to marine mammals. Table 3 describes the annual number of impulsive source detonations during training and testing activities within the Study Area, and Table 4 describes the annual number of hours or items of nonimpulsive sources used during training and testing within the Study Area. TABLE 3—ANNUAL NUMBER OF IMPULSIVE SOURCE DETONATIONS DURING TRAINING AND TESTING ACTIVITIES IN THE STUDY AREA Explosive class Net explosive weight (NEW) E1 ..... Annual in-water detonations (0.1 lb.–0.25 lb.) ..... 10,140 TABLE 3—ANNUAL NUMBER OF IMPULSIVE SOURCE DETONATIONS DURING TRAINING AND TESTING ACTIVITIES IN THE STUDY AREA—Continued Explosive class Net explosive weight (NEW) E2 ..... E3 ..... E4 ..... E5 ..... E6 ..... E8 ..... E9 ..... E10 ... E11 ... E12 ... (0.26 lb.–0.5 lb.) ..... (>0.5 lb.–2.5 lb.) .... (>2.5 lb.–5 lb.) ....... (>5 lb.–10 lb.) ........ (>10 lb.–20 lb.) ...... (>60 lb.–100 lb.) .... (>100 lb.–250 lb.) .. (>250 lb.–500 lb.) .. (>500 lb.–650 lb.) .. (>650 lb.–2,000 lb.) Annual in-water detonations 106 932 420 684 76 16 4 12 6 184 TABLE 4—ANNUAL HOURS OR ITEMS OF NON-IMPULSIVE SOURCES USED DURING TRAINING AND TESTING ACTIVITIES WITHIN THE STUDY AREA Source class category Source class Low-Frequency (LF): Sources that produce signals less than 1 kHz ........................ Mid-Frequency (MF): Tactical and non-tactical sources from 1 to 10 kHz ................ mstockstill on DSK4VPTVN1PROD with RULES2 High-Frequency (HF) and Very High-Frequency (VHF): Tactical and non-tactical sources that produce signals greater than 10 kHz but less than 200 kHz. Anti-Submarine Warfare (ASW): Tactical sources used during anti-submarine warfare training and testing activities. Torpedoes (TORP): Source classes associated with active acoustic signals produced by torpedoes. Acoustic Modems (M): Transmit data acoustically through the water ....................... Swimmer Detection Sonar (SD): Used to detect divers and submerged swimmers VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 PO 00000 Frm 00005 Fmt 4701 Sfmt 4700 LF4 LF5 LF6 MF1 MF2 MF3 MF4 MF5 MF6 MF8 MF9 MF10 MF11 MF12 HF1 HF4 HF5 HF6 ASW1 ASW2 ASW3 ASW4 TORP1 TORP2 M3 SD1 E:\FR\FM\03AUR2.SGM Annual use 123 hours. 11 hours. 40 hours. 1,872 hours. 625 hours. 192 hours. 214 hours. 2,588 items. 33 items. 123 hours. 47 hours. 231 hours. 324 hours. 656 hours. 113 hours. 1,060 hours. 336 hours. 1,173 hours. 144 hours. 660 items. 3,935 hours. 32 items. 115 items. 62 items. 112 hours. 2,341 hours. 03AUR2 46116 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations Vessels Vessels used as part of the proposed action include ships, submarines, and boats ranging in size from small, 5-m Rigid Hull Inflatable Boats to 333-m long aircraft carriers. Representative Navy vessel types, lengths, and speeds used in both training and testing activities are shown in Table 5. While these speeds are representative, some vessels operate outside of these speeds due to unique training or safety requirements for a given event. Examples include increased speeds needed for flight operations, full speed runs to test engineering equipment, time critical positioning needs, etc. Examples of decreased speeds include speeds less than 5 knots or completely stopped for launching small boats, certain tactical maneuvers, target launch or retrievals, etc. The number of Navy vessels in the Study Area varies based on training and testing schedules. Most activities include either one or two vessels, with an average of one vessel per activity, and last from a few hours up to two weeks. Multiple ships, however, can be involved with major training events, although ships can often operate for extended periods beyond the horizon and out of visual sight from each other. TABLE 5—TYPICAL NAVY BOAT AND VESSEL TYPES WITH LENGTH GREATER THAN 18 METERS USED WITHIN THE MITT STUDY AREA Vessel type (>18 m) Example(s) (specifications in meters (m) for length, metric tons (mt) for mass, and knots for speed) Aircraft Carrier ............................................ Aircraft Carrier (CVN) length: 333 m beam: 41 m draft: 12 m displacement: 81,284 mt max. speed: 30+ knots. Cruiser (CG) length: 173 m beam: 17 m draft: 10 m displacement: 9,754 mt max. speed: 30+ knots. Destroyer (DDG) length: 155 m beam: 18 m draft: 9 m displacement: 9,648 mt max. speed: 30+ knots. Frigate (FFG) length: 136 m beam: 14 m draft: 7 m displacement: 4,166 mt max. speed: 30+ knots. Littoral Combat Ship (LCS) length: 115 m beam: 18 m draft: 4 m displacement: 3,000 mt max. speed: 40+ knots. Amphibious Assault Ship (LHA, LHD) length: 253 m beam: 32 m draft: 8 m displacement: 42,442 mt max. speed: 20+ knots. Amphibious Transport Dock (LPD) length: 208 m beam: 32 m draft: 7 m displacement: 25,997 mt max. speed: 20+ knots. Dock Landing Ship (LSD) length: 186 m beam: 26 m draft: 6 m displacement: 16,976 mt max. speed: 20+ knots. Mine Countermeasures Ship (MCM) length: 68 m beam: 12 m draft: 4 m displacement: 1,333 max. speed: 14 knots. Attack Submarine (SSN) length: 115 m beam: 12 m draft: 9 m displacement: 12,353 mt max. speed: 20+ knots. Guided Missile Submarine (SSGN) length: 171 m beam: 13 m draft: 12 m displacement: 19,000 mt max. speed: 20+ knots. Fast Combat Support Ship (T–AOE) length: 230 m beam: 33 m draft: 12 m displacement: 49,583 max. speed: 25 knots. Dry Cargo/Ammunition Ship (T–AKE) length: 210 m beam: 32 m draft: 9 m displacement: 41,658 mt max speed: 20 knots. Fleet Replenishment Oilers (T–AO) length: 206 m beam: 30 m draft: 11 displacement: 42,674 mt max. speed: 20 knots. Fleet Ocean Tugs (T–ATF) length: 69 m beam: 13 m draft: 5 m displacement: 2,297 max. speed: 14 knots. Joint High Speed Vessel (JHSV) 2 length: 103 m beam; 28.5 m draft; 4.57 m displacement; 2,362 mt max speed: 40 knots. Landing Craft, Utility (LCU) length: 41 m beam: 9 m draft: 2 m displacement: 381 mt max. speed: 11 knots. Landing Craft, Mechanized (LCM) length: 23 m beam: 6 m draft: 1 m displacement: 107 mt max. speed: 11 knots. MK V Special Operations Craft length: 25 m beam: 5 m displacement: 52 mt max. speed: 50 knots. Surface Combatants ................................... Amphibious Warfare Ships ......................... Mine Warship Ship ..................................... Submarines ................................................ Combat Logistics Force Ships 1 ................. Support Craft/Other .................................... Support Craft/Other Speed. Specialized High Typical operating speed (knots) 10 to 15. 10 to 15. 10 to 15. 5 to 8. 8 to 13. 8 to 12. 3 to 5. Variable. 1 CLF vessels are not permanently homeported in the Marianas, but are used for various fleet support and training support events in the Study Area. 2 Typical operating speed of the Joint High Speed Vessel is 25–32 knots. mstockstill on DSK4VPTVN1PROD with RULES2 Dates and Location The description of the location of authorized activities has not changed from what was provided in the proposed rule (79 FR 15388, March 19, 2014; pages 15394–15395) and MITT FEIS/OEIS (https://www.mitt-eis.com). For a complete description, please see those documents. Training and testing activities will be conducted in the MITT VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Study Area for the reasonably foreseeable future. The MITT Study Area is comprised of the established ranges, operating areas, and special use airspace in the region of the Mariana Islands that are part of the Mariana Islands Range Complex (MIRC), its surrounding seas, and a transit corridor between the Mariana Islands and the Hawaii Range Complex. The defined PO 00000 Frm 00006 Fmt 4701 Sfmt 4700 Study Area has expanded beyond the areas included in previous Navy authorizations to include transit routes and pierside locations. This expansion is not an increase in the Navy’s training and testing area, but rather an increase in the area to be analyzed (i.e., not previously analyzed) under an incidental take authorization in support of the MITT EIS/OEIS. The MIRC, like E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations all Navy range complexes, is an organized and designated set of specifically bounded geographic areas, which includes a water component (above and below the surface), airspace, and sometimes a land component. Operating areas (OPAREAs) and special use airspace are established within each range complex. These designations are further described in Chapter 2 of the Navy’s LOA application. mstockstill on DSK4VPTVN1PROD with RULES2 Description of Marine Mammals in the Area of the Specified Activity Twenty-six marine mammal species may occur in the Study Area, including seven mysticetes (baleen whales) and 19 odontocetes (dolphins and toothed whales). The Description of Marine Mammals in the Area of the Specified Activities section has not changed from what was in the proposed rule (79 FR 15388, March 19, 2014; pages 15395– 15396). Table 6 of the proposed rule provided a list of marine mammals with possible or confirmed occurrence within the MITT Study Area, including stock, abundance, and status. Since publishing the proposed rule, NMFS released new stock assessment reports for some of the marine mammal species occurring within the MITT Study Area. The new species abundance estimates were considered in making our final determinations. The MITT FEIS/OEIS includes the revised species abundance estimates. Although not repeated in this final rule, we have reviewed these data, determined them to be the best available scientific information for the purposes of the rulemaking, and consider this information part of the administrative record for this action. The proposed rule, the Navy’s LOA application, and the MITT FEIS/OEIS include a complete description of information on the status, distribution, abundance, vocalizations, density estimates, and general biology of marine mammal species in the Study Area. In addition, NMFS publishes annual stock assessment reports for marine mammals, including some stocks that occur within the Study Area (https:// www.nmfs.noaa.gov/pr/species/ mammals). Potential Effects of Specified Activities on Marine Mammals The Navy has requested authorization for the take of marine mammals that may occur incidental to training and testing activities in the Study Area. The Navy has analyzed potential impacts to marine mammals from impulsive and non-impulsive sound sources and vessel strike. Other potential impacts to marine mammals from training activities in the VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Study Area were analyzed in the MITT FEIS/OEIS, in consultation with NMFS as a cooperating agency, and determined to be unlikely to result in marine mammal harassment. Therefore, the Navy has not requested authorization for take of marine mammals that might occur incidental to other components of their proposed activities. In this document, NMFS analyzes the potential effects on marine mammals from exposure to non-impulsive sound sources (sonar and other active acoustic sources), impulsive sound sources (underwater detonations), and vessel strikes. For the purpose of MMPA authorizations, NMFS’ effects assessments serve four primary purposes: (1) To prescribe the permissible methods of taking (i.e., Level B harassment (behavioral harassment), Level A harassment (injury), or mortality, including an identification of the number and types of take that could occur by harassment or mortality) and to prescribe other means of effecting the least practicable adverse impact on such species or stock and its habitat (i.e., mitigation); (2) to determine whether the specified activity would have a negligible impact on the affected species or stocks of marine mammals (based on the likelihood that the activity would adversely affect the species or stock through effects on annual rates of recruitment or survival); (3) to determine whether the specified activity would have an unmitigable adverse impact on the availability of the species or stock(s) for subsistence uses; and (4) to prescribe requirements pertaining to monitoring and reporting. This section focuses qualitatively on the different ways that non-impulsive and impulsive sources may affect marine mammals (some of which NMFS would not classify as harassment). In the Estimated Take section, we will relate the potential effects to marine mammals from non-impulsive and impulsive sources to the MMPA definitions of Level A and Level B harassment and will attempt to quantify those effects. Non-Impulsive Sources Direct Physiological Effects Based on the literature, there are two basic ways that non-impulsive sources might directly result in physical trauma or damage: Noise-induced loss of hearing sensitivity (more commonlycalled ‘‘threshold shift’’) and acoustically mediated bubble growth. Separately, an animal’s behavioral reaction to an acoustic exposure could lead to physiological effects that might PO 00000 Frm 00007 Fmt 4701 Sfmt 4700 46117 ultimately lead to injury or death, which is discussed later in the Stranding section. Threshold Shift (noise-induced loss of hearing)—When animals exhibit reduced hearing sensitivity (i.e., sounds must be louder for an animal to detect them) following exposure to an intense sound or sound for long duration, it is referred to as a noise-induced threshold shift (TS). An animal can experience TTS or PTS. TTS can last from minutes or hours to days (i.e., there is complete recovery), can occur in specific frequency ranges (i.e., an animal might only have a temporary loss of hearing sensitivity between the frequencies of 1 and 10 kHz), and can be of varying amounts (for example, an animal’s hearing sensitivity might be reduced initially by only 6 dB or reduced by 30 dB). PTS is permanent, but some recovery is possible. PTS can also occur in a specific frequency range and amount as mentioned above for TTS. The following physiological mechanisms are thought to play a role in inducing auditory TS: 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 TS and the frequency range in which it occurs. As amplitude and duration of sound exposure increase, so, generally, does the amount of TS, along with the recovery time. For intermittent sounds, less TS could occur than compared to a continuous exposure with the same energy (some recovery could occur between intermittent exposures depending on the duty cycle between sounds) (Kryter et al., 1966; Ward, 1997). For example, one short but loud (higher SPL) sound exposure may induce the same impairment as one longer but softer 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, prolonged exposure to sounds 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). Although in the case of mid- and high-frequency active sonar (MFAS/HFAS), animals are not expected to be exposed to levels high E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46118 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations enough or durations long enough to result in PTS. 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). Although the published body of scientific literature contains numerous theoretical studies and discussion papers on hearing impairments that can occur with exposure to a loud sound, only a few studies provide empirical information on the levels at which noise-induced loss in hearing sensitivity occurs in nonhuman animals. For marine mammals, published data are limited to the captive bottlenose dolphin, beluga, harbor porpoise, and Yangtze finless porpoise (Finneran et al., 2000, 2002b, 2003, 2005a, 2007, 2010a, 2010b; Finneran and Schlundt, 2010; Lucke et al., 2009; Mooney et al., 2009a, 2009b; Popov et al., 2011a, 2011b; Kastelein et al., 2012a; Schlundt et al., 2000; Nachtigall et al., 2003, 2004). For pinnipeds in water, data are limited to measurements of TTS in harbor seals, an elephant seal, and California sea lions (Kastak et al., 1999, 2005; Kastelein et al., 2012b). Marine mammal hearing plays a critical role in communication with conspecifics, and 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 occurs during 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 time when communication is critical for successful mother/calf interactions could have more serious impacts. Also, depending on the degree and frequency range, the effects of PTS on an animal could range in severity, although it is considered generally more serious because it is a permanent condition. Of note, reduced hearing sensitivity as a simple function of aging has been observed in marine mammals, VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 as well as humans and other taxa (Southall et al., 2007), so one can infer that strategies exist for coping with this condition to some degree, though likely not without cost. Acoustically Mediated Bubble Growth—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 of sonar pings or explosion sounds 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 PO 00000 Frm 00008 Fmt 4701 Sfmt 4700 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. 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; Fernandez 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). 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). More recent 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). Although it has been argued that traumas from some recent beaked whale strandings are consistent with gas emboli and bubble-induced tissue separations (Jepson et al., 2003), there is no conclusive evidence of this. However, Jepson et al. (2003, 2005) and Fernandez et al. (2004, 2005, 2012) concluded that in vivo bubble formation, which may be exacerbated by E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES2 deep, long-duration, repetitive dives may explain why beaked whales appear to be particularly vulnerable to sonar exposures. Further investigation is needed to further assess the potential validity of these hypotheses. More information regarding hypotheses that attempt to explain how behavioral responses to non-impulsive sources can lead to strandings is included in the Stranding and Mortality section. Acoustic Masking Marine mammals use acoustic signals for a variety of purposes, which differ among species, but include communication between individuals, navigation, foraging, reproduction, and learning about their environment (Erbe and Farmer, 2000; Tyack, 2000). Masking, or auditory interference, generally occurs when sounds in the environment are louder than and of a similar frequency to, auditory signals an animal is trying to receive. Masking is a phenomenon that affects animals that are trying to receive acoustic information about their environment, including sounds from other members of their species, predators, prey, and sounds that allow them to orient in their environment. Masking these acoustic signals can disturb the behavior of individual animals, groups of animals, or entire populations. The extent of the masking interference depends on the spectral, temporal, and spatial relationships between the signals an animal is trying to receive and the masking noise, in addition to other factors. 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. 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 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 echolocation calls of toothed whales are subject to masking by high frequency sound. Human data indicate VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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 recent 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. As mentioned previously, the functional hearing ranges of mysticetes, odontocetes, and pinnipeds underwater all encompass the frequencies of the sonar sources used in the Navy’s MFAS/ HFAS training exercises. Additionally, almost all 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. For hullmounted sonar, which accounts for the largest takes of marine mammals (because of the source strength and number of hours it’s conducted), the pulse length and low duty cycle of the MFAS/HFAS signal makes it less likely that masking would occur as a result. Impaired Communication In addition to making it more difficult for animals to perceive 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’’ 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 animals 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 PO 00000 Frm 00009 Fmt 4701 Sfmt 4700 46119 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. 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 remain unknown, like most other trade-offs animals must make, some of these strategies probably come at a cost (Patricelli et al., 2006). For example, 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). Shifting songs and calls to higher frequencies may also impose energetic costs (Lambrechts, 1996). Stress Responses 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 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. 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 E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46120 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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; 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, 1995), altered metabolism (Elasser et al., 2000), reduced immune competence (Blecha, 2000), and behavioral disturbance. 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 a risk to the animal’s welfare. 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 function, which impairs those functions that experience the diversion. For example, when mounting a stress response diverts energy away from growth in young animals, those animals may experience stunted growth. When mounting 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 will last until the animal replenishes its biotic reserves sufficient to restore normal function. Note that these examples VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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 have also been documented fairly well through controlled experiments; because this physiology exists in every vertebrate that has been studied, it is not surprising that stress responses and their costs have been documented in both laboratory and freeliving 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). Information has also been collected on the physiological responses of marine mammals to exposure to anthropogenic sounds (Fair and Becker, 2000; Romano et al., 2002; Wright et al., 2008). 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. 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. The Office of Naval Research hosted a workshop (Effects of Stress on Marine Mammals Exposed to Sound) in 2009 that focused on this very topic (ONR, 2009). Studies of other marine animals and terrestrial animals would also lead us to expect some marine mammals to experience physiological stress responses and, perhaps, physiological responses that would be classified as ‘‘distress’’ upon exposure to high frequency, mid-frequency and lowfrequency sounds. For example, Jansen (1998) reported on the relationship between acoustic exposures and physiological responses that are indicative of stress responses in humans (for example, 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 physiology stress responses of endangered Sonoran pronghorn to military overflights. Smith et al. (2004a, 2004b), for example, identified noise-induced physiological transient stress responses in hearingspecialist fish (i.e., goldfish) that accompanied short- and long-term hearing losses. Welch and Welch (1970) PO 00000 Frm 00010 Fmt 4701 Sfmt 4700 reported physiological and behavioral stress responses that accompanied damage to the inner ears of fish and several mammals. Hearing is one of the primary senses marine mammals use to gather information about their environment and to communicate with conspecifics. Although empirical information on the relationship between sensory impairment (TTS, PTS, and acoustic masking) on marine mammals remains limited, it seems reasonable to assume that reducing an animal’s ability to gather information about its environment and to communicate with other members of its species would be stressful for animals that use hearing as their primary sensory mechanism. Therefore, we assume that acoustic exposures sufficient to trigger onset PTS or TTS would be accompanied by physiological stress responses because terrestrial animals exhibit those responses under similar conditions (NRC, 2003). More importantly, marine mammals might experience stress responses at received levels lower than those necessary to trigger onset TTS. Based on empirical studies of the time required to recover from stress responses (Moberg, 2000), we also assume that stress responses are likely to persist beyond the time interval required for animals to recover from TTS and might result in pathological and pre-pathological states that would be as significant as behavioral responses to TTS. Behavioral 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 effects whether it is less likely (habituation) or more likely (sensitization) to respond to certain sounds in the future (animals can also be innately pre-disposed 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), 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). 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, E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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. Exposure of marine mammals to sound sources can result in no response or responses including, but not limited to: 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 and others in 1995. A more recent review (Nowacek et al., 2007) addresses studies conducted since 1995 and focuses on observations where the received sound level of the exposed marine mammal(s) was known or could be estimated. The following sub-sections 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. Estimates of the types of 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. 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. 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). Flight responses have been speculated as being a component of marine mammal strandings associated with sonar activities (Evans and England, 2001). Response to Predator—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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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 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. Diving—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. 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 PO 00000 Frm 00011 Fmt 4701 Sfmt 4700 46121 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. Due to past incidents of beaked whale strandings associated with sonar operations, feedback paths are provided between avoidance and diving and indirect tissue effects. This feedback accounts for the hypothesis that variations in diving behavior and/or avoidance responses can possibly result in nitrogen tissue supersaturation and nitrogen off-gassing, possibly to the point of deleterious vascular bubble formation (Jepson et al., 2003). Although hypothetical, discussions surrounding this potential process are controversial. 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. 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) and sperm whales engaged in foraging dives did not abandon dives when exposed to distant signatures of seismic airguns (Madsen et al., 2006). However, Miller et al. (2009) reported buzz rates (a proxy for feeding) 19 percent lower during exposure to distant signatures of seismic airguns. 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 sound pressure levels 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 simulated mid-frequency sonar in the Southern California Bight were less likely to produce low frequency calls usually associated with ´ feeding behavior (Melcon et al., 2012). ´ However, Melcon et al. (2012) were unable to determine if suppression of low frequency calls reflected a change E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46122 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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 (Melcon 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 ´ (Melcon et al., 2012). Preliminary results from the 2010–2011 field season of an ongoing behavioral response study 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 mild and there was a quick return to their baseline activity (Southall et al., 2011). A determination of whether foraging disruptions incur fitness consequences will require 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. Goldbogen et al., (2013) monitored behavioral responses of tagged blue whales located in feeding areas when exposed simulated MFA sonar. Responses varied depending on behavioral context, with deep feeding whales being more significantly affected (i.e., generalized avoidance; cessation of feeding; increased swimming speeds; or directed travel away from the source) compared to surface feeding individuals that typically showed no change in behavior. Non-feeding whales also seemed to be affected by exposure. The authors 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. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Breathing—Variations in respiration naturally vary 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 (Southall et al., 2007; Henderson et al., 2014). 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., caused avoidance, masking, etc.) and no specific overview is provided here. However, social disruptions must be considered in context of the relationships that are affected. Longterm disruptions of mother/calf pairs or mating displays have the potential to affect the growth and survival or reproductive effort/success of individuals, respectively. Vocalizations (also see 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 may result in response to a need to compete with an increase in background noise or may reflect an increased vigilance or startle response. For example, in the presence of lowfrequency active sonar, humpback whales have been observed to increase the length of their ‘‘songs’’ (Miller et al., 2000; Fristrup et al., 2003), possibly due to the overlap in frequencies between the whale song and the low-frequency active sonar. A similar compensatory effect for the presence of low-frequency PO 00000 Frm 00012 Fmt 4701 Sfmt 4700 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). Killer whales off the northwestern coast of the U.S. 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. Avoidance—Avoidance is the displacement of an individual from an area as a result of the presence of a sound. Richardson et al., (1995) noted that avoidance reactions are the most obvious manifestations of disturbance in marine mammals. It 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. Longer term displacement is possible, however, which can lead to changes in abundance or distribution patterns of the species in the affected region if they do not become acclimated to the presence of the sound (Blackwell et al., 2004; Bejder et al., 2006; Teilmann et al., 2006). 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), while 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). 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- E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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 (which both contained mid- and low-frequency components) 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 1000 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 @1–2 kHz every 10 seconds for 10 minutes; Source B: With a 1.0 second upsweep 197 dB @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, ceased feeding during the approach of the sonar and moved rapidly away from the source. When exposed to Source B, Kvadsheim and his co-workers 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 orcas were consistent with the results of other studies. In 2007, the first in a series of behavioral response studies, a collaboration by the Navy, NMFS, and other scientists showed one beaked whale (Mesoplodon densirostris) 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 mid-frequency 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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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 re1mPa). This sensitivity is manifest 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. The response to such stimuli appears to involve maximizing the distance from the sound source. Stimpert et al. (2014) tagged a Baird’s beaked whale, which was subsequently exposed to simulated mid-frequency sonar. Received levels of sonar on the tag increased to a maximum of 138 dB re 1mPa, 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. Results from a 2007–2008 study conducted near the Bahamas showed a change in diving behavior of an adult Blainville’s beaked whale to playback of mid-frequency source and predator sounds (Boyd et al., 2008; Southall et al. 2009; Tyack et al., 2011). 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 have been 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 mid-frequency active sonar during the 2010 and 2011 field seasons of the southern California behavioral response study. The 2011 whale was also incidentally exposed to mid-frequency active sonar from a distant naval exercise. Received levels from the mid-frequency active sonar signals from the controlled and incidental exposures were calculated as 84–144 and 78–106 dB re 1 mPa root mean square (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 PO 00000 Frm 00013 Fmt 4701 Sfmt 4700 46123 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. 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. 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 2 hours after midfrequency source playback. Pilot whales and killer whales off Norway also exhibited horizontal avoidance of a transducer with outputs in the midfrequency 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 midfrequency sonar playback was observed on one occasion (Miller et al., 2011). 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). 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; Tyack et al., 2011). In the Bahamas, Blainville’s beaked whales located on the 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 E:\FR\FM\03AUR2.SGM 03AUR2 46124 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES2 2009; Moretti et al., 2009; McCarthy et al., 2011; Tyack et al., 2011). Moretti et al. (2014) used recordings from seafloormounted 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. 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. There are few empirical studies of avoidance responses of free-living cetaceans to MFAS. Much more information is available on the avoidance responses of free-living cetaceans to other acoustic sources, such as seismic airguns and lowfrequency tactical sonar, than MFAS. Behavioral Responses Southall et al. (2007) reports the results of the efforts of a panel of experts in acoustic research from behavioral, physiological, and physical disciplines that convened and 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, 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 were not included in the quantitative analysis for the criteria recommendations. 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. MFAS/HFAS sonar is considered a nonpulse sound. Southall et al. (2007) summarize the studies associated with low-frequency, mid-frequency, and high-frequency cetacean and pinniped VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 responses to non-pulse sounds, based strictly on received level, in Appendix C of their article (incorporated by reference and summarized in the three paragraphs below). 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 MFAS/HFAS) 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, Acoustic Thermometry of Ocean Climate (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 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 MFAS/HFAS) 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, while in other cases these responses were not seen in the 120 to 150 dB 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 MFAS/HFAS) 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 PO 00000 Frm 00014 Fmt 4701 Sfmt 4700 anthropogenic sounds at low received levels (∼ 90 to 120 dB), at least for initial exposures. All recorded exposures above 140 dB 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 is no data to indicate whether other high frequency cetaceans are as sensitive to anthropogenic sound as harbor porpoises are. The studies that address the responses of pinnipeds in water 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 MFAS/HFAS) including: AHDs, ATOC, various nonpulse sounds used in underwater data communication; underwater drilling, and construction noise. Few studies exist with enough information to include them in the analysis. The limited data suggested that exposures to non-pulse sounds between 90 and 140 dB generally do not result in strong behavioral responses in pinnipeds in water, but no data exist at higher received levels. Potential Effects of Behavioral Disturbance 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 is limited marine mammal data quantitatively 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. 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’’ E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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. These costs have been documented best in foraging animals, where vigilance has been shown to substantially reduce feeding rates (Saino, 1994; Beauchamp and Livoreil, 1997; Fritz et al., 2002). 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 (for example, multiple surface vessels), or when they co-occur with times that an animal perceives increased risk (for example, when they are giving birth or accompanied by a calf). Most of the published literature, however, suggests that direct approaches will increase the amount of time animals will dedicate to being vigilant. For example, bighorn sheep and Dall’s sheep dedicated more time being vigilant, and less time resting or foraging, when aircraft made direct approaches over them (Frid, 2001; Stockwell et al., 1991). Several authors have established that long-term and intense disturbance stimuli can cause population declines by reducing the body condition of individuals that have been disturbed, followed by reduced reproductive success, reduced survival, or both (Daan et al., 1996; Madsen, 1994; White, 1983). For example, Madsen (1994) reported that pink-footed geese 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 disturbed by all-terrain vehicles (Yarmoloy et al., 1988), caribou disturbed by seismic exploration blasts (Bradshaw et al., 1998), caribou disturbed by low-elevation military jetfights (Luick et al., 1996), and caribou disturbed by low-elevation jet flights (Harrington and Veitch, 1992). Similarly, a study of elk that were VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 disturbed experimentally by pedestrians concluded that the ratio of young to mothers was inversely related to disturbance rate (Phillips and Alldredge, 2000). 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). For example, a study of grizzly bears reported that bears disturbed by hikers reduced their energy intake by an average of 12 kcal/minute (50.2 x 103kJ/ minute), and spent energy fleeing or acting aggressively toward hikers (White et al., 1999). Alternately, Ridgway et al. (2006) reported that increased vigilance in bottlenose dolphins exposed to sound over a 5-day period did not cause any sleep deprivation or stress effects such as changes in cortisol or epinephrine levels. 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 Sharks 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 short period). Last, in a study of northern resident killer whales off PO 00000 Frm 00015 Fmt 4701 Sfmt 4700 46125 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-hour cycle). Substantive behavioral reactions to noise exposure (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). Consequently, a behavioral response lasting less than 1 day and not recurring on subsequent days is not considered particularly 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 that exercise for multiple days or, further, exposed in a manner resulting in a sustained multiple day substantive behavioral responses. In order to understand how the effects of activities may or may not impact stocks and populations 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 changes. 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 (below). As depicted, behavioral and physiological changes can either 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, or they can have indirect and long-term (chronic) effects on vital rates, such as when changes in time/energy budgets or E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46126 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations increased disease susceptibility affect health, which then affects vital rates (New et al., 2014). In addition to outlining this general framework and compiling the relevant literature that supports it, New et al. (2014) have chosen 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 effectively 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 projectspecific risk assessments, they are a critical first step. NMFS is constantly evaluating new science and how to best incorporate it into our decisions. This process involves careful consideration of new data and how it is best interpreted within the context of a given management framework. Since preparation of the proposed rule, NMFS has considered additional studies regarding behavioral responses that are relevant to the proposed activities and energy sources. A recent study by Moore and Barlow (2013) emphasizes 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. In addition, Houser et al., 2013 and Claridge, 2013 were recently published. Houser et al. (2013) performed a controlled exposure study involving California sea lions exposed to a simulated mid-frequency sonar signal. The purpose of this Navy-sponsored study was to determine the probability and magnitude of behavioral responses by California sea lions exposed to differing intensities of simulated midfrequency sonar signals. Houser et al.’s findings are consistent with current scientific studies and criteria development concerning marine mammal reactions to mid-frequency sonar sounds. Claridge’s (2013) Ph.D. thesis investigated the potential effects exposure to mid-frequency active sonar could have on beaked whale demographics. In summary, Claridge suggested that lower reproductive rates observed at the Navy’s Atlantic Undersea Test and Evaluation Center (AUTEC), when compared to a control site, were due to stressors associated with frequent and repeated use of Navy sonar. However, the author noted that there may be other unknown differences between the sites. It is also important to VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 note that there were some relevant shortcomings of this study. For example, all of the re-sighted whales during the 5-year study at both sites were female, which Claridge acknowledged can lead to a negative bias in the abundance estimation. There was also a reduced effort and shorter overall study period at the AUTEC site that failed to capture some of the emigration/immigration trends identified at the control site. Furthermore, Claridge assumed that the two sites were identical and therefore should have equal potential abundances; when in reality, there were notable physical differences. All of the aforementioned studies were considered in NMFS’ determination to issue regulations and associated LOA to the Navy for their proposed activities in the MITT Study Area. Stranding and Mortality When a live or dead marine mammal swims or floats onto shore and becomes ‘‘beached’’ or incapable of returning to sea, the event is termed a ‘‘stranding’’ (Geraci et al., 1999; Perrin and Geraci, 2002; Geraci and Lounsbury, 2005; NMFS, 2007). The legal definition for a stranding within the U.S. 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 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.’’ (16 U.S.C. 1421h). Marine mammals are known to strand for a variety of reasons, such as infectious agents, biotoxicosis, starvation, fishery interaction, ship strike, unusual oceanographic or weather events, sound exposure, or combinations of these stressors sustained concurrently or in series. However, the cause or causes of most strandings are unknown (Geraci et al., 1976; Eaton, 1979, Odell et al., 1980; Best, 1982). Numerous studies suggest that the physiology, behavior, habitat relationships, age, or condition of cetaceans may cause them to strand or might pre-dispose 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 PO 00000 Frm 00016 Fmt 4701 Sfmt 4700 commonly combine to kill an animal or dramatically reduce its fitness, even though one exposure without the other does not produce the same result (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). For reference, between 2001 and 2009, there was an annual average of 1,400 cetacean strandings and 4,300 pinniped strandings along the coasts of the continental U.S. and Alaska (NMFS, 2011). Several sources have published lists of mass stranding events of cetaceans in an attempt to identify relationships between those stranding events and military sonar (Hildebrand, 2004; IWC, 2005; Taylor et al., 2004). For example, based on a review of stranding records between 1960 and 1995, the International Whaling Commission (2005) identified ten mass stranding events of Cuvier’s beaked whales had been reported and one mass stranding of four Baird’s beaked whale. The IWC concluded that, out of eight stranding events reported from the mid-1980s to the summer of 2003, seven had been coincident with the use of tactical midfrequency sonar, one of those seven had been associated with the use of tactical low-frequency sonar, and the remaining stranding event had been associated with the use of seismic airguns. Most of the stranding events reviewed by the International Whaling Commission 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. Between 1960 and 2006, 48 strandings (68 percent) involved beaked whales, three (4 percent) involved dolphins, and 14 (20 percent) involved whale species. Cuvier’s beaked whales were involved in the greatest number of these events (48 or 68 percent), followed by sperm whales (seven or 10 percent), and Blainville’s and Gervais’ beaked whales (four each or 6 percent). Naval activities (not just activities conducted by the U.S. Navy) that might have involved active sonar are reported to have coincided with nine or 10 (13 to 14 percent) of E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations those stranding events. Between the mid-1980s and 2003 (the period reported by the International Whaling Commission), NMFS identified reports of 44 mass cetacean stranding events of which at least seven were coincident with naval exercises that were using MFAS. mstockstill on DSK4VPTVN1PROD with RULES2 Strandings Associated With Impulse Sound 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 5 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 Ocean Beach, California (3 days later and approximately 11.8 mi. [19 km] from Silver Strand where the training event occurred), which might also have been related to this event. Association of the 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 impulse energy (underwater detonation) that caused mortality or injury to a marine mammal. Despite this being a rare occurrence, the Navy has 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 these and other training and testing events are presented in the Mitigation section. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Strandings Associated With MFAS Over the past 16 years, there have been five stranding events coincident with military mid-frequency 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). 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 stranding. A number of other stranding events coincident with the operation of mid-frequency sonar, 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 and only one of these stranding events, the Bahamas (2000), was associated with exercises conducted by the U.S. Navy. 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. This report suggests that the operation of a commercial highpowered 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 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 a suite of mitigation intended to more broadly minimize impacts to marine mammals, the Navy and NMFS have a detailed Stranding Response Plan that outlines reporting, communication, and response protocols intended both to minimize the impacts of, and enhance the analysis of, any PO 00000 Frm 00017 Fmt 4701 Sfmt 4700 46127 potential stranding in areas where the Navy operates. 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 apparent abnormalities or wounds were found. Examination of photos of the animals, taken soon after their death, revealed that the eyes of at least four of the individuals were bleeding. Photos were taken soon after their death (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 were 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 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 history), 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, E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46128 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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 hours 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-hr 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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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, Spain (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 PO 00000 Frm 00018 Fmt 4701 Sfmt 4700 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 nm (65 km) and at least 10 nm (19 km) 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 E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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 near proximity of an international naval exercise that utilized MFAS and involved numerous surface warships and several submarines. Strandings began about 4 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, six 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 Canary Islands stranding event lead to the hypothesis that the presence of disseminated and widespread gas VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 bubbles and fat emboli were indicative of nitrogen bubble formation, similar to what might be expected in decompression sickness (Jepson et al., ´ ´ 2003; Fernandez et al., 2005; Fernandez et al., 2012). Hanalei Bay (2004)—On July 3 and 4, 2004, approximately 150 to 200 melonheaded whales occupied the shallow waters of the Hanalei Bay, Kaua’i, 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 U.S. 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 PO 00000 Frm 00019 Fmt 4701 Sfmt 4700 46129 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 9 hours total between the hours of 1:15 p.m. and 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 use, the animals were herded out of the Bay. While causation of this stranding event may never be unequivocally determined, NMFS consider 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 E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46130 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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 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 (but was similar to the events at Palmyra), 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. Since that time there have been two ‘‘out of habitat’’ or ‘‘near mass strandings’’ of VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 melon-headed whales in the Philippines (Aragones et al., 2010). Pictures of one of these events depict grouping behavior like that displayed at Hanalei Bay in July 2004. No naval sonar activity was noted it the area, although it was suspected by the authors, based on personal communication with a government fisheries representative, that dynamite blasting in the area may have occurred within the days prior to one of the events (Aragones et al., 2010). Although melon-headed whales entering embayments may be infrequent and rare, there is precedent for this type of occurrence on other occasions in the absence of naval activity. 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 Mojacar (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 (these later died). 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 Mojacar 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 nm (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) were operating MFAS in the same area over extended periods of time (in this case, 20 hours) in close proximity; and PO 00000 Frm 00020 Fmt 4701 Sfmt 4700 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). Association Between Mass Stranding Events and Exposure to MFAS Several authors have noted similarities between some of these stranding incidents: They occurred in islands or archipelagoes with deep water nearby, several appeared to have been associated with acoustic waveguides like surface ducting, and the sound fields created by ships transmitting MFAS (Cox et al., 2006, D’Spain et al., 2006). Although Cuvier’s beaked whales have been the most common species involved in these stranding events (81 percent of the total number of stranded animals), other beaked whales (including Mesoplodon europeaus, M. densirostris, and Hyperoodon ampullatus) comprise 14 percent of the total. Other species (Stenella coeruleoalba, Kogia breviceps and Balaenoptera acutorostrata) have stranded, but in much lower numbers and less consistently than beaked whales. Based on the evidence available, however, NMFS cannot determine whether (a) Cuvier’s beaked whale is more prone to injury from high-intensity sound than other species; (b) their behavioral responses to sound makes them more likely to strand; or (c) they are more likely to be exposed to MFAS than other cetaceans (for reasons that remain unknown). Because the association between active sonar exposures and marine mammals mass stranding events is not consistent— some marine mammals strand without being exposed to sonar and some sonar transmissions are not associated with marine mammal stranding events despite their co-occurrence—other risk factors or a grouping of risk factors probably contribute to these stranding events. Behaviorally Mediated Responses to MFAS That May Lead to Stranding Although the confluence of Navy MFAS with the other contributory factors noted in the 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 understood, and there is uncertainty regarding the ordering of effects that led to the stranding. It is unclear whether beaked E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 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 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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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). 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 kilometers) 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 (also see 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 Ziphius), perhaps as a consequence of an extended avoidance reaction to sonar PO 00000 Frm 00021 Fmt 4701 Sfmt 4700 46131 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 ascent 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 midfrequency range sonar (Jepson et al., ´ 2003; Fernandez et al., 2005; Fernandez 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 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). The probability of flight responses should 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 E:\FR\FM\03AUR2.SGM 03AUR2 46132 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES2 closer to the ground (Steidl and Anthony, 1996). Despite the many theories involving bubble formation (both as a direct cause of injury (see Acoustically Mediated Bubble Growth Section) and an indirect cause of stranding (See Behaviorally Mediated Bubble Growth Section)), 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. Impulsive 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). In addition, gascontaining organs including the nasal sacs, larynx, pharynx, trachea, and lungs may be damaged by compression/ expansion caused by the oscillations of the blast gas bubble (Reidenberg and Laitman, 2003). Intestinal walls can VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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 susceptible 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). Sound-related trauma can be lethal or sublethal. 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). There have been fewer studies addressing the behavioral effects of explosives on marine mammals compared to MFAS/HFAS. However, though the nature of the sound waves emitted from an explosion are different (in shape and rise time) from MFAS/ HFAS, NMFS still anticipates the same sorts of behavioral responses to result from repeated explosive detonations (a smaller range of likely less severe responses (i.e., not rising to the level of MMPA harassment) would be expected to occur as a result of exposure to a single explosive detonation that was not powerful enough or close enough to the animal to cause TTS or injury). 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 PO 00000 Frm 00022 Fmt 4701 Sfmt 4700 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 U.S. 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 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 5–8 km from a seismic array during observational studies and controlled exposure experiments in western Australia (McCauley, 1998; 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. Seismic pulses at average received levels of 131 dB re 1 micropascal squared 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). These studies demonstrate that even low levels of noise received far from the noise source can induce behavioral responses. Madsen et al. (2006) and Miller et al. (2009) tagged and monitored eight sperm whales in the Gulf of Mexico exposed to seismic airgun surveys. Sound sources were from approximately 2 to 7 nm away from the whales and based on multipath propagation received levels were as high as 162 dB SPL re 1 mPa with energy content greatest between 0.3 and 3.0 kHz (Madsen, 2006). The whales showed no horizontal avoidance, although the whale that was approached most closely had an extended resting period and did not resume foraging until the airguns had ceased firing (Miller et al., 2009). The remaining whales continued to E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES2 execute foraging dives throughout exposure; however, swimming movements during foraging dives were 6 percent lower during exposure than control periods, suggesting subtle effects of noise on foraging behavior (Miller et al., 2009). Captive bottlenose dolphins sometimes vocalized after an exposure to impulse sound from a seismic watergun (Finneran et al., 2010a). A review of behavioral reactions by pinnipeds to impulse noise can be found in Richardson et al. (1995) and Southall et al. (2007). Blackwell et al. (2004) observed that ringed seals exhibited little or no reaction to pipedriving noise with mean underwater levels of 157 dB re 1 mPa rms and in air levels of 112 dB re 20 mPa, suggesting that the seals had habituated to the noise. In contrast, captive California sea lions avoided sounds from an impulse source at levels of 165–170 dB re 1 mPa (Finneran et al., 2003b). Experimentally, ¨ Gotz and Janik (2011) tested underwater, startle responses to a startling sound (sound with a rapid rise time and a 93 dB sensation level [the level above the animal’s threshold at that frequency]) and a non-startling sound (sound with the same level, but with a slower rise time) in wildcaptured gray seals. The animals exposed to the startling treatment avoided a known food source, whereas animals exposed to the non-startling treatment did not react or habituated during the exposure period. The results of this study highlight the importance of the characteristics of the acoustic signal in an animal’s response of habituation. Vessels Commercial and Navy ship strikes of cetaceans can cause major wounds, which may lead to the death of the animal. An animal at the surface could be struck directly by a vessel, a surfacing animal could hit the bottom of a vessel, or an animal just below the surface could be cut by a vessel’s propeller. The severity of injuries typically depends on the size and speed of the vessel (Knowlton and Kraus, 2001; Laist et al., 2001; Vanderlaan and Taggart, 2007). The most vulnerable marine mammals 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., the sperm whale). In addition, some baleen whales, such as the North Atlantic right whale, 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. Smaller marine mammals (e.g., bottlenose dolphin) move quickly VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 through the water column and are often seen riding the bow wave of large ships. Marine mammal responses to vessels may include avoidance and changes in dive pattern (NRC, 2003). An examination of all known ship strikes from all shipping sources (civilian and military) indicates vessel speed is a principal factor in whether a vessel strike results in death (Knowlton and Kraus, 2001; Laist et al., 2001; Jensen and Silber, 2003; Vanderlaan and Taggart, 2007). In assessing records in which vessel speed was known, Laist et al. (2001) found a direct relationship between the occurrence of a whale strike and the speed of the vessel involved in the collision. The authors concluded that most deaths occurred when a vessel was traveling in excess of 13 knots. Jensen and Silber (2003) detailed 292 records of known or probable ship strikes of all large whale species from 1975 to 2002. Of these, vessel speed at the time of collision was reported for 58 cases. Of these cases, 39 (or 67 percent) resulted in serious injury or death (19 of those resulted in serious injury as determined by blood in the water, propeller gashes or severed tailstock, and fractured skull, jaw, vertebrae, hemorrhaging, massive bruising or other injuries noted during necropsy and 20 resulted in death). Operating speeds of vessels that struck various species of large whales ranged from 2 to 51 knots. The majority (79 percent) of these strikes occurred at speeds of 13 knots or greater. The average speed that resulted in serious injury or death was 18.6 knots. Pace and Silber (2005) found that the probability of death or serious injury increased rapidly with increasing vessel speed. Specifically, the predicted probability of serious injury or death increased from 45 to 75 percent as vessel speed increased from 10 to 14 knots, and exceeded 90 percent at 17 knots. Higher speeds during collisions result in greater force of impact and also appear to increase the chance of severe injuries or death. While modeling studies have suggested that hydrodynamic forces pulling whales toward the vessel hull increase with increasing speed (Clyne, 1999; Knowlton et al., 1995), this is inconsistent with Silber et al. (2010), which demonstrated that there is no such relationship (i.e., hydrodynamic forces are independent of speed). The Jensen and Silber (2003) report notes that the database represents a minimum number of collisions, because the vast majority probably goes undetected or unreported. In contrast, Navy vessels are likely to detect any strike that does occur, and they are PO 00000 Frm 00023 Fmt 4701 Sfmt 4700 46133 required to report all ship strikes involving marine mammals. Overall, the percentages of Navy traffic relative to overall large shipping traffic are very small (on the order of 2 percent). There are no records of any Navy vessel strikes to marine mammals during training or testing activities in the MITT Study Area. There have been Navy strikes of large whales in areas outside the Study Area, such as Hawaii and Southern California. However, these areas differ significantly from the Study Area given that both Hawaii and Southern California have a much higher number of Navy vessel activities and much higher densities of large whales. Other efforts have been undertaken to investigate the impact from vessels (both whale-watching and general vessel traffic noise) and demonstrated impacts do occur (Bain, 2002; Erbe, 2002; Lusseau, 2009; Williams et al., 2006, 2009, 2011b, 2013, 2014a, 2014b; Noren et al., 2009; Read et al., 2014; Rolland et al., 2012; Pirotta et al., 2015). This body of research for the most part has investigated impacts associated with the presence of chronic stressors, which differ significantly from generally intermittent Navy training and testing activities. For example, in an analysis of energy costs to killer whales, Williams et al. (2009) suggested that whalewatching in the 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) recently reported on research in the Salish Sea 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. Mitigation Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the ‘‘permissible methods of taking pursuant to such activity, and other 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.’’ NMFS’ duty under this ‘‘least practicable adverse impact’’ standard is to prescribe mitigation reasonably designed to minimize, to the extent practicable, any adverse populationlevel impacts, as well as habitat impacts. While population-level E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46134 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations impacts are minimized by reducing impacts on individual marine mammals, not all takes have a reasonable potential for translating to population-level impacts. NMFS’ objective under the ‘‘least practicable adverse impact’’ standard is to design mitigation targeting those impacts on individual marine mammals that are reasonably likely to contribute to adverse population-level effects. The NDAA of 2004 amended the MMPA as it relates to military-readiness activities and the ITA process such that ‘‘least practicable adverse impact’’ shall include consideration of personnel safety, practicality of implementation, and impact on the effectiveness of the ‘‘military readiness activity.’’ The training and testing activities described in the Navy’s LOA application are considered military readiness activities. In Conservation Council for Hawaii v. National Marine Fisheries Service, No. 1:13–cv–00684 (D. Hawaii March 31, 2015), the court stated that NMFS ‘‘appear[s] to think that [it] satisf[ies] the statutory ‘least practicable adverse impact’ requirement with a ‘negligible impact’ finding.’’ In light of the court’s decision, we take this opportunity to make clear our position that the ‘‘negligible impact’’ and ‘‘least practicable adverse impact’’ requirements are distinct, even though the focus of both is on population-level impacts. A population-level impact is an impact on the population numbers (survival) or growth and reproductive rates (recruitment) of a particular marine mammal species or stock. As we noted in the preamble to our general MMPA implementing regulations, not every population-level impact violates the negligible impact requirement. As we explained, 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 . . . [T]he key factor is the significance of the level of impact on rates of recruitment or survival. Only insignificant impacts on long-term population levels and trends can be treated as negligible.’’ See 54 FR 40338, 40341–42 (Sept 29, 1989). Nevertheless, while insignificant impacts on population numbers or growth rates may satisfy the negligible impact requirement, such impacts still VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 must be mitigated, to the extent practicable, under the ‘‘least practicable adverse impact’’ requirement. Thus, the negligible impact and least practicable adverse impact requirements are clearly distinct, even though both focus on population-level effects. As explained in the proposed rule, any mitigation measure(s) prescribed by NMFS should be able to accomplish, have a reasonable likelihood of accomplishing (based on current science), or contribute to accomplishing one or more of the general goals listed below: a. Avoid or minimize injury or death of marine mammals wherever possible (goals b, c, and d may contribute to this goal). b. Reduce the numbers of marine mammals (total number or number at biologically important time or location) exposed to received levels of MFAS/ HFAS, underwater detonations, or other activities expected to result in the take of marine mammals (this goal may contribute to a, above, or to reducing harassment takes only). c. Reduce the number of times (total number or number at biologically important time or location) individuals would be exposed to received levels of MFAS/HFAS, underwater detonations, or other activities expected to result in the take of marine mammals (this goal may contribute to a, above, or to reducing harassment takes only). d. Reduce the intensity of exposures (either total number or number at biologically important time or location) to received levels of MFAS/HFAS, underwater detonations, or other activities expected to result in the take of marine mammals (this goal may contribute to a, above, or to reducing the severity of harassment takes only). e. Avoid or minimize adverse effects to marine mammal habitat, paying special attention to the food base, activities that block or limit passage to or from biologically important areas, permanent destruction of habitat, or temporary destruction/disturbance of habitat during a biologically important time. f. For monitoring directly related to mitigation—increase the probability of detecting marine mammals, thus allowing for more effective implementation of the mitigation (shutdown zone, etc.). Our final evaluation of measures that meet one or more of the above goals includes consideration of the following factors in relation to one another: The PO 00000 Frm 00024 Fmt 4701 Sfmt 4700 manner in which, and the degree to which, the successful implementation of the mitigation measures is expected to reduce population-level impacts to marine mammal species and stocks and impacts to their habitat; the proven or likely efficacy of the measures; and the practicability of the suite of measures for applicant implementation, including consideration of personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. NMFS reviewed the proposed activities and the suite of proposed mitigation measures as described in the Navy’s LOA application to determine if they would result in the least practicable adverse effect on marine mammals. NMFS described the Navy’s proposed mitigation measures in detail in the proposed rule (79 FR 15388, March 19, 2014; pages 15414–15422), and they have not changed. NMFS worked with the Navy in the development of the Navy’s initially proposed measures, and they are informed by years of experience and monitoring. As described in the Mitigation Conclusions below and in responses to comments, and in the MITT FEIS/OEIS, additional measures were considered and analyzed, but ultimately not chosen for implementation. Below are the mitigation measures as agreed upon by the Navy and NMFS. For additional details regarding the Navy’s mitigation measures, see Chapter 5 in the MITT FEIS/OEIS. • At least one Lookout during applicable training and testing activities; • Mitigation zones ranging from 70 yards (yd) (64 m) to 2.5 nautical miles (nm) during applicable activities that involve the use of impulse and nonimpulse sources to avoid or reduce the potential for onset of the lowest level of injury, PTS, out to the predicted maximum range (Tables 6 and 7); • Mitigation zones of 500 yd (457 m) for whales and 200 yd (183 m) for all other marine mammals (except bow riding dolphins) during vessel movement, and a mitigation zone of 250 yd (229 m) for marine mammals during use of towed in-water devices being towed from manned platforms; and • Mitigation zones ranging from 200 yd (183 m) to 1,000 yd (914 m) during activities that involve the use of nonexplosive practice munitions. E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 46135 TABLE 6—PREDICTED RANGES TO TTS, PTS, AND RECOMMENDED MITIGATION ZONES Activity category Predicted average (longest) range to TTS Bin (representative source)* Predicted average (longest) range to PTS Predicted maximum range to PTS Recommended mitigation zone Non-Impulse Sound Low-Frequency and Hull-Mounted MidFrequency Active Sonar. Page 83 .................... 3,281 yd (3.5 km) for one ping. Page 83 .................... 100 yd (91 m) for one ping. Not Applicable ........... LF4 (low-frequency sonar) **. High-Frequency and Non-Hull Mounted Mid-Frequency Active Sonar. MF1 (SQS–53 ASW hull-mounted sonar). 3,821 yd. (3.5 km) for one ping. 100 yd. (91 m) for one ping. Not Applicable ........... 6 dB power down at 1,000 yd. (914 m); 4 dB power down at 500 yd. (457 m); and shutdown at 200 yd. (183 m). 200 yd. (183 m).** MF4 (AQS–22 ASW dipping sonar). 230 yd. (210 m) for one ping. 20 yd. (18 m) for one ping. Not Applicable ........... 200 yd. (183 m). Explosive and Impulse Sound Improved Extended Echo Ranging Sonobuoys. Explosive Sonobuoys using 0.6–2.5 lb. NEW. Anti-Swimmer Grenades. E4 (Explosive sonobuoy). 434 yd. (397 m) ........ 156 yd. (143 m) ........ 563 yd. (515 m) ........ 600 yd. (549 m). E3 (Explosive sonobuoy). 290 yd. (265 m) ........ 113 yd. (103 m) ........ 309 yd. (283 m) ........ 350 yd. (320 m). E2 (Up to 0.5 lb. NEW). 190 yd. (174 m) ........ 83 yd. (76 m) ............ 182 yd. (167 m) ........ 200 yd. (183 m). Mine Countermeasure and Neutralization Activities Using Positive Control Firing Devices. Mine Neutralization Diver-Placed Mines Using Time-Delay Firing Devices. Gunnery Exercises— Small- and MediumCaliber (Surface Target). Gunnery Exercises— Large-Caliber (Surface Target). Missile Exercises up to 250 lb. NEW (Surface Target). Missile Exercises > 250 to 500 lb. NEW (Surface Target). Bombing Exercises .... mstockstill on DSK4VPTVN1PROD with RULES2 Torpedo (Explosive) Testing. Sinking Exercises ....... NEW dependent (see Table 7). E6 (Up to 20 lb. NEW). 407 yd. (372 m) ........ 98 yd. (90 m) ............ 102 yd. (93 m) .......... 1,000 yd. (914 m). E2 (40 mm projectile) 190 yd. (174 m) ........ 83 yd. (76 m) ............ 182 yd. (167 m) ........ 200 yd. (183 m). E5 (5 in. projectiles at the surface ***). 453 yd. (414 m) ........ 186 yd. (170 m) ........ 526 yd. (481 m) ........ 600 yd. (549 m). E9 (Maverick missile) 949 yd. (868 m) ........ 398 yd. (364 m) ........ 699 yd. (639 m) ........ 900 yd. (823 m). E10 (Harpoon missile). 1,832 yd. (1,675 m) .. 731 yd. (668 m) ........ 1,883 yd. (1,721 m) .. 2,000 yd. (1.8 km). E12 (MK–84 2,000 lb. bomb). E11 (MK–48 torpedo) 2,513 yd. (2.3 km) .... 991 yd. (906 m) ........ 2,474 yd. (2.3 km) .... 1,632 yd. (1.5 km) .... 697 yd. (637 m) ........ 2,021 yd. (1.8 km) .... 2,500 yd. (2.3 km).**** 2,100 yd. (1.9 km).\ E12 (Various sources up to the MK–84 2,000 lb. bomb). 2,513 yd. (2.3 km) .... 991 yd. (906 m) ........ 2,474 yd. (2.3 km) .... 2.5 nm.**** ASW = anti-submarine warfare, km = kilometers, lb.= pound(s), m = meters, mm = millimeters, NEW = net explosive weight, nm = nautical miles, PTS = Permanent Threshold Shift, TTS = Temporary Threshold Shift, yd. = yards * This table does not provide an inclusive list of source bins; bins presented here represent the source bin with the largest range to effects within the given activity category. ** The representative source bin and mitigation zone applies to sources that cannot be powered down (e.g., bins LF4 and LF5). *** The representative source bin E5 has different range to effects depending on the depth of activity occurrence (at the surface or at various depths). **** Recommended mitigation zones are larger than the modeled injury zones to account for multiple types of sources or charges being used. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 PO 00000 Frm 00025 Fmt 4701 Sfmt 4700 E:\FR\FM\03AUR2.SGM 03AUR2 46136 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations TABLE 7—PREDICTED RANGES TO EFFECTS AND MITIGATION ZONE RADIUS FOR MINE COUNTERMEASURE AND NEUTRALIZATION ACTIVITIES USING POSITIVE CONTROL FIRING DEVICES Charge size net explosive weight (bins) General mine countermeasure and neutralization activities using positive control firing devices * Predicted average range to TTS Predicted average range to PTS Predicted maximum range to PTS 434 yd (474 m) 197 yd (180 m) 563 yd (515 m) 525 yd (480 m) 204 yd (187 m) 766 yd (700 m) 288 yd (263 m) 2.5–5 lb. (1.2–2.3 kg) (E4) ........................ 5–10 lb. (2.7–4.5 kg) (E5) ........................ >10–20 lb. (5–9.1 kg) (E6) ........................ Mine countermeasure and neutralization activities using diver placed charges under positive control ** Predicted average range to TTS Predicted average range to PTS Predicted maximum range to PTS 600 yd. (549 m) 545 yd (498 m) 169 yd (155 m) 301 yd (275 m) 350 yd (320 m). 649 yd (593 m) 800 yd (732 m) 587 yd (537 m) 203 yd (185 m) 464 yd (424 m) 500 yd (457 m). 648 yd (593 m) 800 yd (732 m) 647 yd (592 m) 232 yd (212 m) 469 yd (429 m) 500 yd (457 m) Recommended mitigation zone Recommended mitigation zone PTS: permanent threshold shift; TTS: temporary threshold shift. * These mitigation zones are applicable to all mine countermeasure and neutralization activities conducted in all locations specified in Chapter 2 of the Navy’s LOA application. ** These mitigation zones are only applicable to mine countermeasure and neutralization activities involving the use of diver placed charges. These activities are conducted in shallow-water and the mitigation zones are based only on the functional hearing groups with species that occur in these areas (mid-frequency cetaceans and sea turtles). Stranding Response Plan NMFS and the Navy developed a Stranding Response Plan for MIRC in 2010 as part of the incidental take authorization process. In addition, Regional Stranding Implementation Assistance Plans for MIRC were established in 2011 per a Navy-NMFS MOU. The Stranding Response Plan is specifically intended to outline the applicable requirements in the event that a marine mammal stranding is reported in the MIRC during a major training exercise. NMFS considers all plausible causes within the course of a stranding investigation and these plans in no way presume that any strandings in a Navy range complex are related to, or caused by, Navy training and testing activities, absent a determination made during investigation. The plans are designed to address mitigation, monitoring, and compliance. The Navy worked with NMFS to refine these plans for the new MITT Study Area (to include regionally specific plans that include more logistical detail) and these revised plans are available here: https:// www.nmfs.noaa.gov/pr/permits/ incidental/. Modifications to the Stranding Response Plan may also be made through the adaptive management process. mstockstill on DSK4VPTVN1PROD with RULES2 Mitigation Conclusions NMFS has carefully evaluated the Navy’s proposed mitigation measures— many of which were developed with NMFS’ input during the first phase of authorizations—and considered a range of other measures in the context of ensuring that NMFS prescribes the means of effecting the least practicable adverse impact on the affected marine mammal species and stocks and their habitat. Based on our evaluation of the VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Navy’s proposed measures, as well as other measures considered by NMFS, NMFS has determined that the Navy’s proposed mitigation measures (especially when the adaptive management component is taken into consideration (see Adaptive Management, below)) are adequate means of effecting the least practicable adverse impacts on marine mammals species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, while also considering personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. Monitoring Section 101(a)(5)(A) of the MMPA states that in order to issue an ITA 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 LOAs 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. NMFS provided an overview of Navy monitoring and research, highlighted recent findings, and explained the Navy’s new approach to monitoring in the proposed rule (79 FR 15388; pages 15422–15426). Below is a summary of the Navy’s Integrated Comprehensive Monitoring Program (ICMP) and the Navy’s Strategic Planning Process for Marine Species Monitoring. PO 00000 Frm 00026 Fmt 4701 Sfmt 4700 Integrated Comprehensive Monitoring Program The Navy’s ICMP is intended to coordinate 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. Although the ICMP does not specify actual monitoring field work or projects, it does establish top-level goals that have been developed in coordination with NMFS. As the ICMP is implemented, detailed and specific studies will be developed which support the Navy’s 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 one or more of the following top-level goals: • An increase in our understanding of the likely occurrence of marine mammals and/or ESA-listed marine species in the vicinity of the action (i.e., presence, abundance, distribution, and/ or density of species); • An increase in our understanding of the nature, scope, or context of the likely exposure of marine mammals and/or ESA-listed species to any of the potential stressor(s) associated with the action (e.g., tonal and impulsive sound), through better understanding of one or more of the following: (1) the action and the environment in which it occurs (e.g., sound source characterization, propagation, and ambient noise levels); E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations (2) the affected species (e.g., life history or dive patterns); (3) the likely cooccurrence of marine mammals and/or ESA-listed marine species with the action (in whole or part) associated with specific adverse effects, and/or; (4) the likely biological or behavioral context of exposure to the stressor for the marine mammal and/or ESA-listed marine species (e.g., age class of exposed animals or known pupping, calving or feeding areas); • An increase in our 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 our 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 effects on annual rates of recruitment or survival); • An increase in our understanding of the effectiveness of mitigation and monitoring measures; • A better understanding and record of the manner in which the authorized entity complies with the ITA and Incidental Take Statement; • An increase in the probability of detecting marine mammals (through improved technology or methods), both specifically within the safety zone (thus allowing for more effective implementation of the mitigation) and in general, to better achieve the above goals; and • A reduction in the adverse impact of activities to the least practicable level, as defined in the MMPA. Monitoring addresses the ICMP toplevel goals through a collection of specific regional and ocean basin studies based on scientific objectives. Quantitative metrics of monitoring effort (e.g., 20 days of aerial surveys) are not a specific requirement. The adaptive management process and reporting requirements serve as the basis for evaluating performance and compliance, primarily considering the quality of the work and results produced, as well as peer review and publications, and public dissemination of information, reports, and data. Details of the ICMP and all MIRC monitoring reports are available online (https://www.navymarinespecies monitoring.us/). VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Strategic Planning Process for Marine Species Monitoring The Navy also developed the Strategic Planning Process for Marine Species Monitoring, which 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 top-level goals, a conceptual framework incorporating a progression of knowledge, and consultation with a Scientific Advisory Group and other regional experts. The Strategic Planning Process for Marine Species Monitoring has been used to set intermediate scientific objectives, identify potential species of interest at a regional scale, and evaluate and select specific monitoring projects to fund or continue supporting for a given fiscal year. This process would also address 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. The Strategic Planning Process for Marine Species Monitoring is also available online (https://www.navy marinespeciesmonitoring.us/). Past Monitoring in the MITT Study Area NMFS has received multiple years’ worth of annual exercise and monitoring reports addressing active sonar use and explosive detonations within the MIRC 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 Study Area. The Navy’s annual exercise and monitoring reports may be viewed at: https://www.nmfs.noaa.gov/pr/ permits/incidental/ and https:// www.navymarinespeciesmonitoring.us. NMFS’ summary of the Navy’s annual monitoring reports was included in the proposed rule (79 FR 15388, March 19, 2014; pages 15423–15424). The Navy has since submitted to NMFS the 5-year Comprehensive Monitoring Report for MIRC, which is available at: https:// www.nmfs.noaa.gov/pr/permits/ incidental/. Proposed Monitoring for the MITT Study Area Based on discussions between the Navy and NMFS, future monitoring should address the ICMP top-level goals through a collection of specific regional and ocean basin studies based on scientific objectives. Monitoring would follow the strategic planning process PO 00000 Frm 00027 Fmt 4701 Sfmt 4700 46137 and conclusions from adaptive management review by shifting from applying quantitative effort-based metrics, and instead demonstrating progress on the goals of specific scientific monitoring questions. The adaptive management process and reporting requirements would serve as the basis for evaluating performance and compliance, primarily considering the quality of the work and results produced, as well as peer review and publications, and public dissemination of information, reports, and data. The strategic planning process would be used to set intermediate scientific objectives, identify potential species of interest at a regional scale, and evaluate and select specific monitoring projects to fund or continue supporting for a given fiscal year. The strategic planning process would also address 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. The Scientific Advisory Group (SAG) confirmed the Navy/NMFS decision made in 2009 that because so little is known about species occurrence in this area, the priority for the MIRC should be establishing basic marine mammal occurrence. Passive acoustic monitoring, small boat surveys, biopsy sampling, satellite tagging, and photoidentification are all appropriate methods for evaluating marine mammal occurrence and abundance in the MITT Study Area. Fixed acoustic monitoring and development of local expertise ranked highest among the SAG’s recommended monitoring methods for the area. There is an especially high level of return for monitoring around the Mariana Islands because so little is currently known about this region. Specific monitoring efforts would result from future Navy/NMFS monitoring program management. A more detailed description of the Navy’s planned projects starting in 2015 (and some continuing from previous years) is available at the Navy’s Marine Species Monitoring web portal: https:// www.navymarinespeciesmonitoring.us/. The Navy will update the status of its monitoring program and funded projects through their Marine Species Monitoring web portal. NMFS will provide one public comment period on the Navy’s monitoring program during the 5-year regulations. At this time, the public will have an opportunity (likely in the second or third year) to comment specifically on the Navy’s MITT monitoring projects and data collection E:\FR\FM\03AUR2.SGM 03AUR2 46138 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES2 to date, as well as planned projects for the remainder of the regulations. Through the adaptive management process (including annual meetings), the Navy will coordinate with NMFS and the Marine Mammal Commission (Commission) to review and provide input for projects that will meet the scientific objectives that are used to guide development of individual monitoring projects. The adaptive management process will continue to serve as the primary venue for both NMFS and the Commission to provide input on the Navy’s monitoring program, including ongoing work, future priorities, and potential new projects. The Navy will continue to submit annual monitoring reports to NMFS as part of the MITT rulemaking and LOA requirements. Each annual report will contain a section describing the adaptive management process and summarize the Navy’s anticipated monitoring projects for the next reporting year. Following annual report submission to NMFS, the final rule language mandates a 3-month NMFS review prior to each report being finalized. This will provide ample time for NMFS and the Commission to comment on the next year’s planned projects as well as ongoing regional projects or proposed new starts. Comments will be received by the Navy prior to the annual adaptive management meeting to facilitate a meaningful and productive discussion. NMFS and the Commission will also have the opportunity for involvement at the annual monitoring program science review meetings and/or regional Scientific Advisory Group meetings. This will help NMFS and the Commission stay informed and understand the scientific considerations and limitations involved with planning and executing various monitoring projects. Ongoing Navy Research The Navy is one of the world’s leading organizations in assessing the effects of human activities on the marine environment, and provides a significant amount of funding and support to marine research, outside of the monitoring required by their incidental take authorizations. They also develop approaches to ensure that these resources are minimally impacted by current and future Navy operations. Navy scientists work cooperatively with other government researchers and scientists, universities, industry, and non-governmental conservation organizations in collecting, evaluating, and modeling information on marine resources, including working towards a VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 better understanding of marine mammals and sound. From 2004 to 2014, the Navy has provided over $250 million for marine species research. The Navy sponsors 70 percent of all U.S. research concerning the effects of human-generated sound on marine mammals and 50 percent of such research conducted worldwide. Major topics of Navy-supported marine species research directly applicable to proposed activities within the MITT Study Area include the following: • Better understanding of marine species distribution and important habitat areas; • Developing methods to detect and monitor marine species before, during, and after training and testing activities; • Better understanding the impacts of sound on marine mammals, sea turtles, fish, and birds; and • Developing tools to model and estimate potential impacts of sound. It is imperative that the Navy’s research and development (R&D) efforts related to marine mammals are conducted in an open, transparent manner with validated study needs and requirements. The goal of the Navy’s R&D program is to enable collection and publication of scientifically valid research as well as development of techniques and tools for Navy, academic, and commercial use. The two Navy organizations that account for most funding and oversight of the Navy marine mammal research program are the Office of Naval Research (ONR) Marine Mammals and Biology Program, and the Office of the Chief of Naval Operations (CNO) Energy and Environmental Readiness Division (N45) Living Marine Resources (LMR) Program. The primary focus of these programs has been on understanding the effects of sound on marine mammals, including physiological, behavioral and ecological effects. The ONR Marine Mammals and Biology Program supports basic and applied research and technology development related to understanding the effects of sound on marine mammals, including physiological, behavioral, ecological, and populationlevel effects. Current program thrusts include: • Monitoring and detection; • Integrated ecosystem research including sensor and tag development; • Effects of sound on marine life including hearing, behavioral response studies, diving and stress physiology, and Population Consequences of Acoustic Disturbance (PCAD); and • Models and databases for environmental compliance. PO 00000 Frm 00028 Fmt 4701 Sfmt 4700 To manage some of the Navy’s marine mammal research programmatic elements, OPNAV N45 developed in 2011 a Living Marine Resources (LMR) Research and Development Program (www.lmr.namy.mil). The mission of the LMR program is to develop, demonstrate, and assess information and technology solutions to protect living marine resources by minimizing the environmental risks of Navy at-sea training and testing activities while preserving core Navy readiness capabilities. This mission is accomplished by: • Improving knowledge of the status and trends of marine species of concern and the ecosystems of which they are a part; • Developing the scientific basis for the criteria and thresholds to measure the effects of Navy generated sound; • Improving understanding of underwater sound and sound field characterization unique to assessing the biological consequences resulting from underwater sound (as opposed to tactical applications of underwater sound or propagation loss modeling for military communications or tactical applications); and • Developing technologies and methods to monitor and, where possible, mitigate biologically significant consequences to living marine resources resulting from naval activities, emphasizing those consequences that are most likely to be biologically significant. The program is focused on three primary objectives that influence program management priorities and directly affect the program’s success in accomplishing its mission: 1. Collect, Validate, and Rank R&D Needs: Expand awareness of R&D program opportunities within the Navy marine resource community to encourage and facilitate the submittal of well-defined and appropriate needs statements. 2. Address High Priority Needs: Ensure that program investments and the resulting projects maintain a direct and consistent link to the defined user needs. 3. Transition Solutions and Validate Benefits: Maximize the number of program-derived solutions that are successfully transitioned to the Fleet and system commands. The LMR program primarily invests in the following areas: • Developing Data to Support Risk Threshold Criteria; • Improved Data Collection on Protected Species, Critical Habitat within Navy Ranges; E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations • New Monitoring and Mitigation Technology Demonstrations; • Database and Model Development; and • Education and Outreach, Emergent Opportunities. LMR currently supports the Marine Mammal Monitoring on Ranges program at the Pacific Missile Range Facility on Kauai and, along with ONR, the multiyear Southern California Behavioral Response Study (https://www.socalbrs.org). This type of research helps in understanding the marine environment and the effects that may arise from underwater noise in oceans. mstockstill on DSK4VPTVN1PROD with RULES2 Adaptive Management Although substantial improvements have been made in our understanding of the effects of Navy training and testing activities (e.g., sonar, underwater detonations) on marine mammals, the science in this field is evolving fairly quickly. These circumstances make the inclusion of an adaptive management component both valuable and necessary within the context of 5-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 are appropriate. NMFS and the Navy would meet to discuss the monitoring reports, Navy R&D developments, and current science and whether mitigation or monitoring modifications 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 reducing adverse effects to marine mammals and if the measures are practicable. The following are some of the possible sources of applicable data to be considered through the adaptive management process: (1) Results from monitoring and exercises reports, as required by MMPA authorizations; (2) compiled results of Navy funded R&D 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 LOA. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Reporting In order to issue an ITA 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. NMFS described the proposed Navy reporting requirements in the proposed rule (79 FR 15388, March 19, 2014; page 15426). 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 and NMFS’ Web site: https:// www.nmfs.noaa.gov/pr/permits/ incidental/. There are several different reporting requirements that are further detailed in the regulatory text at the end of this document and summarized below. General Notification of Injured or Dead Marine Mammals Navy personnel would ensure that NMFS (the appropriate Regional Stranding Coordinator) is notified immediately (or as soon as clearance procedures allow) if an injured or dead marine mammal is found during or shortly after, and in the vicinity of, any Navy training exercise utilizing midfrequency active sonar, high-frequency active sonar, or underwater explosive detonations. The Navy would provide NMFS with species identification or a description of the animal(s), the condition of the animal(s) (including carcass condition if the animal is dead), location, time of first discovery, observed behaviors (if alive), and photographs or video (if available). The MITT Stranding Response Plan contains further reporting requirements for specific circumstances (https:// www.nmfs.noaa.gov/pr/permits/ incidental/). Vessel Strike Since the proposed rule, NMFS has added the following language to address monitoring and reporting measures specific to vessel strike. Most of this language comes directly from the Stranding Response Plan. This section has also been included in the regulatory text at the end of this document. Vessel strike during Navy training and testing activities in the Study Area is not anticipated; however, in the event that a Navy vessel strikes a whale, the Navy shall do the following: PO 00000 Frm 00029 Fmt 4701 Sfmt 4700 46139 Immediately report to NMFS (pursuant to the established Communication Protocol) the: • Species identification (if known); • Location (latitude/longitude) of the animal (or location of the strike if the animal has disappeared); • Whether the animal is alive or dead (or unknown); and • The time of the strike. As soon as feasible, the Navy shall report to or provide to NMFS, the: • Size, length, and description (critical if species is not known) of animal; • An estimate of the injury status (e.g., dead, injured but alive, injured and moving, blood or tissue observed in the water, status unknown, disappeared, etc.); • Description of the behavior of the whale during event, immediately after the strike, and following the strike (until the report is made or the animal is no longer sighted); • Vessel class/type and operational status; • Vessel length; • Vessel speed and heading; and • To the best extent possible, obtain a photo or video of the struck animal, if the animal is still in view. Within 2 weeks of the strike, provide NMFS: • A detailed description of the specific actions of the vessel in the 30minute timeframe immediately preceding the strike, during the event, and immediately after the strike (e.g., the speed and changes in speed, the direction and changes in direction, other maneuvers, sonar use, etc., if not classified); • A narrative description of marine mammal sightings during the event and immediately after, and any information as to sightings prior to the strike, if available; and use established Navy shipboard procedures to make a camera available to attempt to capture photographs following a ship strike. NMFS and the Navy will coordinate to determine the services the Navy may provide to assist NMFS with the investigation of the strike. The response and support activities to be provided by the Navy are dependent on resource availability, must be consistent with military security, and must be logistically feasible without compromising Navy personnel safety. Assistance requested and provided may vary based on distance of strike from shore, the nature of the vessel that hit the whale, available nearby Navy resources, operational and installation commitments, or other factors. E:\FR\FM\03AUR2.SGM 03AUR2 46140 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations Annual Monitoring Reports As noted above, reports from individual monitoring events, results of analyses, publications, and periodic progress reports for specific monitoring projects would be posted to the Navy’s Marine Species Monitoring web portal and NMFS’ Web site as they become available. Progress and results from all monitoring activity conducted within the MITT Study Area, as well as required Major Training Exercise activity, would be summarized in an annual report. A draft report would be submitted either 90 days after the calendar year or 90 days after the conclusion of the monitoring year, date to be determined by the adaptive management review process. In the past, each annual report has summarized data for a single year. At the Navy’s suggestion, future annual reports would take a cumulative approach in that each report will compare data from that year to all previous years. For example, the third annual report will include data from the third year and compare it to data from the first and second years. This will provide an ongoing cumulative look at the Navy’s annual monitoring and exercise and testing reports and eliminate the need for a separate comprehensive monitoring and exercise summary report at the end of the 5-year period. Annual Exercise and Testing Reports The Navy shall submit preliminary reports detailing the status of authorized sound sources within 21 days after the anniversary of the date of issuance of the LOA. The Navy shall submit detailed reports 3 months after the anniversary of the date of issuance of the LOA. The detailed annual reports shall contain information on Major Training Exercises (MTE), Sinking Exercise (SINKEX) events, and a summary of sound sources used, as described below. The analysis in the detailed reports will be based on the accumulation of data from the current year’s report and data collected from previous reports. mstockstill on DSK4VPTVN1PROD with RULES2 Comments and Responses On March 19, 2014 (79 FR 15388), NMFS published a proposed rule in response to the Navy’s request to take marine mammals incidental to training and testing activities in the MITT Study Area and requested comments, information, and suggestions concerning the request. During the 45-day public comment period, NMFS received comments from the Marine Mammal Commission, private citizens, and an elected official (Senator Vicente (ben) C. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Pangelinan, 32nd Guam legislature). Comments specific to section 101(a)(5)(A) of the MMPA and NMFS’ analysis of impacts to marine mammals are summarized, sorted into general topic areas, and addressed below and/or throughout the final rule. Comments specific to the MITT EIS/OEIS, which NMFS participated in developing as a cooperating agency and adopted, or that were also submitted to the Navy during the MITT DEIS/OEIS public comment period are addressed in Appendix E (Public Participation) of the FEIS/OEIS. The Natural Resources Defense Council (NRDC) did not submit comments specific to the proposed MITT rulemaking; however, NRDC has indicated their full endorsement of the comments and management recommendations submitted on the MITT DEIS/OEIS by the Commonwealth of the Northern Mariana Islands (Governor Eloy S. Inos). Those comments are addressed in Appendix E of the FEIS/OEIS and are considered by NMFS and the Navy in the context of both this rulemaking and related NEPA compliance. Comments submitted by Governor Inos that are most applicable to this rulemaking include recommended mitigation areas and are addressed below. Last, some commenters presented technical comments on the general behavioral risk function that are largely identical to those posed during the comment period for proposed rules for the Hawaii Range Complex (HRC), Atlantic Fleet Active Sonar Training (AFAST), Atlantic Fleet Training and Testing (AFTT), and Hawaii-Southern California Training and Testing (HSTT) study areas, predecessors to the MITT rule. The behavioral risk function remains unchanged since then, and here we incorporate our responses to those initial technical comments (74 FR 1455, Acoustic Threshold for Behavioral Harassment section, page 1473; 74 FR 4844, Behavioral Harassment Threshold section, page 4865; 78 FR 73010, Acoustic Thresholds section, page 73038; 78 FR 78106, Acoustic Thresholds section, page 78129). Full copies of the comment letters may be accessed at https://www.regulations.gov. Marine Mammal Density Estimates Comment 1: The Commission recommended that NMFS require the Navy to (1) account for uncertainty in extrapolated density estimates for all species by using the upper limit of the 95% confidence interval or the arithmetic mean plus two standard deviations and (2) then re-estimate the numbers of takes accordingly. PO 00000 Frm 00030 Fmt 4701 Sfmt 4700 Response 1: The Navy coordinated with both NMFS’ Pacific Islands Fisheries Science Center (PIFSC) and Southwest Fisheries Science Center (SWFSC) to identify the best available density estimates for marine mammals occurring in the Study Area. In all cases, a conservative (i.e., greater) estimate was selected. The Navy’s use of a mean density estimate is consistent with the approach taken by NMFS to estimate and report the populations of marine mammals in their Stock Assessment Reports and the estimated mean is thus considered the ‘‘best available data.’’ Adjusting the mean estimates as suggested would result in unreasonable measures, particularly given the very high coefficient of variation (CV) associated with most marine mammal density estimates. Further, the Navy’s acoustic model includes conservative estimates of all parameters (e.g., assumes that the animals do not move horizontally, assumes animals are always head-on to the sound source so that they receive the maximum amount of energy, etc.) resulting in a more conservative (i.e., greater) assessment of potential impacts. Mitigation, Monitoring, and Reporting Comment 2: Governor Eloy S. Inos (Commonwealth of the Northern Mariana Islands [CNMI]) recommended (via comments submitted on the MITT DEIS/OEIS) specific geographic marine mammal mitigation areas—or habitat protection areas—to be avoided by all Navy sonar and explosives training and testing activities. These include nearisland habitat in the vicinity of the islands of the CNMI, landward of the 3,500 m isobath (based on concentrations of insular populations of odontocetes within the 3,500 m isobath around the Hawaiian Islands); and from the West Mariana Ridge (a chain of conical seamounts paralleling 145 to 170 km west of the Mariana Islands) to the 3,500 m isobaths around the ridge, between roughly 13° and 18° N where two beaked whale sightings were made during a Navy line-transect survey in 2007, passive acoustic data acquired during that same survey showed multiple detections of short-finned pilot whales around the ridgeline, and satellite tagging efforts showed use of the ridge by at least one false killer whale tagged off Rota (Hill et al., 2013). Response 2: Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the ‘‘means of effecting the least practical adverse impact on such species or stock and its habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance.’’ The NDAA amended the E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations MMPA as it relates to military-readiness activities (which these Navy activities are) and the incidental take authorization process such that ‘‘least practicable adverse impact’’ shall include consideration of personnel safety, practicality of implementation, and impact on the effectiveness of the ‘‘military readiness activity.’’ Therefore, as discussed earlier in the Mitigation section, in making a determination of ‘‘least practicable adverse impact,’’ NMFS considers the likely benefits of a mitigation measures being considered to affected species or stocks and their habitat, as well as the likely effect of those measures on personnel safety, practicality of implementation, and the impact on the effectiveness of the military readiness activity. With respect to the effectiveness of area limitations, temporal (e.g., seasonal) or geographic limitations (time/area limitations) are a direct and effective means of reducing adverse impacts to marine mammals. By reducing the overlap in time and space of the known concentrations of marine mammals and the acoustic footprint associated with the thresholds for the different types of take (either at all times and places where animals are concentrated, or times and places where they are concentrated for specifically important behaviors (such as reproduction or feeding)), the amount of take can be reduced. It is most effective when these measures are used carefully at times and places where their effects are relatively well known. For example, if there is credible evidence that concentrations of marine mammals are known to be high at a specific place or during a specific time of the year (such as the high densities of humpback whales delineated on the Mobley map in the HRC, or North Atlantic right whale critical habitat on the east coast), then these seasonal or geographic exclusions or limitations may be appropriate. However, if marine mammals are known to prefer certain types of areas (as opposed to specific areas) for certain functions, such as beaked whale use of seamounts or marine mammal use of productive areas like cyclonic eddies, which means that they may or may not be present at any specific time, it is less effective to require avoidance or limited use of the area because they may not be present. The Governor’s recommendation that the Navy exclude sonar and explosives training and testing in the vicinity of the islands of the CNMI landward of the 3,500 m isobaths is based on the fact that in Hawaii insular populations of odontocetes are generally concentrated on important near-island habitat within VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 the 3,500 m isobaths. However, there is nothing to suggest that a similar isobath represents the delineation of important near-island habitat for concentrations of marine mammals around the islands of the CNMI. In fact, satellite tag deployment data from cetacean (shortfinned pilot whales, false killer whales, rough-toothed dolphins, bottlenose dolphins, and melon-headed whales) surveys in the waters surrounding Guam and the CNMI during 2010–2014, conducted by the Pacific Islands Fisheries Science Center (PIFSC) in partnership with the Navy, showed that multiple tagged species utilized the areas far offshore beyond the 3,500 m isobath (Hill et al., 2014). These findings are corroborated by line transect surveys conducted by Fulling et al. (2011), which document multiple encounters and wide distribution of bottlenose dolphins, rough-toothed dolphins, pantropical spotted dolphins, false killer whales, and sperm whales far offshore of Guam and the CNMI at depths up to 9,874 m. NMFS, therefore, does not consider the near-island waters landward of the 3,500 m isobaths around the islands of the CNMI an appropriate time/area limitation for training and testing activities in the Study Area. Regarding the Governor’s recommendation that the Navy not conduct sonar and explosives training and testing from the West Mariana Ridge to the 3,500 m isobath around the ridge, the relatively limited data cited by the Governor is not suggestive of high concentrations of marine mammals or marine mammal species (i.e., two beaked whales, three short-finned pilot whales, one false killer whale) specific to this ridge. In fact, satellite tagging efforts by PIFSC indicated the vast majority of tagged false killer whales occurred well beyond, and east of, the West Mariana Ridge ridgeline (Hill et al., 2014 and 2015). And while the Navy’s line-transect survey and passive acoustic monitoring conducted in 2007 noted the presence of a few individuals of short-finned pilot whales (and beaked whales) along portions of the West Mariana Ridge, PIFSC telemetry data analyzed by Hill et al. (2015) indicate a preference away from the ridge and closer to the near-island waters around Guam (though not exclusively so). NMFS recognizes the generally biologically productive nature of some ridges and seamounts; however, there are no data to suggest that important or species-specific habitat (rookeries, reproductive, feeding) exists along the West Mariana Ridge or within the 3,500 m isobath around the ridge. PO 00000 Frm 00031 Fmt 4701 Sfmt 4700 46141 In addition to NMFS’ consideration of the effectiveness of the time/area restrictions recommended by Governor Eloy S. Inos, the Navy has provided in the MITT FEIS/OEIS the following specific reasons explaining why these types of geographic restrictions or limitations are considered impracticable for the Navy: • Broad Coastal Restrictions (e.g., around entire islands) Based on Distances from Isobaths or Shorelines— Avoiding locations for training and testing activities within the Study Area based on wide-scale distances from isobaths or the shoreline for the purpose of mitigation would be impractical with regard to implementation of military readiness activities, result in unacceptable impact on readiness, and would not be an effective means of mitigation, and would increase safety risks to personnel. Training in shallower water is an essential component to maintaining military readiness. Sound propagates differently in shallower water and operators must learn to train in this environment. Additionally, submarines have become quieter through the use of improved technology and have learned to hide in the higher ambient noise levels of the shallow waters of coastal environments. In real world events, it is highly likely Sailors would be working in, and therefore must train in, these types of areas. The littoral waterspace is also the most challenging area to operate in due to a diverse acoustic environment. It is not realistic or practicable to refrain from training in the areas that are the most challenging and operationally important. Operating in shallow water is essential in order to provide realistic training on real world combat conditions with regard to shallow water sound propagation. • Avoiding Locations Based on Bathymetry—Requiring training and testing to avoid large areas that encompass a large portion of a particular bathymetric conditions (e.g., high-relief seamounts such as those that comprise the West Mariana Ridge) within a designated Range Complex or study area for the purpose of mitigation would increase safety risks to personnel and result in unacceptable impact on readiness. Limiting training and testing (including the use of sonar and other active acoustic sources or explosives) to avoid steep or complex bathymetric features (e.g., seamounts) would reduce the realism of the military readiness activity. Systems must be tested in a variety of bathymetric conditions to ensure functionality and accuracy in a variety of environments. Sonar operators need to train as they would E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46142 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations operate during real world combat situations. Because real world combat situations include diverse bathymetric conditions, Sailors must be trained to handle bottom bounce, sound passing through changing currents, eddies, or across changes in ocean temperature, pressure, or salinity. Training with reduced realism would alter Sailors’ abilities to effectively operate in a real world combat situation, thereby resulting in an unacceptable increased risk to personnel safety and the sonar operator’s ability to achieve mission success. A more detailed discussion can be found in Section 5.3.4.1 of the MITT FEIS/OEIS. In conclusion, NMFS has considered the time/area restrictions recommended by Governor Eloy S. Inos and has determined that requiring those measures would not reduce adverse effects to marine mammal populations or stocks or provide additional protection of marine mammal populations or stocks in the Study Area beyond those mitigation measures already proposed in the MITT EIS/OEIS and in this final rule (see Mitigation section above). Further, NMFS has considered the Navy’s conclusion that such limitations would impose an increased safety risk to personnel, an unacceptable impact on the effectiveness of training and testing activities that would affect military readiness, and an impractical burden with regard to implementation (This process is further detailed in Section 5.2.3 of the MITT FEIS/OEIS). Comment 3: Senator Vicente (ben) C. Pangelinan (32nd Guam Legislature) expressed concerns with the effectiveness of the mitigation measures (e.g., Lookouts) outlined in the proposed rule. The Senator also questioned whether or not animals exposed to Navy sound sources will return to their usual locations. Response 3: NMFS has carefully evaluated the Navy’s proposed suite of mitigation measures and considered a broad range of other measures (including those recommended during the proposed rule public comment period) in the context of ensuring that NMFS prescribes the means of effecting the least practicable adverse impact on the affected marine mammal species and stocks and their habitat. Based on our evaluation of the Navy’s proposed measures, as well as other measures considered by NMFS or recommended by the public, NMFS has determined that the Navy’s proposed mitigation measures (especially when the adaptive management component is taken into consideration (see Adaptive VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Management, below)), along with the additions detailed in the Mitigation section above, are adequate means of effecting the least practicable adverse impacts on marine mammals species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, while also considering personnel safety, practicality of implementation, and impact on the effectiveness of the military readiness activity. Regarding Navy Lookouts, Lookouts are a vital aspect of the strategy for limiting potential impacts from Navy activities. Lookouts are qualified and experienced observers of the marine environment. All Lookouts take part in Marine Species Awareness Training so that they are better prepared to spot marine mammals. Detailed information on the Navy’s Marine Species Awareness Training program, which speaks to qualifications and training, is also provided in Chapter 5 of the MITT FEIS/OEIS. Their primary duty is to detect objects in the water, estimate the distance from the ship, and identify them as any number of inanimate or animate objects that are significant to a Navy activity or as a marine mammal so that the mitigation measure can be implemented. Lookouts are on duty at all times, day and night, when a ship or surfaced submarine is moving through the water. Lookouts are used continuously, throughout the duration of activities that involve the following: Active sonar, Improved Extended Echo Ranging (IEER) sonobuoys, antiswimmer grenades, positive control firing devices, timedelay firing devices, gunnery exercises (surface target), missile exercises (surface target), bombing exercises, torpedo (explosive) testing, sinking exercises, at-sea explosives testing, vessels underway, towed in-water devices (from manned platforms), and non-explosive practice munitions. Visual detections of marine mammals would be communicated immediately to a watch station for information disseminations and appropriate mitigation action. The Navy will use passive acoustic monitoring to supplement visual observations by Lookouts during IEER sonobuoy activities, explosive sonobuoys using 0.6–2.5 pound (lb) net explosive weight, torpedo (explosive) testing, and sinking exercises, to detect marine mammal vocalizations. Passive acoustic detections will be reported to Lookouts to increase vigilance of the visual observation. NMFS has carefully considered Navy’s use of Lookouts and determined that in combination with PO 00000 Frm 00032 Fmt 4701 Sfmt 4700 the Stranding Response Plans, and the other mitigation measures identified, the Navy’s mitigation plan will effect the least practicable adverse impacts on marine mammal species or stocks and their habitat. There are numerous studies which document the return of marine mammals (both odontocetes and mysticetes) following displacement of an individual (i.e., short-term avoidance) from an area as a result of the presence of a sound (Bowles et al., 1994; Goold, 1996; 1998; Stone et al., 2000; Morton and Symonds, 2002; Gailey et al., 2007; Claridge and Durban 2009; Moretti et al., 2009; McCarthy et al., 2011; Tyack et al., 2011). These studies are referenced and discussed in both the Navy’s LOA application (Chapter 6) and the proposed rule (79 FR 15403, March 19, 2014), as well as in the Analysis and Negligible Impact Determination section of this final rule. Comment 4: Senator Vicente (ben) C. Pangelinan (32nd Guam Legislature) expressed concerns with the Navy’s inability to mitigate for onset of TTS during every activity. Other commenters (e.g., Governor Eloy S. Inos, CNMI) on the MITT DEIS/OEIS expressed similar concerns regarding the size of recommended mitigation zones, particularly those proposed for MF1 sonar system activities in which the Governor recommended the Navy ‘‘establish a wider buffer, to the maximum extent practicable.’’ Response 4: As discussed in the proposed rule (79 FR 15388, March 19, 2014), TTS is a type of Level B harassment. In the Estimated Take of Marine Mammal section, we quantify the effects that might occur from the specific training and testing activities that the Navy proposes in the MITT Study Area, which includes the number of takes by Level B harassment (behavioral harassment, acoustic masking and communication impairment, and TTS). Through this rulemaking, NMFS has authorized the Navy to take marine mammals by Level B harassment incidental to Navy training and testing activities in the MITT Study Area. In order to issue an ITA, we must set forth the ‘‘permissible methods of taking pursuant to such activity, and other means of effecting the least practical adverse impact on such species or stock and its habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance.’’ We have determined that the mitigation measures implemented under this rule effect the least practical adverse impact on marine mammal species and stocks and their habitat. E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations The Navy developed activity-specific mitigation zones based on the Navy’s acoustic propagation model. Each recommended mitigation zone is intended to avoid or reduce the potential for onset of the lowest level of injury, PTS, out to the predicted maximum range. Mitigating to the predicted maximum range to PTS consequently also mitigates to the predicted maximum range to onset mortality (1 percent mortality), onset slight lung injury, and onset slight gastrointestinal tract injury, since the maximum range to effects for these criteria are shorter than for PTS. Furthermore, in most cases, the mitigation zone actually covers the TTS zone. In some instances, the Navy recommended mitigation zones are larger or smaller than the predicted maximum range to PTS based on the associated effectiveness and operational assessments presented in Section 5.2.3 of the MITT FEIS/OEIS. NMFS worked closely with the Navy in the development of the recommendations and carefully considered them prior to adopting them in this final rule. The mitigation zones contained in this final rule represent the maximum area the Navy can effectively observe based on the platform of observation, number of personnel that will be involved, and the number and type of assets and resources available. As mitigation zone sizes increase, the potential for reducing impacts decreases. For instance, if a mitigation zone increases from 1,000 to 4,000 yd. (914 to 3,658 m), the area that must be observed increases sixteen-fold, which is not practicable. The mitigation measures contained in this final rule balance the need to reduce potential impacts with the Navy’s ability to provide effective observations throughout a given mitigation zone. Implementation of mitigation zones is most effective when the zone is appropriately sized to be realistically observed. The Navy does not have the resources to maintain additional Lookouts or observer platforms that would be needed to effectively observe mitigation zones of increased size. Comment 5: The Commission recommended that NMFS require the Navy to provide the predicted average and maximum ranges for all impact criteria (i.e., behavioral response, TTS, PTS, onset slight lung injury, onset slight gastrointestinal injury, and onset mortality), for all activities (i.e., based on the activity category and representative source bins and include ranges for more than 1 ping), and for all functional hearing groups of marine mammals within MITT representative VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 environments (including shallow-water nearshore areas). Response 5: The Navy discusses range to effects in Sections 3.4.4.1.1 and 3.4.4.2.1 of the MITT FEIS/OEIS. The active acoustic tables in Section 3.4.4.1.1 illustrate the ranges to PTS, TTS, and behavioral response. The active acoustic tables for PTS and TTS show ranges for all functional hearing groups and the tables for behavioral response show ranges for low-, mid-, and high-frequency cetaceans. The active acoustic source class bins used to assess range to effects represent some of the most powerful sonar sources and are often the dominant source in an activity. The explosives table in Section 3.4.4.2.1 illustrates the range to effects for onset mortality, onset slight lung injury, onset slight gastrointestinal tract injury, PTS, TTS, and behavioral response. The explosives table shows ranges for all functional hearing groups. The source class bins used for explosives range from the smallest to largest amount of net explosive weight. These ranges represent conservative estimates (i.e., longer ranges) based on the assumption that all impulses are 1-second in duration. In fact, most impulses are much shorter and contain less energy. Therefore, these ranges provide realistic maximum distances over which the specific effects would be possible. NMFS believes that these representative sources provide adequate information to analyze potential effects on marine mammals. Because the Navy conducts training and testing in a variety of environments having variable acoustic propagation conditions, variations in acoustic propagation conditions are considered in the Navy’s acoustic modeling and the quantitative analysis of acoustic impacts. Average ranges to effect are provided in the MITT FEIS/OEIS to show the reader typical zones of impact around representative sources. As noted in the LOA application and MITT FEIS/OEIS, the ranges provided in the analysis sections (Section 6 of the LOA and Chapter 3 of the MITT FEIS/OEIS) are the average range to all effects for representative sources in a variety of environments (shallow and deep water). These are not nominal values for deepwater environments, as repeatedly asserted by the Commission. Comment 6: The Commission recommended that NMFS require the Navy to use passive and active acoustics to supplement visual monitoring during implementation of mitigation measures for all activities that could cause Level A harassment or mortality beyond those explosive activities for which passive acoustic monitoring was already PO 00000 Frm 00033 Fmt 4701 Sfmt 4700 46143 proposed. Specifically, the Commission questioned why passive and active acoustic monitoring used during the Navy’s Surveillance Towed Array Sensory System Low Frequency Active (SURTASS LFA) activities is not applied here. Response 6: The Navy requested Level A (injury) take of marine mammals for impulse and non-impulse sources during training and testing based on its acoustic analysis. While it is impractical for the Navy to conduct passive acoustic monitoring during all training and testing activities (due to lack of resources), the Navy has engineered the use of passive acoustic detection for monitoring purposes, taking into consideration where the largest impacts could potentially occur, and the effectiveness and practicability of installing or using these devices. The Navy will use passive acoustic monitoring to supplement visual observations during Improved Extended Echo Ranging (IEER) sonobuoy activities, explosive sonobuoys using 0.6–2.5 pound (lb) net explosive weight, torpedo (explosive) testing, and sinking exercises, to detect marine mammal vocalizations. However, it is important to note that passive acoustic detections do not provide range or bearing to detected animals, and therefore cannot provide locations of these animals. Passive acoustic detections will be reported to lookouts to increase vigilance of the visual observation. The active sonar system used by SURTASS LFA is unique to the platforms that use SURTASS LFA. Moreover, this system requires the platforms that carry SURTASS LFA to travel at very slow speeds for the system to be effective. For both of these reasons it is not possible for the Navy to use this system for the platforms analyzed in the MITT FEIS/OEIS. NMFS believes that the Navy’s suite of mitigation measures (which include mitigation zones that exceed or meet the predicted maximum distance to PTS) will typically ensure that animals will not be exposed to injurious levels of sound. To date, the monitoring reports submitted by the Navy for MIRC (or the AFTT and HSTT Study Areas), do not show any evidence of injured marine mammals. Comment 7: The Commission recommended that NMFS require the Navy to use a second clearance category of 60 minutes for deep-diving species (i.e., beaked whales and sperm whales) if the animal has not been observed exiting the mitigation zone following shutdown of acoustic activities due to a marine mammal sighting. E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46144 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations Response 7: NMFS does not concur with the Commission’s recommendation that the Navy should use a second clearance category of 60 minutes for deep-diving species for the following reasons: • As described in the MITT FEIS/ OEIS in Chapter 5 (Standard Operating Procedures, Mitigation, and Monitoring), a 30-minute wait period more than covers the average dive times of most marine mammals. • The ability of an animal to dive longer than 30 minutes does not mean that it will always do so. Therefore, the 60-minute delay would only potentially add value in instances when animals had remained under water for more than 30 minutes. • Navy vessels typically move at 10– 12 knots (5–6 m/sec) when operating active sonar and potentially much faster when not. Fish et al. (2006) measured speeds of seven species of odontocetes and found that they ranged from 1.4– 7.30 m/sec. Even if a vessel was moving at the slower typical speed associated with active sonar use, an animal would need to be swimming near sustained maximum speed for an hour in the direction of the vessel’s course to stay within the safety zone of the vessel. Increasing the typical speed associated with active sonar use would further narrow the circumstances in which the 60-minute delay would add value. • Additionally, the times when marine mammals are deep-diving (i.e., the times when they are under the water for longer periods of time) are the same times that a large portion of their motion is in the vertical direction, which means that they are far less likely to keep pace with a horizontally moving vessel. • Given that, the animal would need to have stayed in the immediate vicinity of the sound source for an hour, and considering the maximum area that both the vessel and the animal could cover in an hour, it is improbable that this would randomly occur. Moreover, considering that many animals have been shown to avoid both acoustic sources and ships without acoustic sources, it is improbable that a deep-diving cetacean (as opposed to a dolphin that might bow ride) would choose to remain in the immediate vicinity of the source. In summary, NMFS believes that it is unlikely that a single cetacean would remain in the safety zone of a Navy sound source for more than 30 minutes, and therefore disagrees with the Commission that a second clearance category of 60 minutes for deep-diving species is necessary. Comment 8: The Commission recommended that NMFS require the Navy to (1) provide the range to effects VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 for all impact criteria (i.e., behavioral response, TTS, PTS, onset slight lung injury, onset slight gastrointestinal injury, and onset mortality) for underwater detonations that involve time-delay firing devices based on sound propagation in shallow-water nearshore environments for the associated marine mammal functional hearing groups and (2) use those data coupled with the maximum charge weight and average swim speed of the fastest group of marine mammals as the basis for the mitigation zone for underwater detonations that involve time-delay firing devices. If NMFS does not require the Navy to adjust its mitigation zones, then it should authorize the numbers of takes for Level A harassment and mortality based on the possibility that marine mammals could be present in the mitigation zone when the explosives detonate and based on updated, more realistic swim speeds. Response 8: As shown in the LOA application (Table 11–1) and MITT FEIS/OEIS (Table 5.3–2), which provide ranges to effects for explosive sources used in the MITT Study Area, the maximum range to PTS effects for a 20 lb. NEW charge used with this activity is 102 yd. (93 m), and the average range to TTS effects is 407 yd. (372 m). A 20 lb. NEW charge is the largest used in Mine Neutralization Activities Using Diver-Placed Time-Delay Firing Devices. These ranges to effects for explosive sources represent conservative estimates assuming all impulses (i.e., explosions) are 1 second in duration. In fact, most impulses from explosions are much less than 1 second in duration and therefore contain much less energy than the amount of energy used to produce the estimated ranges to effects. The proposed mitigation zone of 1,000 yd. (914 m) is well beyond the estimated range to effects and is overprotective for mine neutralization activities using diver-placed time-delay firing devices. The ranges to onset mortality, onset slight lung injury, and onset gastrointestinal injury are all less than the range to PTS level effects and would be well within the mitigation zone. As described in Chapter 5, Section 5.3.1.2.2.5 (Mine Neutralization Activities Using Diver-Placed TimeDelay Firing Devices) of the MITT FEIS/ OEIS, four Lookouts and two small boats represent the maximum level of effort that the Navy can commit for observing the mitigation zone for this activity given the number of personnel and assets available. In addition to the four lookouts, divers and aircrew (if aircraft are involved in the activity) would also serve as lookouts in addition to conducting their regular duties to PO 00000 Frm 00034 Fmt 4701 Sfmt 4700 support the activity. As noted by Navy in previous responses to comments on other Navy training and testing EIS/ OEISs, the mitigation zone is sufficiently large to account for a portion of the distance that a marine mammal could potentially travel during the time delay based on a reasonable assumption of marine mammal swim speeds. The supplemental information presented by the Commission to support the comment points out that Table 6–12 in the LOA application does not present ranges to effects for Bin E6 (up to a 20 lb. NEW). As stated in the table heading, the table is intended to be representative and is not specific to the MITT Study Area; therefore not all bins are included. However, the table shows that the proposed mitigation zone of 1,000 yd. (914 m) would also be protective against injury exposures from explosives in Bin E7 (21 lb. to 60 lb. NEW). Furthermore, as a result of essential fish habitat consultations with NMFS, the Navy has agreed to maintain the maximum NEW charge used at the Outer Apra Harbor Underwater Detonation Site at 10 lb. NEW and not to increase the maximum NEW to 20 lb., as proposed under Alternatives 1 and 2 of the FEIS/OEIS and in the Navy’s LOA application. A maximum charge of 20 lb. NEW is still proposed for use at the Agat Bay Mine Neutralization Site, which is farther from shore and in deeper water. The maximum charge at the Piti Floating Mine Neutralization Site will also remain at 10 lb. NEW. Comment 9: The Commission recommended that NMFS require the Navy to submit a proposed monitoring plan for the MITT Study Area for public review and comment prior to issuance of final regulations. Response 9: NMFS provided an overview of the Navy’s Integrated Comprehensive Monitoring Program (ICMP) in the proposed rule (79 FR 15388, March 19, 2014). While the ICMP does not specify actual monitoring field work or projects, it does establish top level goals that have been developed by the Navy and NMFS. As explained in the proposed rule, detailed and specific studies will be developed as the ICMP is implemented and funding is allocated. Since the proposed rule was published, the Navy has provided a more detailed short-term plan for the first year of the rule. Monitoring in 2015 will be a combination of previously funded FY–14 ‘‘carry-over’’ projects from Phase I and new FY–15 project starts under the vision for Phase II monitoring. A more detailed description of the Navy’s planned projects starting E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations in 2015 (and some continuing from previous years) are available on NMFS’ Web site (www.nmfs.noaa.gov/pr/ permits/incidental/). Additionally, NMFS will provide one public comment period on the Navy’s monitoring program during the 5-year regulations. At this time, the public will have an opportunity (likely in the second year) to comment specifically on the Navy’s MITT monitoring projects and data collection to date, as well as planned projects for the remainder of the regulations. The public also has the opportunity to review the Navy’s monitoring reports, which are posted and available for download every year from the Navy’s marine species monitoring Web site: https:// www.navymarinespeciesmonitoring.us/. Details of already funded MITT monitoring projects and new start projects are available through the Navy’s marine species monitoring Web site: https:// www.navymarinespeciesmonitoring.us/. The Navy will update the status of their monitoring projects through the marine species monitoring site, which serves as a public portal for information regarding all aspects of the Navy’s monitoring program, including background and guidance documents, access to reports, and specific information on current monitoring projects. Through the adaptive management process (including annual meetings), the Navy will coordinate with NMFS and the Commission to review and revise, if required, the list of intermediate scientific objectives that are used to guide development of individual monitoring projects. As described previously in the Monitoring section of this document, NMFS and the Commission will also have the opportunity to attend annual monitoring program science review meetings and/or regional Scientific Advisory Group meetings. The Navy will continue to submit annual monitoring reports to NMFS, which describe the results of the adaptive management process and summarize the Navy’s anticipated monitoring projects for the next reporting year. NMFS will have a threemonth review period to comment on the next year’s planned projects, ongoing regional projects, and proposed new project starts. NMFS’ comments will be submitted to the Navy prior to the annual adaptive management meeting to facilitate a meaningful and productive discussion between NMFS, the Navy, and the Commission. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Effects Analysis/Takes Comment 10: The Commission recommended that NMFS authorize the total numbers of model-estimated Level A harassment and mortality takes rather than allowing the Navy to reduce the estimated numbers of Level A harassment and mortality takes based on the Navy’s proposed post-model analysis. Response 10: NMFS believes that the post-modeling analysis is an effective method for quantifying the implementation of mitigation measures to reduce impacts on marine mammals, and that the resulting exposure estimates are, nevertheless, a conservative estimate of impacts on marine mammals. See Section 3.4.3.2 (Marine Mammal Avoidance of Sound Exposures) as presented in the MITT FEIS/OEIS for the discussion of the science regarding the avoidance of sound sources by marine mammals. In addition, the Technical Report, Post-Model Quantitative Analysis of Animal Avoidance Behavior and Mitigation Effectiveness for the Mariana Islands Training and Testing (https://www.mitteis.com), goes into detail on how the avoidance and mitigation factors were used and provides scientific support from peer-reviewed research. The Navy analysis does not indicate nor is it expected that marine mammals would abandon important habitat on a longterm or even permanent basis. As presented in Section 3.4.5.2 (Summary of Observations During Previous Navy Activities) of the MITT FEIS/OEIS, the information gathered to date including research, monitoring before, during, and after training and testing events across the Navy since 2006, has resulted in the assessment that it is unlikely there will be impacts on populations of marine mammals (such as whales, dolphins and porpoise) having any long-term consequences as a result of the proposed continuation of training and testing in the ocean areas historically used by the Navy including the Study Area. As part of the post-modeling analysis, the Navy reduced some predicted PTS exposures and mortality based on the potential for marine mammals to be detected and mitigation implemented. Given this potential, not taking into account some possible reduction in Level A exposures and mortality would result in a less realistic, overestimation of possible Level A and mortality takes, as if there were no mitigation measures implemented. The period of time between clearing the impact area of any non-participants or marine mammals and weapons release is on the order of PO 00000 Frm 00035 Fmt 4701 Sfmt 4700 46145 minutes, making it highly unlikely that a marine mammal would enter the mitigation zone. The assignment of mitigation effectiveness scores and the appropriateness of consideration of sightability using detection probability, g(O), when assessing the mitigation in the quantitative analysis of acoustic impacts is discussed in the MITI FEIS/ OEIS (Section 3.4.3.3, Implementing Mitigation to Reduce Sound Exposures). Additionally, the activity category, mitigation zone size, and number of Lookouts are provided in the proposed rule (FR 79 15388) and MITT FEIS/OEIS (Section 5, Tables 5.3–2 and 5.4–1). In addition to the information already contained within the MITT FEIS/OEIS, the Post-Model Quantitative Analysis of Animal Avoidance Behavior and Mitigation Effectiveness for the Mariana Islands Training and Testing Technical Report (https://www.mitt-eis.com) describes the process for the postmodeling analysis in further detail. There is also information on visual detection leading to the implementation of mitigation in the annual exercise reports provided to NMFS and briefed annually to NMFS and the Commission. These annual exercise reports have been made available and can be found at https:// www.navymarinespeciesmonitoring.us/ in addition to https://www.nmfs.noaa/pr/ permits/incidental. In summary, NMFS and the Navy believe consideration of marine mammal sightability and activityspecific mitigation effectiveness is appropriate in the Navy’s quantitative analysis in order to provide decision makers a reasonable assessment of potential impacts under each alternative. A comprehensive discussion of the Navy’s quantitative analysis of acoustic impacts, including the postmodel analysis to account for mitigation and avoidance, is presented in Chapter 6 of the LOA application. Comment 11: The Commission recommended that NMFS require the Navy to round its takes, based on those takes in the MITT FEIS/OEIS Criteria and Thresholds Technical Report tables, to the nearest whole number or zero in all of its take tables and then authorize those numbers of takes. Response 11: The exposure numbers presented in the MITT FEIS/OEIS Criteria and Thresholds Technical Report are raw model output that have not been adjusted by post-processing to account for likely marine mammal behavior or the effect from implementation of mitigation measures. All fractional post-processed exposures for a species across all events within E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46146 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations each category subtotal (Training, Testing, Impulse, and Non-Impulse) are summed to provide an annual total predicted number of effects. The final exposure numbers presented in the LOA application and the MITT FEIS/OEIS incorporate post-processed exposures numbers that have been rounded down to the nearest integer so that subtotals correctly sum to total annual effects rather than exceed the already overly conservative total exposure numbers. Comment 12: Senator Vicente (ben) C. Pangelinan (32nd Guam Legislature) expressed concerns with the purported lack of data or supporting studies in the proposed rule on how anthropogenic sound will affect reproduction and survival of marine mammals in the Study Area. The Senator cites studies by Claridge (2013) and others (e.g., International Whaling Commission, 2005) that suggest stressors associated with Navy sonar use and impulse sound may lead to strandings and lower reproductive rates in some species. The Senator also points out that several authors have established that long-term and intense disturbance stimuli can cause population declines in some (terrestrial) species. Response 12: NMFS fully considers impacts to recruitment and survival (population-level effects) when making a negligible impact determination and when prescribing the means of effecting the least practicable impact on species and stocks. NMFS is constantly evaluating new science and how to best incorporate it into our decisions. This process involves careful consideration of new data and how it is best interpreted within the context of a given management framework. Recent studies have been published regarding behavioral responses that are relevant to the proposed activities and energy sources: Moore and Barlow, 2013; DeRuiter et al., 2013; and Goldbogen et al., 2013, among others. Each of these articles emphasizes 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. In addition, New et al., 2013 and 2014; Houser et al., 2013; and Claridge, 2013 were recently published. These and other relevant studies are discussed in both the Potential Effects of Specified Activities on Marine Mammals section and the Analysis and Negligible Impact Determination section of this final rule. The Analysis and Negligible Impact Determination section of this final rule includes a species or group-specific analysis (see Group and SpeciesSpecific Analysis) of potential effects on VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 marine mammal in the Study Area, as well as a discussion on long-term consequences (see Long-Term Consequences) for individuals or populations resulting from Navy training and testing activities in the Study Area. As discussed later in this document, populations of beaked whales and other odontocetes in the Bahamas, and in other Navy fixed ranges that have been operating for tens of years, appear to be stable. Range complexes where intensive training and testing have been occurring for decades have populations of multiple species with strong site fidelity (including highly sensitive resident beaked whales at some locations) and increases in the number of some species. There is no direct evidence that routine Navy training and testing spanning decades has negatively impacted marine mammal populations at any Navy range complex. In at least three decades of similar activities, only one instance of injury to marine mammals (March 4, 2011; three longbeaked common dolphin) has been documented as a result of training or testing using an impulse source (underwater explosion). Years of monitoring of Navy-wide activities (since 2006) have documented hundreds of thousands of marine mammals on the range complexes and there are only two instances of overt behavioral change that have been observed. Years of monitoring of Navy-wide activities on the range complexes have documented no demonstrable instances of injury to marine mammals as a direct result of non-impulsive acoustic sources. Stranding events coincident with Navy MFAS use in which exposure to sonar is believed to have been a contributing factor were detailed in the Stranding and Mortality section of the proposed rule. However, for some of these stranding events, a causal relationship between sonar exposure and the stranding could not be clearly established (Cox et al., 2006). In other instances, sonar was considered only one of several factors that, in their aggregate, may have contributed to the stranding event (Freitas, 2004; Cox et al., 2006). NMFS and the Navy have identified certain circumstances/factors (including 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 sonars) that have been present in some instances where strandings are associated with active Navy sonar (e.g., Bahamas, 2000). Based PO 00000 Frm 00036 Fmt 4701 Sfmt 4700 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. In addition, the Navy has developed specific planning and monitoring measures to use when that suite of factors is present. These circumstances/factors do not exist in their aggregate in the MITT Study Area. Because of the association between tactical MFA 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 a suite of mitigation intended to more broadly minimize impacts to marine mammals, the Navy and NMFS have a detailed Stranding Response Plan that outlines reporting, communication, and response protocols intended both to minimize the impacts of, and enhance the analysis of, any potential stranding in areas where the Navy operates. Based on the best available science NMFS concludes that exposures to marine mammal species and stocks due to MITT activities would result in only short-term effects to most individuals exposed and are not expected to affect annual rates of recruitment or survival (population-level impacts having any long-term consequences). Results of the Navy’s acoustic analysis and NMFS’ analysis, as well as the relevant studies supporting this conclusion, are referenced and summarized in the Analysis and Negligible Impact Determination section of this final rule. Criteria and Thresholds Comment 13: The Commission recommended that NMFS require the Navy to (1) use 157 rather than 152 dB re 1 mPa2-sec as the temporary threshold shift (TTS) threshold for high-frequency cetaceans exposed to acoustic sources, (2) use 169 rather than 172 dB re 1 mPa2sec as the TTS thresholds for mid- and low-frequency cetaceans exposed to explosive sources, (3) use 145 rather than 146 dB re 1 mPa2-sec as the TTS threshold for high-frequency cetaceans for explosive sources, and (4)(a) based on these changes to the TTS thresholds, adjust the permanent threshold shift (PTS) thresholds for high-frequency E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations cetaceans exposed to acoustic sources by increasing the amended TTS threshold by 20 dB, and for low-, mid, and high-frequency cetaceans exposed to explosive sources, by increasing the amended TTS thresholds by 15 dB and (b) adjust the behavioral thresholds for low-, mid-, and high-frequency cetaceans exposed to explosive sources by decreasing the amended TTS thresholds by 5 dB. Response 13: NMFS does not concur with the Commissions’ recommendations for similar reasons to those provided in prior responses to Comission comments on the HSTT and AFTT proposed rulemakings. The values derived for impulsive and nonimpulsive TTS are based on data from peer-reviewed scientific studies. The development of these thresholds and criteria is detailed in the Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis Technical Report (Finneran and Jenkins, 2012) that is referenced in the MITT FEIS/OEIS (see Section 3.4.3.1.4 [Thresholds and Criteria for Predicting Acoustic and Explosive Impacts on marine mammals]) and available at https:// www.mitt-eis.com. As presented in Finneran and Jenkins (2012) the thresholds incorporate new findings since the publication of Southall et al. (2007) and the evolution of scientific understanding since that time. Note that Dr. Finneran was one of the authors for Southall et al. (2007) and so is completely familiar with the older conclusions presented in the 2007 publication and, therefore, was able to integrate knowledge into development of the refined approach presented in Finneran and Jenkins (2012) based on evolving science since 2007. Briefly, the original experimental data is weighted using the prescribed weighting function to determine the numerical threshold value. The Commission did not consider the appropriate weighting schemes when comparing thresholds presented in Southall et al. (2007) and those presented in Finneran and Jenkins (2012). TTS thresholds presented in Finneran and Jenkins (2012) are appropriate when the applicable weighting function (Type II) is applied to the original TTS data; TTS thresholds in Southall et al. (2007) were based on M-weighting. For example, while it is true that there is an unweighted 12-dB difference for onset-TTS between beluga watergun (Finneran et al., 2002) and tonal exposures (Schlundt et al., 2000), the difference after weighting with the Type II MF-cet weighting function (from Finneran and Jenkins, 2012), is 6-dB. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 The Commission has confused (a) the 6 dB difference in PTS and TTS thresholds based on peak pressure described in Southall et al. 2007 with (b) the difference between impulsive and non-impulsive thresholds in Finneran and Jenkins (2012), which is coincidentally 6 dB. The same offset between impulsive and non-impulsive temporary threshold shift, for the only species where both types of sound were tested (beluga), was used to convert the Kastak et al. (2005) data (which used non-impulsive tones) to an impulsive threshold. This method is explained in Finneran and Jenkins (2012) and Southall et al. (2007). The thresholds and criteria used in the MITT analysis have already incorporated the correct balance of conservative assumptions that tend towards overestimation in the face of uncertainty. Additional details regarding the process are provided in Section 3.4.3.1.5 (Quantitative Analysis) of the MITT FEIS/OEIS. In addition, the summary of the thresholds used in the analysis are presented in Section 3.4.3.1.4 (Thresholds and Criteria for Predicting Acoustic and Explosive Impacts on Marine Mammals) of the MITT FEIS/OEIS. NMFS was included in the development of the current thresholds. The thresholds used in the current analysis remain the best available estimate of the number and type of take that may result from the Navy’s use of acoustic sources in the MITT Study Area, although NMFS and the Navy will continue to revise those thresholds based on emergent research. Comment 14: The Commission recommended that NMFS require the Navy to (1) describe what it used as the upper limit of behavioral response function for low-frequency cetaceans (BRF1) and the upper limits of BRF2 for both mid- and high-frequency cetaceans, including if it assumed a 1-sec ping for all sources and (2) if the upper limits of the BRFs were based on weighted thresholds, use the unweighted or Mweighted thresholds of 195 dB re 1 mPa2-sec for low- and mid-frequency cetaceans and 176 dB re 1 mPa2-sec for high-frequency cetaceans to revise its behavior take estimates for all marine mammals exposed to acoustic sources. Response 14: The behavioral response functions (BRFs) used to define criteria for assessing behavioral responses to underwater sound sources are discussed in Section 3.4.3.1.4 (Thresholds and Criteria for Predicting Acoustic and Explosive Impacts on Marine Mammals) of the FEIS/OEIS and in the Technical Report, Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Finneran and Jenkins, 2012). PO 00000 Frm 00037 Fmt 4701 Sfmt 4700 46147 The BRFs have been used by the Navy to assess behavioral reactions in marine mammals for several years and are described in greater detail in the Atlantic Fleet Active Sonar Training EIS/OEIS (see Section 4.4.5.3.2 Development of the Risk Function), as well as in the Southern California Range Complex EIS/OEIS and the Hawaii Range Complex EIS/OEIS. Harassment under the BRF and harassment under the TTS criteria are both considered Level B takes under MMPA, and NMFS has determined that animals whose exposure both exceeds TTS threshold and results in behavioral response under the BRF should not be double counted or counted as taken twice by the same acoustic exposure. Although behavioral responses (nonTTS) and TTS are both considered as Level B under the MMPA for military readiness, they are two separate criteria based on different metrics and different frequency weighting systems. Sound exposure level (SEL) is the most appropriate metric to predict TTS, because it accounts for signal duration. Sound pressure level (SPL) is independent of signal duration and is the metric that best correlates with potential behavioral response. Furthermore, to predict TTS, SEL is weighted with a Type II function for cetaceans, whereas to predict a behavioral response, SPL is weighted with a Type I function. Mathematically, SEL (for TTS) and SPL (for behavior) are not on the same linear scale, and their relationship to one another changes based on the frequency and duration of the sounds being analyzed. Based on the model-estimated exposure results, an animat (virtual representation of an animal) exposed to sound that exceeds both the TTS (SEL) threshold and Behavioral (SPL) threshold is reported as a TTS (higher level) effect. It is important to note that TTS is a step function, so 100 percent of animals predicted to equal or surpass the TTS threshold would be counted as TTS effects. Behavioral effects are estimated as the percentage of animals (i.e. between 0 and 100 percent) that may be affected based on the highest received SPL on a BRF. Vessel Strikes Comment 15: The Commission recommended that NMFS require the Navy to use its spatially and temporally dynamic simulation models rather than simple probability calculations to estimate strike probabilities for specific activities (i.e., movement of vessels, torpedoes, unmanned underwater vehicles and use of expended E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46148 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations munitions, ordnance, and other devices). Response 15: The Navy considered using a dynamic simulation model to estimate strike probability. However, the Navy determined, and NMFS concurs, that the use of historical data was a more appropriate way to analyze the potential for strike. The Navy’s strike probability analysis in the MITT FEIS/ OEIS is based upon actual data collected from historical use of vessels, in-water devices, and military expended materials, and the likelihood that these items may have the potential to strike an animal. This data accounts for real world variables over the course of many years, and any model would be expected to be less accurate than the use of actual data. There is no available science regarding the necessary functional parameters for a complex dynamic whale strike simulation model; there are large unknowns regarding the data that would be necessary such as the density, age classes, and behavior of large whales in the MITT Study Area; and there are no means to validate the output of a model given there is no empirical data (not strikes) to ‘‘seed the dynamic simulation.’’ Therefore, use of historical data from identical activities elsewhere and additional use of a probability analysis remain a more reasonable analytical approach. The Commission’s disagreement over the method the Navy has used to estimate strike probability is noted. Any increase in vessel movement, as discussed in Section 3.4.4.4.1 (Impacts from Vessels) of the MITT FEIS/OEIS, over the No Action is still well below areas such as the Southern California Range Complex (SOCAL) where the density of large whales and the number of Navy Activities is much higher than any of the MITT alternatives and yet strikes to large whales are still relatively rare in SOCAL. Additionally, while the number of training and testing activities is likely to increase, it is not expected to result in an appreciable increase in vessel use or transits since multiple activities usually occur from the same vessel. The Navy is not proposing substantive changes in the locations where vessels have been used over the last decade. There has never been a vessel strike to a whale during any active training or testing activities in the Study Area. A detailed analysis of strike data is also contained in Chapter 6 (Section 6.3.4, Estimated Take of Large Whales by Navy Vessel Strike) of the LOA application. The Navy does not anticipate vessel strikes to marine mammals during training or testing activities within the Study Area, nor VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 were takes by injury or mortality resulting from vessel strike predicted in the Navy’s analysis. Therefore, NMFS is not authorizing mysticete takes (by injury or mortality) from vessel strikes during the 5-year period of the MITT regulations. General Opposition Comment 16: One commenter expressed general opposition to Navy activities and NMFS’ issuance of an MMPA authorization. Response 16: NMFS appreciates the commenter’s concern for the marine environment. However, the MMPA directs NMFS to issue an incidental take authorization if certain findings can be made. NMFS has determined that the Navy’s training and testing activities will have a negligible impact on the affected species or stocks and, therefore, we plan to issue the requested MMPA authorization. Other Comment 17: One commenter asked about the effects of Navy activities on marine habitat and other resources not addressed in the proposed rule. Response 17: The MITT FEIS/OEIS addresses all potential impacts to the human environment, and is available online at https://www.mitt-eis.com. The MITT DEIS/OEIS was made available to the public on September 13, 2013 and was referenced in the proposed rule (79 FR 15388, March 19, 2014). Comment 18: One commenter requested additional details or elaboration regarding specific Navy training and testing activities (e.g., vessel type and speed, inwater detonations, Pierside Location maintenance, etc.). Response 18: Detailed information about each proposed activity (stressor, training or testing event, description, sound source, duration, and gepgraphic location) can be found in the MITT FEIS/OEIS. Comment 19: One commenter had several questions regarding information (e.g., species presence, distribution, stock abundance, ESA/MMPA status) presented in Table 6 (Marine Mammals with Possible or Confirmed Presence within the Study Area) and the Description of Marine Mammals in the Area of the Specified Activity section of the proposed rule. Response 19: As stated in the proposed rule, information on the status, occurrence and distribution, abundance, derivation of density estimates, and vocalizations of marine mammal species in the Study Area may be viewed in Chapters 3 and 4 of the LOA application (https:// PO 00000 Frm 00038 Fmt 4701 Sfmt 4700 www.nmfs.noaa.gov/pr/permits/ incidental/). This information was compiled by the Navy from peerreviewed literature, NMFS annual stock assessment reports (SARs) for marine mammals (https://www.nmfs.noaa.gov/ pr/species/mammals; Carretta et al., 2014; Allen and Angliss, 2014), and marine mammal surveys using acoustic and visual observations from aircraft and ships. Further information on the general biology and ecology of marine mammals is included in the MITT FEIS/ OEIS (https://www.mitt-eis.com.). Comment 20: One commenter questioned NMFS’ proposed authorization of take through issuance of a single 5-year LOA (multi-year LOA) rather than issuance of annual LOAs. Response 20: The ability to issue a multi-year LOA reduces administrative burdens on both NMFS and the Navy. In addition, a multi-year LOA would avoid situations where the last minute issuance of LOAs necessitates the commitment of extensive resources by the Navy for contingency planning. The regulations still: (1) Require the Navy to submit annual monitoring and exercise reports; (2) require that NMFS and the Navy hold annual monitoring and adaptive management meetings that ensure NMFS is able to evaluate the Navy’s compliance and marine mammal impacts with the same attention and frequency; and (3) allow for a LOA to be changed at any time, as appropriate, to incorporate any needed mitigation or monitoring measures developed through adaptive management, based on the availability of new information regarding military readiness activities or the marine mammals affected. If, through adaptive management, proposed modifications to the mitigation, monitoring, or reporting measures are substantial, NMFS would publish a notice of proposed LOA in the Federal Register and solicit public comment. Estimated Take In the Estimated Take section of the proposed rule, NMFS described the potential effects to marine mammals from active sonar and underwater detonations in relation to the MMPA regulatory definitions of Level A and Level B harassment (79 FR 15388, pages 15426–15430). That information has not changed and is not repeated here. It is important to note that, as Level B Harassment is interpreted here and quantified by the behavioral thresholds described below, the fact that a single behavioral pattern (of unspecified duration) is abandoned or significantly altered and classified as a Level B take does not mean, necessarily, that the E:\FR\FM\03AUR2.SGM 03AUR2 46149 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations fitness of the harassed individual is affected either at all or significantly, or that, for example, a preferred habitat area is abandoned. Further analysis of context and duration of likely exposures and effects is necessary to determine the impacts of the estimated effects on individuals and how those may translate to population-level impacts, and is included in the Analysis and Negligible Impact Determination. Tables 8 and 9 provide a summary of non-impulsive and impulsive thresholds to TTS and PTS for marine mammals. A detailed explanation of how these thresholds were derived is provided in the MITT FEIS/OEIS Criteria and Thresholds Technical Report (https://www.mitt-eis.com) and summarized in Chapter 6 of the Navy’s LOA application (https:// www.nmfs.noaa.gov/pr/permits/ incidental/). TABLE 8—ONSET TTS AND PTS THRESHOLDS FOR NON-IMPULSE SOUND Group Species Onset TTS Low-Frequency Cetaceans ............ Mid-Frequency Cetaceans ............. All mysticetes ................................ Most delphinids, beaked whales, medium and large toothed whales. Porpoises, Kogia spp. .................. 178 dB re 1μPa2-sec(LFII) ............ 178 dB re 1μPa2-sec(MFII) ........... 198 dB re 1μPa2-sec(LFII). 198 dB re 1μPa2-sec(MFII). 152 dB re 1μPa2-sec(HFII) ........... 172 dB re 1μPa2-secSEL (HFII). High-Frequency Cetaceans ........... Onset PTS LFII, MFII, HFII: New compound Type II weighting functions. TABLE 9—IMPULSIVE SOUND EXPLOSIVE THRESHOLDS FOR PREDICTING INJURY AND MORTALITY Slight Injury Group Species Mortality PTS Low-frequency Cetaceans ...... All mysticetes ......................... Mid-frequency Cetaceans ...... Most delphinids, medium and large toothed whales. Porpoises and Kogia spp ...... High-frequency Cetaceans ..... GI Tract Lung 187 dB SEL (LFII) or 230 dB Peak SPL. 187 dB SEL (MFII) or 230 dB Peak SPL. 161 dB SEL (HFII) or 201 dB Peak SPL. 237 dB SPL Equation 1 ..... Where: R = Risk (0–1.0) L = Received level (dB re: 1 mPa) B = Basement received level = 120 dB re: 1 mPa K = Received level increment above B where 50-percent risk = 45 dB re: 1 mPa A = Risk transition sharpness parameter = 10 (odontocetes) or 8 (mysticetes) • Acoustic (sonar and other active acoustic sources, explosives, weapons firing, launch and impact noise, vessel noise, aircraft noise); • Energy (electromagnetic devices); • Physical disturbance or strikes (vessels, in-water devices, military expended materials, seafloor devices); • Entanglement (fiber optic cables, guidance wires, parachutes); • Ingestion (munitions, military expended materials other than munitions); • Indirect stressors (impacts to habitat [sediment and water quality, air quality] or prey availability). NMFS has determined that two stressors could potentially result in the mstockstill on DSK4VPTVN1PROD with RULES2 Take Request The MITT FEIS/OEIS considered all training and testing activities proposed to occur in the Study Area that have the potential to result in the MMPA defined take of marine mammals. The potential stressors associated with these activities included the following: VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 PO 00000 Frm 00039 Fmt 4701 Sfmt 4700 incidental taking of marine mammals from training and testing activities within the Study Area: (1) Non-impulse acoustic stressors (sonar and other active acoustic sources) and (2) impulse acoustic stressors (explosives). Nonimpulse and impulse stressors have the potential to result in incidental takes of marine mammals by Level A (injury) or Level B (behavioral) harassment. NMFS also considered the potential for vessel strikes to impact marine mammals, and that assessment is presented below. Lethal takes of large whales and beaked whales, while not anticipated or predicted in the Navy’s acoustic analysis, were originally conservatively requested by the Navy for MITT training E:\FR\FM\03AUR2.SGM 03AUR2 ER03AU15.000</GPH> DRm = depth of the receiver (animal) in meters ER03AU15.012</GPH> Where: M = mass of the animals in kg Equation 2. 46150 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations and testing activities over the 5-year period of NMFS’ final authorization. That request was included in NMFS’ proposed rule (79 FR 15388, Take Request); however, NMFS has since made the decision not to authorize any lethal takes for MITT activities for reasons discussed below. Training and Testing Activities— Based on the Navy’s modeling and postmodel analysis (i.e., the acoustic analysis) (described in detail in Chapter 6 of their LOA application), Table 10 summarizes the authorized takes for training and testing activities for an annual maximum year (a notional 12month period when all annual and nonannual events could occur) and the summation over a 5-year period (annual events occurring five times and nonannual events occurring three times). Table 11 summarizes the authorized takes for training and testing activities by species from the modeling estimates. Predicted effects on marine mammals result from exposures to sonar and other active acoustic sources and explosions during annual training and testing activities. The acoustic analysis predicts the majority of marine mammal species in the Study Area would not be exposed to explosive (impulse) sources associated with training and testing activities that would exceed the current impact thresholds. No beaked whales are predicted in the acoustic analysis to be exposed to sound levels associated with PTS, other injury, or mortality. The Navy had originally conservatively requested authorization for beaked whale mortality (no more than 10 mortalities over 5 years) that might potentially result from exposure to active sonar, based on the few instances where sonar has been associated with strandings in other areas. That request was included in NMFS’ proposed rule (79 FR 15388, Take Request). However, after decades of the Navy conducting similar activities in the MITT Study Area without incident, neither the Navy nor NMFS expect stranding, injury, or mortality of beaked whales to occur as a result of Navy activities, and therefore, following consultation with the Navy, NMFS is not authorizing any Level A (injury or mortality) takes for beaked whales. In addition to a suite of mitigation intended to more broadly minimize impacts to marine mammals, the Navy and NMFS have a detailed Stranding Response Plan (described in the Mitigation section of this final rule and available at https://www.nmfs.noaa.gov/ pr/permits/incidental/) that outlines reporting, communication, and response protocols intended both to minimize the impacts of, and enhance the analysis of, any potential stranding in areas where the Navy operates. Vessel Strike—There has never been a vessel strike to a marine mammal during any active training or testing activities in the Study Area. A detailed analysis of strike data is contained in Chapter 6 (Section 6.3.4, Estimated Take of Large Whales by Navy Vessel Strike) of the LOA application. There have been Navy strikes of large whales in areas outside the Study Area, such as Hawaii and Southern California. However, these areas differ significantly from the Study Area given that both Hawaii and Southern California have a much higher number of Navy vessel activities and much higher densities of large whales. The Navy does not anticipate vessel strikes to marine mammals during training or testing activities within the Study Area, nor were takes by injury or mortality resulting from vessel strike predicted in the Navy’s analysis. Vessel strike to marine mammals is not associated with any specific training or testing activity but rather a limited, sporadic, and accidental result of Navy vessel movement. In order to account for the accidental nature of vessel strikes to large whales in general, and the potential risk from any vessel movement within the MITT Study Area, the Navy had originally conservatively requested authorization for large whale mortalities (no more than 5 mortalities over 5 years) that might potentially result from vessel strike during MITT training and testing activities over the 5year period of NMFS’ final authorization. That request was included in NMFS’ proposed rule (79 FR 15388, Take Request). However, after further consideration of the Navy’s ship strike analysis, the unlikelihood of a ship strike to occur and the fact that there has never been a ship strike to marine mammals in the Study Area, and following consultation with the Navy, NMFS is not authorizing takes (by injury or mortality) from vessel strikes during the 5-year period of the MITT regulations. The Navy has proposed measures (see Mitigation) to mitigate potential impacts to marine mammals from vessel strikes during training and testing activities in the Study Area. TABLE 10—SUMMARY OF AUTHORIZED ANNUAL AND 5-YEAR TAKES FOR TRAINING AND TESTING ACTIVITIES Training and testing activities MMPA Category Source Annual authorization 1 Level A .................... Impulse and Non-Impulse .................... Level B .................... Impulse and Non-Impulse .................... 5-Year authorization 2 56–Species specific data shown in Table 11. 81,906–Species specific data shown in Table 11. 280–Species specific data shown in Table 11 409,530–Species specific data shown in Table 11 1 These numbers constitute the total for an annual maximum year (a notional 12-month period when all annual and non-annual events could occur). 2 These numbers constitute the summation over a 5-year period with annual events occurring five times and non-annual events occurring three times. mstockstill on DSK4VPTVN1PROD with RULES2 TABLE 11—AUTHORIZED SPECIES-SPECIFIC TAKES FROM MODELING AND POST-MODEL ESTIMATES OF IMPULSIVE AND NON-IMPULSIVE SOURCE EFFECTS FOR ALL TRAINING AND TESTING ACTIVITIES Annually 1 Total over 5-year rule 2 Species Level B Blue whale ............................................... Fin whale .................................................. Humpback whale ..................................... Sei whale ................................................. Sperm whale ............................................ VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Level A 28 28 860 319 506 PO 00000 Frm 00040 Mortality 0 0 0 0 0 Fmt 4701 Sfmt 4700 Level B 0 0 0 0 0 E:\FR\FM\03AUR2.SGM 140 140 4,300 1,595 2,530 03AUR2 Level A Mortality 0 0 0 0 0 0 0 0 0 0 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 46151 TABLE 11—AUTHORIZED SPECIES-SPECIFIC TAKES FROM MODELING AND POST-MODEL ESTIMATES OF IMPULSIVE AND NON-IMPULSIVE SOURCE EFFECTS FOR ALL TRAINING AND TESTING ACTIVITIES—Continued Annually 1 Total over 5-year rule 2 Species Level B Bryde’s whale ........................................... Minke whale ............................................. Omura’s whale ......................................... Pygmy sperm whale ................................ Dwarf sperm whale .................................. Killer whale ............................................... False killer whale ..................................... Pygmy killer whale ................................... Short-finned pilot whale ........................... Melon-headed whale ................................ Bottlenose dolphin ................................... Pantropical spotted dolphin ..................... Striped dolphin ......................................... Spinner dolphin ........................................ Rough toothed dolphin ............................. Fraser’s dolphin ....................................... Risso’s dolphin ......................................... Cuvier’s beaked whale ............................. Blainville’s beaked whale ......................... Longman’s beaked whale ........................ Ginkgo-toothed beaked whale ................. Level A 398 101 103 5,579 14,217 84 555 105 1,815 2,085 741 12,811 3,298 589 1,819 2,572 505 22,541 4,426 1,924 3,897 Mortality 0 0 0 15 41 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Level B 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1,990 505 515 27,895 71,085 420 2,775 525 9,075 10,425 3,705 64,055 16,490 2,945 9,095 12,860 2,525 112,705 22,130 9,620 19,485 Level A Mortality 0 0 0 75 205 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 These numbers constitute the total for an annual maximum year (a notional 12-month period when all annual and non-annual events could occur). 2 These numbers constitute the summation over a 5-year period with annual events occurring five times and non-annual events occurring three times. mstockstill on DSK4VPTVN1PROD with RULES2 Marine Mammal Habitat The Navy’s proposed training and testing activities could potentially affect marine mammal habitat through the introduction of sound into the water column, impacts to the prey species of marine mammals, bottom disturbance, or changes in water quality. Each of these components was considered in Chapter 3 of the MITT FEIS/OEIS. Based on the information in the Marine Mammal Habitat section of the proposed rule (79 FR 15388, March 19, 2014; pages 15412–15414) and the supporting information included in the MITT FEIS/ OEIS, NMFS has determined that training and testing activities would not have adverse or long-term impacts on marine mammal habitat. In summary, expected effects to marine mammal habitat will include elevated levels of anthropogenic sound in the water column; short-term physical alteration of the water column or bottom topography; brief disturbances to marine invertebrates; localized and infrequent disturbance to fish; a limited number of fish mortalities; and temporary marine mammal avoidance. Analysis and Negligible Impact Determination Negligible impact is ‘‘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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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, as the severity of harassment may vary greatly depending on the context and duration of the behavioral response, many of which would not be expected to have deleterious impacts on the fitness of any individuals. In determining whether the expected takes will have a negligible impact, in addition to considering estimates of the number of marine mammals that might be ‘‘taken’’, NMFS must consider other factors, such as the likely nature of any responses (their intensity, duration, etc.), the context of any responses (critical reproductive time or location, migration, etc.), as well as the number and nature (e.g., severity) of estimated Level A harassment takes, the number of estimated mortalities, and the status of the species. The Navy’s specified activities have been described based on best estimates of the maximum amount of sonar and other acoustic source use or detonations that the Navy would conduct. There may be some flexibility in that the exact number of hours, items, or detonations may vary from year to year, but take totals are not authorized to exceed the PO 00000 Frm 00041 Fmt 4701 Sfmt 4700 5-year totals indicated in Table 11. We base our analysis and NID on the maximum number of takes authorized. To avoid repetition, we provide some general analysis immediately below that applies to all the species listed in Table 11, given that some of the anticipated effects (or lack thereof) 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, or groups of species where relevant similarities exist, to provide more specific information related to the anticipated effects on individuals 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 population. The Navy’s take request is based on its model and post-model analysis. In the discussions below, the ‘‘acoustic analysis’’ refers to the Navy’s modeling results and post-model analysis. The model calculates sound energy propagation from sonars, 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 received by a marine mammal exceeds the thresholds for effects. The model estimates are then further analyzed to consider animal E:\FR\FM\03AUR2.SGM 03AUR2 46152 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations avoidance and implementation of highly effective mitigation measures to prevent Level A harassment, resulting in final estimates of effects due to Navy training and testing. NMFS provided input to the Navy on this process and the Navy’s qualitative analysis is described in detail in Chapter 6 of their LOA application (https://www.nmfs.noaa.gov/ pr/permits/incidental/). Generally speaking, and especially with other factors being equal, 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 throughout species, individuals, or circumstances) and less severe effects from takes resulting from exposure to lower received levels. It is important to note that the requested and authorized number of 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 B or Level A harassment threshold) that would occur. Additionally, these instances may represent either a very brief exposure (seconds) or, in some cases, longer durations of exposure within a day. Depending on the location, duration, and frequency of activities, along with the distribution and movement of marine mammals, individual animals may be exposed to impulse or nonimpulse sounds at or above the harassment thresholds on multiple days. However, the Navy is currently unable to estimate the number of individuals that may be taken during training and testing activities. The model results estimate the total number of takes that may occur to a smaller number of individuals. While the model shows that an increased number of exposures may take place due to an increase in events/activities and ordnance, the types and severity of individual responses to training and testing activities are not expected to change. Behavioral Harassment As discussed previously in the proposed rule, marine mammals can respond to MFAS/HFAS in many different ways, a subset of which qualifies as harassment (see Behavioral Harassment section of proposed rule). One thing that the Level B harassment take estimates do not take into account is the fact that most marine mammals will likely avoid strong sound sources to one extent or another. Although an animal that avoids the sound source will likely still be taken in some instances (such as if the avoidance results in a missed opportunity to feed, interruption of reproductive behaviors, etc.), in other cases avoidance may result in fewer instances of take than were estimated or in the takes resulting from exposure to a lower received level than was estimated, which could result in a less severe response. For MFAS/ HFAS, the Navy provided information (Table 12) estimating the percentage of behavioral harassment that would occur within the 6-dB bins (without considering mitigation or avoidance). As mentioned above, an animal’s exposure to a higher received level is more likely to result in a behavioral response that is more likely to adversely affect the health of the animal. As illustrated below, the majority (about 80 percent, at least for hull-mounted sonar, which is responsible for most of the sonar takes) of calculated takes from MFAS result from exposures between 150 dB and 162 dB. Less than one percent of the takes are expected to result from exposures above 174 dB. Specifically, given a range of behavioral responses that may be classified as Level B harassment, to the degree that higher received levels are expected to result in more severe behavioral responses, only a small percentage of the anticipated Level B harassment from Navy activities might necessarily be expected to potentially result in more severe responses, especially when the distance from the source at which the levels below are received is considered (see Table 12). Marine mammals are able to discern the distance of a given sound source, and given other equal factors (including received level), they have been reported to respond more to sounds that are closer (DeRuiter et al., 2013). Further, the estimated number of responses do not reflect either the duration or context of those anticipated responses, some of which will be of very short duration, and other factors should be considered when predicting how the estimated takes may affect individual fitness. TABLE 12—NON-IMPULSIVE RANGES IN 6-DB BINS AND PERCENTAGE OF BEHAVIORAL HARASSMENTS Sonar bin MF1 (e.g., SQS–53; ASW hull mounted sonar) Received level Distance at which levels occur within radius of source (m) Percentage of behavioral harassments occurring at given levels Sonar bin MF4 (e.g., AQS–22; ASW dipping sonar) Distance at which levels occur within radius of source (m) Percentage of behavioral harassments occurring at given levels Sonar bin MF5 (e.g., SSQ–62; ASW sonobuoy) Sonar bin HF4 (e.g., SQQ–32; MIW sonar) Percentage of behavioral harassments occurring at given levels Distance at which levels occur within radius of source (m) Percentage of behavioral harassments occurring at given levels 18,000–13,000 13,000–7,600 7,600–2,800 2,800–900 900–500 500–250 250–100 100–<50 <50 <50 <50 <50 <50 <1 <1 12 26 15 21 20 6 <1 <1 <1 <1 <1 2,300–1,700 1,700–1,200 1,200–750 750–500 500–300 300–150 150–100 100–<50 <50 <50 <50 <50 <50 <1 <1 <1 5 17 34 20 24 <1 <1 <1 <1 <1 19,000–15,000 15,000–8,500 8,500–3,300 3,300–1,000 1,000–500 <1 <1 3 12 10 3,600–2,800 2,800–2,100 2,100–1,500 1,500–1,000 1,00–700 <1 <1 <1 3 10 Distance at which levels occur within radius of source (m) mstockstill on DSK4VPTVN1PROD with RULES2 Low Frequency Cetaceans 120 126 132 138 144 150 156 162 168 174 180 186 192 ≤SPL <126 ......... ≤SPL <132 ......... ≤SPL <138 ......... ≤SPL <144 ......... ≤SPL <150 ......... ≤SPL <156 ......... ≤SPL <162 ......... ≤SPL <168 ......... ≤SPL <174 ......... ≤SPL <180 ......... ≤SPL <186 ......... ≤SPL <192 ......... ≤ SPL <198 ........ 183,000–133,000 133,000–126,000 126,000–73,000 73,000–67,000 67,000–61,000 61,000–17,000 17,000–10,300 10,200 5,600 5,600–1,600 1,600–800 800–400 400–200 200–100 <1 <1 <3 <1 3 68 12 9 6 <1 <1 <1 <1 71,000–65,000 65,000–60,000 60,000–8,200 8,200–3,500 3,500–1,800 1,800–950 950–450 450–200 200–100 100–<50 <50 <50 <50 <1 <1 42 10 12 15 13 6 2 <1 <1 <1 <1 Mid-Frequency Cetaceans 120 126 132 138 144 ≤ ≤ ≤ ≤ ≤ SPL SPL SPL SPL SPL <126 <132 <138 <144 <150 VerDate Sep<11>2014 ........ ........ ........ ........ ........ 184,000–133,000 133,000–126,000 126,000–73,000 73,000–67,000 67,000–61,000 18:37 Jul 31, 2015 Jkt 235001 <1 <1 <1 <1 3 PO 00000 72,000–66,000 66,000–60,000 60,000–8,300 8,300–3,600 3,600–1,900 Frm 00042 Fmt 4701 <1 <1 41 10 12 Sfmt 4700 E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations 46153 TABLE 12—NON-IMPULSIVE RANGES IN 6-DB BINS AND PERCENTAGE OF BEHAVIORAL HARASSMENTS—Continued Sonar bin MF1 (e.g., SQS–53; ASW hull mounted sonar) Received level 150 156 162 168 174 180 186 192 ≤ ≤ ≤ ≤ ≤ ≤ ≤ ≤ SPL SPL SPL SPL SPL SPL SPL SPL <156 <162 <168 <174 <180 <186 <192 <198 ........ ........ ........ ........ ........ ........ ........ ........ mstockstill on DSK4VPTVN1PROD with RULES2 Sonar bin MF5 (e.g., SSQ–62; ASW sonobuoy) Sonar bin HF4 (e.g., SQQ–32; MIW sonar) Distance at which levels occur within radius of source (m) Percentage of behavioral harassments occurring at given levels Distance at which levels occur within radius of source (m) Percentage of behavioral harassments occurring at given levels Distance at which levels occur within radius of source (m) Percentage of behavioral harassments occurring at given levels Distance at which levels occur within radius of source (m) Percentage of behavioral harassments occurring at given levels 61,000–18,000 18,000–10,300 10,300–5,700 5,700–1,700 1,700–900 900–400 400–200 200–100 68 13 9 6 <1 <1 <1 <1 1,900–950 950–480 480–200 200–100 100–<50 <50 <50 <50 15 12 7 2 <1 <1 <1 <1 500–300 300–150 150–<50 <50 <50 <50 <50 <50 22 27 25 <1 <1 <1 <1 <1 700–450 450–250 250–150 150–100 100–<50 <50 <50 <50 21 32 19 9 6 <1 <1 <1 Although the Navy has been monitoring the effects of MFAS/HFAS on marine mammals since 2006, and research on the effects of MFAS is advancing, our understanding of exactly how marine mammals in the Study Area will respond to MFAS/HFAS is still growing. The Navy has submitted reports from more than 60 major exercises across Navy range complexes that indicate no behavioral disturbance was observed. One cannot conclude from these results that marine mammals were not harassed from MFAS/HFAS, as a portion of animals within the area of concern were not seen (especially those more cryptic, deep-diving species, such as beaked whales or Kogia spp.), the full series of behaviors that would more accurately show an important change is not typically seen (i.e., only the surface behaviors are observed), and some of the non-biologist watchstanders might not be well-qualified to characterize behaviors. However, one can say that the animals that were observed did not respond in any of the obviously more severe ways, such as panic, aggression, or anti-predator response. Diel Cycle As noted previously, 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). 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 VerDate Sep<11>2014 Sonar bin MF4 (e.g., AQS–22; ASW dipping sonar) 18:37 Jul 31, 2015 Jkt 235001 multiple-day anthropogenic activities. For example, just because at-sea exercises last 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 typically include assets that travel at high speeds (typically 10– 15 knots, or higher) and likely cover large areas that are relatively far from shore, in addition to the fact that marine mammals are 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. Additionally, 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 not to be likely for the majority of takes, does not mean that a behavioral response is necessarily sustained for multiple days, and still necessitates the consideration of likely duration and context to assess any effects on the individual’s fitness. Durations for non-impulsive activities utilizing tactical sonar sources vary and are fully described in Appendix A of the FEIS/OEIS. ASW training and testing exercises using MFAS/HFAS generally last for 2–16 hours, and may have intervals of non-activity in between. Because of the need to train in a large variety of situations, the Navy does not typically conduct successive MTEs or other ASW exercises in the same locations. Given the average length of ASW exercises (times of continuous sonar use) and typical vessel speed, combined with the fact that the majority of the cetaceans in the Study Area would not likely remain in an area for PO 00000 Frm 00043 Fmt 4701 Sfmt 4700 successive days, it is unlikely that an animal would be exposed to MFAS/ HFAS at levels 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 exercises are of a short duration (1–6 hours). 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. TTS As mentioned previously, 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. 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 more powerful MF sources used have center frequencies between 3.5 and 8 kHz and the other unidentified MF sources are, by definition, less than 10 kHz, which suggests that TTS induced by any of these MF sources would be in a frequency band somewhere between approximately 2 and 20 kHz. 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 20 and 100 kHz, which means that TTS could range up to 200 kHz; however, HF E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46154 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations systems are typically used less frequently and for shorter time periods than surface ship and aircraft MF systems, so TTS from these sources is even less likely). TTS from explosives would be broadband. Vocalization data for each species, which would inform how TTS might specifically interfere with communications with conspecifics, was provided in the LOA application. 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 document. 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 knots). In the TTS studies, 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, MFAS emits a nominal ping every 50 seconds, and incurring those levels of TTS is highly unlikely. 3. Duration of TTS (recovery time)— In the TTS laboratory studies, 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 MFAS/ HFAS training exercises in the 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 days (and any incident of TTS would likely be far less severe due to the short duration of the majority of the exercises and the speed of a typical vessel). Also, for the same reasons discussed in the 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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 might sustain would overlap with some of the frequency ranges of their vocalization types, the frequency range of TTS from MFAS (the source from which TTS would most likely be sustained because the higher source level and slower attenuation make it more likely that an animal would be exposed to a higher received level) would not usually span the entire frequency range of one vocalization type, much less span all types of vocalizations or other critical auditory cues. If impaired, marine mammals would typically be aware of their impairment and are sometimes able to implement behaviors to compensate (see Acoustic Masking or Communication Impairment section), though these compensations may incur energetic costs. Acoustic Masking or Communication Impairment Masking only occurs during the time of the signal (and potential secondary arrivals of indirect rays), versus TTS, which continues beyond the duration of the signal. Standard MFAS nominally pings every 50 seconds for hullmounted sources. For the sources for which we know the pulse length, most are significantly shorter than hullmounted active sonar, on the order of several microseconds to tens of microseconds. For hull-mounted active sonar, though some of the vocalizations that marine mammals make are less than one second long, there is only a 1 in 50 chance that they would occur exactly when the ping was received, and when vocalizations are longer than one second, only parts of them are masked. Alternately, when the pulses are only several microseconds long, the majority of most animals’ vocalizations would not be masked. Masking effects from MFAS/HFAS are expected to be minimal. If masking or communication impairment were to occur briefly, it would be in the frequency range of MFAS, which overlaps with some marine mammal 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 mimic the characteristics of any marine mammal’s vocalizations. PTS, Injury, or Mortality NMFS believes 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 PO 00000 Frm 00044 Fmt 4701 Sfmt 4700 close approach. Additionally, in the unlikely event that an animal approaches the sonar vessel at a close distance, NMFS believes that the mitigation measures (i.e., shutdown/ powerdown zones for MFAS/HFAS) 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 all ASW exercises) in addition to watchstanders on vessels to detect marine mammals for mitigation implementation. If a marine mammal is able to approach a surface vessel within the distance necessary to incur PTS, the likely speed of the vessel (nominal 10– 15 knots) 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 mentioned previously and in relation to TTS, the likely consequences to the health of an individual that incurs PTS can range from mild to more serious, depending upon the degree of PTS and the frequency band it is in, and many animals are able to compensate for the shift, although it may include energetic costs. As discussed previously, marine mammals (especially beaked whales) could potentially respond to MFAS at a received level lower than the injury threshold in a manner that indirectly results in the animals stranding. The exact mechanism of this potential response, behavioral or physiological, is not known. When naval exercises have been associated with strandings in the past, it has typically been when three or more vessels are operating simultaneously, in the presence of a strong surface duct, and in areas of constricted channels, semi-enclosed areas, and/or steep bathymetry. A combination of these environmental and operational parameters is not present in the MITT action. When this is combined with consideration of the number of hours of active sonar training that will be conducted and the nature of the exercises—which do not typically include the use of multiple hullmounted sonar sources—we believe that the probability is small that this will occur. Furthermore, given that there has never been a stranding in the Study Area associated with sonar use and based on the number of occurrences where strandings have been definitively associated with military sonar versus the number of hours of active sonar training that have been conducted, we believe that the probability is small that this will occur as a result of the Navy’s proposed training and testing activities. E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations Lastly, an active sonar shutdown protocol for strandings involving live animals milling in the water minimizes the chances that these types of events turn into mortalities. As stated previously, there have been no recorded Navy vessel strikes of any marine mammals during training or testing in the MITT Study Area to date, nor were takes by injury or mortality resulting from vessel strike predicted in the Navy’s analysis. mstockstill on DSK4VPTVN1PROD with RULES2 Important Marine Mammal Habitat No critical habitat for marine mammals species protected under the ESA has been designated in the MITT Study Area. There are also no known specific breeding or calving areas for marine mammals within the MITT Study Area. Group and Species-Specific Analysis Predicted harassment of marine mammals from exposures to sonar and other active acoustic sources and explosions during annual training and testing activities are shown in Table 11. The vast majority of predicted exposures are expected to be Level B harassment (non-injurious TTS and behavioral reactions) from sonar and other active acoustic sources at relatively low received levels (less than 156 dB) (Table 22). As mentioned earlier in the Analysis and Negligible Impact Determination section, an animal’s exposure to a higher received level is more likely to adversely affect the health of the animal. The acoustic analysis predicts the majority of marine mammal species in the Study Area would not be exposed to explosive (impulse) sources associated with training and testing activities that exceed the impulsive sound thresholds for injury (Table 9). Only dwarf sperm whale, pygmy sperm whale, Fraser’s dolphin, and pantropical spotted dolphin are predicted to have Level B (TTS) exposures resulting from explosives, and only small numbers of dwarf sperm whales and pygmy sperm whales are expected to have injurious take (PTS or minor tissue damage from explosives) resulting from sonar and other active acoustic sources and explosions. There are no lethal takes predicted for any marine mammal species for the MITT activities. The analysis below may in some cases (e.g., mysticetes, dolphins) address species collectively if they occupy the same functional hearing group (i.e., low, mid, and high-frequency cetaceans and pinnipeds in water), have similar hearing capabilities, and/or are known to generally behaviorally respond similarly to acoustic stressors. Where VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 there are meaningful differences between species or stocks, or groups of species, in anticipated individual responses to activities, impact of expected take on the population due to differences in population status, or impacts on habitat, they will either be described within the section or the species will be included as a separate sub-section. See the Brief Background on Sound section in the proposed rule for a description of marine mammal functional hearing groups as originally designated by Southall et al. (2007). Mysticetes—The Navy’s acoustic analysis predicts 1,837 takes (Level B harassment) may occur from sonar and other active acoustic stressors associated with mostly training and some testing activities in the Study Area each year. The acoustic analysis indicates up to 28 annual instances of Level B harassment (24 TTS and 4 behavioral reactions) of fin whales, up to 28 annual instances of Level B harassment (25 TTS and 3 behavioral reactions) of blue whales, up to 319 annual instances of Level B harassment (258 TTS and 61 behavioral reactions) of sei whales, up to 860 annual instances of Level B harassment (679 TTS and 181 behavioral reactions) of humpback whales, up to 398 annual instances of Level B harassment (219 TTS and 79 behavioral reactions) of Bryde’s whales, up to 101 annual instances of Level B harassment (81 TTS and 20 behavioral reactions of minke whales, and up to 103 annual instances of Level B harassment (84 TTS and 19 behavioral reactions) of Omura’s whales. Of these species, humpback, blue, fin, and sei whales are listed as endangered under the ESA and depleted under the MMPA. NMFS has designated two Pacific stocks for blue whales (Eastern North Pacific and Central North Pacific) (Carretta et al., 2014), with blue whales in the Study Area most likely part of the Central North Pacific stock. NMFS has designated four Pacific stocks for humpback whales (Western North Pacific, Central North Pacific, California/Oregon/Washington, and American Samoa) (Carretta et al., 2014; Allen and Angliss, 2014), and while stock structure is not completely known for the Study Area, it is most likely that humpback whales here are part of the Western North Pacific and/or Central North Pacific stock. Although NMFS has designated Pacific stocks for fin, sei, Bryde’s, minke, and Omura’s whales (Carretta et al., 2014; Allen and Angliss, 2014), little is known about the stock structure for these species in the MITT Study Area and NMFS currently has not designated any stocks specific to the MITT Study Area for these species. PO 00000 Frm 00045 Fmt 4701 Sfmt 4700 46155 The estimates given above represent the total number of exposures and not necessarily the number of individuals exposed, as a single individual may be exposed multiple times over the course of a year. In the ocean, the use of sonar and other active acoustic sources is transient and is unlikely to repeatedly expose the same population of animals over a short period. Around heavily trafficked Navy ports and on fixed ranges, the possibility is greater for animals that are resident during all or part of the year to be exposed multiple times to sonar and other active acoustic sources. However, as discussed in the proposed rule, because neither the vessels nor the animals are stationary, significant long-term effects from repeated exposure are not expected. Level B harassment is anticipated to be in the form of non-TTS behavioral responses and TTS, and no injurious (Level A harassment) takes of mysticete whales from sonar and other active acoustic stressors or explosives are expected. The majority of acoustic effects to mysticetes from sonar and other active sound sources during training and testing activitites would be primarily from anti-submarine warfare events involving surface ships and hull mounted (mid-frequency) sonar. 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 grounds (i.e., breeding or feeding). Reactions may include alerting, breaking off feeding dives and surfacing, diving or swimming away, or no response at all (Richardson, 1995; Nowacek, 2007; Southall et al., 2007). 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. It 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. Additionally, migrating animals may ignore a sound source, or divert around the source if it is in their path. Specific to U.S. Navy systems using low frequency sound, studies were undertaken in 1997–98 pursuant to the Navy’s Low Frequency Sound Scientific Research Program. These studies found only short-term responses to low frequency sound by mysticetes (fin, blue, and humpback whales) including E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46156 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations changes in vocal activity and avoidance of the source vessel (Clark, 2001; Miller et al., 2000; Croll et al., 2001; Fristrup et al., 2003; Nowacek et al., 2007). Baleen whales exposed to moderate low-frequency signals demonstrated no variation in foraging activity (Croll et al., 2001). Low-frequency signals of the Acoustic Thermometry of Ocean Climate sound source were not found to affect dive times of humpback whales in Hawaiian waters (Frankel and Clark, 2000). Specific to mid-frequency sound, ´ studies by Melcon et al. (2012) in the Southern California Bight found that the likelihood of blue whale low-frequency calling (usually associated with feeding behavior) decreased with an increased level of mid-frequency sonar, beginning at a SPL of approximately 110–120 dB re 1 mPa. However, 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. Preliminary results from the 2010–2011 field season of an ongoing behavioral response study 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 mild and there was a quick return to their baseline activity (Southall et al., 2012b). Blue whales responded to a mid-frequency sound source, with a source level between 160 and 210 dB re 1 mPa at 1 m and a received sound level up to 160 dB re 1 mPa, by exhibiting generalized avoidance responses and changes to dive behavior during controlled exposure experiments (CEE) (Goldbogen et al., 2013). However, reactions were not consistent across individuals based on received sound levels alone, and likely were the result of a complex interaction between sound exposure factors such as proximity to sound source and sound type (midfrequency sonar simulation vs. pseudorandom noise), environmental conditions, and behavioral state. Surface feeding whales did not show a change in behavior during CEEs, but deep feeding and non-feeding whales showed temporary reactions that quickly abated after sound exposure. Distances of the sound source from the whales during CEEs were sometimes less than a mile. Furthermore, the more dramatic reactions reported by Goldbogen et al. (2013) were from non-sonar like signals, a pseudorandom noise that could likely have been a novel signal to blue whales. The preliminary findings from ´ Goldbogen et al. (2013) and Melcon et VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 al. (2012) are generally consistent with the Navy’s criteria and thresholds for predicting behavioral effects to mysticetes from sonar and other active acoustic sources used in the quantitative acoustic effects analysis for MITT. The behavioral response function predicts a probability of a substantive behavioral reaction for individuals exposed to a received SPL of 120 dB re 1 mPa or greater, with an increasing probability of reaction with increased received level as ´ demonstrated in Melcon et al. (2012). High-frequency systems are not within mysticetes’ ideal hearing range and it is unlikely that they would cause a significant behavioral reaction. Most Level B harassments to mysticetes from sonar would result from received levels less than 156 dB SPL. Therefore, the majority of Level B 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 short duration. As mentioned earlier in the Analysis and Negligible Impact Determination section, we anticipate more severe effects from takes when animals are exposed to higher received levels. Most low-frequency (mysticetes) cetaceans observed in studies usually avoided sound sources at levels of less than or equal to 160 dB re 1mPa. Occasional behavioral reactions are unlikely to cause long-term consequences for individual animals or populations. Even if sound exposure were to be concentrated in a relatively small geographic area over a long period of time (e.g., days or weeks during major training exercises), we would expect that some individual whales would avoid areas where exposures to acoustic stressors are at higher levels. For example, Goldbogen et al. (2013) indicated some horizontal displacement of deep foraging blue whales in response to simulated MFA sonar. Given these animal’s mobility and large ranges, we would expect these individuals to temporarily select alternative foraging sites nearby until the exposure levels in their initially selected foraging area have decreased. Therefore, even temporary displacement from initially selected foraging habitat is not expected to impact the fitness of any individual animals because we would expect equivalent foraging to be available in close proximity. Because we do not expect any fitness consequences from any individual animals, we do not expect any population level effects from these behavioral responses. As explained above, recovery from a threshold shift (TTS) can take a few minutes to a few days, depending on the PO 00000 Frm 00046 Fmt 4701 Sfmt 4700 exposure duration, sound exposure level, and the magnitude of the initial shift, with larger threshold shifts and longer exposure durations requiring longer recovery times (Finneran et al., 2005; Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney et al., 2009b). However, large threshold shifts are not anticipated for these activities because of the unlikelihood that animals will remain within the ensonified area (due to the short duration of the majority of exercises, the speed of the vessels, and the short distance within which the animal would need to approach the sound source) at high levels for the duration necessary to induce larger threshold shifts. Threshold shifts do not necessarily affect all hearing frequencies equally, so some threshold shifts may not interfere with an animal’s hearing of biologically relevant sounds. Furthermore, the implementation of mitigation and the sightability of mysticetes (due to their large size) reduces the potential for a significant behavioral reaction or a threshold shift to occur. There has never been a vessel strike to a whale during any active training or testing activities in the Study Area. A detailed analysis of strike data is contained in Chapter 6 (Section 6.3.4, Estimated Take of Large Whales by Navy Vessel Strike) of the LOA application. The Navy does not anticipate vessel strikes to marine mammals during training or testing activities within the Study Area, nor were takes by injury or mortality resulting from vessel strike predicted in the Navy’s analysis. Therefore, NMFS is not authorizing mysticete takes (by injury or mortality) from vessel strikes during the 5-year period of the MITT regulations. There is no designated critical habitat for mysticetes in the Study Area. There are also no areas of specific importance for reproduction, calving, or feeding for mysticetes in the Study Area. Sperm Whales—The Navy’s acoustic analysis indicates that 506 instances of Level B harassment of sperm whales may occur each year from sonar or other active acoustic stressors during training and testing activities. These Level B takes are anticipated to be in the form of TTS (54) and behavioral reactions (452) and no injurious takes of sperm whales from sonar and other active acoustic stressors or explosives are requested or proposed for authorization. Although NMFS has designated Pacific stocks for sperm whales (Carretta et al., 2014; Allen and Angliss, 2014), little is known about the stock structure for this species in the MITT Study Area and NMFS currently has not designated any E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations sperm whale stocks specific to the MITT Study Area. Sperm whales have shown resilience to acoustic and human disturbance, although they may react to sound sources and activities within a few kilometers. Sperm whales that are exposed to activities that involve the use of sonar and other active acoustic sources may alert, ignore the stimulus, avoid the area by swimming away or diving, or display aggressive behavior (Richardson, 1995; Nowacek, 2007; Southall et al., 2007). Some (but not all) sperm whale vocalizations might overlap with the MFAS/HFAS TTS frequency range, which could temporarily decrease an animal’s sensitivity to the calls of conspecifics or returning echolocation signals. However, as noted previously, NMFS does not anticipate TTS of a long duration or severe degree to occur as a result of exposure to MFAS/HFAS. Recovery from a threshold shift (TTS) can take a few minutes to a few days, depending on the exposure duration, sound exposure level, and the magnitude of the initial shift, with larger threshold shifts and longer exposure durations requiring longer recovery times (Finneran et al., 2005; Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney et al., 2009b). However, large threshold shifts are not anticipated for these activities because of the unlikelihood that animals will remain within the ensonified area (due to the short duration of the majority of exercises and the speed of the vessels) at high levels for the duration necessary to induce larger threshold shifts. Also, 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. Threshold shifts do not necessarily affect all hearing frequencies equally, so some threshold shifts may not interfere with an animal’s hearing of biologically relevant sounds. No sperm whales are predicted to be exposed to MFAS/HFAS sound levels associated with PTS or injury. The majority of Level B takes are expected to be in the form of milder responses (low-level exposures) and of a generally short duration. Overall, the number of predicted behavioral reactions are unlikely to cause long-term consequences for individual animals or populations. The MITT activities are not expected to occur in an area/time of specific importance for reproductive, feeding, or other known critical behaviors for sperm whales. Consequently, the activities are not VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 expected to adversely impact rates of recruitment or survival of sperm whales. Sperm whales are listed as endangered under the ESA (and depleted under the MMPA); however, there is no designated critical habitat in the Study Area. There has never been a vessel strike to a sperm whale during any active training or testing activities in the Study Area. A detailed analysis of strike data is contained in Chapter 6 (Section 6.3.4, Estimated Take of Large Whales by Navy Vessel Strike) of the LOA application. The Navy does not anticipate vessel strikes to marine mammals during training or testing activities within the Study Area, nor were takes by injury or mortality resulting from vessel strike predicted in the Navy’s analysis. Therefore, NMFS is not authorizing sperm whale takes (by injury or mortality) from vessel strikes during the 5-year period of the MITT regulations. Pygmy and Dwarf Sperm Whale—The Navy’s acoustic analysis predicts Level B harassment (non-TTS behavioral responses and TTS) of 5,579 pygmy sperm whales and 14,217 dwarf sperm whales may occur annually from sonar and other active acoustic stressors and explosives associated with training and testing activities in the Study Area. These estimates represents the total number of exposures and not necessarily the number of individuals exposed, as a single individual may be exposed multiple times over the course of a year. Of the Level B takes, 5,467 pygmy sperm whale and 13,901 dwarf sperm whale takes are predicted to be in the form of TTS from mainly MFAS/ HFAS. The Navy’s acoustic analysis (factoring in the post-model correction for avoidance and mitigation) also indicates that 15 injurious (Level A harassment) takes of pygmy sperm whale and 41 injurious (Level A harassment) takes of dwarf sperm whale may occur annually from active sonar. Although NMFS has designated Pacific stocks for pygmy and dwarf sperm whales (Carretta et al., 2014), little is known about the stock structure for these species in the MITT Study Area and NMFS currently has not designated any pygmy and dwarf sperm whale stocks specific to the MITT Study Area. Recovery from a threshold shift (TTS; partial hearing loss) can take a few minutes to a few days, depending on the exposure duration, sound exposure level, and the magnitude of the initial shift, with larger threshold shifts and longer exposure durations requiring longer recovery times (Finneran et al., 2005; Mooney et al., 2009a; Mooney et PO 00000 Frm 00047 Fmt 4701 Sfmt 4700 46157 al., 2009b; Finneran and Schlundt, 2010). An animal incurring PTS would not fully recover. However, large degrees of threshold shifts (PTS or TTS) are not anticipated for these activities because of the unlikelihood that animals will remain within the ensonified area (due to the short duration of the majority of exercises, the speed of the vessels, and the short distance within which the animal would need to approach the sound source) at high levels for the duration necessary to induce larger threshold shifts. Threshold shifts do not necessarily affect all hearing frequencies equally, so some threshold shifts may not interfere with an animal hearing biologically relevant sounds. The likely consequences to the health of an individual that incurs PTS can range from mild to more serious, depending upon the degree of PTS and the frequency band it is in, and many animals are able to compensate for the shift, although it may include energetic costs. Furthermore, likely avoidance of intense activity and sound coupled with mitigation measures would further reduce the potential for more-severe PTS exposures to occur. If a pygmy or dwarf sperm whale is able to approach a surface vessel within the distance necessary to incur PTS, the likely speed of the vessel (nominal 10–15 knots) 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. Some Kogia spp. vocalizations might overlap with the MFAS/HFAS TTS frequency range (2–20 kHz), but the limited information for Kogia spp. indicates that their clicks are at a much higher frequency and that their maximum hearing sensitivity is between 90 and 150 kHz. Research and observations on Kogia spp. are limited. These species tend to avoid human activity and presumably anthropogenic sounds. Pygmy and dwarf sperm whales may startle and leave the immediate area of activity, reducing potential impacts. Pygmy and dwarf sperm whales have been 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). Based on their tendency to avoid acoustic stressors (e.g., quick diving and other vertical avoidance maneuvers) coupled with the short duration and intermittent nature (e.g., sonar pings during ASW activities occur about every 50 seconds) of the majority of training and testing exercises and the speed of the Navy vessels E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46158 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations involved, it is unlikely that animals would receive multiple exposures over a short period of time, allowing animals to recover lost resources (e.g., food) or opportunities (e.g., mating). It is worth noting that the amount of explosive and acoustic energy entering the water may be overestimated, as many explosions actually occur upon impact with above-water targets. However, sources such as these were modeled as exploding at 1-meter depth. The predicted effects to Kogia spp. are expected to be mostly temporary and unlikely to cause long-term consequences for individual animals or populations. The MITT activities are not expected to occur in an area/time of specific importance for reproductive, feeding, or other known critical behaviors. Pacific stocks of Kogia are not depleted under the MMPA. Consequently, the activities are not expected to adversely impact rates of recruitment or survival of pygmy and dwarf sperm whales. Beaked Whales—The Navy’s acoustic analysis predicts Level B harassment of four species of beaked whale annually: 22,541 Cuvier’s beaked whales; 4,426 Blainville’s beaked whale; 1,924 Longman’s beaked whale; and 3,897 ginko-toothed beaked whales. These estimates represent the total number of exposures and not necessarily the number of individuals exposed, as a single individual may be exposed multiple times over the course of a year. These takes are anticipated to be in the form of mainly non-TTS behavioral harassment and some TTS, and no injurious takes of beaked whales from sonar and active acoustic stressors or explosives were predicted. Of the Level B takes, 308 Cuvier’s beaked whale, 73 Blainville’s beaked whale, 29 Longman’s beaked whale, and 62 ginkotoothed beaked whale takes are predicted to be in the form of TTS from sonar and other active acoustic sources. Although NMFS has designated Pacific stocks for Cuvier’s, Blainville’s, and Longman’s beaked whales (Carretta et al., 2014; Allen and Angliss, 2014), little is known about the stock structure for beaked whales in the MITT Study Area and NMFS currently has not designated any beaked whale stocks specific to the MITT Study Area. Of note, the number of beaked whales behaviorally harassed by exposure to MFAS/HFAS is generally higher than the other species because of the low Level B harassment threshold, which essentially makes the ensonified area of effects significantly larger than for the other species. Beaked whales have unique criteria based on specific data that show these animals to be especially VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 sensitive to sound (McCarthy et al., 2011; Tyack et al., 2011). Beaked whale non-impulsive behavioral criteria are used unweighted (i.e., without weighting the received level before comparing it to the threshold (see Finneran and Jenkins, 2012)). The Navy has adopted an unweighted 140 dB re 1 mPa SPL threshold for significant behavioral effects for all beaked whales. The fact that the threshold is a step function and not a curve (and assuming uniform density) means that the vast majority of the takes occur in the very lowest levels that exceed the threshold (it is estimated that approximately 80 percent of the takes are from exposures of 140 dB to 146 dB), which means that the anticipated effects for the majority of exposures are not expected to be severe (As mentioned above, an animal’s exposure to a higher received level is more likely to result in a behavioral response that is more likely to adversely affect the health of an animal). Further, Moretti et al. (2014) recently derived an empirical risk function for Blainville’s beaked whale that predicts there is a 0.5 probability of disturbance at a received level of 150 dB (CI: 144–155), suggesting that in some cases the current Navy step function over-estimate the effects of an activity using sonar on beaked whales. Irrespective of the Moretti et al. (2014) risk function, NMFS’ analysis assumes that all of the beaked whale Level B takes that are proposed for authorization will occur, and we base our negligible impact determination, in part, on the fact that these exposures would mainly occur at the very lowest end of the 140dB behavioral harassment threshold where behavioral effects are expected to be much less severe and generally temporary in nature. Behavioral responses of beaked whales can range from a mild orienting response, or a shifting of attention, to flight and panic (Richardson, 1995; Nowacek, 2007; Southall et al., 2007; Finneran and Jenkins, 2012). Research has also shown that beaked whales are sensitive to the presence of human activity (Tyack et al., 2011; Pirotta et al., 2012). 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). Some beaked whale vocalizations may overlap with the MFAS/HFAS TTS frequency range (2–20 kHz); however, as noted above, NMFS does not anticipate TTS of a PO 00000 Frm 00048 Fmt 4701 Sfmt 4700 serious degree or extended duration to occur as a result of exposure to MFA/ HFAS. Recovery from a threshold shift (TTS) can take a few minutes to a few days, depending on the exposure duration, sound exposure level, and the magnitude of the initial shift, with larger threshold shifts and longer exposure durations requiring longer recovery times (Finneran et al., 2005; Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney et al., 2009b). However, large threshold shifts are not anticipated for these activities because of the unlikelihood that animals will remain within the ensonified area (due to the short duration of the majority of exercises, the speed of the vessels, and the short distance within which the animal would need to approach the sound source) at high levels for the duration necessary to induce larger threshold shifts. Threshold shifts do not necessarily affect all hearing frequencies equally, so some threshold shifts may not interfere with an animal’s hearing of biologically relevant sounds. No beaked whales are predicted in the acoustic analysis to be exposed to sound levels associated with PTS, other injury, or mortality. After decades of the Navy conducting similar activities in the MITT Study Area without incident, NMFS does not expect stranding, injury, or mortality of beaked whales to occur as a result of Navy activities. Therefore, NMFS is not authorizing any Level A (injury or mortality) takes for beaked whales. Additionally, through the MMPA process (which allows for adaptive management), NMFS and the Navy will determine the appropriate way to proceed in the event that a causal relationship were to be found between Navy activities and a future stranding. NMFS also considered New et al. (2013) and their mathematical model simulating a functional link between foraging energetics and requirements for survival and reproduction for 21 species of beaked whales. However, NMFS concluded that the New et al. (2013) model lacks critical data and accurate inputs necessary to form valid conclusions specifically about impacts of anthropogenic sound from Navy activities on specific beaked whale populations. The study itself notes the need for ‘‘future research,’’ identifies ‘‘key data needs’’ relating to input parameters that ‘‘particularly affected’’ the model results, and states only that the use of the model ‘‘in combination with more detailed research’’ could help predict the effects of management actions on beaked whale species. In short, information is not currently available to specifically support the use E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations of this model in a project-specific evaluation of the effects of Navy activities on the impacted beaked whale species in MITT. 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 mid-frequency sonar use. 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 midfrequency sonar. Received levels of sonar on the tag increased to a maximum of 138 dB re 1mPa, 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. 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 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; Moretti et al., 2009, 2010; Tyack et al., 2010, 2011; McCarthy et al., 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., 2013). 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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 ramp-up) may have been a significant factor. The study itself found the results inconclusive and meriting further investigation. Populations of beaked whales and other odontocetes in the Bahamas and other Navy fixed ranges that have been operating for tens of years appear to be stable. Significant behavioral reactions 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 (Tyack et al., 2011; De Ruiter et al., 2013; Manzano-Roth et al., 2013; Moretti et al., 2014). 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 more frequently than the MITT Study Area, 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. Finally, results from passive acoustic monitoring estimated regional Cuvier’s beaked whale densities were higher than indicated by the NMFS’s broad scale visual surveys for the U.S. west coast (Hildebrand and McDonald, 2009). Based on the findings above, it is clear that the Navy’s longterm ongoing use of sonar and other active acoustic sources has not precluded beaked whales from also continuing to inhabit those areas. In summary, based on the best available science, the Navy and NMFS believe that beaked whales that exhibit a significant TTS or behavioral reaction due to sonar and other active acoustic PO 00000 Frm 00049 Fmt 4701 Sfmt 4700 46159 testing activities would generally not have long-term consequences for individuals or populations. Claridge (2013) speculates that sonar use in a Bahamas range could have ‘‘a possible population-level effect’’ on beaked whales based on lower abundance in comparison to control sites. However, the study suffers from several shortcomings and incorrectly assumes that the Navy range and control sites were identical. The author also acknowledged that ‘‘information currently available cannot provide a quantitative answer to whether frequent sonar use at [the Bahamas range] is causing stress to resident beaked whales,’’ and cautioned that the outcome of ongoing studies ‘‘is a critical component to understanding if there are population-level effects.’’ Moore and Barlow (2013) have noted a decline in beaked whale populations in a broad area of the Pacific Ocean area out to 300 nm from the coast and extending from the Canadian-U.S. border to the tip of Baja Mexico. There are scientific caveats and limitations to the data used for that analysis, as well as oceanographic and species assemblage changes on the U.S. Pacific coast not thoroughly addressed. Interestingly, however, in the small portion of that area overlapping the Navy’s SOCAL Range Complex, longterm residency by individual Cuvier’s beaked whales and higher densities provide indications that the proposed decline noted elsewhere is not apparent where the Navy has been intensively training and testing with sonar and other systems for decades. There is no direct evidence that routine Navy training and testing spanning decades has negatively impacted marine mammal populations at any Navy range complex. In at least three decades of similar activities, only one instance of injury to marine mammals (March 4, 2011; three longbeaked common dolphin at Silver Strand Training Complex) has been documented as a result of training or testing using an impulse source (underwater explosion) and the Navy implemented more stringent mitigation measures as a result of this incident. Stranding events coincident with Navy MFAS use in which exposure to sonar is believed to have been a contributing factor were detailed in the Stranding and Mortality section of the proposed rule (FR 79 15437). However, for some of these stranding events, a causal relationship between sonar exposure and the stranding could not be clearly established (Cox et al., 2006). In other instances, sonar was considered only one of several factors that, in their E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46160 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations aggregate, may have contributed to the stranding event (Freitas, 2004; Cox et al., 2006). On March 24, 2015, a Cuvier’s beaked whale stranded, and eventually died, near Bile Bay, Merizo Guam. The Navy confirmed that nonMTE sonar exercises took place in the MIRC from March 23–27, 2015. A necropsy was performed by the Guam Department of Agriculture, Division of Aquatics and Wildlife with assistance from NOAA. Results of the necropsy have yet to be released and no causal relationship between the stranding and Navy activities has been determined at this time. Because of the association between tactical MFA 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 a suite of mitigation measures intended to more broadly minimize impacts to marine mammals, the Navy and NMFS have a detailed Stranding Response Plan that outlines reporting, communication, and response protocols intended both to minimize the impacts of, and enhance the analysis of, any potential stranding in areas where the Navy operates. The MITT training and testing activities are not expected to occur in an area/time of specific importance for reproductive, feeding, or other known critical behaviors for beaked whales. The degree of predicted Level B harassment is expected to be mild, and no beaked whales are predicted in the acoustic analysis to be exposed to sound levels associated with PTS, other injury, or mortality. Consequently, the activities are not expected to adversely impact rates of recruitment or survival of beaked whales. Social Pelagic Species (Small Whales)—The Navy’s acoustic analysis predicts that the following numbers of Level B behavioral harassments of the associated species will occur annually: 84 killer whales; 555 false killer whales; 105 pygmy killer whales; 1,815 shortfinned pilot whales; and 2,085 melonheaded whales; including the following numbers of TTS, respectively: 15, 101, 19, 334, and 448. These estimates represent the total number of exposures and not necessarily the number of individuals exposed, as a single individual may be exposed multiple times over the course of a year. Behavioral responses of social pelagic small whales can range from a mild orienting response, or a shifting of attention, to flight and panic (Richardson, 1995; Nowacek, 2007; Southall et al., 2007; Finneran and VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 Jenkins, 2012). No injurious takes from active acoustic stressors or explosives are requested or proposed for authorization. Although NMFS has designated Pacific stocks for killer whales, false killer whales, pygmy killer whales, short-finned pilot whales, and melonheaded whales (Carretta et al., 2014; Allen and Angliss, 2014), little is known about the stock structure for these species in the MITT Study Area and NMFS currently has not designated any stocks for these species specific to the MITT Study Area. As mentioned previously, TTS from MFAS is anticipated to occur primarily in the 2–20 kHz range. If any individuals of these species were to experience TTS from MFAS/HFAS, the TTS would likely overlap with some of the vocalizations of conspecifics, and not with others. However, as noted previously, NMFS does not anticipate TTS of a long duration or severe degree to occur as a result of exposure to MFA/ HFAS. Recovery from a threshold shift (TTS) can take a few minutes to a few days, depending on the exposure duration, sound exposure level, and the magnitude of the initial shift, with larger threshold shifts and longer exposure durations requiring longer recovery times (Finneran et al., 2005; Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney et al., 2009b). However, large threshold shifts are not anticipated for these activities because of the unlikelihood that animals will remain within the ensonified area (due to the short duration of the majority of exercises, the speed of the vessels, and the short distance within which the animal would need to approach the sound source) at high levels for the duration necessary to induce larger threshold shifts. Threshold shifts do not necessarily affect all hearing frequencies equally, so some threshold shifts may not interfere with an animal’s hearing of biologically relevant sounds. Controlled exposure experiments in 2007 and 2008 in the Bahamas recorded responses of false killer whales, shortfinned pilot whales, and melon-headed whales to simulated MFA sonar (De Ruiter et al., 2013). The responses to exposures between species were variable. After hearing each MFAS signal, false killer whales were found to ‘‘increase their whistle production rate and made more-MFAS-like whistles’’ (De Ruiter et al., 2013). In contrast, melon-headed whales had ‘‘minor transient silencing’’ after each MFAS signal, while pilot whales had no apparent response. Pilot whales or false killer whales in the Bahamas showed an avoidance PO 00000 Frm 00050 Fmt 4701 Sfmt 4700 response to controlled exposure playbacks (Southall et al., 2009). Consistent with the findings of other previous research (see, for example Southall et al., 2007), De Ruiter et al., (2013b) found the responses were variable by species and with the context of the sound exposure. The assumption is that odontocete species in general, including those in the MITT Study Area, would have similar variable responses. Research and observations show that if killer whales 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. Killer whales 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. Killer whales that are exposed to activities that involve the use of sonar and other active acoustic sources may alert, ignore the stimulus, change their behaviors or vocalizations, avoid the sound source by swimming away or diving, or be attracted to the sound source. Research has demonstrated that killer whales may routinely move over long large distances (Andrews and Matkin, 2014; Fearnbach et al., 2013). In a similar documented long-distance movement, an Eastern North Pacific Offshore stock killer whale tagged off San Clemente Island, California, moved (over a period of 147 days) to waters off northern Mexico, then north to Cook Inlet, Alaska, and finally (when the tag ceased transmitting) to coastal waters off Southeast Alaska (Falcone and Schorr, 2014). Given these findings, temporary displacement due to avoidance of training and testing activities are therefore unlikely to have biological significance to individual animals. Long-term consequences to individual killer whales or populations are not likely due to exposure to sonar or other active acoustic sources. Population-level consequences are not expected. The MITT activities are not expected to occur in an area/time of specific importance for reproductive, feeding, or other known critical behaviors for social pelagic species. Consequently, the activities are not expected to adversely impact rates of recruitment or survival of these species. Dolphins—The Navy’s acoustic analysis predicts the following numbers of Level B harassment annually: 741 bottlenose dolphin; 12,811 pantropical spotted dolphin; 3,298 striped dolphin; 589 spinner dolphin; 1,819 rough toothed dolphin; 2,572 Fraser’s dolphin; E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations and 505 Risso’s dolphin. These estimates represent the total number of exposures and not necessarily the number of individuals exposed, as a single individual may be exposed multiple times over the course of a year. The majority of takes are anticipated to be by non-TTS behavioral harassment in the form of milder responses (low received levels and of a short duration) to sonar and other active acoustic sources. No injurious takes of dolphins from active acoustic stressors or explosives are requested or proposed for authorization. Behavioral responses can range from alerting, to changing their behavior or vocalizations, to avoiding the sound source by swimming away or diving (Richardson, 1995; Nowacek, 2007; Southall et al., 2007). Of the Level B takes, 150 bottlenose dolphin; 2,584 pantropical spotted dolphin; 612 striped dolphin; 119 spinner dolphin; 377 rough toothed dolphin; 493 Fraser’s dolphin; and 84 Risso’s dolphin takes are predicted to be in the form of generally mild TTS from sonar and other active acoustic sources. Though the group size and behavior of these species makes it likely that Navy lookouts would detect them and implement shutdown if appropriate, the proposed mitigation has a provision that allows the Navy to continue operation of MFAS if the animals are clearly bowriding even after the Navy has initially maneuvered to try and avoid closing with the animals. As mentioned above, many of the recorded dolphin vocalizations overlap with the MFAS/ HFAS TTS frequency range (2–20 kHz), however, as noted above, NMFS does not anticipate TTS of a serious degree or extended duration to occur. Recovery from a threshold shift (TTS) can take a few minutes to a few days, depending on the exposure duration, sound exposure level, and the magnitude of the initial shift, with larger threshold shifts and longer exposure durations requiring longer recovery times (Finneran et al., 2005; Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney et al., 2009b). However, large threshold shifts are not anticipated for these activities because of the unlikelihood that animals will remain within the ensonified area (due to the short duration of the majority of exercises, the speed of the vessels, and the short distance within which the animal would need to approach the sound source) at high levels for the duration necessary to induce larger threshold shifts. Threshold shifts do not necessarily affect all hearing frequencies equally, so some threshold shifts may VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 not interfere with an animal’s hearing of biologically relevant sounds. One Level B take each for Fraser’s dolphin and pantropical spotted dolphin is predicted to be in the form of non-injurious TTS from impulsive sound sources (explosive detonations). Research and observations suggest that if delphinids are exposed to impulse sound sources, they may react by alerting, ignoring the stimulus, changing their behavior or vocalizations, or avoiding the area by swimming away or diving (Richardson, 1995; Finneran, 2002; Madsen et al., 2006; Weir, 2008; and Miller et al., 2009). Although NMFS has designated Pacific stocks for bottlenose, pantropical spotted, striped, spinner, rough toothed, Fraser’s, and Risso’s dolphins (Carretta et al., 2014), little is known about the stock structure for these species in the MITT Study Area and NMFS currently has not designated any stocks for these species specific to the MITT Study Area. The MITT activities are not expected to occur in an area/time of specific importance for reproductive, feeding, or other known critical behaviors for dolphins. Consequently, the activities are not expected to adversely impact rates of recruitment or survival of these species. Long-Term Consequences The best assessment of long-term consequences from training and testing activities will be to monitor the populations over time within a given Navy range complex. A U.S. workshop on Marine Mammals and Sound (Fitch et al., 2011) indicated a critical need for baseline biological data on marine mammal abundance, distribution, habitat, and behavior over sufficient time and space to evaluate impacts from human-generated activities on long-term population survival. The Navy has developed monitoring plans for protected marine mammals occurring on Navy ranges with the goal of assessing the impacts of training and testing activities on marine species and the effectiveness of the Navy’s current mitigation practices. Continued monitoring efforts over time will be necessary to completely evaluate the long-term consequences of exposure to noise sources. Since 2006 across all Navy range complexes (in the Atlantic, Gulf of Mexico, and the Pacific), there have been more than 80 reports; Major Exercise Reports, Annual Exercise Reports, and Monitoring Reports. For the Pacific since 2011, there have been 29 monitoring and exercise reports submitted to NMFS to further research goals aimed at understanding the Navy’s PO 00000 Frm 00051 Fmt 4701 Sfmt 4700 46161 impact on the environment as it carries out its mission to train and test (www. navymarinespeciesmonitoring.us). In addition to this multi-year record of reports from across the Navy, there have also been ongoing Behavioral Response Study research efforts (in Southern California and the Bahamas) specifically focused on determining the potential effects from Navy midfrequency sonar (Southall et al., 2011, 2012; Tyack et al., 2011; DeRuiter et al., 2013b; Goldbogen et al., 2013; Moretti et al., 2014). This multi-year compendium of monitoring, observation, study, and broad scientific research is informative with regard to assessing the effects of Navy training and testing in general. Given that this record involves many of the same Navy training and testing activities being considered for the Study Area and because it includes all the marine mammal taxonomic families and many of the same species, this compendium of Navy reporting is directly applicable to assessing locations such as the Mariana Islands. In the Hawaii and Southern California Navy training and testing ranges from 2009 to 2012, Navy-funded marine mammal monitoring research completed over 5,000 hours of visual survey effort covering over 65,000 nautical miles, sighted over 256,000 individual marine mammals, took over 45,600 digital photos and 36 hours of digital video, attached 70 satellite tracking tags to individual marine mammals, and collected over 40,000 hours of passive acoustic recordings. In Hawaii alone between 2006 and 2012, there were 21 scientific marine mammal surveys conducted before, during, or after major exercises. Based on monitoring conducted before, during, and after Navy training and testing events since 2006, the NMFS’ assessment is that it is unlikely there will be impacts having any longterm consequences to populations of marine mammals as a result of the proposed continuation of training and testing in the ocean areas historically used by the Navy including the MITT Study Area. This assessment of likelihood is based on four indicators from areas in the Pacific where Navy training and testing has been ongoing for decades: (1) Evidence suggesting or documenting increases in the numbers of marine mammals present (Calambokidis and Barlow, 2004; Falcone et al., 2009; Hildebrand and McDonald, 2009; Falcone and Shorr, 2012; Calambokidis et al., 2009a; Berman-Kowalewski et al., 2010; Moore and Barlow, 2011; Barlow et al. 2011; Kerosky et al,. 2012; Smultea et al., 2013), or evidence suggesting E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46162 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations populations have reached carrying capacity (Monnahan et al., 2014), (2) examples of documented presence and site fidelity of species and long-term residence by individual animals of some species (Hooker et al., 2002; McSweeney et al., 2007; McSweeney et al., 2009; McSweeney et al., 2010; Martin and Kok, 2011; BaumannPickering et al., 2012; Falcone and Schorr, 2014), (3) use of training and testing areas for breeding and nursing activities (Littnan, 2010), and (4) eight years of comprehensive monitoring data indicating a lack of any observable effects to marine mammal populations as a result of Navy training and testing activities. To summarize, while the evidence covers most marine mammal taxonomic suborders, it is limited to a few species and only suggestive of the general viability of those species in intensively used Navy training and testing areas (Barlow et al., 2011; Calambokidis et al., 2009b; Falcone et al., 2009; Littnan, 2011; Martin and Kok, 2011; McCarthy et al., 2011; McSweeney et al., 2007; McSweeney et al., 2009; Moore and Barlow, 2011; Tyack et al., 2011; Southall et al., 2012a; Melcon, 2012; Goldbogen, 2013; Baird et al., 2013). However, there is no direct evidence that routine Navy training and testing spanning decades has negatively impacted marine mammal populations at any Navy range complex. Although there have been a few strandings associated with use of sonar in other locations (see U.S. Department of the Navy, 2013b), Ketten (2012) has recently summarized, ‘‘to date, there has been no demonstrable evidence of acute, traumatic, disruptive, or profound auditory damage in any marine mammal as the result of anthropogenic noise exposures, including sonar.’’ Therefore, based on the best available science (McSweeney et al., 2007; Falcone et al., 2009; McSweeney et al., 2009; Littnan, 2010; Barlow et al., 2011; Martin and Kok, 2011; McCarthy et al., 2011; Moore and Barlow, 2011; Tyack et al., 2011; Southall et al., 2012a; Manzano-Roth et al., 2013; DeRuiter et al., 2013; Goldbogen et al., 2013; Moretti et al., 2014; Smultea and Jefferson, 2014), including data developed in the series of reports submitted to NMFS, we believe that long-term consequences for individuals or populations are unlikely to result from Navy training and testing activities in the Study Area. Final Determination NMFS concludes that training and testing activities proposed in the MITT Study Area could result in Level B and Level A takes, as summarized in Table VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 11. Based on best available science NMFS concludes that exposures to marine mammal species due to MITT activities would result in primarily short-term (temporary and short in duration) and relatively infrequent effects to most individuals, and not of the type or severity that would be expected to be additive for the portion of the stocks and species likely to be exposed. Marine mammal takes from Navy activities are not expected to impact annual rates of recruitment or survival and will therefore not result in population-level impacts for the following reasons: • Most acoustic harassments (greater than 99 percent) are within the noninjurious TTS or behavioral effects zones (Level B harassment consisting of generally temporary modifications in behavior) and none of the estimated exposures result in mortality. • As mentioned earlier, an animal’s exposure to a higher received level is more likely to result in a behavioral response that is more likely to adversely affect the health of the animal. For low frequency cetaceans (mysticetes) in the Study Area, most Level B exposures will occur at received levels less than 156 dB (Table 22). The majority of estimated odontocete takes from MFAS/HFAS (at least for hull-mounted sonar, which is responsible for most of the sonar-related takes) also result from exposures to received levels less than 156 dB (Table 22). Therefore, the majority of Level B takes are expected to be in the form of milder responses (i.e., lower-level exposures that still rise to the level of a take, but would likely be less severe in the range of responses that qualify as a take) and are not expected to have deleterious impacts on the fitness of any individuals. • Acoustic disturbances caused by Navy sonar and explosives are shortterm, intermittent, and (in the case of sonar) transitory, even during major training exercises. Navy activities are generally unit level. Unit level events occur over a small spatial scale (one to a few 10s of square miles) and with few participants (usually one or two). Single-unit unit level training would typically involve a few hours of sonar use, with a typical nominal ping of every 50 seconds (duty cycle). Even though an animal’s exposure to active sonar may be more than one time, the intermittent nature of the sonar signal, its low duty cycle, and the fact that both the vessel and animal are moving provide a very small chance that exposure to active sonar for individual animals and stocks would be repeated over extended periods of time. Consequently, we would not expect the PO 00000 Frm 00052 Fmt 4701 Sfmt 4700 Navy’s activities to create conditions of long-term, continuous underwater noise leading to habitat abandonment or longterm hormonal or physiological stress responses in marine mammals. • Years of monitoring of Navy activities (since 2006) have documented hundreds of thousands of marine mammals on the range complexes and there are only two instances of overt behavioral change that have been observed. • Years of monitoring of Navy activities have documented no instances of injury to marine mammals as a direct result of non-impulse acoustic sources. • In at least three decades of similar activities, only one instance of injury to marine mammals (March 2011; three long-beaked common dolphin off Southern California) has been documented as a result of training or testing using an impulse source (underwater explosion). • Range complexes where intensive training and testing have been occurring for decades have populations of multiple species with strong site fidelity (including highly sensitive resident beaked whales at some locations) and increases in the number of some species. Populations of beaked whales and other odontocetes in the Bahamas, and other Navy fixed ranges that have been operating for tens of years, appear to be stable. Based on the analysis contained herein of the likely effects of the specified activity on marine mammals and their habitat, which includes consideration of the materials provided in the Navy’s LOA application and MITT FEIS/OEIS, and dependent upon the implementation of the mitigation and monitoring measures, NMFS finds that the total marine mammal take from the Navy’s training and testing activities in the MITT Study Area will have a negligible impact on the affected marine mammal species or stocks. NMFS has issued regulations for these activities that prescribe the means of effecting the least practicable adverse impact on marine mammal species or stocks and their habitat and set forth requirements pertaining to the monitoring and reporting of that taking. Impact on Availability of Affected Species for Taking for Subsistence Uses NMFS has determined that the issuance of regulations and subsequent LOA for Navy training and testing activities in the MITT Study Area would not have an unmitigable adverse impact on the availability of species or stocks for subsistence use, since there are no such uses in the specified area. E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations Endangered Species Act (ESA) There are five marine mammal species under NMFS’ jurisdiction that are listed as endangered or threatened under the ESA with confirmed or possible occurrence in the Study Area: Blue whale, humpback whale, fin whale, sei whale, and sperm whale. The Navy consulted with NMFS pursuant to section 7 of the ESA, and NMFS also consulted internally on the issuance of an LOA under section 101(a)(5)(A) of the MMPA for MITT activities. NMFS issued a Biological Opinion concluding that the issuance of the rule and subsequent LOA are likely to adversely affect, but are not likely to jeopardize, the continued existence of the threatened and endangered species (and species proposed for listing) under NMFS’ jurisdiction and are not likely to result in the destruction or adverse modification of critical habitat in the MITT Study Area. The Biological Opinion for this action is available on NMFS’ Web site (https:// www.nmfs.noaa.gov/pr/permits/ incidental/). National Environmental Policy Act (NEPA) NMFS participated as a cooperating agency on the MITT FEIS/OEIS, which was published on May 22, 2015 and is available on the Navy’s Web site: https://www.mitt-eis.com. NMFS determined that the MITT FEIS/OEIS is adequate and appropriate to meet our responsibilities under NEPA for the issuance of regulations and LOA and adopted the Navy’s MITT FEIS/OEIS. mstockstill on DSK4VPTVN1PROD with RULES2 Classification The Office of Management and Budget has determined that this 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 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 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 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 LOA 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 the action would not result in a significant economic impact on a substantial number of small entities. The Assistant Administrator for Fisheries has determined that there is good cause under the Administrative Procedure Act (5 U.S.C 553(d)(3)) to waive the 30-day delay in the effective date of the measures contained in the final rule. The Navy is the only entity subject to the regulations, and it has informed NMFS that it requests that this final rule take effect by August 3, 2015, when the regulations issued by NMFS to govern the unintentional taking of marine mammals incidental to the Navy’s activities in the MIRC study area from 2010 to 2015 expire. Any delay of enacting the final rule would result in either: (1) A suspension of planned naval training, which would disrupt vital training essential to national security; or (2) the Navy’s procedural non-compliance with the MMPA (should the Navy conduct training without an LOA), thereby resulting in the potential for unauthorized takes of marine mammals. Moreover, the Navy is ready to implement the rule immediately. For these reasons, the Assistant Administrator finds good cause to waive the 30-day delay in the effective date. 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: July 24, 2015. Paul N. Doremus, Deputy Assistant Administrator for Operations, National Marine Fisheries Service. For reasons set forth in the preamble, 50 CFR part 218 is 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 follow: ■ PO 00000 Frm 00053 Fmt 4701 Sfmt 4700 46163 Authority: 16 U.S.C. 1361 et seq. 2. Subpart J is added to part 218 to read as follows: ■ Subpart J—Taking and Importing Marine Mammals; U.S. Navy’s Mariana Islands Training and Testing (MITT) Sec. 218.90 Specified activity and specified geographical region. 218.91 Effective dates and definitions. 218.92 Permissible methods of taking. 218.93 Prohibitions. 218.94 Mitigation. 218.95 Requirements for monitoring and reporting. 218.96 Applications for Letters of Authorization. 218.97 Letter of Authorization. 218.98 Renewal and modifications of Letters of Authorization. Subpart J—Taking and Importing Marine Mammals; U.S. Navy’s Mariana Islands Training and Testing (MITT) § 218.90 Specified activity and specified geographical region. (a) Regulations in this subpart apply only to the U.S. Navy for the taking of marine mammals that occurs in the area outlined in paragraph (b) of this section and that occurs incidental to the activities described in paragraph (c) of this section. (b) The taking of marine mammals by the Navy is only authorized if it occurs within the MITT Study Area, which includes the Mariana Islands Range Complex (MIRC) and areas to the north and west. The Study Area includes established ranges, operating areas, warning areas, and special use airspace in the region of the Mariana Islands that are part of the MIRC, its surrounding seas, and a transit corridor to the Hawaii Range Complex. The Study Area also includes Navy pierside locations where sonar maintenance and testing may occur. (c) The taking of marine mammals by the Navy is only authorized if it occurs incidental to the following activities within the designated amounts of use: (1) Non-impulsive Sources Used During Training and Testing: (i) Low-frequency (LF) Source Classes: (A) LF4—an average of 123 hours per year. (B) LF5—an average of 11 hours per year. (C) LF6—an average of 40 hours per year. (ii) Mid-frequency (MF) Source Classes: (A) MF1—an average of 1,872 hours per year. (B) MF2—an average of 625 hours per year. (C) MF3—an average of 192 hours per year. E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46164 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations (D) MF4—an average of 214 hours per year. (E) MF5—an average of 2,588 items per year. (F) MF6—an average of 33 items per year. (G) MF8—an average of 123 hours per year. (H) MF9—an average of 47 hours per year. (I) MF10—an average of 231 hours per year. (J) MF11—an average of 324 hours per year. (K) MF12—an average of 656 hours per year. (iii) High-frequency (HF) and Very High-frequency (VHF) Source Classes: (A) HF1—an average of 113 hours per year. (B) HF4—an average of 1,060 hours per year. (C) HF5—an average of 336 hours per year. (D) HF6—an average of 1,173 hours per year. (iv) Anti-Submarine Warfare (ASW) Source Classes: (A) ASW1—an average of 144 hours per year. (B) ASW2—an average of 660 items per year. (C) ASW3—an average of 3,935 hours per year. (D) ASW4—an average of 32 items per year. (v) Torpedoes (TORP) Source Classes: (A) TORP1—an average of 115 items per year. (B) TORP2—an average of 62 items per year. (vi) Acoustic Modems (M): (A) M3—an average of 112 hours per year. (B) [Reserved] (vii) Swimmer Detection Sonar (SD): (A) SD1—an average 2,341 hours per year. (B) [Reserved] (2) Impulsive Source Detonations During Training and Testing: (i) Explosive Classes: (A) E1 (0.1 to 0.25 lb NEW)—an average of 10,140 detonations per year. (B) E2 (0.26 to 0.5 lb NEW)—an average of 106 detonations per year. (C) E3 (>0.5 to 2.5 lb NEW)—an average of 932 detonations per year. (D) E4 (>2.5 to 5 lb NEW)—an average of 420 detonations per year. (E) E5 (>5 to 10 lb NEW)—an average of 684 detonations per year. (F) E6 (>10 to 20 lb NEW)—an average of 76 detonations per year. (G) E8 (>60 to 100 lb NEW)—an average of 16 detonations per year. (H) E9 (>100 to 250 lb NEW)—an average of 4 detonations per year. (I) E10 (>250 to 500 lb NEW)—an average of 12 detonations per year. VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 (J) E11 (>500 to 650 lb NEW)—an average of 6 detonations per year. (K) E12 (>650 to 2,000 lb NEW)—an average of 184 detonations per year. (ii) [Reserved] § 218.91 Effective dates and definitions. (a) Regulations in this subpart are effective August 3, 2015 through August 3, 2020. (b) The following definitions are utilized in these regulations: (1) Uncommon Stranding Event (USE)—A stranding event that takes place within an OPAREA where a Major Training Exercise (MTE) occurs and involves any one of the following: (i) Two or more individuals of any cetacean species (not including mother/ calf pairs, unless of species of concern listed in paragraph (b)(1)(ii) of this section) found dead or live on shore within a 2-day period and occurring within 30 miles of one another. (ii) A single individual or mother/calf pair of any of the following marine mammal species of concern: Beaked whale of any species, Kogia spp., Risso’s dolphin, melon-headed whale, pilot whale, humpback whale, sperm whale, blue whale, fin whale, or sei whale. (iii) A group of two or more cetaceans of any species exhibiting indicators of distress. (2) Shutdown—The cessation of active sonar operation or detonation of explosives within 14 nautical miles of any live, in the water, animal involved in a USE. § 218.92 Permissible methods of taking. (a) Under a Letter of Authorization (LOA) issued pursuant to § 218.97, the Holder of the Letter of Authorization may incidentally, but not intentionally, take marine mammals within the area described in § 218.90, provided the activity is in compliance with all terms, conditions, and requirements of these regulations and the appropriate LOA. (b) The activities identified in § 218.90(c) must be conducted in a manner that minimizes, to the greatest extent practicable, any adverse impacts on marine mammals and their habitat. (c) The incidental take of marine mammals under the activities identified in § 218.90(c) is limited to the following species, by the identified method of take: (1) Level B Harassment for all Training and Testing Activities: (i) Mysticetes: (A) Blue whale (Balaenoptera musculus)—140 (an average of 28 annually) (B) Bryde’s whale (Balaenoptera edeni)—1,990 (an average of 398 annually) PO 00000 Frm 00054 Fmt 4701 Sfmt 4700 (C) Fin whale (Balaenoptera physalus)—140 (an average of 28 annually) (D) Humpback whale (Megaptera novaeangliae)—4,300 (an average of 860 annually) (E) Minke whale (Balaenoptera acutorostrata)—505 (an average of 101 annually) (F) Sei whale (Balaenoptera borealis)—1,595 (an average of 319 annually) (G) Omura’s whale (Balaenoptera omurai)—515 (an average of 103 annually) (ii) Odontocetes: (A) Blainville’s beaked whale (Mesoplodon densirostris)—22,130 (an average of 4,426 annually) (B) Bottlenose dolphin (Tursiops truncatus)—3,705 (an average of 741 annually) (C) Cuvier’s beaked whale (Ziphius cavirostris)—112,705 (an average of 22,541 annually) (D) Dwarf sperm whale (Kogia sima)— 71,085 (an average of 14,217 annually) (E) False killer whale (Pseudorca crassidens)—2,775 (an average of 555 annually) (F) Fraser’s dolphin (Lagenodelphis hosei)—12,860 (an average of 2,572 annually) (G) Gingko-toothed beaked whale (Mesoplodon ginkgodens)—19,485 (an average of 3,897 annually) (H) Killer whale (Orcinus orca)—420 (an average of 84 annually) (I) Longman’s beaked whale (Indopacetus pacificus)—9,620 (an average of 1,924 annually) (J) Melon-headed whale (Peponocephala electra)—10,425 (an average of 2,085 annually) (K) Pantropical spotted dolphin (Stenella attenuata)—64,055 (an average of 12,811 annually) (L) Pygmy killer whale (Feresa attenuata)—525 (an average of 105 annually) (M) Pygmy sperm whale (Kogia breviceps)—27,895 (an average of 5,579 annually) (N) Risso’s dolphin (Grampus griseus)—2,525 (an average of 505 annually) (O) Rough-toothed dolphin (Steno bredanensis)—9,095 (an average of 1,819 annually) (P) Short-finned pilot whale (Globicephala macrorhynchus)—9,075 (an average of 1,815 annually) (Q) Sperm whale (Physeter macrocephalus)—2,530 (an average of 506 annually) (R) Spinner dolphin (Stenella longirostris)—2,945 (an average of 589 annually) E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations (S) Striped dolphin (Stenella coerulealba)—16,490 (an average of 3,298 annually) (2) Level A Harassment for all Training and Testing Activities: (i) Odontocetes: (A) Dwarf sperm whale (Kogia sima)— 205 (an average of 41 annually) (B) Pygmy sperm whale (Kogia breviceps)—75 (an average of 15 annually) (ii) [Reserved] § 218.93 Prohibitions. Notwithstanding takings contemplated in § 218.92 and authorized by an LOA issued under §§ 216.106 and 218.97 of this chapter, no person in connection with the activities described in § 218.90 may: (a) Take any marine mammal not specified in § 218.92(c); (b) Take any marine mammal specified in § 218.92(c) other than by incidental take as specified in § 218.92(c); (c) Take a marine mammal specified in § 218.92(c) if such taking results in more than a negligible impact on the species or stocks of such marine mammal; or (d) Violate, or fail to comply with, the terms, conditions, and requirements of these regulations or an LOA issued under §§ 216.106 and 218.97. mstockstill on DSK4VPTVN1PROD with RULES2 § 218.94 Mitigation. (a) When conducting training and testing activities, as identified in § 218.90, the mitigation measures contained in the LOA issued under §§ 216.106 and 218.97 of this chapter must be implemented. These mitigation measures include, but are not limited to: (1) Lookouts. The following are protective measures concerning the use of lookouts. (i) Lookouts positioned on surface ships will be dedicated solely to diligent observation of the air and surface of the water. Their observation objectives will include, but are not limited to, detecting the presence of biological resources and recreational or fishing boats, observing mitigation zones, and monitoring for vessel and personnel safety concerns. (ii) Lookouts positioned in aircraft or on boats will, to the maximum extent practicable and consistent with aircraft and boat safety and training and testing requirements, comply with the observation objectives described in paragraph (a)(1)(i) of this section. (iii) Lookout measures for nonimpulse sound: (A) With the exception of vessels less than 65 ft (20 m) in length and ships that are minimally manned, ships using low-frequency or hull-mounted mid- VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 frequency active sonar sources associated with anti-submarine warfare and mine warfare activities at sea will have two lookouts at the forward position. For the purposes of this rule, low-frequency active sonar does not include surface towed array surveillance system low-frequency active sonar. (B) While using low-frequency or hull-mounted mid-frequency active sonar sources associated with antisubmarine warfare and mine warfare activities at sea, ships less than 65 ft (20 m) in length and ships that are minimally manned will have one lookout at the forward position of the vessel due to space and manning restrictions. (C) Ships conducting active sonar activities while moored or at anchor (including pierside testing or maintenance) will maintain one lookout. (D) Surface ships or aircraft conducting high-frequency or non-hull mounted mid-frequency active sonar activities associated with antisubmarine warfare and mine warfare activities at sea will have one lookout. (iv) Lookout measures for explosives and impulse sound: (A) Aircraft conducting IEER sonobuoy activities and explosive sonobuoy exercises will have one lookout. (B) Surface vessels conducting antiswimmer grenade activities will have one lookout. (C) During general mine countermeasure and neutralization activities using up to a 20-lb net explosive weight detonation (bin E6 and below), vessels greater than 200 ft (61 m) will have two lookouts, while vessels less than 200 ft (61 m) or aircraft will have one lookout. (D) Mine neutralization activities involving positive control diver-placed charges using up to a 20-lb net explosive weight detonation will have two lookouts. The divers placing the charges on mines will report all marine mammal sightings to their supporting small boat or Range Safety Officer. (E) When mine neutralization activities using diver-placed charges with up to a 20-lb net explosive weight detonation are conducted with a timedelay firing device, four lookouts will be used. Two lookouts will be positioned in each of two small rigid hull inflatable boats. When aircraft are used, the pilot or member of the aircrew will serve as an additional lookout. The divers placing the charges on mines will report all marine mammal sightings to their supporting small boat or Range Safety Officer. PO 00000 Frm 00055 Fmt 4701 Sfmt 4700 46165 (F) Surface vessels or aircraft conducting small- or medium-caliber gunnery exercises against a surface target will have one lookout. (G) Aircraft conducting missile exercises (including rockets) against surface targets will have one lookout. (H) Aircraft conducting bombing exercises will have one lookout. (I) During explosive torpedo testing, one lookout will be used and positioned in an aircraft. (J) During sinking exercises, two lookouts will be used. One lookout will be positioned in an aircraft and one on a surface vessel. (K) Surface vessels conducting explosive and non-explosive largecaliber gunnery exercises will have one lookout. (v) Lookout measures for physical strike and disturbance: (A) While underway, surface ships will have at least one lookout. (B) During activities using towed inwater devices, that are towed from a manned platform, one lookout will be used. (C) Non-explosive small-, medium-, and large-caliber gunnery exercises using a surface target will have one lookout. (D) Non-explosive bombing exercises will have one lookout. (2) Mitigation zones. The following are protective measures concerning the implementation of mitigation zones. (i) Mitigation zones will be measured as the radius from a source and represent a distance to be monitored. (ii) Visual detections of marine mammals within a mitigation zone will be communicated immediately to a watch station for information dissemination and appropriate action. (iii) Mitigation zones for non-impulse sound: (A) When marine mammals are visually detected, the Navy shall ensure that low-frequency and hull-mounted mid-frequency active sonar transmission levels are limited to at least 6 dB below normal operating levels (for sources that can be powered down during the activity) if any visually detected marine mammals are within 1,000 yd (914 m) of the source (i.e., the bow). (B) The Navy shall ensure that lowfrequency and hull-mounted midfrequency active sonar transmissions are limited to at least 10 dB below the equipment’s normal operating level (for sources that can be powered down during the activity) if any detected marine mammals are sighted within 500 yd (457 m) of the source. (C) The Navy shall ensure that lowfrequency and hull-mounted midfrequency active sonar transmissions E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46166 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations (for sources that can be turned off during the activity) are ceased if any visually detected marine mammals are within 200 yd (183 m) of the sonar dome. Active transmission will recommence if any one of the following conditions is 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 and speed and the relative motion between the animal and the source; the mitigation zone has been clear from any additional sightings for a period of 30 minutes; the ship has transited more than 2,000 yd. (1.8 kilometers [km]) beyond the location of the last sighting; or the ship concludes that dolphins are deliberately closing in on the ship to ride the ship’s bow wave (and there are no other marine mammal sightings within the mitigation zone). (D) If the source is not able to be powered down during the activity (e.g., low-frequency sources within bins LF4 and LF5), mitigation will involve ceasing active transmission if a marine mammal is sighted within 200 yd. (183 m). Active transmission will recommence if any one of the following conditions is 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 and speed and the relative motion between the animal and the source; the mitigation zone has been clear from any additional sightings for a period of 30 minutes; or the ship has transited more than 400 yd. (366 m) beyond the location of the last sighting. (E) With the exception of activities involving platforms operating at high altitudes, when marine mammals are visually detected, the Navy shall ensure that high-frequency and non-hullmounted mid-frequency active sonar transmission (for sources that can be turned off during the activity) is ceased if any visually detected marine mammals are within 200 yd (183 m) of the source. Active transmission will recommence if any one of the following conditions is 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 and speed and the relative motion between the animal and the source, the mitigation zone has been clear from any additional sightings for a period of 10 minutes for an aircraft-deployed source, the mitigation zone has been clear from any additional sightings for a period of 30 VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 minutes for a vessel-deployed source, the vessel or aircraft has repositioned itself more than 400 yd. (366 m) away from the location of the last sighting, or the vessel concludes that dolphins are deliberately closing in to ride the vessel’s bow wave (and there are no other marine mammal sightings within the mitigation zone). (F) Prior to start up or restart of active sonar, operators shall check that the mitigation zone radius around the sound source is clear of marine mammals. (G) Generally, the Navy shall operate sonar at the lowest practicable level, not to exceed 235 dB, except as required to meet tactical training objectives. (iv) Mitigation zones for explosive and impulse sound: (A)(1) A mitigation zone with a radius of 600 yd (549 m) shall be established for IEER sonobuoys (bin E4). Mitigation would include pre-exercise aerial observation and passive acoustic monitoring, which would begin 30 minutes before the first source/receiver pair detonation and continue throughout the duration of the exercise. The pre-exercise aerial observation would include the time it takes to deploy the sonobuoy pattern (deployment is conducted by aircraft dropping sonobuoys in the water). Explosive detonations would cease if a marine mammal is sighted within the mitigation zone. Detonations would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 30 minutes. (2) Passive acoustic monitoring would be conducted with Navy assets, such as sonobuoys, already participating in the activity. These assets would only detect vocalizing marine mammals within the frequency bands monitored by Navy personnel. Passive acoustic detections would not provide range or bearing to detected animals, and therefore cannot provide locations of these animals. Passive acoustic detections would be reported to lookouts posted in aircraft and on vessels in order to increase vigilance of their visual observation. (B)(1) A mitigation zone with a radius of 350 yd (320 m) shall be established for explosive sonobuoys using 0.5–2.5 lb net explosive weight (bin E3). Mitigation would include pre-exercise aerial monitoring during deployment of the field of sonobuoy pairs (typically up PO 00000 Frm 00056 Fmt 4701 Sfmt 4700 to 20 minutes) and continuing throughout the duration of the exercise within a mitigation zone of 350 yd (320 m) around an explosive sonobuoy. Explosive detonations would cease if a marine mammal is sighted within the mitigation zone. Detonations would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 10 minutes. (2) Passive acoustic monitoring would also be conducted with Navy assets, such as sonobuoys, already participating in the activity. These assets would only detect vocalizing marine mammals within the frequency bands monitored by Navy personnel. Passive acoustic detections would not provide range or bearing to detected animals, and therefore cannot provide locations of these animals. Passive acoustic detections would be reported to lookouts posted in aircraft in order to increase vigilance of their visual observation. (C) A mitigation zone with a radius of 200 yd (183 m) shall be established for anti-swimmer grenades (bin E2). Mitigation would include visual observation from a small boat immediately before and during the exercise within a mitigation zone of 200 yd (183 m) around an anti-swimmer grenade. Explosive detonations would cease if a marine mammal is sighted within the mitigation zone. Detonations would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, the mitigation zone has been clear from any additional sightings for a period of 30 minutes, or the activity has been repositioned more than 400 yd (366 m) away from the location of the last sighting. (D) A mitigation zone ranging from 350 yd (320 m) to 800 yd (732 m), dependent on charge size and if the activity involves the use of diver-placed charges, shall be established for mine countermeasure and neutralization activities using positive control firing devices. Mitigation zone distances are specified for charge size in the following table. E:\FR\FM\03AUR2.SGM 03AUR2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations Charge size net explosive weight (bins) 2.5–5 lb. (1.2–2.3 kg) (E4) ........................ 5–10 lb. (2.7–4.5 kg) (E5) ........................ >10–20 lb. (5–9.1 kg) (E6) ........................ General mine countermeasure and neutralization activities using positive control firing devices 1 Predicted average range to TTS Predicted average range to PTS Predicted maximum range to PTS 434 yd (474 m) 197 yd (180 m) 563 yd (515 m) 525 yd (480 m) 204 yd (187 m) 766 yd (700 m) 288 yd (263 m) 46167 Mine countermeasure and neutralization activities using diver placed charges under positive control 2 Predicted average range to TTS Predicted average range to PTS Predicted maximum range to PTS 600 yd (549 m) 545 yd (498 m) 169 yd (155 m) 301 yd (275 m) 350 yd. (320 m). 649 yd (593 m) 800 yd (732 m) 587 yd (537 m) 203 yd (185 m) 464 yd (424 m) 500 yd. (457 m). 648 yd (593 m) 800 yd (732 m) 647 yd (592 m) 232 yd (212 m) 469 yd (429 m) 500 yd. (457 m). Recommended mitigation zone Recommended mitigation zone mstockstill on DSK4VPTVN1PROD with RULES2 PTS: permanent threshold shift; TTS: temporary threshold shift. 1 These mitigation zones are applicable to all mine countermeasure and neutralization activities conducted in all locations specified in Chapter 2 of the Navy’s LOA application. 2 These mitigation zones are only applicable to mine countermeasure and neutralization activities involving the use of diver placed charges. These activities are conducted in shallow-water and the mitigation zones are based only on the functional hearing groups with species that occur in these areas (mid-frequency cetaceans and sea turtles). (1) During general mine countermeasure and neutralization activities, mitigation would include visual observation from one or more small boats or aircraft beginning 30 minutes before, during, and 30 minutes after (when helicopters are not involved in the activity) or 10 minutes before, during, and 10 minutes after (when helicopters are involved in the activity) the completion of the exercise within the mitigation zones around the detonation site. (2) For activities involving diverplaced charges, visual observation would be conducted by either two small boats, or one small boat in combination with one helicopter. Boats would position themselves near the mid-point of the mitigation zone radius (but always outside the detonation plume radius and human safety zone) and travel in a circular pattern around the detonation location. When using two boats, each boat would be positioned on opposite sides of the detonation location, separated by 180 degrees. If used, helicopters would travel in a circular pattern around the detonation location. (3) For both general and diver-placed positive control mine countermeasure and neutralization activities, explosive detonations will cease if a marine mammal is sighted within the mitigation zone. Detonations will recommence if any one of the following conditions is 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 and speed and the relative motion between the animal and the source, the mitigation zone has been clear from any additional sightings for a period of 30 minutes, when helicopters are not involved in the activity or the mitigation zone has been clear from any additional sightings for a VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 period of 10 minutes when helicopters are involved in the activity. (E) A mitigation zone with a radius of 1,000 yd (914 m) shall be established for mine countermeasure and neutralization activities using diver-placed time-delay firing devices (bin E6). Mine neutralization activities involving diverplaced charges would not include timedelay longer than 10 minutes. Mitigation would include visual observation from small boats or aircraft commencing 30 minutes before, during, and until 30 minutes after the completion of the exercise within a mitigation zone of 1,000 yd (914 m) around the detonation site. During activities using time-delay firing devices involving up to a 20 lb net explosive weight charge, visual observation will take place using two small boats. Fuse initiation would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 30 minutes. (1) Survey boats would position themselves near the mid-point of the mitigation zone radius (but always outside the detonation plume radius/ human safety zone) and travel in a circular pattern around the detonation location. One lookout from each boat would look inward toward the detonation site and the other lookout would look outward away from the detonation site. When using two small boats, each boat would be positioned on opposite sides of the detonation location, separated by 180 degrees. If available for use, helicopters would travel in a circular pattern around the detonation location. (2) [Reserved] PO 00000 Frm 00057 Fmt 4701 Sfmt 4700 (F) A mitigation zone with a radius of 200 yd (183 m) shall be established for small- and medium-caliber gunnery exercises with a surface target (bin E2). Mitigation would include visual observation from a vessel or aircraft immediately before and during the exercise within a mitigation zone of 200 yd (183 m) around the intended impact location. Vessels would observe the mitigation zone from the firing position. When aircraft are firing, the aircrew would maintain visual watch of the mitigation zone during the activity. Firing would cease if a marine mammal is sighted within the mitigation zone. Firing would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, the mitigation zone has been clear from any additional sightings for a period of 10 minutes for a firing aircraft, the mitigation zone has been clear from any additional sightings for a period of 30 minutes for a firing vessel, or the intended target location has been repositioned more than 400 yd (366 m) away from the location of the last sighting. (G) A mitigation zone with a radius of 600 yd (549 m) shall be established for large-caliber gunnery exercises with a surface target (bin E5). Mitigation would include visual observation from a ship immediately before and during the exercise within a mitigation zone of 600 yd (549 m) around the intended impact location. Ships would observe the mitigation zone from the firing position. Firing would cease if a marine mammal is sighted within the mitigation zone. Firing would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46168 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 30 minutes. (H) A mitigation zone with a radius of 900 yd (823 m) around the deployed target shall be established for missile exercises involving aircraft firing up to 250 lb net explosive weight using and a surface target (bin E9). When aircraft are firing, mitigation would include visual observation by the aircrew or supporting aircraft prior to commencement of the activity within a mitigation zone of 900 yd (823 m) around the deployed target. Firing would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 10 minutes or 30 minutes (depending on aircraft type). (I) A mitigation zone with a radius of 2,000 yd (1.8 km) shall be established for missile exercises involving aircraft firing >250 to 500 lb net explosive weight using and a surface target (bin E10). When aircraft are firing, mitigation would include visual observation by the aircrew prior to commencement of the activity within a mitigation zone of 2,000 yd (1.8 km) around the intended impact location. Firing would cease if a marine mammal is sighted within the mitigation zone. Firing would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 10 minutes or 30 minutes (depending on aircraft type). (J) A mitigation zone with a radius of 2,500 yd (2.3 km) shall be established for bombing exercises (bin E12). Mitigation would include visual observation from the aircraft immediately before the exercise and during target approach within a mitigation zone of 2,500 yd (2.3 km) around the intended impact location. Bombing would cease if a marine mammal is sighted within the mitigation zone. Bombing would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 10 minutes. (K)(1) A mitigation zone with a radius of 2,100 yd (1.9 km) shall be established for torpedo (explosive) testing (except for aircraft operating at high altitudes) (bin E11). Mitigation would include visual observation by aircraft immediately before, during, and after the exercise within a mitigation zone of 2,100 yd (1.9 km) around the intended impact location. Firing would cease if a marine mammal is sighted within the mitigation zone. Firing would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 10 minutes or 30 minutes (depending on aircraft type). (2) In addition to visual observation, passive acoustic monitoring would be conducted with Navy assets, such as passive ships sonar systems or sonobuoys, already participating in the activity. Passive acoustic observation would be accomplished through the use of remote acoustic sensors or expendable sonobuoys, or via passive acoustic sensors on submarines when they participate in the proposed action. These assets would only detect vocalizing marine mammals within the frequency bands monitored by Navy personnel. Passive acoustic detections would not provide range or bearing to detected animals, and therefore cannot provide locations of these animals. Passive acoustic detections would be reported to the lookout posted in the aircraft in order to increase vigilance of the visual observation and to the person in control of the activity for their consideration in determining when the mitigation zone is free of visible marine mammals. (L) A mitigation zone with a radius of 2.5 nautical miles around the target ship hulk shall be established for sinking exercises (bin E12). Mitigation would include aerial observation beginning 90 minutes before the first firing, visual observations from vessels throughout the duration of the exercise, and both aerial and vessel observation immediately after any planned or unplanned breaks in weapons firing of longer than 2 hours. Prior to conducting the exercise, the Navy would review remotely sensed sea surface temperature PO 00000 Frm 00058 Fmt 4701 Sfmt 4700 and sea surface height maps to aid in deciding where to release the target ship hulk. (1) The Navy would also monitor using passive acoustics during the exercise. Passive acoustic monitoring would be conducted with Navy assets, such as passive ships sonar systems or sonobuoys, already participating in the activity. These assets would only detect vocalizing marine mammals within the frequency bands monitored by Navy personnel. Passive acoustic detections would not provide range or bearing to detected animals, and therefore cannot provide locations of these animals. Passive acoustic detections would be reported to lookouts posted in aircraft and on vessels in order to increase vigilance of their visual observation. Lookouts will also increase observation vigilance before the use of torpedoes or unguided ordnance with a net explosive weight of 500 lb or greater, or if the Beaufort sea state is a 4 or above. (2) The exercise would cease if a marine mammal is sighted within the mitigation zone. The exercise would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 30 minutes. Upon sinking the vessel, the Navy would conduct post-exercise visual observation of the mitigation zone for 2 hours (or until sunset, whichever comes first). (M) A mitigation zone with a radius of 70 yd (64 m) within 30 degrees on either side of the gun target line on the firing side of the vessel for explosive and non-explosive large-caliber gunnery exercises conducted from a ship. Firing would cease if a marine mammal is sighted within the mitigation zone. Firing would recommence if any one of the following conditions is met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, the mitigation zone has been clear from any additional sightings for a period of 30 minutes, or the vessel has repositioned itself more than 140 yd (128 m) away from the location of the last sighting. (v) Mitigation zones for vessels and in-water devices: (A) A mitigation zone of 500 yd (457 m) for observed whales and 200 yd (183 m) for all other marine mammals (except bow riding dolphins) shall be E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations established for all vessel movement, providing it is safe to do so. (B) A mitigation zone of 250 yd (229 m) shall be established for all towed inwater devices that are towed from a manned platform, providing it is safe to do so. (vi) Mitigation zones for nonexplosive practice munitions: (A) A mitigation zone of 200 yd (183 m) shall be established for nonexplosive small-, medium-, and largecaliber gunnery exercises using a surface target. Mitigation would include visual observation immediately before and during the exercise within a mitigation zone of 200 m around the intended impact location. Firing would cease if a marine mammal is visually detected within the mitigation zone. Firing would recommence if any one of the following conditions are met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, the mitigation zone has been clear from any additional sightings for a period of 10 minutes for a firing aircraft, the mitigation zone has been clear from any additional sightings for a period of 30 minutes for a firing vessel, or the intended target location has been repositioned more than 400 yd (366 m) away from the location of the last sighting and the animal’s estimated course direction. (B) A mitigation zone of 1,000 yd (914 m) shall be established for nonexplosive bombing exercises. Mitigation would include visual observation from the aircraft immediately before the exercise and during target approach within a mitigation zone of 1000 yd (914 m) around the intended impact location. Bombing would cease if a marine mammal is visually detected within the mitigation zone. Bombing would recommence if any one of the following conditions are met: The animal is observed exiting the mitigation zone, the animal is thought to have exited the mitigation zone based on its course and speed and the relative motion between the animal and the source, or the mitigation zone has been clear from any additional sightings for a period of 10 minutes. (3) Stranding Response Plan: (i) The Navy shall abide by the letter of the ‘‘Stranding Response Plan for Major Navy Training Exercises in the MITT Study Area,’’ to include the following measures: (A) Shutdown Procedures—When an Uncommon Stranding Event (USE— defined in § 218.91) occurs during a Major Training Exercise (MTE) in the VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 MITT Study Area, the Navy shall implement the procedures described below. (1) The Navy shall implement a shutdown (as defined § 218.91) when advised by a NMFS Office of Protected Resources Headquarters Senior Official designated in the MITT Study Area Stranding Communication Protocol that a USE involving live animals has been identified and that at least one live animal is located in the water. NMFS and the Navy will maintain a dialogue, as needed, regarding the identification of the USE and the potential need to implement shutdown procedures. (2) Any shutdown in a given area shall remain in effect in that area until NMFS advises the Navy that the subject(s) of the USE at that area die or are euthanized, or that all live animals involved in the USE at that area have left the area (either of their own volition or herded). (3) If the Navy finds an injured or dead animal floating at sea during an MTE, the Navy shall notify NMFS immediately or as soon as operational security considerations allow. The Navy shall provide NMFS with species or description of the animal(s), the condition of the animal(s), including carcass condition if the animal(s) is/are dead, location, time of first discovery, observed behavior (if alive), and photo or video (if available). Based on the information provided, NFMS will determine if, and advise the Navy whether a modified shutdown is appropriate on a case-by-case basis. (4) In the event, following a USE, that qualified individuals are attempting to herd animals back out to the open ocean and animals are not willing to leave, or animals are seen repeatedly heading for the open ocean but turning back to shore, NMFS and the Navy shall coordinate (including an investigation of other potential anthropogenic stressors in the area) to determine if the proximity of mid-frequency active sonar training activities or explosive detonations, though farther than 14 nautical miles from the distressed animal(s), is likely contributing to the animals’ refusal to return to the open water. If so, NMFS and the Navy will further coordinate to determine what measures are necessary to improve the probability that the animals will return to open water and implement those measures as appropriate. (5) Within 72 hours of NMFS notifying the Navy of the presence of a USE, the Navy shall provide available information to NMFS (per the MITT Study Area Communication Protocol) regarding the location, number and types of acoustic/explosive sources, PO 00000 Frm 00059 Fmt 4701 Sfmt 4700 46169 direction and speed of units using midfrequency active sonar, and marine mammal sightings information associated with training activities occurring within 80 nautical miles (148 km) and 72 hours prior to the USE event. Information not initially available regarding the 80-nautical miles (148km), 72-hour period prior to the event will be provided as soon as it becomes available. The Navy will provide NMFS investigative teams with additional relevant unclassified information as requested, if available. (b) [Reserved] § 218.95 Requirements for monitoring and reporting. (a) As outlined in the MITT Study Area Stranding Communication Plan, the Holder of the Authorization must notify NMFS immediately (or as soon as operational security considerations allow) if the specified activity identified in § 218.90 is thought to have resulted in the mortality or injury of any marine mammals, or in any take of marine mammals not identified in § 218.91. (b) The Holder of the LOA must conduct all monitoring and required reporting under the LOA, including abiding by the MITT Monitoring Project Description. (c) General notification of injured or dead marine mammals. Navy personnel shall ensure that NMFS (regional stranding coordinator) is notified immediately (or as soon as operational security considerations allow) if an injured or dead marine mammal is found during or shortly after, and in the vicinity of, an Navy training or testing activity utilizing mid- or high-frequency active sonar, or underwater explosive detonations. The Navy shall provide NMFS with species or description of the animal(s), the condition of the animal(s) (including carcass condition if the animal is dead), location, time of first discovery, observed behaviors (if alive), and photo or video (if available). The Navy shall consult the Stranding Response Plan to obtain more specific reporting requirements for specific circumstances. (d) Vessel strike. In the event that a Navy vessel strikes a whale, the Navy shall do the following: (1) Immediately report to NMFS (pursuant to the established Communication Protocol) the: (i) Species identification if known; (ii) Location (latitude/longitude) of the animal (or location of the strike if the animal has disappeared); (iii) Whether the animal is alive or dead (or unknown); and (iv) The time of the strike. E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 46170 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations (2) As soon as feasible, the Navy shall report to or provide to NMFS, the: (i) Size, length, and description (critical if species is not known) of animal; (ii) An estimate of the injury status (e.g., dead, injured but alive, injured and moving, blood or tissue observed in the water, status unknown, disappeared, etc.); (iii) Description of the behavior of the whale during event, immediately after the strike, and following the strike (until the report is made or the animal is no long sighted); (iv) Vessel class/type and operation status; (v) Vessel length (vi) Vessel speed and heading; and (vii) To the best extent possible, obtain (3) Within 2 weeks of the strike, provide NMFS: (i) A detailed description of the specific actions of the vessel in the 30minute timeframe immediately preceding the strike, during the event, and immediately after the strike (e.g., the speed and changes in speed, the direction and changes in the direction, other maneuvers, sonar use, etc., if not classified); and (ii) A narrative description of marine mammal sightings during the event and immediately after, and any information as to sightings prior to the strike, if available; and (iii) Use established Navy shipboard procedures to make a camera available to attempt to capture photographs following a ship strike. (e) Annual MITT monitoring program report. (1) The Navy shall submit an annual report describing the implementation and results of the MITT Monitoring Program, described in § 218.95. Data standards will be consistent to the extent appropriate across range complexes and study areas to allow for comparison in different geographic locations. Although additional information will be gathered, the protected species observers collecting marine mammal data pursuant to the MITT Monitoring Program shall, at a minimum, provide the same marine mammal observation data required in this section. (2) As an alternative, the Navy may submit a multi-range complex annual monitoring plan report to fulfill this requirement. Such a report would describe progress of knowledge made with respect to monitoring plan study questions across multiple Navy ranges associated with the ICMP. Similar study questions shall be treated together so that progress on each topic shall be summarized across all Navy ranges. The VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 report need not include analyses and content that does not provide direct assessment of cumulative progress on the monitoring plan study questions. The report shall be submitted either 90 days after the calendar year, or 90 days after the conclusion of the monitoring year date to be determined by the Adaptive Management process. (f) Sonar exercise notification. The Navy shall submit to NMFS (specific contact information to be provided in the LOA) either an electronic (preferably) or verbal report within 15 calendar days after the completion of any major exercise indicating: (1) Location of the exercise. (2) Beginning and end dates of the exercise. (3) Type of exercise. (g) Annual MITT exercise and testing report. The Navy shall submit preliminary reports detailing the status of authorized sound sources within 21 days after the anniversary of the date of issuance of the LOA. The Navy shall submit a detailed report 3 months after the anniversary of the date of issuance of the LOA. The detailed annual report shall contain information on Major Training Exercises (MTE), Sinking Exercise (SINKEX) events, and a summary of sound sources used, as described below. 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 detailed report shall contain information identified in § 218.95(e)(1) and (2). (1) Major Training Exercises/SINKEX: (i) This section shall contain the reporting requirements for Coordinated and Strike Group exercises and SINKEX. Coordinated and Strike Group Major Training Exercises include: (A) Joint Multi-Strike Group Exercise (Valiant Shield). (B) Joint Expeditionary Exercise (ii) Exercise information for each MTE: (A) Exercise designator. (B) Date that exercise began and ended. (C) Location (operating area). (D) Number of items or hours (per the LOA) of each sound source bin (impulsive and non-impulsive) used in the exercise. (E) Number and types of vessels, aircraft, etc., participating in exercise. (F) Individual marine mammal sighting info for each sighting during each MTE: (1) Date/time/location of sighting. (2) Species (if not possible, indication of whale/dolphin). (3) Number of individuals. (4) Initial detection sensor. PO 00000 Frm 00060 Fmt 4701 Sfmt 4700 (5) Indication of specific type of platform the observation was made from (including, for example, what type of surface vessel or testing platform). (6) Length of time observers maintained visual contact with marine mammal(s). (7) Sea state. (8) Visibility. (9) Sound source in use at the time of sighting. (10) Indication of whether animal is <200 yd, 200 to 500 yd, 500 to 1,000 yd, 1,000 to 2,000 yd, or >2,000 yd from sound source. (11) Mitigation Implementation— Whether operation of sonar sensor was delayed, or sonar was powered or shut down, and how long the delay was; or whether navigation was changed or delayed. (12) If source in use is a hull-mounted sonar, relative bearing of animal from ship, and estimation of animal’s motion relative to ship (opening, closing, parallel). (13) Observed behavior— Watchstanders shall report, in plain language and without trying to categorize in any way, the observed behavior of the animal(s) (such as animal closing to bow ride, paralleling course/speed, floating on surface and not swimming, etc.) and if any calves present. (iii) An evaluation (based on data gathered during all of the MTEs) of the effectiveness of mitigation measures designed to minimize the received level to which marine mammals may be exposed. This evaluation shall identify the specific observations that support any conclusions the Navy reaches about the effectiveness of the mitigation. (iv) Exercise information for each SINKEX: (A) List of the vessels and aircraft involved in the SINKEX. (B) Location (operating area). (C) Chronological list of events with times, including time of sunrise and sunset, start and stop time of all marine species surveys that occur before, during, and after the SINKEX, and ordnance used. (D) Visibility and/or weather conditions, wind speed, cloud cover, etc. throughout exercise if it changes. (E) Aircraft used in the surveys, flight altitude, and flight speed and the area covered by each of the surveys, given in coordinates, map, or square miles. (F) Passive acoustic monitoring details (number of sonobuoys, area, detections of biologic activity, etc.). (G) Individual marine mammal sighting info for each sighting that required mitigation to be implemented: (1) Date/time/location of sighting. E:\FR\FM\03AUR2.SGM 03AUR2 mstockstill on DSK4VPTVN1PROD with RULES2 Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules and Regulations (2) Species (if not possible, indication of whale/dolphin). (3) Number of individuals. (4) Initial detection sensor. (5) Indication of specific type of platform the observation was made from (including, for example, what type of surface vessel or platform). (6) Length of time observers maintained visual contact with marine mammal(s). (7) Sea state. (8) Visibility. (9) Indication of whether animal is <200 yd, 200–500 yd, 500–1,000 yd, 1,000–2,000 yd, or >2,000 yd from the target. (10) Mitigation implementation— Whether the SINKEX was stopped or delayed and length of delay. (11) Observed behavior— Watchstanders shall report, in plain language and without trying to categorize in any way, the observed behavior of the animals (such as animal closing to bow ride, paralleling course/ speed, floating on surface and not swimming, etc.), and if any calves present. (H) List of the ordnance used throughout the SINKEX and net explosive weight (NEW) of each weapon and the combined NEW. (2) Summary of sources used. (i) This section shall include the following information summarized from the authorized sound sources used in all training and testing events: (A) Total annual or quantity (per the LOA) of each bin of sonar or other nonimpulsive source; (B) Total annual expended/detonated rounds (missiles, bombs, etc.) for each explosive bin; and (C) Improved Extended Echo-Ranging System (IEER)/sonobuoy summary, including: (1) Total expended/detonated rounds (buoys). (2) Total number of self-scuttled IEER rounds. (3) Geographic information presentation. The reports shall present an annual (and seasonal, where practical) depiction of training exercises and testing bin usage geographically across the Study Area. (h) Five-year close-out exercise and testing report.—This report will be included as part of the 2020 annual exercise or testing report. This report will provide the annual totals for each sound source bin with a comparison to the annual allowance and the 5-year total for each sound source bin with a comparison to the 5-year allowance. Additionally, if there were any changes to the sound source allowance, this report will include a discussion of why VerDate Sep<11>2014 18:37 Jul 31, 2015 Jkt 235001 the change was made and include the analysis to support how the change did or did not result in a change in the FEIS and final rule determinations. The report will be submitted 3 months after the expiration of the rule. NMFS will submit comments on the draft close-out report, if any, within 3 months of receipt. The report will be considered final after the Navy has addressed NMFS’ comments, or 3 months after the submittal of the draft if NMFS does not provide comments. § 218.96 Applications for Letters of Authorization. To incidentally take marine mammals pursuant to the regulations in this subpart, the U.S. citizen (as defined by § 216.106 of this chapter) conducting the activity identified in § 218.90(c) (the U.S. Navy) must apply for and obtain either an initial LOA in accordance with § 218.97 or a renewal under § 218.98. § 218.97 Letters of Authorization. (a) An LOA, unless suspended or revoked, will be valid for a period of time not to exceed the period of validity of this subpart. (b) The LOA will set forth: (1) Permissible methods and extent of incidental taking; (2) Means of effecting the least practicable adverse impact on the species, its habitat, and on the availability of the species for subsistence uses (i.e., mitigation); and (3) Requirements for mitigation, monitoring and reporting. (c) Issuance of the LOA will be based on a determination that the total number of marine mammals taken by the activity as a whole will have no more than a negligible impact on the affected species or stock of marine mammal(s). § 218.98 Renewals and modifications of Letters of Authorization. (a) A Letter of Authorization issued under §§ 216.106 and 218.97 of this chapter for the activity identified in § 218.90(c) will be renewed or modified upon request of the applicant, provided that: (1) The proposed specified activity and mitigation, monitoring, and reporting measures, as well as the anticipated impacts, are within the scope of those described and analyzed for these regulations (excluding changes made pursuant to the adaptive management provision of this chapter), and; (2) NMFS determines that the mitigation, monitoring, and reporting measures required by the previous LOA under these regulations were implemented. PO 00000 Frm 00061 Fmt 4701 Sfmt 9990 46171 (b) For LOA modification or renewal requests by the applicant that include changes to the activity or the mitigation, monitoring, or reporting (excluding changes made pursuant to the adaptive management provision of this chapter) that do not change the findings made for the regulations or result in no more than a minor change in the total estimated number of takes (or distribution by species or years). NMFS may publish a notice of proposed LOA in the Federal Register, including the associated analysis illustrating the change, and solicit public comment before issuing the LOA. (c) An LOA issued under §§ 216.106 and 218.97 of this chapter for the activity identified in § 218.94 of this chapter may be modified by NMFS under the following circumstances: (1) Adaptive management. NMFS may modify (including augmenting, changing, or reducing) the existing mitigation, monitoring, or reporting measures (after consulting with the Navy regarding the practicability of the modifications) 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, and reporting measures in an LOA: (A) Results from 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 these regulations or subsequent LOA. (ii) If, through adaptive management, the modifications to the mitigation, monitoring, or reporting measures are substantial, NMFS would publish a notice of proposed LOA in the Federal Register and solicit public comment. (2) Emergencies. 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 § 218.92(c), an LOA may be modified without prior notification and an opportunity for public comment. Notification would be published in the Federal Register within 30 days of the action. [FR Doc. 2015–18633 Filed 7–31–15; 8:45 am] BILLING CODE 3510–22–P E:\FR\FM\03AUR2.SGM 03AUR2

Agencies

[Federal Register Volume 80, Number 148 (Monday, August 3, 2015)]
[Rules and Regulations]
[Pages 46111-46171]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-18633]

[[Page 46111]]

Vol. 80

Monday,

No. 148

August 3, 2015

Part II

Department of Commerce

-----------------------------------------------------------------------

National Oceanic and Atmospheric Administration

-----------------------------------------------------------------------

50 CFR Part 218

Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy
Training and Testing Activities in the Mariana Islands Training and
Testing Study Area; Final Rule

Federal Register / Vol. 80, No. 148 / Monday, August 3, 2015 / Rules
and Regulations

[[Page 46112]]

-----------------------------------------------------------------------

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 218

[Docket No. 140211133-5621-01]
RIN 0648-BD69

Takes of Marine Mammals Incidental to Specified Activities; U.S.
Navy Training and Testing Activities in the Mariana Islands Training
and Testing Study Area

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

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: Upon application from the U.S. Navy (Navy), we (the National
Marine Fisheries Service) are issuing regulations under the Marine
Mammal Protection Act (MMPA) to govern the unintentional taking of
marine mammals incidental to training and testing activities conducted
in the Mariana Islands Training and Testing (MITT) Study Area from
August 2015 through August 2020. These regulations allow us to issue a
Letter of Authorization (LOA) for the incidental take of marine mammals
during the Navy's specified activities and timeframes, set forth the
permissible methods of taking, set forth other means of effecting the
least practicable adverse impact on marine mammal species or stocks and
their habitat, and set forth requirements pertaining to the monitoring
and reporting of the incidental take.

DATES: Effective August 3, 2015 through August 3, 2020.

ADDRESSES: To obtain an electronic copy of the Navy's application or
other referenced documents, visit the Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental/. Documents cited in this rule
may also be viewed, by appointment, during regular business hours, at
1315 East-West Highway, SSMC III, Silver Spring, MD 20912.

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

SUPPLEMENTARY INFORMATION:

Availability

A copy of the Navy's application, which contains a list of the
references used in this document, may be obtained by visiting the
internet at: https://www.nmfs.noaa.gov/pr/permits/incidental. The Navy's
Final Environmental Impact Statement/Overseas Environmental Impact
Statement (FEIS/OEIS) for MITT, which also contains a list of the
references used in this document, may be viewed at https://www.mitt-eis.com. Documents cited in this rule may also be viewed, by
appointment, during regular business hours, at the aforementioned
address (see ADDRESSES).

Background

Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
direct the Secretary of Commerce 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, a notice of a proposed authorization is
provided to the public for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s), will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses (where
relevant), and if the permissible methods of taking and requirements
pertaining to the mitigation, monitoring, and reporting of such takings
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103
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.''
The National Defense Authorization Act of 2004 (NDAA) (Pub. L. 108-
136) removed the ``small numbers'' and ``specified geographical
region'' limitations indicated above and amended the definition of
``harassment'' as it applies to a ``military readiness activity'' to
read as follows (section 3(18)(B) of the MMPA): ``(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].''

Summary of Request

On April 22, 2013, NMFS received an application from the Navy
requesting an LOA for the take of 26 species of marine mammals
incidental to Navy training and testing activities to be conducted in
the MITT Study Area over 5 years. The Navy is requesting regulations
that would establish a process for authorizing take, via one 5-year
LOA, of marine mammals for training and testing activities, proposed to
be conducted from 2015 through 2020. The Study Area includes the
existing Mariana Islands Range Complex (MIRC) and surrounding seas, a
transit corridor between the Mariana Islands and the Navy's Hawaii
Range Complex, and Navy pierside locations where sonar maintenance or
testing may occur (see Figure 2-1 of the Navy's LOA application for a
map of the MITT Study Area). These activities are classified as
military readiness activities. Marine mammals present in the Study Area
may be exposed to sound from active sonar and underwater detonations.
The Navy is requesting authorization to take 26 marine mammal species
by Level B harassment (behavioral) and two species by Level A
harassment (injury).
The Navy's application and the MITT FEIS/OEIS contain acoustic
thresholds that, in some instances, represent changes from what NMFS
has used to evaluate the Navy's activities for previous authorizations.
The revised thresholds, which the Navy developed in coordination with
NMFS, are based on the evaluation and inclusion of new information from
recent scientific studies; a detailed explanation of how they were
derived is provided in the MITT FEIS/OEIS Criteria and Thresholds
Technical Report (available at https://www.mitt-eis.com). The revised
thresholds are adopted for this rulemaking after providing the public
with an opportunity for review and comment via the proposed rule for
this action, which published on March 19, 2014 (79 FR 15388).
Further, more generally, NMFS is committed to the use of the best
available science. NMFS uses an adaptive transparent process that
allows for both timely scientific updates and public input into agency
decisions regarding the use of acoustic research and thresholds. NOAA
is currently in the process of developing Acoustic Guidance (the
Guidance) on thresholds for onset of auditory impacts from exposure to
sound, which will be used to support assessments of the effects of
anthropogenic sound on marine mammals. To develop this Guidance, NOAA
is compiling, interpreting, and synthesizing the best information
currently available on the effects of anthropogenic sound on marine
mammals, and is committed to

[[Page 46113]]

finalizing the Guidance through a systematic, transparent process that
involves internal review, external peer review, and public comment. In
December 2013, NOAA released for public comment draft Acoustic Guidance
that provides acoustic threshold levels for onset of permanent
threshold shift (PTS) and temporary threshold shifts (TTS) in marine
mammals for all sound sources. NOAA has since been working to
incorporate the relevant information received during the public comment
period and to make appropriate changes. In January 2015, while NOAA was
still working to finalize the Guidance, the U.S. Navy provided NOAA
with a technical paper by Finneran (2015) describing Navy's proposed
methodology for updating auditory weighting functions and numeric
thresholds for predicting onset of auditory effects (TTS/PTS
thresholds) on marine animals exposed to active sonars and other active
acoustic sources utilized during Navy training and testing activities.
NOAA is working to evaluate and incorporate the information in Finneran
(2015) into its Acoustic Guidance before it becomes final. Before doing
so, NOAA will complete an independent peer review of the Navy's
technical paper and provide an additional public comment period for the
draft Guidance. After the second peer review and public comment
processes are complete, NOAA will determine how best to incorporate the
Navy's methodology into its final Acoustic Guidance. The Guidance
likely will not be finalized until later this year. Thereafter, any new
Navy modeling based on our final Acoustic Guidance would likely take a
minimum of several months to complete. Consequently, the results of
prior Navy modeling described in this rule represent the best available
estimate of the number and type of take that may result from the Navy's
use of acoustic sources in the MITT Study Area. NOAA's continued
evaluation of all available science for the Acoustic Guidance could
result in changes to the acoustic criteria used to model the Navy's
activities in the MITT Study Area, and, consequently, the enumerations
of ``take'' estimates. However, consideration of the draft Guidance and
information contained in Finneran (2015) does not alter our assessment
of the likely responses of affected marine mammal species to acoustic
sources employed by Navy in the MITT Study Area, or the likely fitness
consequences of those responses. Further, while acoustic criteria may
also inform mitigation and monitoring decisions, the Navy has a robust
adaptive management program that regularly addresses new information
and allows for modification of mitigation and/or monitoring measures as
appropriate.

Description of the Specified Activity

The proposed rule (79 FR 15388, March 19, 2014) and MITT FEIS/OEIS
include a complete description of the Navy's specified activities that
are being authorized in this final rule. Sonar use and underwater
detonations are the stressors most likely to result in impacts on
marine mammals that could rise to the level of harassment. Detailed
descriptions of these activities are provided in the MITT FEIS/OEIS and
LOA application (https://www.nmfs.noaa.gov/pr/permits/incidental/) and
are summarized here.

Overview of Training Activities

The Navy, U.S. Air Force, U.S. Marine Corps, and U.S. Coast Guard
routinely train in the MITT Study Area in preparation for national
defense missions. Training activities are categorized into eight
functional warfare areas (anti-air warfare; amphibious warfare; strike
warfare; anti-surface warfare; anti-submarine warfare; electronic
warfare; mine warfare; and naval special warfare). The Navy determined
that the following stressors used in these warfare areas are most
likely to result in impacts on marine mammals:

Anti-surface warfare (underwater detonations)
Anti-submarine warfare (active sonar, underwater detonations)
Mine warfare (active sonar, underwater detonations)
Naval special warfare (underwater detonations)

Additionally, some activities described as Major Training
Activities in the MITT FEIS/OEIS and other activities are included in
the analysis. The Navy's activities in amphibious warfare, anti-air
warfare, strike warfare, and electronic warfare do not involve
stressors that could result in harassment of marine mammals. Therefore,
these activities are not discussed further. The analysis and rationale
for excluding these warfare areas are contained in the MITT FEIS/OEIS.

Overview of Testing Activities

The Navy researches, develops, tests, and evaluates new platforms,
systems, and technologies. Many tests are conducted in realistic
conditions at sea, and can range in scale from testing new software to
operating portable devices to conducting tests of live weapons to
ensure they function as intended. Testing activities may occur
independently of or in conjunction with training activities. Many
testing activities are conducted similarly to Navy training activities
and are also categorized under one of the primary mission areas. Other
testing activities are unique and are described within their specific
testing categories. The Navy determined that stressors used during the
following testing activities are most likely to result in impacts on
marine mammals:

Naval Air Systems Command (NAVAIR) Testing
[cir] Anti-surface warfare testing (underwater detonations)
[cir] Anti-submarine warfare testing (active sonar, underwater
detonations)
Naval Sea Systems command (NAVSEA) Testing
[cir] New ship construction (active sonar, underwater detonations)
[cir] Life cycle activities (active sonar, underwater detonations)
[cir] Anti-surface warfare/anti-submarine warfare testing (active
sonar, underwater detonations)
[cir] Ship protection systems and swimmer defense testing (active
sonar)
Office of Naval Research (ONR) and Naval Research Laboratory
(NRL) Testing
[cir] ONR/NRL research, development, test, and evaluation (active
sonar)

Other Navy testing activities do not involve stressors that could
result in marine mammal harassment. Therefore, these activities are not
discussed further.

Classification of Non-Impulsive and Impulsive Sources Analyzed

In order to better organize and facilitate the analysis of about
300 sources of underwater non-impulsive sound or impulsive energy, the
Navy developed a series of source classifications, or source bins. This
method of analysis provides the following benefits:
Allows for new sources to be covered under existing
authorizations, as long as those sources fall within the parameters of
a ``bin;''
Simplifies the data collection and reporting requirements
anticipated under the MMPA;
Ensures a conservative approach to all impact analysis
because all sources in a single bin are modeled as the loudest source
(e.g., lowest frequency, highest source level, longest duty cycle, or
largest net explosive weight within that bin);

[[Page 46114]]

Allows analysis to be conducted more efficiently, without
compromising the results;
Provides a framework to support the reallocation of source
usage (hours/explosives) between different source bins, as long as the
total number and severity of marine mammal 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.
A description of each source classification is provided in Tables 1
and 2. Non-impulsive sources are grouped into bins based on the
frequency, source level when warranted, and how the source would be
used. Impulsive bins are based on the net explosive weight of the
munitions or explosive devices. The following factors further describe
how non-impulsive sources are divided:

Frequency of the non-impulsive source:
[cir] Low-frequency sources operate below 1 kilohertz (kHz)
[cir] Mid-frequency sources operate at or above 1 kHz, up to and
including 10 kHz
[cir] High-frequency sources operate above 10 kHz, up to and including
100 kHz
[cir] Very high-frequency sources operate above 100, but below 200 kHz
Source level of the non-impulsive source:
[cir] Greater than 160 decibels (dB), but less than 180 dB
[cir] Equal to 180 dB and up to 200 dB
[cir] Greater than 200 dB

How a sensor is used determines how the sensor's acoustic emissions
are analyzed. Factors to consider include pulse length (time source is
on); beam pattern (whether sound is emitted as a narrow, focused beam,
or, as with most explosives, in all directions); and duty cycle (how
often a transmission occurs in a given time period during an event).
There are also non-impulsive sources with characteristics that are
not anticipated to result in takes of marine mammals. These sources
have low source levels, narrow beam widths, downward directed
transmission, short pulse lengths, frequencies beyond known hearing
ranges of marine mammals, or some combination of these factors. These
sources generally have frequencies greater than 200 kHz and/or source
levels less than 160 dB and are qualitatively analyzed in the MITT
FEIS/OEIS.

Table 1--Impulsive Training and Testing Source Classes Analyzed
----------------------------------------------------------------------------------------------------------------
Source class Representative munitions Net explosive weight (lbs)
----------------------------------------------------------------------------------------------------------------
E1................................. Medium-caliber projectiles. 0.1-0.25 (45.4-113.4 g)
E2................................. Medium-caliber projectiles. 0.26-0.5 (117.9-226.8 g)
E3................................. Large-caliber projectiles.. >0.5-2.5 (>226.8 g-1.1 kg)
E4................................. Improved Extended Echo >2.5-5.0 (1.1-2.3 kg)
Ranging Sonobuoy.
E5................................. 5 in. (12.7 cm) projectiles >5-10 (>2.3-4.5 kg)
E6................................. 15 lb. (6.8 kg) shaped >10-20 (>4.5-9.1 kg)
charge.
E8................................. 250 lb. (113.4 kg) bomb.... >60-100 (>27.2-45.4 kg)
E9................................. 500 lb. (226.8 kg) bomb.... >100-250 (>45.4-113.4 kg)
E10................................ 1,000 lb. (453.6 kg) bomb.. >250-500 (>113.4-226.8 kg)
E11................................ 650 lb. (294.8 kg) mine.... >500-650 (>226.8-294.8 kg)
E12................................ 2,000 lb. (907.2 kg) bomb.. >650-1,000 (>294.8-453.6 kg)
----------------------------------------------------------------------------------------------------------------

Table 2--Non-Impulsive Training and Testing Source Classes Analyzed
------------------------------------------------------------------------
Source class category Source class Description
------------------------------------------------------------------------
Low-Frequency (LF): Sources LF4 Low-frequency
that produce low-frequency LF5 sources equal to
(less than 1 kilohertz 180 dB and up to
[kHz]) signals. 200 dB.
Low-frequency
sources less than
180 dB.
LF6 Low-frequency sonar
currently in
development (e.g.,
anti-submarine
warfare sonar
associated with the
Littoral Combat
Ship).
Mid-Frequency (MF): Tactical MF1 Active hull-mounted
and non-tactical sources surface ship sonar
that produce mid-frequency (e.g., AN/SQS-53C
(1 to 10 kHz) signals. and AN/SQS-60).
MF2 Active hull-mounted
surface ship sonar
(e.g., AN/SQS-56).
MF3 Active hull-mounted
submarine sonar
(e.g., AN/BQQ-10).
MF4 Active helicopter-
deployed dipping
sonar (e.g., AN/AQS-
22 and AN/AQS-13).
MF5 Active acoustic
sonobuoys (e.g.,
DICASS).
MF6 Active underwater
sound signal
devices (e.g., MK-
84).
MF8 Active sources
(greater than 200
dB) not otherwise
binned.
MF9 Active sources
(equal to 180 dB
and up to 200 dB).
MF10 Active sources
(greater than 160
dB, but less than
180 dB) not
otherwise binned.
MF11 Hull-mounted surface
ship sonar with an
active duty cycle
greater than 80%.
MF12 High duty cycle--
variable depth
sonar.
High-Frequency (HF) and Very HF1 Active hull-mounted
High-Frequency (VHF): HF4 submarine sonar
Tactical and non-tactical (e.g., AN/BQQ-10).
sources that produce high- Active mine
frequency (greater than 10 detection,
kHz but less than 200 kHz) classification, and
signals. neutralization
sonar (e.g., AN/SQS-
20).
HF5 Active sources
(greater than 200
dB).
HF6 Active sources
(equal to 180 dB
and up to 200 dB).
Anti-Submarine Warfare ASW1 MF active Deep Water
(ASW): Tactical sources ASW2 Active Distributed
such as active sonobuoys System (DWADS).
and acoustic MF active
countermeasures systems Multistatic Active
used during ASW training Coherent (MAC)
and testing activities. sonobuoy (e.g., AN/
SSQ-125).

[[Page 46115]]

ASW3 MF active towed
active acoustic
countermeasure
systems (e.g., AN/
SLQ-25).
Torpedoes (TORP): Source TORP1 Lightweight torpedo
classes associated with (e.g., MK-46, MK-
active acoustic signals 54, or Anti-Torpedo
produced by torpedoes. Torpedo).
TORP2 Heavyweight torpedo
(e.g., MK-48).
Acoustic Modems (M): Systems M3 Mid-frequency
used to transmit data acoustic modems
acoustically through water. (greater than 190
dB).
Swimmer Detection Sonar SD1 High-frequency
(SD): Systems used to sources with short
detect divers and submerged pulse lengths, used
swimmers. for the detection
of swimmers and
other objects for
the purpose of port
security.
Airguns (AG) \1\: Underwater AG Up to 60 cubic inch
airguns are used during airguns (e.g.,
swimmer defense and diver Sercel Mini-G).
deterrent training and
testing activities.
------------------------------------------------------------------------
\1\ There are no Level A or Level B takes proposed from airguns;
therefore, airguns are not discussed further in this rule.

Proposed Action

The Navy proposes to continue conducting training and testing
activities within the MITT Study Area. The Navy has been conducting
military readiness training and testing activities in the MITT Study
Area for decades.

Training and Testing

The Navy proposes to conduct training and testing activities in the
Study Area as described in Tables 3 and 4. Detailed information about
each proposed activity (stressor, training or testing event,
description, sound source, duration, and geographic location) can be
found in the MITT FEIS/OEIS. NMFS used the detailed information in the
MITT FEIS/OEIS to help analyze the potential impacts to marine mammals.
Table 3 describes the annual number of impulsive source detonations
during training and testing activities within the Study Area, and Table
4 describes the annual number of hours or items of non-impulsive
sources used during training and testing within the Study Area.

Table 3--Annual Number of Impulsive Source Detonations During Training
and Testing Activities in the Study Area
------------------------------------------------------------------------
Annual in-
Explosive class Net explosive weight water
(NEW) detonations
------------------------------------------------------------------------
E1................................ (0.1 lb.-0.25 lb.).. 10,140
E2................................ (0.26 lb.-0.5 lb.).. 106
E3................................ (>0.5 lb.-2.5 lb.).. 932
E4................................ (>2.5 lb.-5 lb.).... 420
E5................................ (>5 lb.-10 lb.)..... 684
E6................................ (>10 lb.-20 lb.).... 76
E8................................ (>60 lb.-100 lb.)... 16
E9................................ (>100 lb.-250 lb.).. 4
E10............................... (>250 lb.-500 lb.).. 12
E11............................... (>500 lb.-650 lb.).. 6
E12............................... (>650 lb.-2,000 lb.) 184
------------------------------------------------------------------------

Table 4--Annual Hours or Items of Non-Impulsive Sources Used During
Training and Testing Activities Within the Study Area
------------------------------------------------------------------------
Source class category Source class Annual use
------------------------------------------------------------------------
Low-Frequency (LF): Sources LF4 123 hours.
that produce signals less
than 1 kHz.
LF5 11 hours.
LF6 40 hours.
Mid-Frequency (MF): Tactical MF1 1,872 hours.
and non-tactical sources from
1 to 10 kHz.
MF2 625 hours.
MF3 192 hours.
MF4 214 hours.
MF5 2,588 items.
MF6 33 items.
MF8 123 hours.
MF9 47 hours.
MF10 231 hours.
MF11 324 hours.
MF12 656 hours.
High-Frequency (HF) and Very HF1 113 hours.
High-Frequency (VHF): HF4 1,060 hours.
Tactical and non-tactical
sources that produce signals
greater than 10 kHz but less
than 200 kHz.
HF5 336 hours.
HF6 1,173 hours.
Anti-Submarine Warfare (ASW): ASW1 144 hours.
Tactical sources used during ASW2 660 items.
anti-submarine warfare
training and testing
activities.
ASW3 3,935 hours.
ASW4 32 items.
Torpedoes (TORP): Source TORP1 115 items.
classes associated with TORP2 62 items.
active acoustic signals
produced by torpedoes.
Acoustic Modems (M): Transmit M3 112 hours.
data acoustically through the
water.
Swimmer Detection Sonar (SD): SD1 2,341 hours.
Used to detect divers and
submerged swimmers.
------------------------------------------------------------------------

[[Page 46116]]

Vessels

Vessels used as part of the proposed action include ships,
submarines, and boats ranging in size from small, 5-m Rigid Hull
Inflatable Boats to 333-m long aircraft carriers. Representative Navy
vessel types, lengths, and speeds used in both training and testing
activities are shown in Table 5. While these speeds are representative,
some vessels operate outside of these speeds due to unique training or
safety requirements for a given event. Examples include increased
speeds needed for flight operations, full speed runs to test
engineering equipment, time critical positioning needs, etc. Examples
of decreased speeds include speeds less than 5 knots or completely
stopped for launching small boats, certain tactical maneuvers, target
launch or retrievals, etc.
The number of Navy vessels in the Study Area varies based on
training and testing schedules. Most activities include either one or
two vessels, with an average of one vessel per activity, and last from
a few hours up to two weeks. Multiple ships, however, can be involved
with major training events, although ships can often operate for
extended periods beyond the horizon and out of visual sight from each
other.

Table 5--Typical Navy Boat and Vessel Types With Length Greater Than 18
Meters Used Within the MITT Study Area
------------------------------------------------------------------------
Example(s)
(specifications in
meters (m) for Typical operating
Vessel type (>18 m) length, metric tons speed (knots)
(mt) for mass, and
knots for speed)
------------------------------------------------------------------------
Aircraft Carrier.............. Aircraft Carrier 10 to 15.
(CVN) length: 333 m
beam: 41 m draft: 12
m displacement:
81,284 mt max.
speed: 30+ knots.
Surface Combatants............ Cruiser (CG) length: 10 to 15.
173 m beam: 17 m
draft: 10 m
displacement: 9,754
mt max. speed: 30+
knots.
Destroyer (DDG)
length: 155 m beam:
18 m draft: 9 m
displacement: 9,648
mt max. speed: 30+
knots.
Frigate (FFG) length:
136 m beam: 14 m
draft: 7 m
displacement: 4,166
mt max. speed: 30+
knots.
Littoral Combat Ship
(LCS) length: 115 m
beam: 18 m draft: 4
m displacement:
3,000 mt max. speed:
40+ knots.
Amphibious Warfare Ships...... Amphibious Assault 10 to 15.
Ship (LHA, LHD)
length: 253 m beam:
32 m draft: 8 m
displacement: 42,442
mt max. speed: 20+
knots.
Amphibious Transport
Dock (LPD) length:
208 m beam: 32 m
draft: 7 m
displacement: 25,997
mt max. speed: 20+
knots.
Dock Landing Ship
(LSD) length: 186 m
beam: 26 m draft: 6
m displacement:
16,976 mt max.
speed: 20+ knots.
Mine Warship Ship............. Mine Countermeasures 5 to 8.
Ship (MCM) length:
68 m beam: 12 m
draft: 4 m
displacement: 1,333
max. speed: 14 knots.
Submarines.................... Attack Submarine 8 to 13.
(SSN) length: 115 m
beam: 12 m draft: 9
m displacement:
12,353 mt max.
speed: 20+ knots.
Guided Missile
Submarine (SSGN)
length: 171 m beam:
13 m draft: 12 m
displacement: 19,000
mt max. speed: 20+
knots.
Combat Logistics Force Ships Fast Combat Support 8 to 12.
\1\. Ship (T-AOE) length:
230 m beam: 33 m
draft: 12 m
displacement: 49,583
max. speed: 25 knots.
Dry Cargo/Ammunition
Ship (T-AKE) length:
210 m beam: 32 m
draft: 9 m
displacement: 41,658
mt max speed: 20
knots.
Fleet Replenishment
Oilers (T-AO)
length: 206 m beam:
30 m draft: 11
displacement: 42,674
mt max. speed: 20
knots.
Fleet Ocean Tugs (T-
ATF) length: 69 m
beam: 13 m draft: 5
m displacement:
2,297 max. speed: 14
knots.
Joint High Speed
Vessel (JHSV) \2\
length: 103 m beam;
28.5 m draft; 4.57 m
displacement; 2,362
mt max speed: 40
knots.
Support Craft/Other........... Landing Craft, 3 to 5.
Utility (LCU)
length: 41 m beam: 9
m draft: 2 m
displacement: 381 mt
max. speed: 11 knots.
Landing Craft,
Mechanized (LCM)
length: 23 m beam: 6
m draft: 1 m
displacement: 107 mt
max. speed: 11 knots.
Support Craft/Other MK V Special Variable.
Specialized High Speed. Operations Craft
length: 25 m beam: 5
m displacement: 52
mt max. speed: 50
knots.
------------------------------------------------------------------------
\1\ CLF vessels are not permanently homeported in the Marianas, but are
used for various fleet support and training support events in the
Study Area.
\2\ Typical operating speed of the Joint High Speed Vessel is 25-32
knots.

Dates and Location

The description of the location of authorized activities has not
changed from what was provided in the proposed rule (79 FR 15388, March
19, 2014; pages 15394-15395) and MITT FEIS/OEIS (https://www.mitt-eis.com). For a complete description, please see those documents.
Training and testing activities will be conducted in the MITT Study
Area for the reasonably foreseeable future. The MITT Study Area is
comprised of the established ranges, operating areas, and special use
airspace in the region of the Mariana Islands that are part of the
Mariana Islands Range Complex (MIRC), its surrounding seas, and a
transit corridor between the Mariana Islands and the Hawaii Range
Complex. The defined Study Area has expanded beyond the areas included
in previous Navy authorizations to include transit routes and pierside
locations. This expansion is not an increase in the Navy's training and
testing area, but rather an increase in the area to be analyzed (i.e.,
not previously analyzed) under an incidental take authorization in
support of the MITT EIS/OEIS. The MIRC, like

[[Page 46117]]

all Navy range complexes, is an organized and designated set of
specifically bounded geographic areas, which includes a water component
(above and below the surface), airspace, and sometimes a land
component. Operating areas (OPAREAs) and special use airspace are
established within each range complex. These designations are further
described in Chapter 2 of the Navy's LOA application.

Description of Marine Mammals in the Area of the Specified Activity

Twenty-six marine mammal species may occur in the Study Area,
including seven mysticetes (baleen whales) and 19 odontocetes (dolphins
and toothed whales). The Description of Marine Mammals in the Area of
the Specified Activities section has not changed from what was in the
proposed rule (79 FR 15388, March 19, 2014; pages 15395-15396). Table 6
of the proposed rule provided a list of marine mammals with possible or
confirmed occurrence within the MITT Study Area, including stock,
abundance, and status. Since publishing the proposed rule, NMFS
released new stock assessment reports for some of the marine mammal
species occurring within the MITT Study Area. The new species abundance
estimates were considered in making our final determinations. The MITT
FEIS/OEIS includes the revised species abundance estimates. Although
not repeated in this final rule, we have reviewed these data,
determined them to be the best available scientific information for the
purposes of the rulemaking, and consider this information part of the
administrative record for this action.
The proposed rule, the Navy's LOA application, and the MITT FEIS/
OEIS include a complete description of information on the status,
distribution, abundance, vocalizations, density estimates, and general
biology of marine mammal species in the Study Area. In addition, NMFS
publishes annual stock assessment reports for marine mammals, including
some stocks that occur within the Study Area (https://www.nmfs.noaa.gov/pr/species/mammals).

Potential Effects of Specified Activities on Marine Mammals

The Navy has requested authorization for the take of marine mammals
that may occur incidental to training and testing activities in the
Study Area. The Navy has analyzed potential impacts to marine mammals
from impulsive and non-impulsive sound sources and vessel strike.
Other potential impacts to marine mammals from training activities
in the Study Area were analyzed in the MITT FEIS/OEIS, in consultation
with NMFS as a cooperating agency, and determined to be unlikely to
result in marine mammal harassment. Therefore, the Navy has not
requested authorization for take of marine mammals that might occur
incidental to other components of their proposed activities. In this
document, NMFS analyzes the potential effects on marine mammals from
exposure to non-impulsive sound sources (sonar and other active
acoustic sources), impulsive sound sources (underwater detonations),
and vessel strikes.
For the purpose of MMPA authorizations, NMFS' effects assessments
serve four primary purposes: (1) To prescribe the permissible methods
of taking (i.e., Level B harassment (behavioral harassment), Level A
harassment (injury), or mortality, including an identification of the
number and types of take that could occur by harassment or mortality)
and to prescribe other means of effecting the least practicable adverse
impact on such species or stock and its habitat (i.e., mitigation); (2)
to determine whether the specified activity would have a negligible
impact on the affected species or stocks of marine mammals (based on
the likelihood that the activity would adversely affect the species or
stock through effects on annual rates of recruitment or survival); (3)
to determine whether the specified activity would have an unmitigable
adverse impact on the availability of the species or stock(s) for
subsistence uses; and (4) to prescribe requirements pertaining to
monitoring and reporting.
This section focuses qualitatively on the different ways that non-
impulsive and impulsive sources may affect marine mammals (some of
which NMFS would not classify as harassment). In the Estimated Take
section, we will relate the potential effects to marine mammals from
non-impulsive and impulsive sources to the MMPA definitions of Level A
and Level B harassment and will attempt to quantify those effects.

Non-Impulsive Sources

Direct Physiological Effects

Based on the literature, there are two basic ways that non-
impulsive sources might directly result in physical trauma or damage:
Noise-induced loss of hearing sensitivity (more commonly-called
``threshold shift'') and acoustically mediated bubble growth.
Separately, an animal's behavioral reaction to an acoustic exposure
could lead to physiological effects that might ultimately lead to
injury or death, which is discussed later in the Stranding section.
Threshold Shift (noise-induced loss of hearing)--When animals
exhibit reduced hearing sensitivity (i.e., sounds must be louder for an
animal to detect them) following exposure to an intense sound or sound
for long duration, it is referred to as a noise-induced threshold shift
(TS). An animal can experience TTS or PTS. TTS can last from minutes or
hours to days (i.e., there is complete recovery), can occur in specific
frequency ranges (i.e., an animal might only have a temporary loss of
hearing sensitivity between the frequencies of 1 and 10 kHz), and can
be of varying amounts (for example, an animal's hearing sensitivity
might be reduced initially by only 6 dB or reduced by 30 dB). PTS is
permanent, but some recovery is possible. PTS can also occur in a
specific frequency range and amount as mentioned above for TTS.
The following physiological mechanisms are thought to play a role
in inducing auditory TS: 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 TS and the frequency range in which it occurs. As
amplitude and duration of sound exposure increase, so, generally, does
the amount of TS, along with the recovery time. For intermittent
sounds, less TS could occur than compared to a continuous exposure with
the same energy (some recovery could occur between intermittent
exposures depending on the duty cycle between sounds) (Kryter et al.,
1966; Ward, 1997). For example, one short but loud (higher SPL) sound
exposure may induce the same impairment as one longer but softer 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, prolonged exposure to sounds
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). Although in the case of mid- and high-frequency
active sonar (MFAS/HFAS), animals are not expected to be exposed to
levels high

[[Page 46118]]

enough or durations long enough to result in PTS.
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).
Although the published body of scientific literature contains
numerous theoretical studies and discussion papers on hearing
impairments that can occur with exposure to a loud sound, only a few
studies provide empirical information on the levels at which noise-
induced loss in hearing sensitivity occurs in nonhuman animals. For
marine mammals, published data are limited to the captive bottlenose
dolphin, beluga, harbor porpoise, and Yangtze finless porpoise
(Finneran et al., 2000, 2002b, 2003, 2005a, 2007, 2010a, 2010b;
Finneran and Schlundt, 2010; Lucke et al., 2009; Mooney et al., 2009a,
2009b; Popov et al., 2011a, 2011b; Kastelein et al., 2012a; Schlundt et
al., 2000; Nachtigall et al., 2003, 2004). For pinnipeds in water, data
are limited to measurements of TTS in harbor seals, an elephant seal,
and California sea lions (Kastak et al., 1999, 2005; Kastelein et al.,
2012b).
Marine mammal hearing plays a critical role in communication with
conspecifics, and 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 occurs
during 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 time when communication is critical
for successful mother/calf interactions could have more serious
impacts. Also, depending on the degree and frequency range, the effects
of PTS on an animal could range in severity, although it is considered
generally more serious 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 one can infer that strategies exist for coping with
this condition to some degree, though likely not without cost.
Acoustically Mediated Bubble Growth--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 of sonar pings or explosion
sounds 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. 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). 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). More recent 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). Although it has been argued that traumas from some recent
beaked whale strandings are consistent with gas emboli and bubble-
induced tissue separations (Jepson et al., 2003), there is no
conclusive evidence of this. However, Jepson et al. (2003, 2005) and
Fernandez et al. (2004, 2005, 2012) concluded that in vivo bubble
formation, which may be exacerbated by

[[Page 46119]]

deep, long-duration, repetitive dives may explain why beaked whales
appear to be particularly vulnerable to sonar exposures. Further
investigation is needed to further assess the potential validity of
these hypotheses. More information regarding hypotheses that attempt to
explain how behavioral responses to non-impulsive sources can lead to
strandings is included in the Stranding and Mortality section.

Acoustic Masking

Marine mammals use acoustic signals for a variety of purposes,
which differ among species, but include communication between
individuals, navigation, foraging, reproduction, and learning about
their environment (Erbe and Farmer, 2000; Tyack, 2000). Masking, or
auditory interference, generally occurs when sounds in the environment
are louder than and of a similar frequency to, auditory signals an
animal is trying to receive. Masking is a phenomenon that affects
animals that are trying to receive acoustic information about their
environment, including sounds from other members of their species,
predators, prey, and sounds that allow them to orient in their
environment. Masking these acoustic signals can disturb the behavior of
individual animals, groups of animals, or entire populations.
The extent of the masking interference depends on the spectral,
temporal, and spatial relationships between the signals an animal is
trying to receive and the masking noise, in addition to other factors.
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.
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 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 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
recent 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.
As mentioned previously, the functional hearing ranges of
mysticetes, odontocetes, and pinnipeds underwater all encompass the
frequencies of the sonar sources used in the Navy's MFAS/HFAS training
exercises. Additionally, almost all 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. For hull-mounted sonar,
which accounts for the largest takes of marine mammals (because of the
source strength and number of hours it's conducted), the pulse length
and low duty cycle of the MFAS/HFAS signal makes it less likely that
masking would occur as a result.

Impaired Communication

In addition to making it more difficult for animals to perceive
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'' 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 animals 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.
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 remain
unknown, like most other trade-offs animals must make, some of these
strategies probably come at a cost (Patricelli et al., 2006). For
example, 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).
Shifting songs and calls to higher frequencies may also impose
energetic costs (Lambrechts, 1996).

Stress Responses

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 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.
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

[[Page 46120]]

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; 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, 1995), altered
metabolism (Elasser et al., 2000), reduced immune competence (Blecha,
2000), and behavioral disturbance. 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 a
risk to the animal's welfare. 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 function,
which impairs those functions that experience the diversion. For
example, when mounting a stress response diverts energy away from
growth in young animals, those animals may experience stunted growth.
When mounting 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 will
last until the animal replenishes its biotic reserves sufficient 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 have also been documented
fairly well through controlled experiments; because this physiology
exists in every vertebrate that has been studied, it is not surprising
that stress responses and their costs have been documented in both
laboratory and free-living 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). Information has also been collected on the physiological
responses of marine mammals to exposure to anthropogenic sounds (Fair
and Becker, 2000; Romano et al., 2002; Wright et al., 2008). 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. 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. The Office of Naval Research hosted a workshop (Effects of
Stress on Marine Mammals Exposed to Sound) in 2009 that focused on this
very topic (ONR, 2009).
Studies of other marine animals and terrestrial animals would also
lead us to expect some marine mammals to 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 (for
example, 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 physiology stress responses of endangered Sonoran pronghorn to
military overflights. Smith et al. (2004a, 2004b), for example,
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.
Hearing is one of the primary senses marine mammals use to gather
information about their environment and to communicate with
conspecifics. Although empirical information on the relationship
between sensory impairment (TTS, PTS, and acoustic masking) on marine
mammals remains limited, it seems reasonable to assume that reducing an
animal's ability to gather information about its environment and to
communicate with other members of its species would be stressful for
animals that use hearing as their primary sensory mechanism. Therefore,
we assume that acoustic exposures sufficient to trigger onset PTS or
TTS would be accompanied by physiological stress responses because
terrestrial animals exhibit those responses under similar conditions
(NRC, 2003). More importantly, marine mammals might experience stress
responses at received levels lower than those necessary to trigger
onset TTS. Based on empirical studies of the time required to recover
from stress responses (Moberg, 2000), we also assume that stress
responses are likely to persist beyond the time interval required for
animals to recover from TTS and might result in pathological and pre-
pathological states that would be as significant as behavioral
responses to TTS.

Behavioral 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 effects whether
it is less likely (habituation) or more likely (sensitization) to
respond to certain sounds in the future (animals can also be innately
pre-disposed 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), 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). 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,

[[Page 46121]]

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.
Exposure of marine mammals to sound sources can result in no
response or responses including, but not limited to: 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 and others in 1995. A more recent
review (Nowacek et al., 2007) addresses studies conducted since 1995
and focuses on observations where the received sound level of the
exposed marine mammal(s) was known or could be estimated. The following
sub-sections 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. Estimates of the types of 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.
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. 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). Flight responses have been
speculated as being a component of marine mammal strandings associated
with sonar activities (Evans and England, 2001).
Response to Predator--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 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.
Diving--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. 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.
Due to past incidents of beaked whale strandings associated with
sonar operations, feedback paths are provided between avoidance and
diving and indirect tissue effects. This feedback accounts for the
hypothesis that variations in diving behavior and/or avoidance
responses can possibly result in nitrogen tissue supersaturation and
nitrogen off-gassing, possibly to the point of deleterious vascular
bubble formation (Jepson et al., 2003). Although hypothetical,
discussions surrounding this potential process are controversial.
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. 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) and sperm whales engaged in foraging dives did
not abandon dives when exposed to distant signatures of seismic airguns
(Madsen et al., 2006). However, Miller et al. (2009) reported buzz
rates (a proxy for feeding) 19 percent lower during exposure to distant
signatures of seismic airguns. 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 sound pressure levels 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 simulated 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

[[Page 46122]]

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).
Preliminary results from the 2010-2011 field season of an ongoing
behavioral response study 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 mild and there was
a quick return to their baseline activity (Southall et al., 2011). A
determination of whether foraging disruptions incur fitness
consequences will require 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. Goldbogen et al., (2013) monitored behavioral responses
of tagged blue whales located in feeding areas when exposed simulated
MFA sonar. Responses varied depending on behavioral context, with deep
feeding whales being more significantly affected (i.e., generalized
avoidance; cessation of feeding; increased swimming speeds; or directed
travel away from the source) compared to surface feeding individuals
that typically showed no change in behavior. Non-feeding whales also
seemed to be affected by exposure. The authors 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.
Breathing--Variations in respiration naturally vary 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 (Southall et al., 2007; Henderson et
al., 2014).
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., caused
avoidance, masking, etc.) and no specific overview is provided here.
However, social disruptions must be considered in context of the
relationships that are affected. Long-term disruptions of mother/calf
pairs or mating displays have the potential to affect the growth and
survival or reproductive effort/success of individuals, respectively.
Vocalizations (also see 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 may result
in response to a need to compete with an increase in background noise
or may reflect an increased vigilance or startle response. For example,
in the presence of low-frequency active sonar, humpback whales have
been observed to increase the length of their ``songs'' (Miller et al.,
2000; Fristrup et al., 2003), possibly due to the overlap in
frequencies between the whale song and the low-frequency active sonar.
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). Killer whales off the northwestern coast of the
U.S. 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.
Avoidance--Avoidance is the displacement of an individual from an
area as a result of the presence of a sound. Richardson et al., (1995)
noted that avoidance reactions are the most obvious manifestations of
disturbance in marine mammals. It 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.
Longer term displacement is possible, however, which can lead to
changes in abundance or distribution patterns of the species in the
affected region if they do not become acclimated to the presence of the
sound (Blackwell et al., 2004; Bejder et al., 2006; Teilmann et al.,
2006). 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), while 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).
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-

[[Page 46123]]

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 (which both
contained mid- and low-frequency components) 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 1000 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 @1-2 kHz every 10
seconds for 10 minutes; Source B: With a 1.0 second upsweep 197 dB @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, ceased feeding during
the approach of the sonar and moved rapidly away from the source. When
exposed to Source B, Kvadsheim and his co-workers 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
orcas were consistent with the results of other studies.
In 2007, the first in a series of behavioral response studies, a
collaboration by the Navy, NMFS, and other scientists showed one beaked
whale (Mesoplodon densirostris) 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 mid-frequency 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 re1[mu]Pa). This sensitivity is manifest 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. The response to such stimuli
appears to involve maximizing the distance from the sound source.
Stimpert et al. (2014) tagged a Baird's beaked whale, which was
subsequently exposed to simulated mid-frequency sonar. 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.
Results from a 2007-2008 study conducted near the Bahamas showed a
change in diving behavior of an adult Blainville's beaked whale to
playback of mid-frequency source and predator sounds (Boyd et al.,
2008; Southall et al. 2009; Tyack et al., 2011). 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 have been 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 mid-frequency active sonar during the 2010 and
2011 field seasons of the southern California behavioral response
study. The 2011 whale was also incidentally exposed to mid-frequency
active sonar from a distant naval exercise. Received levels from the
mid-frequency active sonar signals from the controlled and incidental
exposures were calculated as 84-144 and 78-106 dB re 1 [mu]Pa root mean
square (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. 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. 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 2 hours after mid-
frequency 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 mid-frequency sonar playback was observed on one occasion
(Miller et al., 2011). 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).
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; Tyack et
al., 2011). In the Bahamas, Blainville's beaked whales located on the
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

[[Page 46124]]

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.
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.
There are few empirical studies of avoidance responses of free-
living cetaceans to MFAS. Much more information is available on the
avoidance responses of free-living cetaceans to other acoustic sources,
such as seismic airguns and low-frequency tactical sonar, than MFAS.

Behavioral Responses

Southall et al. (2007) reports the results of the efforts of a
panel of experts in acoustic research from behavioral, physiological,
and physical disciplines that convened and 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, 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 were
not included in the quantitative analysis for the criteria
recommendations. 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. MFAS/HFAS sonar is
considered a non-pulse sound. 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
(incorporated by reference and summarized in the three paragraphs
below).
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 MFAS/HFAS)
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, Acoustic
Thermometry of Ocean Climate (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 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 MFAS/HFAS) 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, while in other cases these responses were not
seen in the 120 to 150 dB 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 MFAS/HFAS) 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),
at least for initial exposures. All recorded exposures above 140 dB
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 is no data to indicate whether other high
frequency cetaceans are as sensitive to anthropogenic sound as harbor
porpoises are.
The studies that address the responses of pinnipeds in water 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 MFAS/HFAS) including: AHDs, ATOC, various non-pulse
sounds used in underwater data communication; underwater drilling, and
construction noise. Few studies exist with enough information to
include them in the analysis. The limited data suggested that exposures
to non-pulse sounds between 90 and 140 dB generally do not result in
strong behavioral responses in pinnipeds in water, but no data exist at
higher received levels.

Potential Effects of Behavioral Disturbance

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 is limited marine mammal data quantitatively 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.
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''

[[Page 46125]]

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. These costs have been documented best in foraging animals,
where vigilance has been shown to substantially reduce feeding rates
(Saino, 1994; Beauchamp and Livoreil, 1997; Fritz et al., 2002).
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
(for example, multiple surface vessels), or when they co-occur with
times that an animal perceives increased risk (for example, when they
are giving birth or accompanied by a calf). Most of the published
literature, however, suggests that direct approaches will increase the
amount of time animals will dedicate to being vigilant. For example,
bighorn sheep and Dall's sheep dedicated more time being vigilant, and
less time resting or foraging, when aircraft made direct approaches
over them (Frid, 2001; Stockwell et al., 1991).
Several authors have established that long-term and intense
disturbance stimuli can cause population declines by reducing the body
condition of individuals that have been disturbed, followed by reduced
reproductive success, reduced survival, or both (Daan et al., 1996;
Madsen, 1994; White, 1983). For example, Madsen (1994) reported that
pink-footed geese 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 disturbed by all-terrain vehicles (Yarmoloy et
al., 1988), caribou disturbed by seismic exploration blasts (Bradshaw
et al., 1998), caribou disturbed by low-elevation military jet-fights
(Luick et al., 1996), and caribou disturbed by low-elevation jet
flights (Harrington and Veitch, 1992). Similarly, a study of elk that
were disturbed experimentally by pedestrians concluded that the ratio
of young to mothers was inversely related to disturbance rate (Phillips
and Alldredge, 2000).
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). For example, a study of grizzly bears reported that
bears disturbed by hikers reduced their energy intake by an average of
12 kcal/minute (50.2 x 10\3\kJ/minute), and spent energy fleeing or
acting aggressively toward hikers (White et al., 1999). Alternately,
Ridgway et al. (2006) reported that increased vigilance in bottlenose
dolphins exposed to sound over a 5-day period did not cause any sleep
deprivation or stress effects such as changes in cortisol or
epinephrine levels.
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 Sharks 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 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-hour
cycle). Substantive behavioral reactions to noise exposure (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). Consequently, a behavioral response lasting less than 1 day and
not recurring on subsequent days is not considered particularly 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 that exercise for multiple days or, further, exposed
in a manner resulting in a sustained multiple day substantive
behavioral responses.
In order to understand how the effects of activities may or may not
impact stocks and populations 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 changes. 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 (below). As depicted, behavioral
and physiological changes can either 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, or
they can have indirect and long-term (chronic) effects on vital rates,
such as when changes in time/energy budgets or

[[Page 46126]]

increased disease susceptibility affect health, which then affects
vital rates (New et al., 2014). In addition to outlining this general
framework and compiling the relevant literature that supports it, New
et al. (2014) have chosen 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
effectively 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, they are a critical first step.
NMFS is constantly evaluating new science and how to best
incorporate it into our decisions. This process involves careful
consideration of new data and how it is best interpreted within the
context of a given management framework. Since preparation of the
proposed rule, NMFS has considered additional studies regarding
behavioral responses that are relevant to the proposed activities and
energy sources. A recent study by Moore and Barlow (2013) emphasizes
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. In addition, Houser et
al., 2013 and Claridge, 2013 were recently published.
Houser et al. (2013) performed a controlled exposure study
involving California sea lions exposed to a simulated mid-frequency
sonar signal. The purpose of this Navy-sponsored study was to determine
the probability and magnitude of behavioral responses by California sea
lions exposed to differing intensities of simulated mid-frequency sonar
signals. Houser et al.'s findings are consistent with current
scientific studies and criteria development concerning marine mammal
reactions to mid-frequency sonar sounds.
Claridge's (2013) Ph.D. thesis investigated the potential effects
exposure to mid-frequency active sonar could have on beaked whale
demographics. In summary, Claridge suggested that lower reproductive
rates observed at the Navy's Atlantic Undersea Test and Evaluation
Center (AUTEC), when compared to a control site, were due to stressors
associated with frequent and repeated use of Navy sonar. However, the
author noted that there may be other unknown differences between the
sites. It is also important to note that there were some relevant
shortcomings of this study. For example, all of the re-sighted whales
during the 5-year study at both sites were female, which Claridge
acknowledged can lead to a negative bias in the abundance estimation.
There was also a reduced effort and shorter overall study period at the
AUTEC site that failed to capture some of the emigration/immigration
trends identified at the control site. Furthermore, Claridge assumed
that the two sites were identical and therefore should have equal
potential abundances; when in reality, there were notable physical
differences. All of the aforementioned studies were considered in NMFS'
determination to issue regulations and associated LOA to the Navy for
their proposed activities in the MITT Study Area.

Stranding and Mortality

When a live or dead marine mammal swims or floats onto shore and
becomes ``beached'' or incapable of returning to sea, the event is
termed a ``stranding'' (Geraci et al., 1999; Perrin and Geraci, 2002;
Geraci and Lounsbury, 2005; NMFS, 2007). The legal definition for a
stranding within the U.S. 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 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.'' (16 U.S.C. 1421h).
Marine mammals are known to strand for a variety of reasons, such
as infectious agents, biotoxicosis, starvation, fishery interaction,
ship strike, unusual oceanographic or weather events, sound exposure,
or combinations of these stressors sustained concurrently or in series.
However, the cause or causes of most strandings are unknown (Geraci et
al., 1976; Eaton, 1979, Odell et al., 1980; Best, 1982). Numerous
studies suggest that the physiology, behavior, habitat relationships,
age, or condition of cetaceans may cause them to strand or might pre-
dispose 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 (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). For reference, between 2001 and
2009, there was an annual average of 1,400 cetacean strandings and
4,300 pinniped strandings along the coasts of the continental U.S. and
Alaska (NMFS, 2011).
Several sources have published lists of mass stranding events of
cetaceans in an attempt to identify relationships between those
stranding events and military sonar (Hildebrand, 2004; IWC, 2005;
Taylor et al., 2004). For example, based on a review of stranding
records between 1960 and 1995, the International Whaling Commission
(2005) identified ten mass stranding events of Cuvier's beaked whales
had been reported and one mass stranding of four Baird's beaked whale.
The IWC concluded that, out of eight stranding events reported from the
mid-1980s to the summer of 2003, seven had been coincident with the use
of tactical mid-frequency sonar, one of those seven had been associated
with the use of tactical low-frequency sonar, and the remaining
stranding event had been associated with the use of seismic airguns.
Most of the stranding events reviewed by the International Whaling
Commission 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.
Between 1960 and 2006, 48 strandings (68 percent) involved beaked
whales, three (4 percent) involved dolphins, and 14 (20 percent)
involved whale species. Cuvier's beaked whales were involved in the
greatest number of these events (48 or 68 percent), followed by sperm
whales (seven or 10 percent), and Blainville's and Gervais' beaked
whales (four each or 6 percent). Naval activities (not just activities
conducted by the U.S. Navy) that might have involved active sonar are
reported to have coincided with nine or 10 (13 to 14 percent) of

[[Page 46127]]

those stranding events. Between the mid-1980s and 2003 (the period
reported by the International Whaling Commission), NMFS identified
reports of 44 mass cetacean stranding events of which at least seven
were coincident with naval exercises that were using MFAS.

Strandings Associated With Impulse Sound

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 5 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 Ocean Beach, California (3 days later
and approximately 11.8 mi. [19 km] from Silver Strand where the
training event occurred), which might also have been related to this
event. Association of the 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 impulse energy (underwater
detonation) that caused mortality or injury to a marine mammal. Despite
this being a rare occurrence, the Navy has 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 these and other
training and testing events are presented in the Mitigation section.

Strandings Associated With MFAS

Over the past 16 years, there have been five stranding events
coincident with military mid-frequency 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). 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 stranding. A number of other stranding events coincident
with the operation of mid-frequency sonar, 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 and only one of these stranding events, the Bahamas (2000),
was associated with exercises conducted by the U.S. Navy. 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. 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 a suite of mitigation intended to more broadly minimize
impacts to marine mammals, the Navy and NMFS have a detailed Stranding
Response Plan that outlines reporting, communication, and response
protocols intended both to minimize the impacts of, and enhance the
analysis of, any potential stranding in areas where the Navy operates.
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 apparent abnormalities or wounds were found.
Examination of photos of the animals, taken soon after their death,
revealed that the eyes of at least four of the individuals were
bleeding. Photos were taken soon after their death (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 were 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 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 history), 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,

[[Page 46128]]

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 hours 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-hr 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, Spain (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 nm (65 km) and at least 10 nm (19
km) 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

[[Page 46129]]

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 near proximity of an international naval
exercise that utilized MFAS and involved numerous surface warships and
several submarines. Strandings began about 4 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, six 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 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; Fern[aacute]ndez et al.,
2012).
Hanalei Bay (2004)--On July 3 and 4, 2004, approximately 150 to 200
melon-headed whales occupied the shallow waters of the Hanalei Bay,
Kaua'i, 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 U.S. 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 9 hours
total between the hours of 1:15 p.m. and 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 use, the animals were herded
out of the Bay.
While causation of this stranding event may never be unequivocally
determined, NMFS consider 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

[[Page 46130]]

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 (but was
similar to the events at Palmyra), 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.
Since that time there have been two ``out of habitat'' or ``near mass
strandings'' of melon-headed whales in the Philippines (Aragones et
al., 2010). Pictures of one of these events depict grouping behavior
like that displayed at Hanalei Bay in July 2004. No naval sonar
activity was noted it the area, although it was suspected by the
authors, based on personal communication with a government fisheries
representative, that dynamite blasting in the area may have occurred
within the days prior to one of the events (Aragones et al., 2010).
Although melon-headed whales entering embayments may be infrequent and
rare, there is precedent for this type of occurrence on other occasions
in the absence of naval activity.
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 Mojacar (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 (these later died). 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 Mojacar 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
nm (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).

Association Between Mass Stranding Events and Exposure to MFAS

Several authors have noted similarities between some of these
stranding incidents: They occurred in islands or archipelagoes with
deep water nearby, several appeared to have been associated with
acoustic waveguides like surface ducting, and the sound fields created
by ships transmitting MFAS (Cox et al., 2006, D'Spain et al., 2006).
Although Cuvier's beaked whales have been the most common species
involved in these stranding events (81 percent of the total number of
stranded animals), other beaked whales (including Mesoplodon europeaus,
M. densirostris, and Hyperoodon ampullatus) comprise 14 percent of the
total. Other species (Stenella coeruleoalba, Kogia breviceps and
Balaenoptera acutorostrata) have stranded, but in much lower numbers
and less consistently than beaked whales.
Based on the evidence available, however, NMFS cannot determine
whether (a) Cuvier's beaked whale is more prone to injury from high-
intensity sound than other species; (b) their behavioral responses to
sound makes them more likely to strand; or (c) they are more likely to
be exposed to MFAS than other cetaceans (for reasons that remain
unknown). Because the association between active sonar exposures and
marine mammals mass stranding events is not consistent--some marine
mammals strand without being exposed to sonar and some sonar
transmissions are not associated with marine mammal stranding events
despite their co-occurrence--other risk factors or a grouping of risk
factors probably contribute to these stranding events.

Behaviorally Mediated Responses to MFAS That May Lead to Stranding

Although the confluence of Navy MFAS with the other contributory
factors noted in the 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 understood, and there is uncertainty
regarding the ordering of effects that led to the stranding. It is
unclear whether beaked

[[Page 46131]]

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 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).
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 kilometers) 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
(also see 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 Ziphius), 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 ascent 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 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). The probability of flight
responses should 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

[[Page 46132]]

closer to the ground (Steidl and Anthony, 1996).
Despite the many theories involving bubble formation (both as a
direct cause of injury (see Acoustically Mediated Bubble Growth
Section) and an indirect cause of stranding (See Behaviorally Mediated
Bubble Growth Section)), 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.

Impulsive 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). In addition, gas-containing
organs including the nasal sacs, larynx, pharynx, trachea, and lungs
may be damaged by compression/expansion caused by the oscillations of
the blast gas bubble (Reidenberg and Laitman, 2003). 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 susceptible 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). Sound-related trauma can be lethal or sublethal. 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).
There have been fewer studies addressing the behavioral effects of
explosives on marine mammals compared to MFAS/HFAS. However, though the
nature of the sound waves emitted from an explosion are different (in
shape and rise time) from MFAS/HFAS, NMFS still anticipates the same
sorts of behavioral responses to result from repeated explosive
detonations (a smaller range of likely less severe responses (i.e., not
rising to the level of MMPA harassment) would be expected to occur as a
result of exposure to a single explosive detonation that was not
powerful enough or close enough to the animal to cause TTS or injury).
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 [micro]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 [micro]Pa.
Gray whales migrating along the U.S. 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 5-8 km from
a seismic array during observational studies and controlled exposure
experiments in western Australia (McCauley, 1998; 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.
Seismic pulses at average received levels of 131 dB re 1
micropascal squared second ([micro]Pa\2\-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 [micro]Pa peak-to-peak). These studies
demonstrate that even low levels of noise received far from the noise
source can induce behavioral responses.
Madsen et al. (2006) and Miller et al. (2009) tagged and monitored
eight sperm whales in the Gulf of Mexico exposed to seismic airgun
surveys. Sound sources were from approximately 2 to 7 nm away from the
whales and based on multipath propagation received levels were as high
as 162 dB SPL re 1 [micro]Pa with energy content greatest between 0.3
and 3.0 kHz (Madsen, 2006). The whales showed no horizontal avoidance,
although the whale that was approached most closely had an extended
resting period and did not resume foraging until the airguns had ceased
firing (Miller et al., 2009). The remaining whales continued to

[[Page 46133]]

execute foraging dives throughout exposure; however, swimming movements
during foraging dives were 6 percent lower during exposure than control
periods, suggesting subtle effects of noise on foraging behavior
(Miller et al., 2009). Captive bottlenose dolphins sometimes vocalized
after an exposure to impulse sound from a seismic watergun (Finneran et
al., 2010a).
A review of behavioral reactions by pinnipeds to impulse noise can
be found in Richardson et al. (1995) and Southall et al. (2007).
Blackwell et al. (2004) observed that ringed seals exhibited little or
no reaction to pipe-driving noise with mean underwater levels of 157 dB
re 1 [micro]Pa rms and in air levels of 112 dB re 20 [micro]Pa,
suggesting that the seals had habituated to the noise. In contrast,
captive California sea lions avoided sounds from an impulse source at
levels of 165-170 dB re 1 [micro]Pa (Finneran et al., 2003b).
Experimentally, G[ouml]tz and Janik (2011) tested underwater, startle
responses to a startling sound (sound with a rapid rise time and a 93
dB sensation level [the level above the animal's threshold at that
frequency]) and a non-startling sound (sound with the same level, but
with a slower rise time) in wild-captured gray seals. The animals
exposed to the startling treatment avoided a known food source, whereas
animals exposed to the non-startling treatment did not react or
habituated during the exposure period. The results of this study
highlight the importance of the characteristics of the acoustic signal
in an animal's response of habituation.

Vessels

Commercial and Navy ship strikes of cetaceans can cause major
wounds, which may lead to the death of the animal. An animal at the
surface could be struck directly by a vessel, a surfacing animal could
hit the bottom of a vessel, or an animal just below the surface could
be cut by a vessel's propeller. The severity of injuries typically
depends on the size and speed of the vessel (Knowlton and Kraus, 2001;
Laist et al., 2001; Vanderlaan and Taggart, 2007). The most vulnerable
marine mammals 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., the sperm whale). In addition, some baleen whales,
such as the North Atlantic right whale, 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. Smaller marine mammals (e.g., bottlenose dolphin) move quickly
through the water column and are often seen riding the bow wave of
large ships. Marine mammal responses to vessels may include avoidance
and changes in dive pattern (NRC, 2003).
An examination of all known ship strikes from all shipping sources
(civilian and military) indicates vessel speed is a principal factor in
whether a vessel strike results in death (Knowlton and Kraus, 2001;
Laist et al., 2001; Jensen and Silber, 2003; Vanderlaan and Taggart,
2007). In assessing records in which vessel speed was known, Laist et
al. (2001) found a direct relationship between the occurrence of a
whale strike and the speed of the vessel involved in the collision. The
authors concluded that most deaths occurred when a vessel was traveling
in excess of 13 knots.
Jensen and Silber (2003) detailed 292 records of known or probable
ship strikes of all large whale species from 1975 to 2002. Of these,
vessel speed at the time of collision was reported for 58 cases. Of
these cases, 39 (or 67 percent) resulted in serious injury or death (19
of those resulted in serious injury as determined by blood in the
water, propeller gashes or severed tailstock, and fractured skull, jaw,
vertebrae, hemorrhaging, massive bruising or other injuries noted
during necropsy and 20 resulted in death). Operating speeds of vessels
that struck various species of large whales ranged from 2 to 51 knots.
The majority (79 percent) of these strikes occurred at speeds of 13
knots or greater. The average speed that resulted in serious injury or
death was 18.6 knots. Pace and Silber (2005) found that the probability
of death or serious injury increased rapidly with increasing vessel
speed. Specifically, the predicted probability of serious injury or
death increased from 45 to 75 percent as vessel speed increased from 10
to 14 knots, and exceeded 90 percent at 17 knots. Higher speeds during
collisions result in greater force of impact and also appear to
increase the chance of severe injuries or death. While modeling studies
have suggested that hydrodynamic forces pulling whales toward the
vessel hull increase with increasing speed (Clyne, 1999; Knowlton et
al., 1995), this is inconsistent with Silber et al. (2010), which
demonstrated that there is no such relationship (i.e., hydrodynamic
forces are independent of speed).
The Jensen and Silber (2003) report notes that the database
represents a minimum number of collisions, because the vast majority
probably goes undetected or unreported. In contrast, Navy vessels are
likely to detect any strike that does occur, and they are required to
report all ship strikes involving marine mammals. Overall, the
percentages of Navy traffic relative to overall large shipping traffic
are very small (on the order of 2 percent).
There are no records of any Navy vessel strikes to marine mammals
during training or testing activities in the MITT Study Area. There
have been Navy strikes of large whales in areas outside the Study Area,
such as Hawaii and Southern California. However, these areas differ
significantly from the Study Area given that both Hawaii and Southern
California have a much higher number of Navy vessel activities and much
higher densities of large whales.
Other efforts have been undertaken to investigate the impact from
vessels (both whale-watching and general vessel traffic noise) and
demonstrated impacts do occur (Bain, 2002; Erbe, 2002; Lusseau, 2009;
Williams et al., 2006, 2009, 2011b, 2013, 2014a, 2014b; Noren et al.,
2009; Read et al., 2014; Rolland et al., 2012; Pirotta et al., 2015).
This body of research for the most part has investigated impacts
associated with the presence of chronic stressors, which differ
significantly from generally intermittent Navy training and testing
activities. For example, in an analysis of energy costs to killer
whales, Williams et al. (2009) suggested that whale-watching in the
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) recently reported
on research in the Salish Sea 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.

Mitigation

Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the
``permissible methods of taking pursuant to such activity, and other
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.'' NMFS' duty under
this ``least practicable adverse impact'' standard is to prescribe
mitigation reasonably designed to minimize, to the extent practicable,
any adverse population-level impacts, as well as habitat impacts. While
population-level

[[Page 46134]]

impacts are minimized by reducing impacts on individual marine mammals,
not all takes have a reasonable potential for translating to
population-level impacts. NMFS' objective under the ``least practicable
adverse impact'' standard is to design mitigation targeting those
impacts on individual marine mammals that are reasonably likely to
contribute to adverse population-level effects.
The NDAA of 2004 amended the MMPA as it relates to military-
readiness activities and the ITA process such that ``least practicable
adverse impact'' shall include consideration of personnel safety,
practicality of implementation, and impact on the effectiveness of the
``military readiness activity.'' The training and testing activities
described in the Navy's LOA application are considered military
readiness activities.
In Conservation Council for Hawaii v. National Marine Fisheries
Service, No. 1:13-cv-00684 (D. Hawaii March 31, 2015), the court stated
that NMFS ``appear[s] to think that [it] satisf[ies] the statutory
`least practicable adverse impact' requirement with a `negligible
impact' finding.'' In light of the court's decision, we take this
opportunity to make clear our position that the ``negligible impact''
and ``least practicable adverse impact'' requirements are distinct,
even though the focus of both is on population-level impacts.
A population-level impact is an impact on the population numbers
(survival) or growth and reproductive rates (recruitment) of a
particular marine mammal species or stock. As we noted in the preamble
to our general MMPA implementing regulations, not every population-
level impact violates the negligible impact requirement. As we
explained, 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 . . . [T]he key factor
is the significance of the level of impact on rates of recruitment or
survival. Only insignificant impacts on long-term population levels and
trends can be treated as negligible.'' See 54 FR 40338, 40341-42 (Sept
29, 1989). Nevertheless, while insignificant impacts on population
numbers or growth rates may satisfy the negligible impact requirement,
such impacts still must be mitigated, to the extent practicable, under
the ``least practicable adverse impact'' requirement. Thus, the
negligible impact and least practicable adverse impact requirements are
clearly distinct, even though both focus on population-level effects.
As explained in the proposed rule, any mitigation measure(s)
prescribed by NMFS should be able to accomplish, have a reasonable
likelihood of accomplishing (based on current science), or contribute
to accomplishing one or more of the general goals listed below:
a. Avoid or minimize injury or death of marine mammals wherever
possible (goals b, c, and d may contribute to this goal).
b. Reduce the numbers of marine mammals (total number or number at
biologically important time or location) exposed to received levels of
MFAS/HFAS, underwater detonations, or other activities expected to
result in the take of marine mammals (this goal may contribute to a,
above, or to reducing harassment takes only).
c. Reduce the number of times (total number or number at
biologically important time or location) individuals would be exposed
to received levels of MFAS/HFAS, underwater detonations, or other
activities expected to result in the take of marine mammals (this goal
may contribute to a, above, or to reducing harassment takes only).
d. Reduce the intensity of exposures (either total number or number
at biologically important time or location) to received levels of MFAS/
HFAS, underwater detonations, or other activities expected to result in
the take of marine mammals (this goal may contribute to a, above, or to
reducing the severity of harassment takes only).
e. Avoid or minimize adverse effects to marine mammal habitat,
paying special attention to the food base, activities that block or
limit passage to or from biologically important areas, permanent
destruction of habitat, or temporary destruction/disturbance of habitat
during a biologically important time.
f. For monitoring directly related to mitigation--increase the
probability of detecting marine mammals, thus allowing for more
effective implementation of the mitigation (shut-down zone, etc.).
Our final evaluation of measures that meet one or more of the above
goals includes 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 population-level impacts to marine mammal species and stocks and
impacts to their habitat; the proven or likely efficacy of the
measures; and the practicability of the suite of measures for applicant
implementation, including consideration of personnel safety,
practicality of implementation, and impact on the effectiveness of the
military readiness activity.
NMFS reviewed the proposed activities and the suite of proposed
mitigation measures as described in the Navy's LOA application to
determine if they would result in the least practicable adverse effect
on marine mammals. NMFS described the Navy's proposed mitigation
measures in detail in the proposed rule (79 FR 15388, March 19, 2014;
pages 15414-15422), and they have not changed. NMFS worked with the
Navy in the development of the Navy's initially proposed measures, and
they are informed by years of experience and monitoring. As described
in the Mitigation Conclusions below and in responses to comments, and
in the MITT FEIS/OEIS, additional measures were considered and
analyzed, but ultimately not chosen for implementation. Below are the
mitigation measures as agreed upon by the Navy and NMFS. For additional
details regarding the Navy's mitigation measures, see Chapter 5 in the
MITT FEIS/OEIS.
At least one Lookout during applicable training and
testing activities;
Mitigation zones ranging from 70 yards (yd) (64 m) to 2.5
nautical miles (nm) during applicable activities that involve the use
of impulse and non-impulse sources to avoid or reduce the potential for
onset of the lowest level of injury, PTS, out to the predicted maximum
range (Tables 6 and 7);
Mitigation zones of 500 yd (457 m) for whales and 200 yd
(183 m) for all other marine mammals (except bow riding dolphins)
during vessel movement, and a mitigation zone of 250 yd (229 m) for
marine mammals during use of towed in-water devices being towed from
manned platforms; and
Mitigation zones ranging from 200 yd (183 m) to 1,000 yd
(914 m) during activities that involve the use of non-explosive
practice munitions.

[[Page 46135]]

Table 6--Predicted Ranges to TTS, PTS, and Recommended Mitigation Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
Predicted average
Activity category Bin (representative Predicted average (longest) range to Predicted maximum Recommended
source)* (longest) range to TTS PTS range to PTS mitigation zone
--------------------------------------------------------------------------------------------------------------------------------------------------------
Non-Impulse Sound
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-Frequency and Hull-Mounted Mid- MF1 (SQS-53 ASW hull- Page 83............... Page 83.............. Not Applicable....... 6 dB power down at
Frequency Active Sonar. mounted sonar). 3,281 yd (3.5 km) for 100 yd (91 m) for one 1,000 yd. (914 m);
one ping. ping. 4 dB power down at
500 yd. (457 m); and
shutdown at 200 yd.
(183 m).
LF4 (low-frequency 3,821 yd. (3.5 km) for 100 yd. (91 m) for Not Applicable....... 200 yd. (183 m).**
sonar) **. one ping. one ping.
--------------------------------------------------------------------------------------------------------------------------------------------------------
High-Frequency and Non-Hull Mounted MF4 (AQS-22 ASW 230 yd. (210 m) for 20 yd. (18 m) for one Not Applicable....... 200 yd. (183 m).
Mid-Frequency Active Sonar. dipping sonar). one ping. ping.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Explosive and Impulse Sound
--------------------------------------------------------------------------------------------------------------------------------------------------------
Improved Extended Echo Ranging E4 (Explosive 434 yd. (397 m)....... 156 yd. (143 m)...... 563 yd. (515 m)...... 600 yd. (549 m).
Sonobuoys. sonobuoy).
Explosive Sonobuoys using 0.6-2.5 E3 (Explosive 290 yd. (265 m)....... 113 yd. (103 m)...... 309 yd. (283 m)...... 350 yd. (320 m).
lb. NEW. sonobuoy).
Anti-Swimmer Grenades.............. E2 (Up to 0.5 lb. NEW) 190 yd. (174 m)....... 83 yd. (76 m)........ 182 yd. (167 m)...... 200 yd. (183 m).
--------------------------------------------------------------------------------------------------------------------
Mine Countermeasure and NEW dependent (see Table 7).
Neutralization Activities Using
Positive Control Firing Devices.
--------------------------------------------------------------------------------------------------------------------
Mine Neutralization Diver-Placed E6 (Up to 20 lb. NEW). 407 yd. (372 m)....... 98 yd. (90 m)........ 102 yd. (93 m)....... 1,000 yd. (914 m).
Mines Using Time-Delay Firing
Devices.
Gunnery Exercises--Small- and E2 (40 mm projectile). 190 yd. (174 m)....... 83 yd. (76 m)........ 182 yd. (167 m)...... 200 yd. (183 m).
Medium-Caliber (Surface Target).
Gunnery Exercises--Large-Caliber E5 (5 in. projectiles 453 yd. (414 m)....... 186 yd. (170 m)...... 526 yd. (481 m)...... 600 yd. (549 m).
(Surface Target). at the surface ***).
Missile Exercises up to 250 lb. NEW E9 (Maverick missile). 949 yd. (868 m)....... 398 yd. (364 m)...... 699 yd. (639 m)...... 900 yd. (823 m).
(Surface Target).
Missile Exercises > 250 to 500 lb. E10 (Harpoon missile). 1,832 yd. (1,675 m)... 731 yd. (668 m)...... 1,883 yd. (1,721 m).. 2,000 yd. (1.8 km).
NEW (Surface Target).
Bombing Exercises.................. E12 (MK-84 2,000 lb. 2,513 yd. (2.3 km).... 991 yd. (906 m)...... 2,474 yd. (2.3 km)... 2,500 yd. (2.3
bomb). km).****
Torpedo (Explosive) Testing........ E11 (MK-48 torpedo)... 1,632 yd. (1.5 km).... 697 yd. (637 m)...... 2,021 yd. (1.8 km)... 2,100 yd. (1.9 km).\
Sinking Exercises.................. E12 (Various sources 2,513 yd. (2.3 km).... 991 yd. (906 m)...... 2,474 yd. (2.3 km)... 2.5 nm.****
up to the MK-84 2,000
lb. bomb).
--------------------------------------------------------------------------------------------------------------------------------------------------------
ASW = anti-submarine warfare, km = kilometers, lb.= pound(s), m = meters, mm = millimeters, NEW = net explosive weight, nm = nautical miles, PTS =
Permanent Threshold Shift, TTS = Temporary Threshold Shift, yd. = yards
* This table does not provide an inclusive list of source bins; bins presented here represent the source bin with the largest range to effects within
the given activity category.
** The representative source bin and mitigation zone applies to sources that cannot be powered down (e.g., bins LF4 and LF5).
*** The representative source bin E5 has different range to effects depending on the depth of activity occurrence (at the surface or at various depths).
**** Recommended mitigation zones are larger than the modeled injury zones to account for multiple types of sources or charges being used.

[[Page 46136]]

Table 7--Predicted Ranges to Effects and Mitigation Zone Radius for Mine Countermeasure and Neutralization Activities Using Positive Control Firing Devices
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
General mine countermeasure and neutralization activities using Mine countermeasure and neutralization activities using diver
positive control firing devices * placed charges under positive control **
-----------------------------------------------------------------------------------------------------------------------------------
Charge size net explosive weight (bins) Predicted Predicted Predicted Predicted Predicted Predicted
average range average range maximum range Recommended average range average range maximum range Recommended
to TTS to PTS to PTS mitigation zone to TTS to PTS to PTS mitigation zone
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2.5-5 lb. (1.2-2.3 kg) (E4)................................. 434 yd 197 yd 563 yd 600 yd. 545 yd 169 yd 301 yd 350 yd
(474 m) (180 m) (515 m) (549 m) (498 m) (155 m) (275 m) (320 m).
5-10 lb. (2.7-4.5 kg) (E5).................................. 525 yd 204 yd 649 yd 800 yd 587 yd 203 yd 464 yd 500 yd
(480 m) (187 m) (593 m) (732 m) (537 m) (185 m) (424 m) (457 m).
>10-20 lb. (5-9.1 kg) (E6).................................. 766 yd 288 yd 648 yd 800 yd 647 yd 232 yd 469 yd 500 yd
(700 m) (263 m) (593 m) (732 m) (592 m) (212 m) (429 m) (457 m)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
PTS: permanent threshold shift; TTS: temporary threshold shift.
* These mitigation zones are applicable to all mine countermeasure and neutralization activities conducted in all locations specified in Chapter 2 of the Navy's LOA application.
** These mitigation zones are only applicable to mine countermeasure and neutralization activities involving the use of diver placed charges. These activities are conducted in shallow-water
and the mitigation zones are based only on the functional hearing groups with species that occur in these areas (mid-frequency cetaceans and sea turtles).

Stranding Response Plan

NMFS and the Navy developed a Stranding Response Plan for MIRC in
2010 as part of the incidental take authorization process. In addition,
Regional Stranding Implementation Assistance Plans for MIRC were
established in 2011 per a Navy-NMFS MOU. The Stranding Response Plan is
specifically intended to outline the applicable requirements in the
event that a marine mammal stranding is reported in the MIRC during a
major training exercise. NMFS considers all plausible causes within the
course of a stranding investigation and these plans in no way presume
that any strandings in a Navy range complex are related to, or caused
by, Navy training and testing activities, absent a determination made
during investigation. The plans are designed to address mitigation,
monitoring, and compliance. The Navy worked with NMFS to refine these
plans for the new MITT Study Area (to include regionally specific plans
that include more logistical detail) and these revised plans are
available here: https://www.nmfs.noaa.gov/pr/permits/incidental/.
Modifications to the Stranding Response Plan may also be made through
the adaptive management process.

Mitigation Conclusions

NMFS has carefully evaluated the Navy's proposed mitigation
measures--many of which were developed with NMFS' input during the
first phase of authorizations--and considered a range of other measures
in the context of ensuring that NMFS prescribes the means of effecting
the least practicable adverse impact on the affected marine mammal
species and stocks and their habitat. Based on our evaluation of the
Navy's proposed measures, as well as other measures considered by NMFS,
NMFS has determined that the Navy's proposed mitigation measures
(especially when the adaptive management component is taken into
consideration (see Adaptive Management, below)) are adequate means of
effecting the least practicable adverse impacts on marine mammals
species or stocks and their habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, while
also considering personnel safety, practicality of implementation, and
impact on the effectiveness of the military readiness activity.

Monitoring

Section 101(a)(5)(A) of the MMPA states that in order to issue an
ITA 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 LOAs
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.
NMFS provided an overview of Navy monitoring and research,
highlighted recent findings, and explained the Navy's new approach to
monitoring in the proposed rule (79 FR 15388; pages 15422-15426). Below
is a summary of the Navy's Integrated Comprehensive Monitoring Program
(ICMP) and the Navy's Strategic Planning Process for Marine Species
Monitoring.

Integrated Comprehensive Monitoring Program

The Navy's ICMP is intended to coordinate 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.
Although the ICMP does not specify actual monitoring field work or
projects, it does establish top-level goals that have been developed in
coordination with NMFS. As the ICMP is implemented, detailed and
specific studies will be developed which support the Navy's 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
one or more of the following top-level goals:
An increase in our understanding of the likely occurrence
of marine mammals and/or ESA-listed marine species in the vicinity of
the action (i.e., presence, abundance, distribution, and/or density of
species);
An increase in our understanding of the nature, scope, or
context of the likely exposure of marine mammals and/or ESA-listed
species to any of the potential stressor(s) associated with the action
(e.g., tonal and impulsive sound), through better understanding of one
or more of the following: (1) the action and the environment in which
it occurs (e.g., sound source characterization, propagation, and
ambient noise levels);

[[Page 46137]]

(2) the affected species (e.g., life history or dive patterns); (3) the
likely co-occurrence of marine mammals and/or ESA-listed marine species
with the action (in whole or part) associated with specific adverse
effects, and/or; (4) the likely biological or behavioral context of
exposure to the stressor for the marine mammal and/or ESA-listed marine
species (e.g., age class of exposed animals or known pupping, calving
or feeding areas);
An increase in our 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 our 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 effects on annual rates of recruitment or survival);
An increase in our understanding of the effectiveness of
mitigation and monitoring measures;
A better understanding and record of the manner in which
the authorized entity complies with the ITA and Incidental Take
Statement;
An increase in the probability of detecting marine mammals
(through improved technology or methods), both specifically within the
safety zone (thus allowing for more effective implementation of the
mitigation) and in general, to better achieve the above goals; and
A reduction in the adverse impact of activities to the
least practicable level, as defined in the MMPA.
Monitoring addresses the ICMP top-level goals through a collection
of specific regional and ocean basin studies based on scientific
objectives. Quantitative metrics of monitoring effort (e.g., 20 days of
aerial surveys) are not a specific requirement. The adaptive management
process and reporting requirements serve as the basis for evaluating
performance and compliance, primarily considering the quality of the
work and results produced, as well as peer review and publications, and
public dissemination of information, reports, and data. Details of the
ICMP and all MIRC monitoring reports are available online (https://www.navymarinespeciesmonitoring.us/).

Strategic Planning Process for Marine Species Monitoring

The Navy also developed the Strategic Planning Process for Marine
Species Monitoring, which 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 top-level goals, a conceptual framework
incorporating a progression of knowledge, and consultation with a
Scientific Advisory Group and other regional experts. The Strategic
Planning Process for Marine Species Monitoring has been used to set
intermediate scientific objectives, identify potential species of
interest at a regional scale, and evaluate and select specific
monitoring projects to fund or continue supporting for a given fiscal
year. This process would also address 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. The Strategic Planning Process for Marine
Species Monitoring is also available online (https://www.navymarinespeciesmonitoring.us/).

Past Monitoring in the MITT Study Area

NMFS has received multiple years' worth of annual exercise and
monitoring reports addressing active sonar use and explosive
detonations within the MIRC 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 Study Area. The Navy's annual
exercise and monitoring reports may be viewed at: https://www.nmfs.noaa.gov/pr/permits/incidental/ and https://www.navymarinespeciesmonitoring.us. NMFS' summary of the Navy's annual
monitoring reports was included in the proposed rule (79 FR 15388,
March 19, 2014; pages 15423-15424). The Navy has since submitted to
NMFS the 5-year Comprehensive Monitoring Report for MIRC, which is
available at: https://www.nmfs.noaa.gov/pr/permits/incidental/.

Proposed Monitoring for the MITT Study Area

Based on discussions between the Navy and NMFS, future monitoring
should address the ICMP top-level goals through a collection of
specific regional and ocean basin studies based on scientific
objectives. Monitoring would follow the strategic planning process and
conclusions from adaptive management review by shifting from applying
quantitative effort-based metrics, and instead demonstrating progress
on the goals of specific scientific monitoring questions. The adaptive
management process and reporting requirements would serve as the basis
for evaluating performance and compliance, primarily considering the
quality of the work and results produced, as well as peer review and
publications, and public dissemination of information, reports, and
data. The strategic planning process would be used to set intermediate
scientific objectives, identify potential species of interest at a
regional scale, and evaluate and select specific monitoring projects to
fund or continue supporting for a given fiscal year. The strategic
planning process would also address 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.
The Scientific Advisory Group (SAG) confirmed the Navy/NMFS
decision made in 2009 that because so little is known about species
occurrence in this area, the priority for the MIRC should be
establishing basic marine mammal occurrence. Passive acoustic
monitoring, small boat surveys, biopsy sampling, satellite tagging, and
photo-identification are all appropriate methods for evaluating marine
mammal occurrence and abundance in the MITT Study Area. Fixed acoustic
monitoring and development of local expertise ranked highest among the
SAG's recommended monitoring methods for the area. There is an
especially high level of return for monitoring around the Mariana
Islands because so little is currently known about this region.
Specific monitoring efforts would result from future Navy/NMFS
monitoring program management.
A more detailed description of the Navy's planned projects starting
in 2015 (and some continuing from previous years) is available at the
Navy's Marine Species Monitoring web portal: https://www.navymarinespeciesmonitoring.us/. The Navy will update the status of
its monitoring program and funded projects through their Marine Species
Monitoring web portal. NMFS will provide one public comment period on
the Navy's monitoring program during the 5-year regulations. At this
time, the public will have an opportunity (likely in the second or
third year) to comment specifically on the Navy's MITT monitoring
projects and data collection

[[Page 46138]]

to date, as well as planned projects for the remainder of the
regulations.
Through the adaptive management process (including annual
meetings), the Navy will coordinate with NMFS and the Marine Mammal
Commission (Commission) to review and provide input for projects that
will meet the scientific objectives that are used to guide development
of individual monitoring projects. The adaptive management process will
continue to serve as the primary venue for both NMFS and the Commission
to provide input on the Navy's monitoring program, including ongoing
work, future priorities, and potential new projects. The Navy will
continue to submit annual monitoring reports to NMFS as part of the
MITT rulemaking and LOA requirements. Each annual report will contain a
section describing the adaptive management process and summarize the
Navy's anticipated monitoring projects for the next reporting year.
Following annual report submission to NMFS, the final rule language
mandates a 3-month NMFS review prior to each report being finalized.
This will provide ample time for NMFS and the Commission to comment on
the next year's planned projects as well as ongoing regional projects
or proposed new starts. Comments will be received by the Navy prior to
the annual adaptive management meeting to facilitate a meaningful and
productive discussion. NMFS and the Commission will also have the
opportunity for involvement at the annual monitoring program science
review meetings and/or regional Scientific Advisory Group meetings.
This will help NMFS and the Commission stay informed and understand the
scientific considerations and limitations involved with planning and
executing various monitoring projects.

Ongoing Navy Research

The Navy is one of the world's leading organizations in assessing
the effects of human activities on the marine environment, and provides
a significant amount of funding and support to marine research, outside
of the monitoring required by their incidental take authorizations.
They also develop approaches to ensure that these resources are
minimally impacted by current and future Navy operations. Navy
scientists work cooperatively with other government researchers and
scientists, universities, industry, and non-governmental conservation
organizations in collecting, evaluating, and modeling information on
marine resources, including working towards a better understanding of
marine mammals and sound. From 2004 to 2014, the Navy has provided over
$250 million for marine species research. The Navy sponsors 70 percent
of all U.S. research concerning the effects of human-generated sound on
marine mammals and 50 percent of such research conducted worldwide.
Major topics of Navy-supported marine species research directly
applicable to proposed activities within the MITT Study Area include
the following:
Better understanding of marine species distribution and
important habitat areas;
Developing methods to detect and monitor marine species
before, during, and after training and testing activities;
Better understanding the impacts of sound on marine
mammals, sea turtles, fish, and birds; and
Developing tools to model and estimate potential impacts
of sound.
It is imperative that the Navy's research and development (R&D)
efforts related to marine mammals are conducted in an open, transparent
manner with validated study needs and requirements. The goal of the
Navy's R&D program is to enable collection and publication of
scientifically valid research as well as development of techniques and
tools for Navy, academic, and commercial use. The two Navy
organizations that account for most funding and oversight of the Navy
marine mammal research program are the Office of Naval Research (ONR)
Marine Mammals and Biology Program, and the Office of the Chief of
Naval Operations (CNO) Energy and Environmental Readiness Division
(N45) Living Marine Resources (LMR) Program. The primary focus of these
programs has been on understanding the effects of sound on marine
mammals, including physiological, behavioral and ecological effects.
The ONR Marine Mammals and Biology Program supports basic and
applied research and technology development related to understanding
the effects of sound on marine mammals, including physiological,
behavioral, ecological, and population-level effects. Current program
thrusts include:
Monitoring and detection;
Integrated ecosystem research including sensor and tag
development;
Effects of sound on marine life including hearing,
behavioral response studies, diving and stress physiology, and
Population Consequences of Acoustic Disturbance (PCAD); and
Models and databases for environmental compliance.
To manage some of the Navy's marine mammal research programmatic
elements, OPNAV N45 developed in 2011 a Living Marine Resources (LMR)
Research and Development Program (www.lmr.namy.mil). The mission of the
LMR program is to develop, demonstrate, and assess information and
technology solutions to protect living marine resources by minimizing
the environmental risks of Navy at-sea training and testing activities
while preserving core Navy readiness capabilities. This mission is
accomplished by:
Improving knowledge of the status and trends of marine
species of concern and the ecosystems of which they are a part;
Developing the scientific basis for the criteria and
thresholds to measure the effects of Navy generated sound;
Improving understanding of underwater sound and sound
field characterization unique to assessing the biological consequences
resulting from underwater sound (as opposed to tactical applications of
underwater sound or propagation loss modeling for military
communications or tactical applications); and
Developing technologies and methods to monitor and, where
possible, mitigate biologically significant consequences to living
marine resources resulting from naval activities, emphasizing those
consequences that are most likely to be biologically significant.
The program is focused on three primary objectives that influence
program management priorities and directly affect the program's success
in accomplishing its mission:
1. Collect, Validate, and Rank R&D Needs: Expand awareness of R&D
program opportunities within the Navy marine resource community to
encourage and facilitate the submittal of well-defined and appropriate
needs statements.
2. Address High Priority Needs: Ensure that program investments and
the resulting projects maintain a direct and consistent link to the
defined user needs.
3. Transition Solutions and Validate Benefits: Maximize the number
of program-derived solutions that are successfully transitioned to the
Fleet and system commands.
The LMR program primarily invests in the following areas:
Developing Data to Support Risk Threshold Criteria;
Improved Data Collection on Protected Species, Critical
Habitat within Navy Ranges;

[[Page 46139]]

New Monitoring and Mitigation Technology Demonstrations;
Database and Model Development; and
Education and Outreach, Emergent Opportunities.
LMR currently supports the Marine Mammal Monitoring on Ranges
program at the Pacific Missile Range Facility on Kauai and, along with
ONR, the multi-year Southern California Behavioral Response Study
(https://www.socal-brs.org). This type of research helps in
understanding the marine environment and the effects that may arise
from underwater noise in oceans.

Adaptive Management

Although substantial improvements have been made in our
understanding of the effects of Navy training and testing activities
(e.g., sonar, underwater detonations) on marine mammals, the science in
this field is evolving fairly quickly. These circumstances make the
inclusion of an adaptive management component both valuable and
necessary within the context of 5-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 are appropriate. NMFS and the Navy
would meet to discuss the monitoring reports, Navy R&D developments,
and current science and whether mitigation or monitoring modifications
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 reducing adverse effects to marine mammals and if the
measures are practicable.
The following are some of the possible sources of applicable data
to be considered through the adaptive management process: (1) Results
from monitoring and exercises reports, as required by MMPA
authorizations; (2) compiled results of Navy funded R&D 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 LOA.

Reporting

In order to issue an ITA 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. NMFS described the proposed Navy
reporting requirements in the proposed rule (79 FR 15388, March 19,
2014; page 15426). 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 and
NMFS' Web site: https://www.nmfs.noaa.gov/pr/permits/incidental/. There
are several different reporting requirements that are further detailed
in the regulatory text at the end of this document and summarized
below.

General Notification of Injured or Dead Marine Mammals

Navy personnel would ensure that NMFS (the appropriate Regional
Stranding Coordinator) is notified immediately (or as soon as clearance
procedures allow) if an injured or dead marine mammal is found during
or shortly after, and in the vicinity of, any Navy training exercise
utilizing mid-frequency active sonar, high-frequency active sonar, or
underwater explosive detonations. The Navy would provide NMFS with
species identification or a description of the animal(s), the condition
of the animal(s) (including carcass condition if the animal is dead),
location, time of first discovery, observed behaviors (if alive), and
photographs or video (if available). The MITT Stranding Response Plan
contains further reporting requirements for specific circumstances
(https://www.nmfs.noaa.gov/pr/permits/incidental/).

Vessel Strike

Since the proposed rule, NMFS has added the following language to
address monitoring and reporting measures specific to vessel strike.
Most of this language comes directly from the Stranding Response Plan.
This section has also been included in the regulatory text at the end
of this document. Vessel strike during Navy training and testing
activities in the Study Area is not anticipated; however, in the event
that a Navy vessel strikes a whale, the Navy shall do the following:
Immediately report to NMFS (pursuant to the established
Communication Protocol) the:
Species identification (if known);
Location (latitude/longitude) of the animal (or location
of the strike if the animal has disappeared);
Whether the animal is alive or dead (or unknown); and
The time of the strike.
As soon as feasible, the Navy shall report to or provide to NMFS,
the:
Size, length, and description (critical if species is not
known) of animal;
An estimate of the injury status (e.g., dead, injured but
alive, injured and moving, blood or tissue observed in the water,
status unknown, disappeared, etc.);
Description of the behavior of the whale during event,
immediately after the strike, and following the strike (until the
report is made or the animal is no longer sighted);
Vessel class/type and operational status;
Vessel length;
Vessel speed and heading; and
To the best extent possible, obtain a photo or video of
the struck animal, if the animal is still in view.
Within 2 weeks of the strike, provide NMFS:
A detailed description of the specific actions of the
vessel in the 30-minute timeframe immediately preceding the strike,
during the event, and immediately after the strike (e.g., the speed and
changes in speed, the direction and changes in direction, other
maneuvers, sonar use, etc., if not classified);
A narrative description of marine mammal sightings during
the event and immediately after, and any information as to sightings
prior to the strike, if available; and use established Navy shipboard
procedures to make a camera available to attempt to capture photographs
following a ship strike.
NMFS and the Navy will coordinate to determine the services the
Navy may provide to assist NMFS with the investigation of the strike.
The response and support activities to be provided by the Navy are
dependent on resource availability, must be consistent with military
security, and must be logistically feasible without compromising Navy
personnel safety. Assistance requested and provided may vary based on
distance of strike from shore, the nature of the vessel that hit the
whale, available nearby Navy resources, operational and installation
commitments, or other factors.

[[Page 46140]]

Annual Monitoring Reports

As noted above, reports from individual monitoring events, results
of analyses, publications, and periodic progress reports for specific
monitoring projects would be posted to the Navy's Marine Species
Monitoring web portal and NMFS' Web site as they become available.
Progress and results from all monitoring activity conducted within the
MITT Study Area, as well as required Major Training Exercise activity,
would be summarized in an annual report. A draft report would be
submitted either 90 days after the calendar year or 90 days after the
conclusion of the monitoring year, date to be determined by the
adaptive management review process. In the past, each annual report has
summarized data for a single year. At the Navy's suggestion, future
annual reports would take a cumulative approach in that each report
will compare data from that year to all previous years. For example,
the third annual report will include data from the third year and
compare it to data from the first and second years. This will provide
an ongoing cumulative look at the Navy's annual monitoring and exercise
and testing reports and eliminate the need for a separate comprehensive
monitoring and exercise summary report at the end of the 5-year period.

Annual Exercise and Testing Reports

The Navy shall submit preliminary reports detailing the status of
authorized sound sources within 21 days after the anniversary of the
date of issuance of the LOA. The Navy shall submit detailed reports 3
months after the anniversary of the date of issuance of the LOA. The
detailed annual reports shall contain information on Major Training
Exercises (MTE), Sinking Exercise (SINKEX) events, and a summary of
sound sources used, as described below. The analysis in the detailed
reports will be based on the accumulation of data from the current
year's report and data collected from previous reports.

Comments and Responses

On March 19, 2014 (79 FR 15388), NMFS published a proposed rule in
response to the Navy's request to take marine mammals incidental to
training and testing activities in the MITT Study Area and requested
comments, information, and suggestions concerning the request. During
the 45-day public comment period, NMFS received comments from the
Marine Mammal Commission, private citizens, and an elected official
(Senator Vicente (ben) C. Pangelinan, 32nd Guam legislature). Comments
specific to section 101(a)(5)(A) of the MMPA and NMFS' analysis of
impacts to marine mammals are summarized, sorted into general topic
areas, and addressed below and/or throughout the final rule. Comments
specific to the MITT EIS/OEIS, which NMFS participated in developing as
a cooperating agency and adopted, or that were also submitted to the
Navy during the MITT DEIS/OEIS public comment period are addressed in
Appendix E (Public Participation) of the FEIS/OEIS. The Natural
Resources Defense Council (NRDC) did not submit comments specific to
the proposed MITT rulemaking; however, NRDC has indicated their full
endorsement of the comments and management recommendations submitted on
the MITT DEIS/OEIS by the Commonwealth of the Northern Mariana Islands
(Governor Eloy S. Inos). Those comments are addressed in Appendix E of
the FEIS/OEIS and are considered by NMFS and the Navy in the context of
both this rulemaking and related NEPA compliance. Comments submitted by
Governor Inos that are most applicable to this rulemaking include
recommended mitigation areas and are addressed below. Last, some
commenters presented technical comments on the general behavioral risk
function that are largely identical to those posed during the comment
period for proposed rules for the Hawaii Range Complex (HRC), Atlantic
Fleet Active Sonar Training (AFAST), Atlantic Fleet Training and
Testing (AFTT), and Hawaii-Southern California Training and Testing
(HSTT) study areas, predecessors to the MITT rule. The behavioral risk
function remains unchanged since then, and here we incorporate our
responses to those initial technical comments (74 FR 1455, Acoustic
Threshold for Behavioral Harassment section, page 1473; 74 FR 4844,
Behavioral Harassment Threshold section, page 4865; 78 FR 73010,
Acoustic Thresholds section, page 73038; 78 FR 78106, Acoustic
Thresholds section, page 78129). Full copies of the comment letters may
be accessed at https://www.regulations.gov.

Marine Mammal Density Estimates

Comment 1: The Commission recommended that NMFS require the Navy to
(1) account for uncertainty in extrapolated density estimates for all
species by using the upper limit of the 95% confidence interval or the
arithmetic mean plus two standard deviations and (2) then re-estimate
the numbers of takes accordingly.
Response 1: The Navy coordinated with both NMFS' Pacific Islands
Fisheries Science Center (PIFSC) and Southwest Fisheries Science Center
(SWFSC) to identify the best available density estimates for marine
mammals occurring in the Study Area. In all cases, a conservative
(i.e., greater) estimate was selected. The Navy's use of a mean density
estimate is consistent with the approach taken by NMFS to estimate and
report the populations of marine mammals in their Stock Assessment
Reports and the estimated mean is thus considered the ``best available
data.'' Adjusting the mean estimates as suggested would result in
unreasonable measures, particularly given the very high coefficient of
variation (CV) associated with most marine mammal density estimates.
Further, the Navy's acoustic model includes conservative estimates of
all parameters (e.g., assumes that the animals do not move
horizontally, assumes animals are always head-on to the sound source so
that they receive the maximum amount of energy, etc.) resulting in a
more conservative (i.e., greater) assessment of potential impacts.

Mitigation, Monitoring, and Reporting

Comment 2: Governor Eloy S. Inos (Commonwealth of the Northern
Mariana Islands [CNMI]) recommended (via comments submitted on the MITT
DEIS/OEIS) specific geographic marine mammal mitigation areas--or
habitat protection areas--to be avoided by all Navy sonar and
explosives training and testing activities. These include near-island
habitat in the vicinity of the islands of the CNMI, landward of the
3,500 m isobath (based on concentrations of insular populations of
odontocetes within the 3,500 m isobath around the Hawaiian Islands);
and from the West Mariana Ridge (a chain of conical seamounts
paralleling 145 to 170 km west of the Mariana Islands) to the 3,500 m
isobaths around the ridge, between roughly 13[deg] and 18[deg] N where
two beaked whale sightings were made during a Navy line-transect survey
in 2007, passive acoustic data acquired during that same survey showed
multiple detections of short-finned pilot whales around the ridgeline,
and satellite tagging efforts showed use of the ridge by at least one
false killer whale tagged off Rota (Hill et al., 2013).
Response 2: Under section 101(a)(5)(A) of the MMPA, NMFS must set
forth the ``means of effecting the least practical adverse impact on
such species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance.'' The
NDAA amended the

[[Page 46141]]

MMPA as it relates to military-readiness activities (which these Navy
activities are) and the incidental take authorization process such that
``least practicable adverse impact'' shall include consideration of
personnel safety, practicality of implementation, and impact on the
effectiveness of the ``military readiness activity.'' Therefore, as
discussed earlier in the Mitigation section, in making a determination
of ``least practicable adverse impact,'' NMFS considers the likely
benefits of a mitigation measures being considered to affected species
or stocks and their habitat, as well as the likely effect of those
measures on personnel safety, practicality of implementation, and the
impact on the effectiveness of the military readiness activity.
With respect to the effectiveness of area limitations, temporal
(e.g., seasonal) or geographic limitations (time/area limitations) are
a direct and effective means of reducing adverse impacts to marine
mammals. By reducing the overlap in time and space of the known
concentrations of marine mammals and the acoustic footprint associated
with the thresholds for the different types of take (either at all
times and places where animals are concentrated, or times and places
where they are concentrated for specifically important behaviors (such
as reproduction or feeding)), the amount of take can be reduced. It is
most effective when these measures are used carefully at times and
places where their effects are relatively well known. For example, if
there is credible evidence that concentrations of marine mammals are
known to be high at a specific place or during a specific time of the
year (such as the high densities of humpback whales delineated on the
Mobley map in the HRC, or North Atlantic right whale critical habitat
on the east coast), then these seasonal or geographic exclusions or
limitations may be appropriate. However, if marine mammals are known to
prefer certain types of areas (as opposed to specific areas) for
certain functions, such as beaked whale use of seamounts or marine
mammal use of productive areas like cyclonic eddies, which means that
they may or may not be present at any specific time, it is less
effective to require avoidance or limited use of the area because they
may not be present.
The Governor's recommendation that the Navy exclude sonar and
explosives training and testing in the vicinity of the islands of the
CNMI landward of the 3,500 m isobaths is based on the fact that in
Hawaii insular populations of odontocetes are generally concentrated on
important near-island habitat within the 3,500 m isobaths. However,
there is nothing to suggest that a similar isobath represents the
delineation of important near-island habitat for concentrations of
marine mammals around the islands of the CNMI. In fact, satellite tag
deployment data from cetacean (short-finned pilot whales, false killer
whales, rough-toothed dolphins, bottlenose dolphins, and melon-headed
whales) surveys in the waters surrounding Guam and the CNMI during
2010-2014, conducted by the Pacific Islands Fisheries Science Center
(PIFSC) in partnership with the Navy, showed that multiple tagged
species utilized the areas far offshore beyond the 3,500 m isobath
(Hill et al., 2014). These findings are corroborated by line transect
surveys conducted by Fulling et al. (2011), which document multiple
encounters and wide distribution of bottlenose dolphins, rough-toothed
dolphins, pantropical spotted dolphins, false killer whales, and sperm
whales far offshore of Guam and the CNMI at depths up to 9,874 m. NMFS,
therefore, does not consider the near-island waters landward of the
3,500 m isobaths around the islands of the CNMI an appropriate time/
area limitation for training and testing activities in the Study Area.
Regarding the Governor's recommendation that the Navy not conduct
sonar and explosives training and testing from the West Mariana Ridge
to the 3,500 m isobath around the ridge, the relatively limited data
cited by the Governor is not suggestive of high concentrations of
marine mammals or marine mammal species (i.e., two beaked whales, three
short-finned pilot whales, one false killer whale) specific to this
ridge. In fact, satellite tagging efforts by PIFSC indicated the vast
majority of tagged false killer whales occurred well beyond, and east
of, the West Mariana Ridge ridgeline (Hill et al., 2014 and 2015). And
while the Navy's line-transect survey and passive acoustic monitoring
conducted in 2007 noted the presence of a few individuals of short-
finned pilot whales (and beaked whales) along portions of the West
Mariana Ridge, PIFSC telemetry data analyzed by Hill et al. (2015)
indicate a preference away from the ridge and closer to the near-island
waters around Guam (though not exclusively so). NMFS recognizes the
generally biologically productive nature of some ridges and seamounts;
however, there are no data to suggest that important or species-
specific habitat (rookeries, reproductive, feeding) exists along the
West Mariana Ridge or within the 3,500 m isobath around the ridge.
In addition to NMFS' consideration of the effectiveness of the
time/area restrictions recommended by Governor Eloy S. Inos, the Navy
has provided in the MITT FEIS/OEIS the following specific reasons
explaining why these types of geographic restrictions or limitations
are considered impracticable for the Navy:
Broad Coastal Restrictions (e.g., around entire islands)
Based on Distances from Isobaths or Shorelines--Avoiding locations for
training and testing activities within the Study Area based on wide-
scale distances from isobaths or the shoreline for the purpose of
mitigation would be impractical with regard to implementation of
military readiness activities, result in unacceptable impact on
readiness, and would not be an effective means of mitigation, and would
increase safety risks to personnel. Training in shallower water is an
essential component to maintaining military readiness. Sound propagates
differently in shallower water and operators must learn to train in
this environment. Additionally, submarines have become quieter through
the use of improved technology and have learned to hide in the higher
ambient noise levels of the shallow waters of coastal environments. In
real world events, it is highly likely Sailors would be working in, and
therefore must train in, these types of areas. The littoral waterspace
is also the most challenging area to operate in due to a diverse
acoustic environment. It is not realistic or practicable to refrain
from training in the areas that are the most challenging and
operationally important. Operating in shallow water is essential in
order to provide realistic training on real world combat conditions
with regard to shallow water sound propagation.
Avoiding Locations Based on Bathymetry--Requiring training
and testing to avoid large areas that encompass a large portion of a
particular bathymetric conditions (e.g., high-relief seamounts such as
those that comprise the West Mariana Ridge) within a designated Range
Complex or study area for the purpose of mitigation would increase
safety risks to personnel and result in unacceptable impact on
readiness. Limiting training and testing (including the use of sonar
and other active acoustic sources or explosives) to avoid steep or
complex bathymetric features (e.g., seamounts) would reduce the realism
of the military readiness activity. Systems must be tested in a variety
of bathymetric conditions to ensure functionality and accuracy in a
variety of environments. Sonar operators need to train as they would

[[Page 46142]]

operate during real world combat situations. Because real world combat
situations include diverse bathymetric conditions, Sailors must be
trained to handle bottom bounce, sound passing through changing
currents, eddies, or across changes in ocean temperature, pressure, or
salinity. Training with reduced realism would alter Sailors' abilities
to effectively operate in a real world combat situation, thereby
resulting in an unacceptable increased risk to personnel safety and the
sonar operator's ability to achieve mission success.
A more detailed discussion can be found in Section 5.3.4.1 of the
MITT FEIS/OEIS.
In conclusion, NMFS has considered the time/area restrictions
recommended by Governor Eloy S. Inos and has determined that requiring
those measures would not reduce adverse effects to marine mammal
populations or stocks or provide additional protection of marine mammal
populations or stocks in the Study Area beyond those mitigation
measures already proposed in the MITT EIS/OEIS and in this final rule
(see Mitigation section above). Further, NMFS has considered the Navy's
conclusion that such limitations would impose an increased safety risk
to personnel, an unacceptable impact on the effectiveness of training
and testing activities that would affect military readiness, and an
impractical burden with regard to implementation (This process is
further detailed in Section 5.2.3 of the MITT FEIS/OEIS).
Comment 3: Senator Vicente (ben) C. Pangelinan (32nd Guam
Legislature) expressed concerns with the effectiveness of the
mitigation measures (e.g., Lookouts) outlined in the proposed rule. The
Senator also questioned whether or not animals exposed to Navy sound
sources will return to their usual locations.
Response 3: NMFS has carefully evaluated the Navy's proposed suite
of mitigation measures and considered a broad range of other measures
(including those recommended during the proposed rule public comment
period) in the context of ensuring that NMFS prescribes the means of
effecting the least practicable adverse impact on the affected marine
mammal species and stocks and their habitat. Based on our evaluation of
the Navy's proposed measures, as well as other measures considered by
NMFS or recommended by the public, NMFS has determined that the Navy's
proposed mitigation measures (especially when the adaptive management
component is taken into consideration (see Adaptive Management,
below)), along with the additions detailed in the Mitigation section
above, are adequate means of effecting the least practicable adverse
impacts on marine mammals species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, while also considering personnel safety, practicality of
implementation, and impact on the effectiveness of the military
readiness activity.
Regarding Navy Lookouts, Lookouts are a vital aspect of the
strategy for limiting potential impacts from Navy activities. Lookouts
are qualified and experienced observers of the marine environment. All
Lookouts take part in Marine Species Awareness Training so that they
are better prepared to spot marine mammals. Detailed information on the
Navy's Marine Species Awareness Training program, which speaks to
qualifications and training, is also provided in Chapter 5 of the MITT
FEIS/OEIS. Their primary duty is to detect objects in the water,
estimate the distance from the ship, and identify them as any number of
inanimate or animate objects that are significant to a Navy activity or
as a marine mammal so that the mitigation measure can be implemented.
Lookouts are on duty at all times, day and night, when a ship or
surfaced submarine is moving through the water. Lookouts are used
continuously, throughout the duration of activities that involve the
following: Active sonar, Improved Extended Echo Ranging (IEER)
sonobuoys, anti-swimmer grenades, positive control firing devices,
timedelay firing devices, gunnery exercises (surface target), missile
exercises (surface target), bombing exercises, torpedo (explosive)
testing, sinking exercises, at-sea explosives testing, vessels
underway, towed in-water devices (from manned platforms), and non-
explosive practice munitions. Visual detections of marine mammals would
be communicated immediately to a watch station for information
disseminations and appropriate mitigation action. The Navy will use
passive acoustic monitoring to supplement visual observations by
Lookouts during IEER sonobuoy activities, explosive sonobuoys using
0.6-2.5 pound (lb) net explosive weight, torpedo (explosive) testing,
and sinking exercises, to detect marine mammal vocalizations. Passive
acoustic detections will be reported to Lookouts to increase vigilance
of the visual observation. NMFS has carefully considered Navy's use of
Lookouts and determined that in combination with the Stranding Response
Plans, and the other mitigation measures identified, the Navy's
mitigation plan will effect the least practicable adverse impacts on
marine mammal species or stocks and their habitat.
There are numerous studies which document the return of marine
mammals (both odontocetes and mysticetes) following displacement of an
individual (i.e., short-term avoidance) from an area as a result of the
presence of a sound (Bowles et al., 1994; Goold, 1996; 1998; Stone et
al., 2000; Morton and Symonds, 2002; Gailey et al., 2007; Claridge and
Durban 2009; Moretti et al., 2009; McCarthy et al., 2011; Tyack et al.,
2011). These studies are referenced and discussed in both the Navy's
LOA application (Chapter 6) and the proposed rule (79 FR 15403, March
19, 2014), as well as in the Analysis and Negligible Impact
Determination section of this final rule.
Comment 4: Senator Vicente (ben) C. Pangelinan (32nd Guam
Legislature) expressed concerns with the Navy's inability to mitigate
for onset of TTS during every activity. Other commenters (e.g.,
Governor Eloy S. Inos, CNMI) on the MITT DEIS/OEIS expressed similar
concerns regarding the size of recommended mitigation zones,
particularly those proposed for MF1 sonar system activities in which
the Governor recommended the Navy ``establish a wider buffer, to the
maximum extent practicable.''
Response 4: As discussed in the proposed rule (79 FR 15388, March
19, 2014), TTS is a type of Level B harassment. In the Estimated Take
of Marine Mammal section, we quantify the effects that might occur from
the specific training and testing activities that the Navy proposes in
the MITT Study Area, which includes the number of takes by Level B
harassment (behavioral harassment, acoustic masking and communication
impairment, and TTS). Through this rulemaking, NMFS has authorized the
Navy to take marine mammals by Level B harassment incidental to Navy
training and testing activities in the MITT Study Area. In order to
issue an ITA, we must set forth the ``permissible methods of taking
pursuant to such activity, and other means of effecting the least
practical adverse impact on such species or stock and its habitat,
paying particular attention to rookeries, mating grounds, and areas of
similar significance.'' We have determined that the mitigation measures
implemented under this rule effect the least practical adverse impact
on marine mammal species and stocks and their habitat.

[[Page 46143]]

The Navy developed activity-specific mitigation zones based on the
Navy's acoustic propagation model. Each recommended mitigation zone is
intended to avoid or reduce the potential for onset of the lowest level
of injury, PTS, out to the predicted maximum range. Mitigating to the
predicted maximum range to PTS consequently also mitigates to the
predicted maximum range to onset mortality (1 percent mortality), onset
slight lung injury, and onset slight gastrointestinal tract injury,
since the maximum range to effects for these criteria are shorter than
for PTS. Furthermore, in most cases, the mitigation zone actually
covers the TTS zone. In some instances, the Navy recommended mitigation
zones are larger or smaller than the predicted maximum range to PTS
based on the associated effectiveness and operational assessments
presented in Section 5.2.3 of the MITT FEIS/OEIS. NMFS worked closely
with the Navy in the development of the recommendations and carefully
considered them prior to adopting them in this final rule. The
mitigation zones contained in this final rule represent the maximum
area the Navy can effectively observe based on the platform of
observation, number of personnel that will be involved, and the number
and type of assets and resources available. As mitigation zone sizes
increase, the potential for reducing impacts decreases. For instance,
if a mitigation zone increases from 1,000 to 4,000 yd. (914 to 3,658
m), the area that must be observed increases sixteen-fold, which is not
practicable. The mitigation measures contained in this final rule
balance the need to reduce potential impacts with the Navy's ability to
provide effective observations throughout a given mitigation zone.
Implementation of mitigation zones is most effective when the zone is
appropriately sized to be realistically observed. The Navy does not
have the resources to maintain additional Lookouts or observer
platforms that would be needed to effectively observe mitigation zones
of increased size.
Comment 5: The Commission recommended that NMFS require the Navy to
provide the predicted average and maximum ranges for all impact
criteria (i.e., behavioral response, TTS, PTS, onset slight lung
injury, onset slight gastrointestinal injury, and onset mortality), for
all activities (i.e., based on the activity category and representative
source bins and include ranges for more than 1 ping), and for all
functional hearing groups of marine mammals within MITT representative
environments (including shallow-water nearshore areas).
Response 5: The Navy discusses range to effects in Sections
3.4.4.1.1 and 3.4.4.2.1 of the MITT FEIS/OEIS. The active acoustic
tables in Section 3.4.4.1.1 illustrate the ranges to PTS, TTS, and
behavioral response. The active acoustic tables for PTS and TTS show
ranges for all functional hearing groups and the tables for behavioral
response show ranges for low-, mid-, and high-frequency cetaceans. The
active acoustic source class bins used to assess range to effects
represent some of the most powerful sonar sources and are often the
dominant source in an activity. The explosives table in Section
3.4.4.2.1 illustrates the range to effects for onset mortality, onset
slight lung injury, onset slight gastrointestinal tract injury, PTS,
TTS, and behavioral response. The explosives table shows ranges for all
functional hearing groups. The source class bins used for explosives
range from the smallest to largest amount of net explosive weight.
These ranges represent conservative estimates (i.e., longer ranges)
based on the assumption that all impulses are 1-second in duration. In
fact, most impulses are much shorter and contain less energy.
Therefore, these ranges provide realistic maximum distances over which
the specific effects would be possible.
NMFS believes that these representative sources provide adequate
information to analyze potential effects on marine mammals. Because the
Navy conducts training and testing in a variety of environments having
variable acoustic propagation conditions, variations in acoustic
propagation conditions are considered in the Navy's acoustic modeling
and the quantitative analysis of acoustic impacts.
Average ranges to effect are provided in the MITT FEIS/OEIS to show
the reader typical zones of impact around representative sources. As
noted in the LOA application and MITT FEIS/OEIS, the ranges provided in
the analysis sections (Section 6 of the LOA and Chapter 3 of the MITT
FEIS/OEIS) are the average range to all effects for representative
sources in a variety of environments (shallow and deep water). These
are not nominal values for deep-water environments, as repeatedly
asserted by the Commission.
Comment 6: The Commission recommended that NMFS require the Navy to
use passive and active acoustics to supplement visual monitoring during
implementation of mitigation measures for all activities that could
cause Level A harassment or mortality beyond those explosive activities
for which passive acoustic monitoring was already proposed.
Specifically, the Commission questioned why passive and active acoustic
monitoring used during the Navy's Surveillance Towed Array Sensory
System Low Frequency Active (SURTASS LFA) activities is not applied
here.
Response 6: The Navy requested Level A (injury) take of marine
mammals for impulse and non-impulse sources during training and testing
based on its acoustic analysis. While it is impractical for the Navy to
conduct passive acoustic monitoring during all training and testing
activities (due to lack of resources), the Navy has engineered the use
of passive acoustic detection for monitoring purposes, taking into
consideration where the largest impacts could potentially occur, and
the effectiveness and practicability of installing or using these
devices. The Navy will use passive acoustic monitoring to supplement
visual observations during Improved Extended Echo Ranging (IEER)
sonobuoy activities, explosive sonobuoys using 0.6-2.5 pound (lb) net
explosive weight, torpedo (explosive) testing, and sinking exercises,
to detect marine mammal vocalizations. However, it is important to note
that passive acoustic detections do not provide range or bearing to
detected animals, and therefore cannot provide locations of these
animals. Passive acoustic detections will be reported to lookouts to
increase vigilance of the visual observation.
The active sonar system used by SURTASS LFA is unique to the
platforms that use SURTASS LFA. Moreover, this system requires the
platforms that carry SURTASS LFA to travel at very slow speeds for the
system to be effective. For both of these reasons it is not possible
for the Navy to use this system for the platforms analyzed in the MITT
FEIS/OEIS.
NMFS believes that the Navy's suite of mitigation measures (which
include mitigation zones that exceed or meet the predicted maximum
distance to PTS) will typically ensure that animals will not be exposed
to injurious levels of sound. To date, the monitoring reports submitted
by the Navy for MIRC (or the AFTT and HSTT Study Areas), do not show
any evidence of injured marine mammals.
Comment 7: The Commission recommended that NMFS require the Navy to
use a second clearance category of 60 minutes for deep-diving species
(i.e., beaked whales and sperm whales) if the animal has not been
observed exiting the mitigation zone following shutdown of acoustic
activities due to a marine mammal sighting.

[[Page 46144]]

Response 7: NMFS does not concur with the Commission's
recommendation that the Navy should use a second clearance category of
60 minutes for deep-diving species for the following reasons:
As described in the MITT FEIS/OEIS in Chapter 5 (Standard
Operating Procedures, Mitigation, and Monitoring), a 30-minute wait
period more than covers the average dive times of most marine mammals.
The ability of an animal to dive longer than 30 minutes
does not mean that it will always do so. Therefore, the 60-minute delay
would only potentially add value in instances when animals had remained
under water for more than 30 minutes.
Navy vessels typically move at 10-12 knots (5-6 m/sec)
when operating active sonar and potentially much faster when not. Fish
et al. (2006) measured speeds of seven species of odontocetes and found
that they ranged from 1.4-7.30 m/sec. Even if a vessel was moving at
the slower typical speed associated with active sonar use, an animal
would need to be swimming near sustained maximum speed for an hour in
the direction of the vessel's course to stay within the safety zone of
the vessel. Increasing the typical speed associated with active sonar
use would further narrow the circumstances in which the 60-minute delay
would add value.
Additionally, the times when marine mammals are deep-
diving (i.e., the times when they are under the water for longer
periods of time) are the same times that a large portion of their
motion is in the vertical direction, which means that they are far less
likely to keep pace with a horizontally moving vessel.
Given that, the animal would need to have stayed in the
immediate vicinity of the sound source for an hour, and considering the
maximum area that both the vessel and the animal could cover in an
hour, it is improbable that this would randomly occur. Moreover,
considering that many animals have been shown to avoid both acoustic
sources and ships without acoustic sources, it is improbable that a
deep-diving cetacean (as opposed to a dolphin that might bow ride)
would choose to remain in the immediate vicinity of the source.
In summary, NMFS believes that it is unlikely that a single
cetacean would remain in the safety zone of a Navy sound source for
more than 30 minutes, and therefore disagrees with the Commission that
a second clearance category of 60 minutes for deep-diving species is
necessary.
Comment 8: The Commission recommended that NMFS require the Navy to
(1) provide the range to effects for all impact criteria (i.e.,
behavioral response, TTS, PTS, onset slight lung injury, onset slight
gastrointestinal injury, and onset mortality) for underwater
detonations that involve time-delay firing devices based on sound
propagation in shallow-water nearshore environments for the associated
marine mammal functional hearing groups and (2) use those data coupled
with the maximum charge weight and average swim speed of the fastest
group of marine mammals as the basis for the mitigation zone for
underwater detonations that involve time-delay firing devices. If NMFS
does not require the Navy to adjust its mitigation zones, then it
should authorize the numbers of takes for Level A harassment and
mortality based on the possibility that marine mammals could be present
in the mitigation zone when the explosives detonate and based on
updated, more realistic swim speeds.
Response 8: As shown in the LOA application (Table 11-1) and MITT
FEIS/OEIS (Table 5.3-2), which provide ranges to effects for explosive
sources used in the MITT Study Area, the maximum range to PTS effects
for a 20 lb. NEW charge used with this activity is 102 yd. (93 m), and
the average range to TTS effects is 407 yd. (372 m). A 20 lb. NEW
charge is the largest used in Mine Neutralization Activities Using
Diver-Placed Time-Delay Firing Devices. These ranges to effects for
explosive sources represent conservative estimates assuming all
impulses (i.e., explosions) are 1 second in duration. In fact, most
impulses from explosions are much less than 1 second in duration and
therefore contain much less energy than the amount of energy used to
produce the estimated ranges to effects.
The proposed mitigation zone of 1,000 yd. (914 m) is well beyond
the estimated range to effects and is overprotective for mine
neutralization activities using diver-placed time-delay firing devices.
The ranges to onset mortality, onset slight lung injury, and onset
gastrointestinal injury are all less than the range to PTS level
effects and would be well within the mitigation zone. As described in
Chapter 5, Section 5.3.1.2.2.5 (Mine Neutralization Activities Using
Diver-Placed Time-Delay Firing Devices) of the MITT FEIS/OEIS, four
Lookouts and two small boats represent the maximum level of effort that
the Navy can commit for observing the mitigation zone for this activity
given the number of personnel and assets available. In addition to the
four lookouts, divers and aircrew (if aircraft are involved in the
activity) would also serve as lookouts in addition to conducting their
regular duties to support the activity. As noted by Navy in previous
responses to comments on other Navy training and testing EIS/OEISs, the
mitigation zone is sufficiently large to account for a portion of the
distance that a marine mammal could potentially travel during the time
delay based on a reasonable assumption of marine mammal swim speeds.
The supplemental information presented by the Commission to support
the comment points out that Table 6-12 in the LOA application does not
present ranges to effects for Bin E6 (up to a 20 lb. NEW). As stated in
the table heading, the table is intended to be representative and is
not specific to the MITT Study Area; therefore not all bins are
included. However, the table shows that the proposed mitigation zone of
1,000 yd. (914 m) would also be protective against injury exposures
from explosives in Bin E7 (21 lb. to 60 lb. NEW).
Furthermore, as a result of essential fish habitat consultations
with NMFS, the Navy has agreed to maintain the maximum NEW charge used
at the Outer Apra Harbor Underwater Detonation Site at 10 lb. NEW and
not to increase the maximum NEW to 20 lb., as proposed under
Alternatives 1 and 2 of the FEIS/OEIS and in the Navy's LOA
application. A maximum charge of 20 lb. NEW is still proposed for use
at the Agat Bay Mine Neutralization Site, which is farther from shore
and in deeper water. The maximum charge at the Piti Floating Mine
Neutralization Site will also remain at 10 lb. NEW.
Comment 9: The Commission recommended that NMFS require the Navy to
submit a proposed monitoring plan for the MITT Study Area for public
review and comment prior to issuance of final regulations.
Response 9: NMFS provided an overview of the Navy's Integrated
Comprehensive Monitoring Program (ICMP) in the proposed rule (79 FR
15388, March 19, 2014). While the ICMP does not specify actual
monitoring field work or projects, it does establish top level goals
that have been developed by the Navy and NMFS. As explained in the
proposed rule, detailed and specific studies will be developed as the
ICMP is implemented and funding is allocated.
Since the proposed rule was published, the Navy has provided a more
detailed short-term plan for the first year of the rule. Monitoring in
2015 will be a combination of previously funded FY-14 ``carry-over''
projects from Phase I and new FY-15 project starts under the vision for
Phase II monitoring. A more detailed description of the Navy's planned
projects starting

[[Page 46145]]

in 2015 (and some continuing from previous years) are available on
NMFS' Web site (www.nmfs.noaa.gov/pr/permits/incidental/).
Additionally, NMFS will provide one public comment period on the
Navy's monitoring program during the 5-year regulations. At this time,
the public will have an opportunity (likely in the second year) to
comment specifically on the Navy's MITT monitoring projects and data
collection to date, as well as planned projects for the remainder of
the regulations. The public also has the opportunity to review the
Navy's monitoring reports, which are posted and available for download
every year from the Navy's marine species monitoring Web site: https://www.navymarinespeciesmonitoring.us/. Details of already funded MITT
monitoring projects and new start projects are available through the
Navy's marine species monitoring Web site: https://www.navymarinespeciesmonitoring.us/. The Navy will update the status of
their monitoring projects through the marine species monitoring site,
which serves as a public portal for information regarding all aspects
of the Navy's monitoring program, including background and guidance
documents, access to reports, and specific information on current
monitoring projects.
Through the adaptive management process (including annual
meetings), the Navy will coordinate with NMFS and the Commission to
review and revise, if required, the list of intermediate scientific
objectives that are used to guide development of individual monitoring
projects. As described previously in the Monitoring section of this
document, NMFS and the Commission will also have the opportunity to
attend annual monitoring program science review meetings and/or
regional Scientific Advisory Group meetings.
The Navy will continue to submit annual monitoring reports to NMFS,
which describe the results of the adaptive management process and
summarize the Navy's anticipated monitoring projects for the next
reporting year. NMFS will have a three-month review period to comment
on the next year's planned projects, ongoing regional projects, and
proposed new project starts. NMFS' comments will be submitted to the
Navy prior to the annual adaptive management meeting to facilitate a
meaningful and productive discussion between NMFS, the Navy, and the
Commission.

Effects Analysis/Takes

Comment 10: The Commission recommended that NMFS authorize the
total numbers of model-estimated Level A harassment and mortality takes
rather than allowing the Navy to reduce the estimated numbers of Level
A harassment and mortality takes based on the Navy's proposed post-
model analysis.
Response 10: NMFS believes that the post-modeling analysis is an
effective method for quantifying the implementation of mitigation
measures to reduce impacts on marine mammals, and that the resulting
exposure estimates are, nevertheless, a conservative estimate of
impacts on marine mammals.
See Section 3.4.3.2 (Marine Mammal Avoidance of Sound Exposures) as
presented in the MITT FEIS/OEIS for the discussion of the science
regarding the avoidance of sound sources by marine mammals. In
addition, the Technical Report, Post-Model Quantitative Analysis of
Animal Avoidance Behavior and Mitigation Effectiveness for the Mariana
Islands Training and Testing (https://www.mitt-eis.com), goes into
detail on how the avoidance and mitigation factors were used and
provides scientific support from peer-reviewed research. The Navy
analysis does not indicate nor is it expected that marine mammals would
abandon important habitat on a long-term or even permanent basis. As
presented in Section 3.4.5.2 (Summary of Observations During Previous
Navy Activities) of the MITT FEIS/OEIS, the information gathered to
date including research, monitoring before, during, and after training
and testing events across the Navy since 2006, has resulted in the
assessment that it is unlikely there will be impacts on populations of
marine mammals (such as whales, dolphins and porpoise) having any long-
term consequences as a result of the proposed continuation of training
and testing in the ocean areas historically used by the Navy including
the Study Area.
As part of the post-modeling analysis, the Navy reduced some
predicted PTS exposures and mortality based on the potential for marine
mammals to be detected and mitigation implemented. Given this
potential, not taking into account some possible reduction in Level A
exposures and mortality would result in a less realistic,
overestimation of possible Level A and mortality takes, as if there
were no mitigation measures implemented. The period of time between
clearing the impact area of any non-participants or marine mammals and
weapons release is on the order of minutes, making it highly unlikely
that a marine mammal would enter the mitigation zone.
The assignment of mitigation effectiveness scores and the
appropriateness of consideration of sightability using detection
probability, g(O), when assessing the mitigation in the quantitative
analysis of acoustic impacts is discussed in the MITI FEIS/OEIS
(Section 3.4.3.3, Implementing Mitigation to Reduce Sound Exposures).
Additionally, the activity category, mitigation zone size, and number
of Lookouts are provided in the proposed rule (FR 79 15388) and MITT
FEIS/OEIS (Section 5, Tables 5.3-2 and 5.4-1). In addition to the
information already contained within the MITT FEIS/OEIS, the Post-Model
Quantitative Analysis of Animal Avoidance Behavior and Mitigation
Effectiveness for the Mariana Islands Training and Testing Technical
Report (https://www.mitt-eis.com) describes the process for the post-
modeling analysis in further detail. There is also information on
visual detection leading to the implementation of mitigation in the
annual exercise reports provided to NMFS and briefed annually to NMFS
and the Commission. These annual exercise reports have been made
available and can be found at https://www.navymarinespeciesmonitoring.us/ in addition to https://www.nmfs.noaa/pr/permits/incidental.
In summary, NMFS and the Navy believe consideration of marine
mammal sightability and activity-specific mitigation effectiveness is
appropriate in the Navy's quantitative analysis in order to provide
decision makers a reasonable assessment of potential impacts under each
alternative. A comprehensive discussion of the Navy's quantitative
analysis of acoustic impacts, including the post-model analysis to
account for mitigation and avoidance, is presented in Chapter 6 of the
LOA application.
Comment 11: The Commission recommended that NMFS require the Navy
to round its takes, based on those takes in the MITT FEIS/OEIS Criteria
and Thresholds Technical Report tables, to the nearest whole number or
zero in all of its take tables and then authorize those numbers of
takes.
Response 11: The exposure numbers presented in the MITT FEIS/OEIS
Criteria and Thresholds Technical Report are raw model output that have
not been adjusted by post-processing to account for likely marine
mammal behavior or the effect from implementation of mitigation
measures. All fractional post-processed exposures for a species across
all events within

[[Page 46146]]

each category subtotal (Training, Testing, Impulse, and Non-Impulse)
are summed to provide an annual total predicted number of effects. The
final exposure numbers presented in the LOA application and the MITT
FEIS/OEIS incorporate post-processed exposures numbers that have been
rounded down to the nearest integer so that subtotals correctly sum to
total annual effects rather than exceed the already overly conservative
total exposure numbers.
Comment 12: Senator Vicente (ben) C. Pangelinan (32nd Guam
Legislature) expressed concerns with the purported lack of data or
supporting studies in the proposed rule on how anthropogenic sound will
affect reproduction and survival of marine mammals in the Study Area.
The Senator cites studies by Claridge (2013) and others (e.g.,
International Whaling Commission, 2005) that suggest stressors
associated with Navy sonar use and impulse sound may lead to strandings
and lower reproductive rates in some species. The Senator also points
out that several authors have established that long-term and intense
disturbance stimuli can cause population declines in some (terrestrial)
species.
Response 12: NMFS fully considers impacts to recruitment and
survival (population-level effects) when making a negligible impact
determination and when prescribing the means of effecting the least
practicable impact on species and stocks. NMFS is constantly evaluating
new science and how to best incorporate it into our decisions. This
process involves careful consideration of new data and how it is best
interpreted within the context of a given management framework. Recent
studies have been published regarding behavioral responses that are
relevant to the proposed activities and energy sources: Moore and
Barlow, 2013; DeRuiter et al., 2013; and Goldbogen et al., 2013, among
others. Each of these articles emphasizes 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. In addition, New et al., 2013 and 2014; Houser et al., 2013;
and Claridge, 2013 were recently published. These and other relevant
studies are discussed in both the Potential Effects of Specified
Activities on Marine Mammals section and the Analysis and Negligible
Impact Determination section of this final rule.
The Analysis and Negligible Impact Determination section of this
final rule includes a species or group-specific analysis (see Group and
Species-Specific Analysis) of potential effects on marine mammal in the
Study Area, as well as a discussion on long-term consequences (see
Long-Term Consequences) for individuals or populations resulting from
Navy training and testing activities in the Study Area. As discussed
later in this document, populations of beaked whales and other
odontocetes in the Bahamas, and in other Navy fixed ranges that have
been operating for tens of years, appear to be stable. Range complexes
where intensive training and testing have been occurring for decades
have populations of multiple species with strong site fidelity
(including highly sensitive resident beaked whales at some locations)
and increases in the number of some species.
There is no direct evidence that routine Navy training and testing
spanning decades has negatively impacted marine mammal populations at
any Navy range complex. In at least three decades of similar
activities, only one instance of injury to marine mammals (March 4,
2011; three long-beaked common dolphin) has been documented as a result
of training or testing using an impulse source (underwater explosion).
Years of monitoring of Navy-wide activities (since 2006) have
documented hundreds of thousands of marine mammals on the range
complexes and there are only two instances of overt behavioral change
that have been observed. Years of monitoring of Navy-wide activities on
the range complexes have documented no demonstrable instances of injury
to marine mammals as a direct result of non-impulsive acoustic sources.
Stranding events coincident with Navy MFAS use in which exposure to
sonar is believed to have been a contributing factor were detailed in
the Stranding and Mortality section of the proposed rule. However, for
some of these stranding events, a causal relationship between sonar
exposure and the stranding could not be clearly established (Cox et
al., 2006). In other instances, sonar was considered only one of
several factors that, in their aggregate, may have contributed to the
stranding event (Freitas, 2004; Cox et al., 2006). NMFS and the Navy
have identified certain circumstances/factors (including 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 sonars)
that have been present in some instances where strandings are
associated with active Navy sonar (e.g., Bahamas, 2000). 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. In
addition, the Navy has developed specific planning and monitoring
measures to use when that suite of factors is present. These
circumstances/factors do not exist in their aggregate in the MITT Study
Area.
Because of the association between tactical MFA 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 a suite of mitigation
intended to more broadly minimize impacts to marine mammals, the Navy
and NMFS have a detailed Stranding Response Plan that outlines
reporting, communication, and response protocols intended both to
minimize the impacts of, and enhance the analysis of, any potential
stranding in areas where the Navy operates.
Based on the best available science NMFS concludes that exposures
to marine mammal species and stocks due to MITT activities would result
in only short-term effects to most individuals exposed and are not
expected to affect annual rates of recruitment or survival (population-
level impacts having any long-term consequences). Results of the Navy's
acoustic analysis and NMFS' analysis, as well as the relevant studies
supporting this conclusion, are referenced and summarized in the
Analysis and Negligible Impact Determination section of this final
rule.

Criteria and Thresholds

Comment 13: The Commission recommended that NMFS require the Navy
to (1) use 157 rather than 152 dB re 1 [mu]Pa\2\-sec as the temporary
threshold shift (TTS) threshold for high-frequency cetaceans exposed to
acoustic sources, (2) use 169 rather than 172 dB re 1 [mu]Pa\2\-sec as
the TTS thresholds for mid- and low-frequency cetaceans exposed to
explosive sources, (3) use 145 rather than 146 dB re 1 [mu]Pa\2\-sec as
the TTS threshold for high-frequency cetaceans for explosive sources,
and (4)(a) based on these changes to the TTS thresholds, adjust the
permanent threshold shift (PTS) thresholds for high-frequency

[[Page 46147]]

cetaceans exposed to acoustic sources by increasing the amended TTS
threshold by 20 dB, and for low-, mid-, and high-frequency cetaceans
exposed to explosive sources, by increasing the amended TTS thresholds
by 15 dB and (b) adjust the behavioral thresholds for low-, mid-, and
high-frequency cetaceans exposed to explosive sources by decreasing the
amended TTS thresholds by 5 dB.
Response 13: NMFS does not concur with the Commissions'
recommendations for similar reasons to those provided in prior
responses to Comission comments on the HSTT and AFTT proposed
rulemakings. The values derived for impulsive and non-impulsive TTS are
based on data from peer-reviewed scientific studies. The development of
these thresholds and criteria is detailed in the Criteria and
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis
Technical Report (Finneran and Jenkins, 2012) that is referenced in the
MITT FEIS/OEIS (see Section 3.4.3.1.4 [Thresholds and Criteria for
Predicting Acoustic and Explosive Impacts on marine mammals]) and
available at https://www.mitt-eis.com.
As presented in Finneran and Jenkins (2012) the thresholds
incorporate new findings since the publication of Southall et al.
(2007) and the evolution of scientific understanding since that time.
Note that Dr. Finneran was one of the authors for Southall et al.
(2007) and so is completely familiar with the older conclusions
presented in the 2007 publication and, therefore, was able to integrate
knowledge into development of the refined approach presented in
Finneran and Jenkins (2012) based on evolving science since 2007.
Briefly, the original experimental data is weighted using the
prescribed weighting function to determine the numerical threshold
value. The Commission did not consider the appropriate weighting
schemes when comparing thresholds presented in Southall et al. (2007)
and those presented in Finneran and Jenkins (2012). TTS thresholds
presented in Finneran and Jenkins (2012) are appropriate when the
applicable weighting function (Type II) is applied to the original TTS
data; TTS thresholds in Southall et al. (2007) were based on M-
weighting.
For example, while it is true that there is an unweighted 12-dB
difference for onset-TTS between beluga watergun (Finneran et al.,
2002) and tonal exposures (Schlundt et al., 2000), the difference after
weighting with the Type II MF-cet weighting function (from Finneran and
Jenkins, 2012), is 6-dB. The Commission has confused (a) the 6 dB
difference in PTS and TTS thresholds based on peak pressure described
in Southall et al. 2007 with (b) the difference between impulsive and
non-impulsive thresholds in Finneran and Jenkins (2012), which is
coincidentally 6 dB.
The same offset between impulsive and non-impulsive temporary
threshold shift, for the only species where both types of sound were
tested (beluga), was used to convert the Kastak et al. (2005) data
(which used non-impulsive tones) to an impulsive threshold. This method
is explained in Finneran and Jenkins (2012) and Southall et al. (2007).
The thresholds and criteria used in the MITT analysis have already
incorporated the correct balance of conservative assumptions that tend
towards overestimation in the face of uncertainty. Additional details
regarding the process are provided in Section 3.4.3.1.5 (Quantitative
Analysis) of the MITT FEIS/OEIS. In addition, the summary of the
thresholds used in the analysis are presented in Section 3.4.3.1.4
(Thresholds and Criteria for Predicting Acoustic and Explosive Impacts
on Marine Mammals) of the MITT FEIS/OEIS. NMFS was included in the
development of the current thresholds. The thresholds used in the
current analysis remain the best available estimate of the number and
type of take that may result from the Navy's use of acoustic sources in
the MITT Study Area, although NMFS and the Navy will continue to revise
those thresholds based on emergent research.
Comment 14: The Commission recommended that NMFS require the Navy
to (1) describe what it used as the upper limit of behavioral response
function for low-frequency cetaceans (BRF1) and the upper
limits of BRF2 for both mid- and high-frequency cetaceans,
including if it assumed a 1-sec ping for all sources and (2) if the
upper limits of the BRFs were based on weighted thresholds, use the
unweighted or M-weighted thresholds of 195 dB re 1 [mu]Pa\2\-sec for
low- and mid-frequency cetaceans and 176 dB re 1 [mu]Pa\2\-sec for
high-frequency cetaceans to revise its behavior take estimates for all
marine mammals exposed to acoustic sources.
Response 14: The behavioral response functions (BRFs) used to
define criteria for assessing behavioral responses to underwater sound
sources are discussed in Section 3.4.3.1.4 (Thresholds and Criteria for
Predicting Acoustic and Explosive Impacts on Marine Mammals) of the
FEIS/OEIS and in the Technical Report, Criteria and Thresholds for U.S.
Navy Acoustic and Explosive Effects Analysis (Finneran and Jenkins,
2012). The BRFs have been used by the Navy to assess behavioral
reactions in marine mammals for several years and are described in
greater detail in the Atlantic Fleet Active Sonar Training EIS/OEIS
(see Section 4.4.5.3.2 Development of the Risk Function), as well as in
the Southern California Range Complex EIS/OEIS and the Hawaii Range
Complex EIS/OEIS.
Harassment under the BRF and harassment under the TTS criteria are
both considered Level B takes under MMPA, and NMFS has determined that
animals whose exposure both exceeds TTS threshold and results in
behavioral response under the BRF should not be double counted or
counted as taken twice by the same acoustic exposure. Although
behavioral responses (non-TTS) and TTS are both considered as Level B
under the MMPA for military readiness, they are two separate criteria
based on different metrics and different frequency weighting systems.
Sound exposure level (SEL) is the most appropriate metric to predict
TTS, because it accounts for signal duration. Sound pressure level
(SPL) is independent of signal duration and is the metric that best
correlates with potential behavioral response. Furthermore, to predict
TTS, SEL is weighted with a Type II function for cetaceans, whereas to
predict a behavioral response, SPL is weighted with a Type I function.
Mathematically, SEL (for TTS) and SPL (for behavior) are not on the
same linear scale, and their relationship to one another changes based
on the frequency and duration of the sounds being analyzed.
Based on the model-estimated exposure results, an animat (virtual
representation of an animal) exposed to sound that exceeds both the TTS
(SEL) threshold and Behavioral (SPL) threshold is reported as a TTS
(higher level) effect. It is important to note that TTS is a step
function, so 100 percent of animals predicted to equal or surpass the
TTS threshold would be counted as TTS effects. Behavioral effects are
estimated as the percentage of animals (i.e. between 0 and 100 percent)
that may be affected based on the highest received SPL on a BRF.

Vessel Strikes

Comment 15: The Commission recommended that NMFS require the Navy
to use its spatially and temporally dynamic simulation models rather
than simple probability calculations to estimate strike probabilities
for specific activities (i.e., movement of vessels, torpedoes, unmanned
underwater vehicles and use of expended

[[Page 46148]]

munitions, ordnance, and other devices).
Response 15: The Navy considered using a dynamic simulation model
to estimate strike probability. However, the Navy determined, and NMFS
concurs, that the use of historical data was a more appropriate way to
analyze the potential for strike. The Navy's strike probability
analysis in the MITT FEIS/OEIS is based upon actual data collected from
historical use of vessels, in-water devices, and military expended
materials, and the likelihood that these items may have the potential
to strike an animal. This data accounts for real world variables over
the course of many years, and any model would be expected to be less
accurate than the use of actual data. There is no available science
regarding the necessary functional parameters for a complex dynamic
whale strike simulation model; there are large unknowns regarding the
data that would be necessary such as the density, age classes, and
behavior of large whales in the MITT Study Area; and there are no means
to validate the output of a model given there is no empirical data (not
strikes) to ``seed the dynamic simulation.'' Therefore, use of
historical data from identical activities elsewhere and additional use
of a probability analysis remain a more reasonable analytical approach.
The Commission's disagreement over the method the Navy has used to
estimate strike probability is noted. Any increase in vessel movement,
as discussed in Section 3.4.4.4.1 (Impacts from Vessels) of the MITT
FEIS/OEIS, over the No Action is still well below areas such as the
Southern California Range Complex (SOCAL) where the density of large
whales and the number of Navy Activities is much higher than any of the
MITT alternatives and yet strikes to large whales are still relatively
rare in SOCAL. Additionally, while the number of training and testing
activities is likely to increase, it is not expected to result in an
appreciable increase in vessel use or transits since multiple
activities usually occur from the same vessel. The Navy is not
proposing substantive changes in the locations where vessels have been
used over the last decade.
There has never been a vessel strike to a whale during any active
training or testing activities in the Study Area. A detailed analysis
of strike data is also contained in Chapter 6 (Section 6.3.4, Estimated
Take of Large Whales by Navy Vessel Strike) of the LOA application. The
Navy does not anticipate vessel strikes to marine mammals during
training or testing activities within the Study Area, nor were takes by
injury or mortality resulting from vessel strike predicted in the
Navy's analysis. Therefore, NMFS is not authorizing mysticete takes (by
injury or mortality) from vessel strikes during the 5-year period of
the MITT regulations.

General Opposition

Comment 16: One commenter expressed general opposition to Navy
activities and NMFS' issuance of an MMPA authorization.
Response 16: NMFS appreciates the commenter's concern for the
marine environment. However, the MMPA directs NMFS to issue an
incidental take authorization if certain findings can be made. NMFS has
determined that the Navy's training and testing activities will have a
negligible impact on the affected species or stocks and, therefore, we
plan to issue the requested MMPA authorization.

Other

Comment 17: One commenter asked about the effects of Navy
activities on marine habitat and other resources not addressed in the
proposed rule.
Response 17: The MITT FEIS/OEIS addresses all potential impacts to
the human environment, and is available online at https://www.mitt-eis.com. The MITT DEIS/OEIS was made available to the public on
September 13, 2013 and was referenced in the proposed rule (79 FR
15388, March 19, 2014).
Comment 18: One commenter requested additional details or
elaboration regarding specific Navy training and testing activities
(e.g., vessel type and speed, inwater detonations, Pierside Location
maintenance, etc.).
Response 18: Detailed information about each proposed activity
(stressor, training or testing event, description, sound source,
duration, and gepgraphic location) can be found in the MITT FEIS/OEIS.
Comment 19: One commenter had several questions regarding
information (e.g., species presence, distribution, stock abundance,
ESA/MMPA status) presented in Table 6 (Marine Mammals with Possible or
Confirmed Presence within the Study Area) and the Description of Marine
Mammals in the Area of the Specified Activity section of the proposed
rule.
Response 19: As stated in the proposed rule, information on the
status, occurrence and distribution, abundance, derivation of density
estimates, and vocalizations of marine mammal species in the Study Area
may be viewed in Chapters 3 and 4 of the LOA application (https://www.nmfs.noaa.gov/pr/permits/incidental/). This information was
compiled by the Navy from peer-reviewed literature, NMFS annual stock
assessment reports (SARs) for marine mammals (https://www.nmfs.noaa.gov/pr/species/mammals; Carretta et al., 2014; Allen and Angliss, 2014),
and marine mammal surveys using acoustic and visual observations from
aircraft and ships. Further information on the general biology and
ecology of marine mammals is included in the MITT FEIS/OEIS (https://www.mitt-eis.com.).
Comment 20: One commenter questioned NMFS' proposed authorization
of take through issuance of a single 5-year LOA (multi-year LOA) rather
than issuance of annual LOAs.
Response 20: The ability to issue a multi-year LOA reduces
administrative burdens on both NMFS and the Navy. In addition, a multi-
year LOA would avoid situations where the last minute issuance of LOAs
necessitates the commitment of extensive resources by the Navy for
contingency planning.
The regulations still: (1) Require the Navy to submit annual
monitoring and exercise reports; (2) require that NMFS and the Navy
hold annual monitoring and adaptive management meetings that ensure
NMFS is able to evaluate the Navy's compliance and marine mammal
impacts with the same attention and frequency; and (3) allow for a LOA
to be changed at any time, as appropriate, to incorporate any needed
mitigation or monitoring measures developed through adaptive
management, based on the availability of new information regarding
military readiness activities or the marine mammals affected. If,
through adaptive management, proposed modifications to the mitigation,
monitoring, or reporting measures are substantial, NMFS would publish a
notice of proposed LOA in the Federal Register and solicit public
comment.

Estimated Take

In the Estimated Take section of the proposed rule, NMFS described
the potential effects to marine mammals from active sonar and
underwater detonations in relation to the MMPA regulatory definitions
of Level A and Level B harassment (79 FR 15388, pages 15426-15430).
That information has not changed and is not repeated here. It is
important to note that, as Level B Harassment is interpreted here and
quantified by the behavioral thresholds described below, the fact that
a single behavioral pattern (of unspecified duration) is abandoned or
significantly altered and classified as a Level B take does not mean,
necessarily, that the

[[Page 46149]]

fitness of the harassed individual is affected either at all or
significantly, or that, for example, a preferred habitat area is
abandoned. Further analysis of context and duration of likely exposures
and effects is necessary to determine the impacts of the estimated
effects on individuals and how those may translate to population-level
impacts, and is included in the Analysis and Negligible Impact
Determination.
Tables 8 and 9 provide a summary of non-impulsive and impulsive
thresholds to TTS and PTS for marine mammals. A detailed explanation of
how these thresholds were derived is provided in the MITT FEIS/OEIS
Criteria and Thresholds Technical Report (https://www.mitt-eis.com) and
summarized in Chapter 6 of the Navy's LOA application (https://www.nmfs.noaa.gov/pr/permits/incidental/).

Table 8--Onset TTS and PTS Thresholds for Non-Impulse Sound
----------------------------------------------------------------------------------------------------------------
Group Species Onset TTS Onset PTS
----------------------------------------------------------------------------------------------------------------
Low-Frequency Cetaceans.............. All mysticetes......... 178 dB re 1[mu]Pa2- 198 dB re 1[mu]Pa2-
sec(LFII). sec(LFII).
Mid-Frequency Cetaceans.............. Most delphinids, beaked 178 dB re 1[mu]Pa2- 198 dB re 1[mu]Pa2-
whales, medium and sec(MFII). sec(MFII).
large toothed whales.
High-Frequency Cetaceans............. Porpoises, Kogia spp... 152 dB re 1[mu]Pa2- 172 dB re 1[mu]Pa2-
sec(HFII). secSEL (HFII).
----------------------------------------------------------------------------------------------------------------
LFII, MFII, HFII: New compound Type II weighting functions.

Table 9--Impulsive Sound Explosive Thresholds for Predicting Injury and Mortality
--------------------------------------------------------------------------------------------------------------------------------------------------------
Slight Injury
Group Species ----------------------------------------------------------------------- Mortality
PTS GI Tract Lung
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency Cetaceans........... All mysticetes....... 187 dB SEL (LFII) or
230 dB Peak SPL.
Mid-frequency Cetaceans........... Most delphinids, 187 dB SEL (MFII) or 237 dB SPL............ Equation 1............ Equation 2.
medium and large 230 dB Peak SPL.
toothed whales.
High-frequency Cetaceans.......... Porpoises and Kogia 161 dB SEL (HFII) or
spp. 201 dB Peak SPL.
--------------------------------------------------------------------------------------------------------------------------------------------------------

[GRAPHIC] [TIFF OMITTED] TR03AU15.012

Where:

M = mass of the animals in kg
DRm = depth of the receiver (animal) in meters
[GRAPHIC] [TIFF OMITTED] TR03AU15.000

Where:

R = Risk (0-1.0)
L = Received level (dB re: 1 [mu]Pa)
B = Basement received level = 120 dB re: 1 [mu]Pa
K = Received level increment above B where 50-percent risk = 45 dB
re: 1 [mu]Pa
A = Risk transition sharpness parameter = 10 (odontocetes) or 8
(mysticetes)

Take Request

The MITT FEIS/OEIS considered all training and testing activities
proposed to occur in the Study Area that have the potential to result
in the MMPA defined take of marine mammals. The potential stressors
associated with these activities included the following:
Acoustic (sonar and other active acoustic sources,
explosives, weapons firing, launch and impact noise, vessel noise,
aircraft noise);
Energy (electromagnetic devices);
Physical disturbance or strikes (vessels, in-water
devices, military expended materials, seafloor devices);
Entanglement (fiber optic cables, guidance wires,
parachutes);
Ingestion (munitions, military expended materials other
than munitions);
Indirect stressors (impacts to habitat [sediment and water
quality, air quality] or prey availability).
NMFS has determined that two stressors could potentially result in
the incidental taking of marine mammals from training and testing
activities within the Study Area: (1) Non-impulse acoustic stressors
(sonar and other active acoustic sources) and (2) impulse acoustic
stressors (explosives). Non-impulse and impulse stressors have the
potential to result in incidental takes of marine mammals by Level A
(injury) or Level B (behavioral) harassment. NMFS also considered the
potential for vessel strikes to impact marine mammals, and that
assessment is presented below. Lethal takes of large whales and beaked
whales, while not anticipated or predicted in the Navy's acoustic
analysis, were originally conservatively requested by the Navy for MITT
training

[[Page 46150]]

and testing activities over the 5-year period of NMFS' final
authorization. That request was included in NMFS' proposed rule (79 FR
15388, Take Request); however, NMFS has since made the decision not to
authorize any lethal takes for MITT activities for reasons discussed
below.
Training and Testing Activities--Based on the Navy's modeling and
post-model analysis (i.e., the acoustic analysis) (described in detail
in Chapter 6 of their LOA application), Table 10 summarizes the
authorized takes for training and testing activities for an annual
maximum year (a notional 12-month period when all annual and non-annual
events could occur) and the summation over a 5-year period (annual
events occurring five times and non-annual events occurring three
times). Table 11 summarizes the authorized takes for training and
testing activities by species from the modeling estimates.
Predicted effects on marine mammals result from exposures to sonar
and other active acoustic sources and explosions during annual training
and testing activities. The acoustic analysis predicts the majority of
marine mammal species in the Study Area would not be exposed to
explosive (impulse) sources associated with training and testing
activities that would exceed the current impact thresholds.
No beaked whales are predicted in the acoustic analysis to be
exposed to sound levels associated with PTS, other injury, or
mortality. The Navy had originally conservatively requested
authorization for beaked whale mortality (no more than 10 mortalities
over 5 years) that might potentially result from exposure to active
sonar, based on the few instances where sonar has been associated with
strandings in other areas. That request was included in NMFS' proposed
rule (79 FR 15388, Take Request). However, after decades of the Navy
conducting similar activities in the MITT Study Area without incident,
neither the Navy nor NMFS expect stranding, injury, or mortality of
beaked whales to occur as a result of Navy activities, and therefore,
following consultation with the Navy, NMFS is not authorizing any Level
A (injury or mortality) takes for beaked whales. In addition to a suite
of mitigation intended to more broadly minimize impacts to marine
mammals, the Navy and NMFS have a detailed Stranding Response Plan
(described in the Mitigation section of this final rule and available
at https://www.nmfs.noaa.gov/pr/permits/incidental/) that outlines
reporting, communication, and response protocols intended both to
minimize the impacts of, and enhance the analysis of, any potential
stranding in areas where the Navy operates.
Vessel Strike--There has never been a vessel strike to a marine
mammal during any active training or testing activities in the Study
Area. A detailed analysis of strike data is contained in Chapter 6
(Section 6.3.4, Estimated Take of Large Whales by Navy Vessel Strike)
of the LOA application. There have been Navy strikes of large whales in
areas outside the Study Area, such as Hawaii and Southern California.
However, these areas differ significantly from the Study Area given
that both Hawaii and Southern California have a much higher number of
Navy vessel activities and much higher densities of large whales. The
Navy does not anticipate vessel strikes to marine mammals during
training or testing activities within the Study Area, nor were takes by
injury or mortality resulting from vessel strike predicted in the
Navy's analysis. Vessel strike to marine mammals is not associated with
any specific training or testing activity but rather a limited,
sporadic, and accidental result of Navy vessel movement. In order to
account for the accidental nature of vessel strikes to large whales in
general, and the potential risk from any vessel movement within the
MITT Study Area, the Navy had originally conservatively requested
authorization for large whale mortalities (no more than 5 mortalities
over 5 years) that might potentially result from vessel strike during
MITT training and testing activities over the 5-year period of NMFS'
final authorization. That request was included in NMFS' proposed rule
(79 FR 15388, Take Request). However, after further consideration of
the Navy's ship strike analysis, the unlikelihood of a ship strike to
occur and the fact that there has never been a ship strike to marine
mammals in the Study Area, and following consultation with the Navy,
NMFS is not authorizing takes (by injury or mortality) from vessel
strikes during the 5-year period of the MITT regulations. The Navy has
proposed measures (see Mitigation) to mitigate potential impacts to
marine mammals from vessel strikes during training and testing
activities in the Study Area.

Table 10--Summary of Authorized Annual and 5-Year Takes for Training and Testing Activities
----------------------------------------------------------------------------------------------------------------
Training and testing activities
MMPA Category Source ---------------------------------------------------
Annual authorization 1 5-Year authorization 2
----------------------------------------------------------------------------------------------------------------
Level A.......................... Impulse and Non-Impulse.. 56-Species specific data 280-Species specific
shown in Table 11. data shown in Table 11
Level B.......................... Impulse and Non-Impulse.. 81,906-Species specific 409,530-Species specific
data shown in Table 11. data shown in Table 11
----------------------------------------------------------------------------------------------------------------
\1\ These numbers constitute the total for an annual maximum year (a notional 12-month period when all annual
and non-annual events could occur).
\2\ These numbers constitute the summation over a 5-year period with annual events occurring five times and non-
annual events occurring three times.

Table 11--Authorized Species-Specific Takes From Modeling and Post-Model Estimates of Impulsive and Non-Impulsive Source Effects for All Training And
Testing Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annually 1 Total over 5-year rule 2
Species -----------------------------------------------------------------------------------------------
Level B Level A Mortality Level B Level A Mortality
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blue whale.............................................. 28 0 0 140 0 0
Fin whale............................................... 28 0 0 140 0 0
Humpback whale.......................................... 860 0 0 4,300 0 0
Sei whale............................................... 319 0 0 1,595 0 0
Sperm whale............................................. 506 0 0 2,530 0 0

[[Page 46151]]

Bryde's whale........................................... 398 0 0 1,990 0 0
Minke whale............................................. 101 0 0 505 0 0
Omura's whale........................................... 103 0 0 515 0 0
Pygmy sperm whale....................................... 5,579 15 0 27,895 75 0
Dwarf sperm whale....................................... 14,217 41 0 71,085 205 0
Killer whale............................................ 84 0 0 420 0 0
False killer whale...................................... 555 0 0 2,775 0 0
Pygmy killer whale...................................... 105 0 0 525 0 0
Short-finned pilot whale................................ 1,815 0 0 9,075 0 0
Melon-headed whale...................................... 2,085 0 0 10,425 0 0
Bottlenose dolphin...................................... 741 0 0 3,705 0 0
Pantropical spotted dolphin............................. 12,811 0 0 64,055 0 0
Striped dolphin......................................... 3,298 0 0 16,490 0 0
Spinner dolphin......................................... 589 0 0 2,945 0 0
Rough toothed dolphin................................... 1,819 0 0 9,095 0 0
Fraser's dolphin........................................ 2,572 0 0 12,860 0 0
Risso's dolphin......................................... 505 0 0 2,525 0 0
Cuvier's beaked whale................................... 22,541 0 0 112,705 0 0
Blainville's beaked whale............................... 4,426 0 0 22,130 0 0
Longman's beaked whale.................................. 1,924 0 0 9,620 0 0
Ginkgo-toothed beaked whale............................. 3,897 0 0 19,485 0 0
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ These numbers constitute the total for an annual maximum year (a notional 12-month period when all annual and non-annual events could occur).
\2\ These numbers constitute the summation over a 5-year period with annual events occurring five times and non-annual events occurring three times.

Marine Mammal Habitat

The Navy's proposed training and testing activities could
potentially affect marine mammal habitat through the introduction of
sound into the water column, impacts to the prey species of marine
mammals, bottom disturbance, or changes in water quality. Each of these
components was considered in Chapter 3 of the MITT FEIS/OEIS. Based on
the information in the Marine Mammal Habitat section of the proposed
rule (79 FR 15388, March 19, 2014; pages 15412-15414) and the
supporting information included in the MITT FEIS/OEIS, NMFS has
determined that training and testing activities would not have adverse
or long-term impacts on marine mammal habitat. In summary, expected
effects to marine mammal habitat will include elevated levels of
anthropogenic sound in the water column; short-term physical alteration
of the water column or bottom topography; brief disturbances to marine
invertebrates; localized and infrequent disturbance to fish; a limited
number of fish mortalities; and temporary marine mammal avoidance.

Analysis and Negligible Impact Determination

Negligible impact is ``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, as the
severity of harassment may vary greatly depending on the context and
duration of the behavioral response, many of which would not be
expected to have deleterious impacts on the fitness of any individuals.
In determining whether the expected takes will have a negligible
impact, in addition to considering estimates of the number of marine
mammals that might be ``taken'', NMFS must consider other factors, such
as the likely nature of any responses (their intensity, duration,
etc.), the context of any responses (critical reproductive time or
location, migration, etc.), as well as the number and nature (e.g.,
severity) of estimated Level A harassment takes, the number of
estimated mortalities, and the status of the species.
The Navy's specified activities have been described based on best
estimates of the maximum amount of sonar and other acoustic source use
or detonations that the Navy would conduct. There may be some
flexibility in that the exact number of hours, items, or detonations
may vary from year to year, but take totals are not authorized to
exceed the 5-year totals indicated in Table 11. We base our analysis
and NID on the maximum number of takes authorized.
To avoid repetition, we provide some general analysis immediately
below that applies to all the species listed in Table 11, given that
some of the anticipated effects (or lack thereof) 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, or groups of species where relevant similarities
exist, to provide more specific information related to the anticipated
effects on individuals 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 population.
The Navy's take request is based on its model and post-model
analysis. In the discussions below, the ``acoustic analysis'' refers to
the Navy's modeling results and post-model analysis. The model
calculates sound energy propagation from sonars, 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 received by a marine mammal exceeds the thresholds for effects.
The model estimates are then further analyzed to consider animal

[[Page 46152]]

avoidance and implementation of highly effective mitigation measures to
prevent Level A harassment, resulting in final estimates of effects due
to Navy training and testing. NMFS provided input to the Navy on this
process and the Navy's qualitative analysis is described in detail in
Chapter 6 of their LOA application (https://www.nmfs.noaa.gov/pr/permits/incidental/).
Generally speaking, and especially with other factors being equal,
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 throughout species, individuals, or
circumstances) and less severe effects from takes resulting from
exposure to lower received levels. It is important to note that the
requested and authorized number of 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 B or
Level A harassment threshold) that would occur. Additionally, these
instances may represent either a very brief exposure (seconds) or, in
some cases, longer durations of exposure within a day. Depending on the
location, duration, and frequency of activities, along with the
distribution and movement of marine mammals, individual animals may be
exposed to impulse or non-impulse sounds at or above the harassment
thresholds on multiple days. However, the Navy is currently unable to
estimate the number of individuals that may be taken during training
and testing activities. The model results estimate the total number of
takes that may occur to a smaller number of individuals. While the
model shows that an increased number of exposures may take place due to
an increase in events/activities and ordnance, the types and severity
of individual responses to training and testing activities are not
expected to change.

Behavioral Harassment

As discussed previously in the proposed rule, marine mammals can
respond to MFAS/HFAS in many different ways, a subset of which
qualifies as harassment (see Behavioral Harassment section of proposed
rule). One thing that the Level B harassment take estimates do not take
into account is the fact that most marine mammals will likely avoid
strong sound sources to one extent or another. Although an animal that
avoids the sound source will likely still be taken in some instances
(such as if the avoidance results in a missed opportunity to feed,
interruption of reproductive behaviors, etc.), in other cases avoidance
may result in fewer instances of take than were estimated or in the
takes resulting from exposure to a lower received level than was
estimated, which could result in a less severe response. For MFAS/HFAS,
the Navy provided information (Table 12) estimating the percentage of
behavioral harassment that would occur within the 6-dB bins (without
considering mitigation or avoidance). As mentioned above, an animal's
exposure to a higher received level is more likely to result in a
behavioral response that is more likely to adversely affect the health
of the animal. As illustrated below, the majority (about 80 percent, at
least for hull-mounted sonar, which is responsible for most of the
sonar takes) of calculated takes from MFAS result from exposures
between 150 dB and 162 dB. Less than one percent of the takes are
expected to result from exposures above 174 dB.
Specifically, given a range of behavioral responses that may be
classified as Level B harassment, to the degree that higher received
levels are expected to result in more severe behavioral responses, only
a small percentage of the anticipated Level B harassment from Navy
activities might necessarily be expected to potentially result in more
severe responses, especially when the distance from the source at which
the levels below are received is considered (see Table 12). Marine
mammals are able to discern the distance of a given sound source, and
given other equal factors (including received level), they have been
reported to respond more to sounds that are closer (DeRuiter et al.,
2013). Further, the estimated number of responses do not reflect either
the duration or context of those anticipated responses, some of which
will be of very short duration, and other factors should be considered
when predicting how the estimated takes may affect individual fitness.

Table 12--Non-Impulsive Ranges in 6-db Bins and Percentage of Behavioral Harassments
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sonar bin MF1 (e.g., SQS-53; Sonar bin MF4 (e.g., AQS-22; Sonar bin MF5 (e.g., SSQ-62; Sonar bin HF4 (e.g., SQQ-32;
ASW hull mounted sonar) ASW dipping sonar) ASW sonobuoy) MIW sonar)
-------------------------------------------------------------------------------------------------------------------------------
Percentage Percentage Percentage Percentage
of of of of
Received level Distance at which behavioral Distance at which behavioral Distance at which behavioral Distance at which behavioral
levels occur harassments levels occur harassments levels occur harassments levels occur harassments
within radius of occurring within radius of occurring within radius of occurring within radius of occurring
source (m) at given source (m) at given source (m) at given source (m) at given
levels levels levels levels
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Low Frequency Cetaceans
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
120 <=SPL <126.................................................. 183,000-133,000 <1 71,000-65,000 <1 18,000-13,000 <1 2,300-1,700 <1
126 <=SPL <132.................................................. 133,000-126,000 <1 65,000-60,000 <1 13,000-7,600 <1 1,700-1,200 <1
132 <=SPL <138.................................................. 126,000-73,000 <3 60,000-8,200 42 7,600-2,800 12 1,200-750 <1
138 <=SPL <144.................................................. 73,000-67,000 <1 8,200-3,500 10 2,800-900 26 750-500 5
144 <=SPL <150.................................................. 67,000-61,000 3 3,500-1,800 12 900-500 15 500-300 17
150 <=SPL <156.................................................. 61,000-17,000 68 1,800-950 15 500-250 21 300-150 34
156 <=SPL <162.................................................. 17,000-10,300 12 950-450 13 250-100 20 150-100 20
162 <=SPL <168.................................................. 10,200 5,600 9 450-200 6 100-<50 6 100-<50 24
168 <=SPL <174.................................................. 5,600-1,600 6 200-100 2 <50 <1 <50 <1
174 <=SPL <180.................................................. 1,600-800 <1 100-<50 <1 <50 <1 <50 <1
180 <=SPL <186.................................................. 800-400 <1 <50 <1 <50 <1 <50 <1
186 <=SPL <192.................................................. 400-200 <1 <50 <1 <50 <1 <50 <1
192 <= SPL <198................................................. 200-100 <1 <50 <1 <50 <1 <50 <1
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Mid-Frequency Cetaceans
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
120 <= SPL <126................................................. 184,000-133,000 <1 72,000-66,000 <1 19,000-15,000 <1 3,600-2,800 <1
126 <= SPL <132................................................. 133,000-126,000 <1 66,000-60,000 <1 15,000-8,500 <1 2,800-2,100 <1
132 <= SPL <138................................................. 126,000-73,000 <1 60,000-8,300 41 8,500-3,300 3 2,100-1,500 <1
138 <= SPL <144................................................. 73,000-67,000 <1 8,300-3,600 10 3,300-1,000 12 1,500-1,000 3
144 <= SPL <150................................................. 67,000-61,000 3 3,600-1,900 12 1,000-500 10 1,00-700 10

[[Page 46153]]

150 <= SPL <156................................................. 61,000-18,000 68 1,900-950 15 500-300 22 700-450 21
156 <= SPL <162................................................. 18,000-10,300 13 950-480 12 300-150 27 450-250 32
162 <= SPL <168................................................. 10,300-5,700 9 480-200 7 150-<50 25 250-150 19
168 <= SPL <174................................................. 5,700-1,700 6 200-100 2 <50 <1 150-100 9
174 <= SPL <180................................................. 1,700-900 <1 100-<50 <1 <50 <1 100-<50 6
180 <= SPL <186................................................. 900-400 <1 <50 <1 <50 <1 <50 <1
186 <= SPL <192................................................. 400-200 <1 <50 <1 <50 <1 <50 <1
192 <= SPL <198................................................. 200-100 <1 <50 <1 <50 <1 <50 <1
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Although the Navy has been monitoring the effects of MFAS/HFAS on
marine mammals since 2006, and research on the effects of MFAS is
advancing, our understanding of exactly how marine mammals in the Study
Area will respond to MFAS/HFAS is still growing. The Navy has submitted
reports from more than 60 major exercises across Navy range complexes
that indicate no behavioral disturbance was observed. One cannot
conclude from these results that marine mammals were not harassed from
MFAS/HFAS, as a portion of animals within the area of concern were not
seen (especially those more cryptic, deep-diving species, such as
beaked whales or Kogia spp.), the full series of behaviors that would
more accurately show an important change is not typically seen (i.e.,
only the surface behaviors are observed), and some of the non-biologist
watchstanders might not be well-qualified to characterize behaviors.
However, one can say that the animals that were observed did not
respond in any of the obviously more severe ways, such as panic,
aggression, or anti-predator response.

Diel Cycle

As noted previously, 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). 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 at-sea exercises
last 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
typically include assets that travel at high speeds (typically 10-15
knots, or higher) and likely cover large areas that are relatively far
from shore, in addition to the fact that marine mammals are 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. Additionally, 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 not to be likely for the majority of takes, does not mean
that a behavioral response is necessarily sustained for multiple days,
and still necessitates the consideration of likely duration and context
to assess any effects on the individual's fitness.
Durations for non-impulsive activities utilizing tactical sonar
sources vary and are fully described in Appendix A of the FEIS/OEIS.
ASW training and testing exercises using MFAS/HFAS generally last for
2-16 hours, and may have intervals of non-activity in between. Because
of the need to train in a large variety of situations, the Navy does
not typically conduct successive MTEs or other ASW exercises in the
same locations. Given the average length of ASW exercises (times of
continuous sonar use) and typical vessel speed, combined with the fact
that the majority of the cetaceans in the Study Area would not likely
remain in an area for successive days, it is unlikely that an animal
would be exposed to MFAS/HFAS at levels 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 exercises are of a short duration (1-6
hours). 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.

TTS

As mentioned previously, 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. 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 more powerful MF sources used have center frequencies
between 3.5 and 8 kHz and the other unidentified MF sources are, by
definition, less than 10 kHz, which suggests that TTS induced by any of
these MF sources would be in a frequency band somewhere between
approximately 2 and 20 kHz. 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 20 and 100 kHz,
which means that TTS could range up to 200 kHz; however, HF

[[Page 46154]]

systems are typically used less frequently and for shorter time periods
than surface ship and aircraft MF systems, so TTS from these sources is
even less likely). TTS from explosives would be broadband. Vocalization
data for each species, which would inform how TTS might specifically
interfere with communications with conspecifics, was provided in the
LOA application.
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 document. 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 knots). In the TTS studies, 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, MFAS emits a
nominal ping every 50 seconds, and incurring those levels of TTS is
highly unlikely.
3. Duration of TTS (recovery time)--In the TTS laboratory studies,
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 MFAS/HFAS training exercises in the 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 days (and any
incident of TTS would likely be far less severe due to the short
duration of the majority of the exercises and the speed of a typical
vessel). Also, for the same reasons discussed in the 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 (the source from which TTS would most
likely be sustained because the higher source level and slower
attenuation make it more likely that an animal would be exposed to a
higher received level) would not usually span the entire frequency
range of one vocalization type, much less span all types of
vocalizations or other critical auditory cues. If impaired, marine
mammals would typically be aware of their impairment and are sometimes
able to implement behaviors to compensate (see Acoustic Masking or
Communication Impairment section), though these compensations may incur
energetic costs.

Acoustic Masking or Communication Impairment

Masking only occurs during the time of the signal (and potential
secondary arrivals of indirect rays), versus TTS, which continues
beyond the duration of the signal. Standard MFAS nominally pings every
50 seconds for hull-mounted sources. For the sources for which we know
the pulse length, most are significantly shorter than hull-mounted
active sonar, on the order of several microseconds to tens of
microseconds. For hull-mounted active sonar, though some of the
vocalizations that marine mammals make are less than one second long,
there is only a 1 in 50 chance that they would occur exactly when the
ping was received, and when vocalizations are longer than one second,
only parts of them are masked. Alternately, when the pulses are only
several microseconds long, the majority of most animals' vocalizations
would not be masked. Masking effects from MFAS/HFAS are expected to be
minimal. If masking or communication impairment were to occur briefly,
it would be in the frequency range of MFAS, which overlaps with some
marine mammal 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 mimic the
characteristics of any marine mammal's vocalizations.

PTS, Injury, or Mortality

NMFS believes 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 vessel at a close distance, NMFS believes
that the mitigation measures (i.e., shutdown/powerdown zones for MFAS/
HFAS) 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
all ASW exercises) in addition to watchstanders on vessels to detect
marine mammals for mitigation implementation.
If a marine mammal is able to approach a surface vessel within the
distance necessary to incur PTS, the likely speed of the vessel
(nominal 10-15 knots) 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 mentioned previously and in relation
to TTS, the likely consequences to the health of an individual that
incurs PTS can range from mild to more serious, depending upon the
degree of PTS and the frequency band it is in, and many animals are
able to compensate for the shift, although it may include energetic
costs.
As discussed previously, marine mammals (especially beaked whales)
could potentially respond to MFAS at a received level lower than the
injury threshold in a manner that indirectly results in the animals
stranding. The exact mechanism of this potential response, behavioral
or physiological, is not known. When naval exercises have been
associated with strandings in the past, it has typically been when
three or more vessels are operating simultaneously, in the presence of
a strong surface duct, and in areas of constricted channels, semi-
enclosed areas, and/or steep bathymetry. A combination of these
environmental and operational parameters is not present in the MITT
action. When this is combined with consideration of the number of hours
of active sonar training that will be conducted and the nature of the
exercises--which do not typically include the use of multiple hull-
mounted sonar sources--we believe that the probability is small that
this will occur. Furthermore, given that there has never been a
stranding in the Study Area associated with sonar use and based on the
number of occurrences where strandings have been definitively
associated with military sonar versus the number of hours of active
sonar training that have been conducted, we believe that the
probability is small that this will occur as a result of the Navy's
proposed training and testing activities.

[[Page 46155]]

Lastly, an active sonar shutdown protocol for strandings involving live
animals milling in the water minimizes the chances that these types of
events turn into mortalities.
As stated previously, there have been no recorded Navy vessel
strikes of any marine mammals during training or testing in the MITT
Study Area to date, nor were takes by injury or mortality resulting
from vessel strike predicted in the Navy's analysis.

Important Marine Mammal Habitat

No critical habitat for marine mammals species protected under the
ESA has been designated in the MITT Study Area. There are also no known
specific breeding or calving areas for marine mammals within the MITT
Study Area.

Group and Species-Specific Analysis

Predicted harassment of marine mammals from exposures to sonar and
other active acoustic sources and explosions during annual training and
testing activities are shown in Table 11. The vast majority of
predicted exposures are expected to be Level B harassment (non-
injurious TTS and behavioral reactions) from sonar and other active
acoustic sources at relatively low received levels (less than 156 dB)
(Table 22). As mentioned earlier in the Analysis and Negligible Impact
Determination section, an animal's exposure to a higher received level
is more likely to adversely affect the health of the animal. The
acoustic analysis predicts the majority of marine mammal species in the
Study Area would not be exposed to explosive (impulse) sources
associated with training and testing activities that exceed the
impulsive sound thresholds for injury (Table 9). Only dwarf sperm
whale, pygmy sperm whale, Fraser's dolphin, and pantropical spotted
dolphin are predicted to have Level B (TTS) exposures resulting from
explosives, and only small numbers of dwarf sperm whales and pygmy
sperm whales are expected to have injurious take (PTS or minor tissue
damage from explosives) resulting from sonar and other active acoustic
sources and explosions. There are no lethal takes predicted for any
marine mammal species for the MITT activities.
The analysis below may in some cases (e.g., mysticetes, dolphins)
address species collectively if they occupy the same functional hearing
group (i.e., low, mid, and high-frequency cetaceans and pinnipeds in
water), have similar hearing capabilities, and/or are known to
generally behaviorally respond similarly to acoustic stressors. Where
there are meaningful differences between species or stocks, or groups
of species, in anticipated individual responses to activities, impact
of expected take on the population due to differences in population
status, or impacts on habitat, they will either be described within the
section or the species will be included as a separate sub-section. See
the Brief Background on Sound section in the proposed rule for a
description of marine mammal functional hearing groups as originally
designated by Southall et al. (2007).
Mysticetes--The Navy's acoustic analysis predicts 1,837 takes
(Level B harassment) may occur from sonar and other active acoustic
stressors associated with mostly training and some testing activities
in the Study Area each year. The acoustic analysis indicates up to 28
annual instances of Level B harassment (24 TTS and 4 behavioral
reactions) of fin whales, up to 28 annual instances of Level B
harassment (25 TTS and 3 behavioral reactions) of blue whales, up to
319 annual instances of Level B harassment (258 TTS and 61 behavioral
reactions) of sei whales, up to 860 annual instances of Level B
harassment (679 TTS and 181 behavioral reactions) of humpback whales,
up to 398 annual instances of Level B harassment (219 TTS and 79
behavioral reactions) of Bryde's whales, up to 101 annual instances of
Level B harassment (81 TTS and 20 behavioral reactions of minke whales,
and up to 103 annual instances of Level B harassment (84 TTS and 19
behavioral reactions) of Omura's whales.
Of these species, humpback, blue, fin, and sei whales are listed as
endangered under the ESA and depleted under the MMPA. NMFS has
designated two Pacific stocks for blue whales (Eastern North Pacific
and Central North Pacific) (Carretta et al., 2014), with blue whales in
the Study Area most likely part of the Central North Pacific stock.
NMFS has designated four Pacific stocks for humpback whales (Western
North Pacific, Central North Pacific, California/Oregon/Washington, and
American Samoa) (Carretta et al., 2014; Allen and Angliss, 2014), and
while stock structure is not completely known for the Study Area, it is
most likely that humpback whales here are part of the Western North
Pacific and/or Central North Pacific stock. Although NMFS has
designated Pacific stocks for fin, sei, Bryde's, minke, and Omura's
whales (Carretta et al., 2014; Allen and Angliss, 2014), little is
known about the stock structure for these species in the MITT Study
Area and NMFS currently has not designated any stocks specific to the
MITT Study Area for these species.
The estimates given above represent the total number of exposures
and not necessarily the number of individuals exposed, as a single
individual may be exposed multiple times over the course of a year. In
the ocean, the use of sonar and other active acoustic sources is
transient and is unlikely to repeatedly expose the same population of
animals over a short period. Around heavily trafficked Navy ports and
on fixed ranges, the possibility is greater for animals that are
resident during all or part of the year to be exposed multiple times to
sonar and other active acoustic sources. However, as discussed in the
proposed rule, because neither the vessels nor the animals are
stationary, significant long-term effects from repeated exposure are
not expected.
Level B harassment is anticipated to be in the form of non-TTS
behavioral responses and TTS, and no injurious (Level A harassment)
takes of mysticete whales from sonar and other active acoustic
stressors or explosives are expected. The majority of acoustic effects
to mysticetes from sonar and other active sound sources during training
and testing activitites would be primarily from anti-submarine warfare
events involving surface ships and hull mounted (mid-frequency) sonar.
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
grounds (i.e., breeding or feeding). Reactions may include alerting,
breaking off feeding dives and surfacing, diving or swimming away, or
no response at all (Richardson, 1995; Nowacek, 2007; Southall et al.,
2007). 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. It 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. Additionally, migrating animals
may ignore a sound source, or divert around the source if it is in
their path.
Specific to U.S. Navy systems using low frequency sound, studies
were undertaken in 1997-98 pursuant to the Navy's Low Frequency Sound
Scientific Research Program. These studies found only short-term
responses to low frequency sound by mysticetes (fin, blue, and humpback
whales) including

[[Page 46156]]

changes in vocal activity and avoidance of the source vessel (Clark,
2001; Miller et al., 2000; Croll et al., 2001; Fristrup et al., 2003;
Nowacek et al., 2007). Baleen whales exposed to moderate low-frequency
signals demonstrated no variation in foraging activity (Croll et al.,
2001). Low-frequency signals of the Acoustic Thermometry of Ocean
Climate sound source were not found to affect dive times of humpback
whales in Hawaiian waters (Frankel and Clark, 2000).
Specific to mid-frequency sound, studies by Melc[oacute]n et al.
(2012) in the Southern California Bight found that the likelihood of
blue whale low-frequency calling (usually associated with feeding
behavior) decreased with an increased level of mid-frequency sonar,
beginning at a SPL of approximately 110-120 dB re 1 [mu]Pa. However, 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.
Preliminary results from the 2010-2011 field season of an ongoing
behavioral response study 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 mild and there was
a quick return to their baseline activity (Southall et al., 2012b).
Blue whales responded to a mid-frequency sound source, with a source
level between 160 and 210 dB re 1 [mu]Pa at 1 m and a received sound
level up to 160 dB re 1 [mu]Pa, by exhibiting generalized avoidance
responses and changes to dive behavior during controlled exposure
experiments (CEE) (Goldbogen et al., 2013). However, reactions were not
consistent across individuals based on received sound levels alone, and
likely were the result of a complex interaction between sound exposure
factors such as proximity to sound source and sound type (mid-frequency
sonar simulation vs. pseudo-random noise), environmental conditions,
and behavioral state. Surface feeding whales did not show a change in
behavior during CEEs, but deep feeding and non-feeding whales showed
temporary reactions that quickly abated after sound exposure. Distances
of the sound source from the whales during CEEs were sometimes less
than a mile. Furthermore, the more dramatic reactions reported by
Goldbogen et al. (2013) were from non-sonar like signals, a
pseudorandom noise that could likely have been a novel signal to blue
whales. The preliminary findings from Goldbogen et al. (2013) and
Melc[oacute]n et al. (2012) are generally consistent with the Navy's
criteria and thresholds for predicting behavioral effects to mysticetes
from sonar and other active acoustic sources used in the quantitative
acoustic effects analysis for MITT. The behavioral response function
predicts a probability of a substantive behavioral reaction for
individuals exposed to a received SPL of 120 dB re 1 [mu]Pa or greater,
with an increasing probability of reaction with increased received
level as demonstrated in Melc[oacute]n et al. (2012).
High-frequency systems are not within mysticetes' ideal hearing
range and it is unlikely that they would cause a significant behavioral
reaction.
Most Level B harassments to mysticetes from sonar would result from
received levels less than 156 dB SPL. Therefore, the majority of Level
B 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 short duration. As mentioned earlier in the Analysis and
Negligible Impact Determination section, we anticipate more severe
effects from takes when animals are exposed to higher received levels.
Most low-frequency (mysticetes) cetaceans observed in studies usually
avoided sound sources at levels of less than or equal to 160 dB re
1[mu]Pa. Occasional behavioral reactions are unlikely to cause long-
term consequences for individual animals or populations. Even if sound
exposure were to be concentrated in a relatively small geographic area
over a long period of time (e.g., days or weeks during major training
exercises), we would expect that some individual whales would avoid
areas where exposures to acoustic stressors are at higher levels. For
example, Goldbogen et al. (2013) indicated some horizontal displacement
of deep foraging blue whales in response to simulated MFA sonar. Given
these animal's mobility and large ranges, we would expect these
individuals to temporarily select alternative foraging sites nearby
until the exposure levels in their initially selected foraging area
have decreased. Therefore, even temporary displacement from initially
selected foraging habitat is not expected to impact the fitness of any
individual animals because we would expect equivalent foraging to be
available in close proximity. Because we do not expect any fitness
consequences from any individual animals, we do not expect any
population level effects from these behavioral responses.
As explained above, recovery from a threshold shift (TTS) can take
a few minutes to a few days, depending on the exposure duration, sound
exposure level, and the magnitude of the initial shift, with larger
threshold shifts and longer exposure durations requiring longer
recovery times (Finneran et al., 2005; Finneran and Schlundt, 2010;
Mooney et al., 2009a; Mooney et al., 2009b). However, large threshold
shifts are not anticipated for these activities because of the
unlikelihood that animals will remain within the ensonified area (due
to the short duration of the majority of exercises, the speed of the
vessels, and the short distance within which the animal would need to
approach the sound source) at high levels for the duration necessary to
induce larger threshold shifts. Threshold shifts do not necessarily
affect all hearing frequencies equally, so some threshold shifts may
not interfere with an animal's hearing of biologically relevant sounds.
Furthermore, the implementation of mitigation and the sightability of
mysticetes (due to their large size) reduces the potential for a
significant behavioral reaction or a threshold shift to occur.
There has never been a vessel strike to a whale during any active
training or testing activities in the Study Area. A detailed analysis
of strike data is contained in Chapter 6 (Section 6.3.4, Estimated Take
of Large Whales by Navy Vessel Strike) of the LOA application. The Navy
does not anticipate vessel strikes to marine mammals during training or
testing activities within the Study Area, nor were takes by injury or
mortality resulting from vessel strike predicted in the Navy's
analysis. Therefore, NMFS is not authorizing mysticete takes (by injury
or mortality) from vessel strikes during the 5-year period of the MITT
regulations.
There is no designated critical habitat for mysticetes in the Study
Area. There are also no areas of specific importance for reproduction,
calving, or feeding for mysticetes in the Study Area.
Sperm Whales--The Navy's acoustic analysis indicates that 506
instances of Level B harassment of sperm whales may occur each year
from sonar or other active acoustic stressors during training and
testing activities. These Level B takes are anticipated to be in the
form of TTS (54) and behavioral reactions (452) and no injurious takes
of sperm whales from sonar and other active acoustic stressors or
explosives are requested or proposed for authorization. Although NMFS
has designated Pacific stocks for sperm whales (Carretta et al., 2014;
Allen and Angliss, 2014), little is known about the stock structure for
this species in the MITT Study Area and NMFS currently has not
designated any

[[Page 46157]]

sperm whale stocks specific to the MITT Study Area.
Sperm whales have shown resilience to acoustic and human
disturbance, although they may react to sound sources and activities
within a few kilometers. Sperm whales that are exposed to activities
that involve the use of sonar and other active acoustic sources may
alert, ignore the stimulus, avoid the area by swimming away or diving,
or display aggressive behavior (Richardson, 1995; Nowacek, 2007;
Southall et al., 2007). Some (but not all) sperm whale vocalizations
might overlap with the MFAS/HFAS TTS frequency range, which could
temporarily decrease an animal's sensitivity to the calls of
conspecifics or returning echolocation signals. However, as noted
previously, NMFS does not anticipate TTS of a long duration or severe
degree to occur as a result of exposure to MFAS/HFAS. Recovery from a
threshold shift (TTS) can take a few minutes to a few days, depending
on the exposure duration, sound exposure level, and the magnitude of
the initial shift, with larger threshold shifts and longer exposure
durations requiring longer recovery times (Finneran et al., 2005;
Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney et al.,
2009b). However, large threshold shifts are not anticipated for these
activities because of the unlikelihood that animals will remain within
the ensonified area (due to the short duration of the majority of
exercises and the speed of the vessels) at high levels for the duration
necessary to induce larger threshold shifts. Also, 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. Threshold shifts do not necessarily affect all hearing
frequencies equally, so some threshold shifts may not interfere with an
animal's hearing of biologically relevant sounds. No sperm whales are
predicted to be exposed to MFAS/HFAS sound levels associated with PTS
or injury.
The majority of Level B takes are expected to be in the form of
milder responses (low-level exposures) and of a generally short
duration. Overall, the number of predicted behavioral reactions are
unlikely to cause long-term consequences for individual animals or
populations. The MITT activities are not expected to occur in an area/
time of specific importance for reproductive, feeding, or other known
critical behaviors for sperm whales. Consequently, the activities are
not expected to adversely impact rates of recruitment or survival of
sperm whales. Sperm whales are listed as endangered under the ESA (and
depleted under the MMPA); however, there is no designated critical
habitat in the Study Area.
There has never been a vessel strike to a sperm whale during any
active training or testing activities in the Study Area. A detailed
analysis of strike data is contained in Chapter 6 (Section 6.3.4,
Estimated Take of Large Whales by Navy Vessel Strike) of the LOA
application. The Navy does not anticipate vessel strikes to marine
mammals during training or testing activities within the Study Area,
nor were takes by injury or mortality resulting from vessel strike
predicted in the Navy's analysis. Therefore, NMFS is not authorizing
sperm whale takes (by injury or mortality) from vessel strikes during
the 5-year period of the MITT regulations.
Pygmy and Dwarf Sperm Whale--The Navy's acoustic analysis predicts
Level B harassment (non-TTS behavioral responses and TTS) of 5,579
pygmy sperm whales and 14,217 dwarf sperm whales may occur annually
from sonar and other active acoustic stressors and explosives
associated with training and testing activities in the Study Area.
These estimates represents the total number of exposures and not
necessarily the number of individuals exposed, as a single individual
may be exposed multiple times over the course of a year. Of the Level B
takes, 5,467 pygmy sperm whale and 13,901 dwarf sperm whale takes are
predicted to be in the form of TTS from mainly MFAS/HFAS. The Navy's
acoustic analysis (factoring in the post-model correction for avoidance
and mitigation) also indicates that 15 injurious (Level A harassment)
takes of pygmy sperm whale and 41 injurious (Level A harassment) takes
of dwarf sperm whale may occur annually from active sonar.
Although NMFS has designated Pacific stocks for pygmy and dwarf
sperm whales (Carretta et al., 2014), little is known about the stock
structure for these species in the MITT Study Area and NMFS currently
has not designated any pygmy and dwarf sperm whale stocks specific to
the MITT Study Area.
Recovery from a threshold shift (TTS; partial hearing loss) can
take a few minutes to a few days, depending on the exposure duration,
sound exposure level, and the magnitude of the initial shift, with
larger threshold shifts and longer exposure durations requiring longer
recovery times (Finneran et al., 2005; Mooney et al., 2009a; Mooney et
al., 2009b; Finneran and Schlundt, 2010). An animal incurring PTS would
not fully recover. However, large degrees of threshold shifts (PTS or
TTS) are not anticipated for these activities because of the
unlikelihood that animals will remain within the ensonified area (due
to the short duration of the majority of exercises, the speed of the
vessels, and the short distance within which the animal would need to
approach the sound source) at high levels for the duration necessary to
induce larger threshold shifts. Threshold shifts do not necessarily
affect all hearing frequencies equally, so some threshold shifts may
not interfere with an animal hearing biologically relevant sounds. The
likely consequences to the health of an individual that incurs PTS can
range from mild to more serious, depending upon the degree of PTS and
the frequency band it is in, and many animals are able to compensate
for the shift, although it may include energetic costs. Furthermore,
likely avoidance of intense activity and sound coupled with mitigation
measures would further reduce the potential for more-severe PTS
exposures to occur. If a pygmy or dwarf sperm whale is able to approach
a surface vessel within the distance necessary to incur PTS, the likely
speed of the vessel (nominal 10-15 knots) 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. Some Kogia spp.
vocalizations might overlap with the MFAS/HFAS TTS frequency range (2-
20 kHz), but the limited information for Kogia spp. indicates that
their clicks are at a much higher frequency and that their maximum
hearing sensitivity is between 90 and 150 kHz.
Research and observations on Kogia spp. are limited. These species
tend to avoid human activity and presumably anthropogenic sounds. Pygmy
and dwarf sperm whales may startle and leave the immediate area of
activity, reducing potential impacts. Pygmy and dwarf sperm whales have
been 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). Based on their
tendency to avoid acoustic stressors (e.g., quick diving and other
vertical avoidance maneuvers) coupled with the short duration and
intermittent nature (e.g., sonar pings during ASW activities occur
about every 50 seconds) of the majority of training and testing
exercises and the speed of the Navy vessels

[[Page 46158]]

involved, it is unlikely that animals would receive multiple exposures
over a short period of time, allowing animals to recover lost resources
(e.g., food) or opportunities (e.g., mating).
It is worth noting that the amount of explosive and acoustic energy
entering the water may be overestimated, as many explosions actually
occur upon impact with above-water targets. However, sources such as
these were modeled as exploding at 1-meter depth.
The predicted effects to Kogia spp. are expected to be mostly
temporary and unlikely to cause long-term consequences for individual
animals or populations. The MITT activities are not expected to occur
in an area/time of specific importance for reproductive, feeding, or
other known critical behaviors. Pacific stocks of Kogia are not
depleted under the MMPA. Consequently, the activities are not expected
to adversely impact rates of recruitment or survival of pygmy and dwarf
sperm whales.
Beaked Whales--The Navy's acoustic analysis predicts Level B
harassment of four species of beaked whale annually: 22,541 Cuvier's
beaked whales; 4,426 Blainville's beaked whale; 1,924 Longman's beaked
whale; and 3,897 ginko-toothed beaked whales. These estimates represent
the total number of exposures and not necessarily the number of
individuals exposed, as a single individual may be exposed multiple
times over the course of a year. These takes are anticipated to be in
the form of mainly non-TTS behavioral harassment and some TTS, and no
injurious takes of beaked whales from sonar and active acoustic
stressors or explosives were predicted. Of the Level B takes, 308
Cuvier's beaked whale, 73 Blainville's beaked whale, 29 Longman's
beaked whale, and 62 ginko-toothed beaked whale takes are predicted to
be in the form of TTS from sonar and other active acoustic sources.
Although NMFS has designated Pacific stocks for Cuvier's, Blainville's,
and Longman's beaked whales (Carretta et al., 2014; Allen and Angliss,
2014), little is known about the stock structure for beaked whales in
the MITT Study Area and NMFS currently has not designated any beaked
whale stocks specific to the MITT Study Area.
Of note, the number of beaked whales behaviorally harassed by
exposure to MFAS/HFAS is generally higher than the other species
because of the low Level B harassment threshold, which essentially
makes the ensonified area of effects significantly larger than for the
other species. Beaked whales have unique criteria based on specific
data that show these animals to be especially sensitive to sound
(McCarthy et al., 2011; Tyack et al., 2011). Beaked whale non-impulsive
behavioral criteria are used unweighted (i.e., without weighting the
received level before comparing it to the threshold (see Finneran and
Jenkins, 2012)). The Navy has adopted an unweighted 140 dB re 1
[micro]Pa SPL threshold for significant behavioral effects for all
beaked whales. The fact that the threshold is a step function and not a
curve (and assuming uniform density) means that the vast majority of
the takes occur in the very lowest levels that exceed the threshold (it
is estimated that approximately 80 percent of the takes are from
exposures of 140 dB to 146 dB), which means that the anticipated
effects for the majority of exposures are not expected to be severe (As
mentioned above, an animal's exposure to a higher received level is
more likely to result in a behavioral response that is more likely to
adversely affect the health of an animal). Further, Moretti et al.
(2014) recently derived an empirical risk function for Blainville's
beaked whale that predicts there is a 0.5 probability of disturbance at
a received level of 150 dB (CI: 144-155), suggesting that in some cases
the current Navy step function over-estimate the effects of an activity
using sonar on beaked whales. Irrespective of the Moretti et al. (2014)
risk function, NMFS' analysis assumes that all of the beaked whale
Level B takes that are proposed for authorization will occur, and we
base our negligible impact determination, in part, on the fact that
these exposures would mainly occur at the very lowest end of the 140-dB
behavioral harassment threshold where behavioral effects are expected
to be much less severe and generally temporary in nature.
Behavioral responses of beaked whales can range from a mild
orienting response, or a shifting of attention, to flight and panic
(Richardson, 1995; Nowacek, 2007; Southall et al., 2007; Finneran and
Jenkins, 2012). Research has also shown that beaked whales are
sensitive to the presence of human activity (Tyack et al., 2011;
Pirotta et al., 2012). 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). Some beaked whale vocalizations may overlap with the MFAS/HFAS
TTS frequency range (2-20 kHz); however, as noted above, NMFS does not
anticipate TTS of a serious degree or extended duration to occur as a
result of exposure to MFA/HFAS. Recovery from a threshold shift (TTS)
can take a few minutes to a few days, depending on the exposure
duration, sound exposure level, and the magnitude of the initial shift,
with larger threshold shifts and longer exposure durations requiring
longer recovery times (Finneran et al., 2005; Finneran and Schlundt,
2010; Mooney et al., 2009a; Mooney et al., 2009b). However, large
threshold shifts are not anticipated for these activities because of
the unlikelihood that animals will remain within the ensonified area
(due to the short duration of the majority of exercises, the speed of
the vessels, and the short distance within which the animal would need
to approach the sound source) at high levels for the duration necessary
to induce larger threshold shifts. Threshold shifts do not necessarily
affect all hearing frequencies equally, so some threshold shifts may
not interfere with an animal's hearing of biologically relevant sounds.
No beaked whales are predicted in the acoustic analysis to be
exposed to sound levels associated with PTS, other injury, or
mortality. After decades of the Navy conducting similar activities in
the MITT Study Area without incident, NMFS does not expect stranding,
injury, or mortality of beaked whales to occur as a result of Navy
activities. Therefore, NMFS is not authorizing any Level A (injury or
mortality) takes for beaked whales. Additionally, through the MMPA
process (which allows for adaptive management), NMFS and the Navy will
determine the appropriate way to proceed in the event that a causal
relationship were to be found between Navy activities and a future
stranding.
NMFS also considered New et al. (2013) and their mathematical model
simulating a functional link between foraging energetics and
requirements for survival and reproduction for 21 species of beaked
whales. However, NMFS concluded that the New et al. (2013) model lacks
critical data and accurate inputs necessary to form valid conclusions
specifically about impacts of anthropogenic sound from Navy activities
on specific beaked whale populations. The study itself notes the need
for ``future research,'' identifies ``key data needs'' relating to
input parameters that ``particularly affected'' the model results, and
states only that the use of the model ``in combination with more
detailed research'' could help predict the effects of management
actions on beaked whale species. In short, information is not currently
available to specifically support the use

[[Page 46159]]

of this model in a project-specific evaluation of the effects of Navy
activities on the impacted beaked whale species in MITT.
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 mid-frequency sonar use. 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 mid-frequency sonar. 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. 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; Moretti et al., 2009, 2010; Tyack et
al., 2010, 2011; McCarthy et al., 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., 2013).
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.
Populations of beaked whales and other odontocetes in the Bahamas
and other Navy fixed ranges that have been operating for tens of years
appear to be stable. Significant behavioral reactions 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 (Tyack et al., 2011; De Ruiter et al., 2013; Manzano-
Roth et al., 2013; Moretti et al., 2014). 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
more frequently than the MITT Study Area, 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. Finally, results from
passive acoustic monitoring estimated regional Cuvier's beaked whale
densities were higher than indicated by the NMFS's broad scale visual
surveys for the U.S. west coast (Hildebrand and McDonald, 2009). Based
on the findings above, it is clear that the Navy's long-term ongoing
use of sonar and other active acoustic sources has not precluded beaked
whales from also continuing to inhabit those areas.
In summary, based on the best available science, the Navy and NMFS
believe that beaked whales that exhibit a significant TTS or behavioral
reaction due to sonar and other active acoustic testing activities
would generally not have long-term consequences for individuals or
populations. Claridge (2013) speculates that sonar use in a Bahamas
range could have ``a possible population-level effect'' on beaked
whales based on lower abundance in comparison to control sites.
However, the study suffers from several shortcomings and incorrectly
assumes that the Navy range and control sites were identical. The
author also acknowledged that ``information currently available cannot
provide a quantitative answer to whether frequent sonar use at [the
Bahamas range] is causing stress to resident beaked whales,'' and
cautioned that the outcome of ongoing studies ``is a critical component
to understanding if there are population-level effects.'' Moore and
Barlow (2013) have noted a decline in beaked whale populations in a
broad area of the Pacific Ocean area out to 300 nm from the coast and
extending from the Canadian-U.S. border to the tip of Baja Mexico.
There are scientific caveats and limitations to the data used for that
analysis, as well as oceanographic and species assemblage changes on
the U.S. Pacific coast not thoroughly addressed. Interestingly,
however, in the small portion of that area overlapping the Navy's SOCAL
Range Complex, long-term residency by individual Cuvier's beaked whales
and higher densities provide indications that the proposed decline
noted elsewhere is not apparent where the Navy has been intensively
training and testing with sonar and other systems for decades.
There is no direct evidence that routine Navy training and testing
spanning decades has negatively impacted marine mammal populations at
any Navy range complex. In at least three decades of similar
activities, only one instance of injury to marine mammals (March 4,
2011; three long-beaked common dolphin at Silver Strand Training
Complex) has been documented as a result of training or testing using
an impulse source (underwater explosion) and the Navy implemented more
stringent mitigation measures as a result of this incident. Stranding
events coincident with Navy MFAS use in which exposure to sonar is
believed to have been a contributing factor were detailed in the
Stranding and Mortality section of the proposed rule (FR 79 15437).
However, for some of these stranding events, a causal relationship
between sonar exposure and the stranding could not be clearly
established (Cox et al., 2006). In other instances, sonar was
considered only one of several factors that, in their

[[Page 46160]]

aggregate, may have contributed to the stranding event (Freitas, 2004;
Cox et al., 2006). On March 24, 2015, a Cuvier's beaked whale stranded,
and eventually died, near Bile Bay, Merizo Guam. The Navy confirmed
that non-MTE sonar exercises took place in the MIRC from March 23-27,
2015. A necropsy was performed by the Guam Department of Agriculture,
Division of Aquatics and Wildlife with assistance from NOAA. Results of
the necropsy have yet to be released and no causal relationship between
the stranding and Navy activities has been determined at this time.
Because of the association between tactical MFA 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 a suite of mitigation
measures intended to more broadly minimize impacts to marine mammals,
the Navy and NMFS have a detailed Stranding Response Plan that outlines
reporting, communication, and response protocols intended both to
minimize the impacts of, and enhance the analysis of, any potential
stranding in areas where the Navy operates.
The MITT training and testing activities are not expected to occur
in an area/time of specific importance for reproductive, feeding, or
other known critical behaviors for beaked whales. The degree of
predicted Level B harassment is expected to be mild, and no beaked
whales are predicted in the acoustic analysis to be exposed to sound
levels associated with PTS, other injury, or mortality. Consequently,
the activities are not expected to adversely impact rates of
recruitment or survival of beaked whales.
Social Pelagic Species (Small Whales)--The Navy's acoustic analysis
predicts that the following numbers of Level B behavioral harassments
of the associated species will occur annually: 84 killer whales; 555
false killer whales; 105 pygmy killer whales; 1,815 short-finned pilot
whales; and 2,085 melon-headed whales; including the following numbers
of TTS, respectively: 15, 101, 19, 334, and 448. These estimates
represent the total number of exposures and not necessarily the number
of individuals exposed, as a single individual may be exposed multiple
times over the course of a year. Behavioral responses of social pelagic
small whales can range from a mild orienting response, or a shifting of
attention, to flight and panic (Richardson, 1995; Nowacek, 2007;
Southall et al., 2007; Finneran and Jenkins, 2012). No injurious takes
from active acoustic stressors or explosives are requested or proposed
for authorization.
Although NMFS has designated Pacific stocks for killer whales,
false killer whales, pygmy killer whales, short-finned pilot whales,
and melon-headed whales (Carretta et al., 2014; Allen and Angliss,
2014), little is known about the stock structure for these species in
the MITT Study Area and NMFS currently has not designated any stocks
for these species specific to the MITT Study Area.
As mentioned previously, TTS from MFAS is anticipated to occur
primarily in the 2-20 kHz range. If any individuals of these species
were to experience TTS from MFAS/HFAS, the TTS would likely overlap
with some of the vocalizations of conspecifics, and not with others.
However, as noted previously, NMFS does not anticipate TTS of a long
duration or severe degree to occur as a result of exposure to MFA/HFAS.
Recovery from a threshold shift (TTS) can take a few minutes to a few
days, depending on the exposure duration, sound exposure level, and the
magnitude of the initial shift, with larger threshold shifts and longer
exposure durations requiring longer recovery times (Finneran et al.,
2005; Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney et al.,
2009b). However, large threshold shifts are not anticipated for these
activities because of the unlikelihood that animals will remain within
the ensonified area (due to the short duration of the majority of
exercises, the speed of the vessels, and the short distance within
which the animal would need to approach the sound source) at high
levels for the duration necessary to induce larger threshold shifts.
Threshold shifts do not necessarily affect all hearing frequencies
equally, so some threshold shifts may not interfere with an animal's
hearing of biologically relevant sounds.
Controlled exposure experiments in 2007 and 2008 in the Bahamas
recorded responses of false killer whales, short-finned pilot whales,
and melon-headed whales to simulated MFA sonar (De Ruiter et al.,
2013). The responses to exposures between species were variable. After
hearing each MFAS signal, false killer whales were found to ``increase
their whistle production rate and made more-MFAS-like whistles'' (De
Ruiter et al., 2013). In contrast, melon-headed whales had ``minor
transient silencing'' after each MFAS signal, while pilot whales had no
apparent response.
Pilot whales or false killer whales in the Bahamas showed an
avoidance response to controlled exposure playbacks (Southall et al.,
2009). Consistent with the findings of other previous research (see,
for example Southall et al., 2007), De Ruiter et al., (2013b) found the
responses were variable by species and with the context of the sound
exposure. The assumption is that odontocete species in general,
including those in the MITT Study Area, would have similar variable
responses.
Research and observations show that if killer whales 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.
Killer whales 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. Killer whales
that are exposed to activities that involve the use of sonar and other
active acoustic sources may alert, ignore the stimulus, change their
behaviors or vocalizations, avoid the sound source by swimming away or
diving, or be attracted to the sound source. Research has demonstrated
that killer whales may routinely move over long large distances
(Andrews and Matkin, 2014; Fearnbach et al., 2013). In a similar
documented long-distance movement, an Eastern North Pacific Offshore
stock killer whale tagged off San Clemente Island, California, moved
(over a period of 147 days) to waters off northern Mexico, then north
to Cook Inlet, Alaska, and finally (when the tag ceased transmitting)
to coastal waters off Southeast Alaska (Falcone and Schorr, 2014).
Given these findings, temporary displacement due to avoidance of
training and testing activities are therefore unlikely to have
biological significance to individual animals. Long-term consequences
to individual killer whales or populations are not likely due to
exposure to sonar or other active acoustic sources. Population-level
consequences are not expected.
The MITT activities are not expected to occur in an area/time of
specific importance for reproductive, feeding, or other known critical
behaviors for social pelagic species. Consequently, the activities are
not expected to adversely impact rates of recruitment or survival of
these species.
Dolphins--The Navy's acoustic analysis predicts the following
numbers of Level B harassment annually: 741 bottlenose dolphin; 12,811
pantropical spotted dolphin; 3,298 striped dolphin; 589 spinner
dolphin; 1,819 rough toothed dolphin; 2,572 Fraser's dolphin;

[[Page 46161]]

and 505 Risso's dolphin. These estimates represent the total number of
exposures and not necessarily the number of individuals exposed, as a
single individual may be exposed multiple times over the course of a
year. The majority of takes are anticipated to be by non-TTS behavioral
harassment in the form of milder responses (low received levels and of
a short duration) to sonar and other active acoustic sources. No
injurious takes of dolphins from active acoustic stressors or
explosives are requested or proposed for authorization. Behavioral
responses can range from alerting, to changing their behavior or
vocalizations, to avoiding the sound source by swimming away or diving
(Richardson, 1995; Nowacek, 2007; Southall et al., 2007).
Of the Level B takes, 150 bottlenose dolphin; 2,584 pantropical
spotted dolphin; 612 striped dolphin; 119 spinner dolphin; 377 rough
toothed dolphin; 493 Fraser's dolphin; and 84 Risso's dolphin takes are
predicted to be in the form of generally mild TTS from sonar and other
active acoustic sources. Though the group size and behavior of these
species makes it likely that Navy lookouts would detect them and
implement shutdown if appropriate, the proposed mitigation has a
provision that allows the Navy to continue operation of MFAS if the
animals are clearly bow-riding even after the Navy has initially
maneuvered to try and avoid closing with the animals. As mentioned
above, many of the recorded dolphin vocalizations overlap with the
MFAS/HFAS TTS frequency range (2-20 kHz), however, as noted above, NMFS
does not anticipate TTS of a serious degree or extended duration to
occur. Recovery from a threshold shift (TTS) can take a few minutes to
a few days, depending on the exposure duration, sound exposure level,
and the magnitude of the initial shift, with larger threshold shifts
and longer exposure durations requiring longer recovery times (Finneran
et al., 2005; Finneran and Schlundt, 2010; Mooney et al., 2009a; Mooney
et al., 2009b). However, large threshold shifts are not anticipated for
these activities because of the unlikelihood that animals will remain
within the ensonified area (due to the short duration of the majority
of exercises, the speed of the vessels, and the short distance within
which the animal would need to approach the sound source) at high
levels for the duration necessary to induce larger threshold shifts.
Threshold shifts do not necessarily affect all hearing frequencies
equally, so some threshold shifts may not interfere with an animal's
hearing of biologically relevant sounds.
One Level B take each for Fraser's dolphin and pantropical spotted
dolphin is predicted to be in the form of non-injurious TTS from
impulsive sound sources (explosive detonations). Research and
observations suggest that if delphinids are exposed to impulse sound
sources, they may react by alerting, ignoring the stimulus, changing
their behavior or vocalizations, or avoiding the area by swimming away
or diving (Richardson, 1995; Finneran, 2002; Madsen et al., 2006; Weir,
2008; and Miller et al., 2009).
Although NMFS has designated Pacific stocks for bottlenose,
pantropical spotted, striped, spinner, rough toothed, Fraser's, and
Risso's dolphins (Carretta et al., 2014), little is known about the
stock structure for these species in the MITT Study Area and NMFS
currently has not designated any stocks for these species specific to
the MITT Study Area.
The MITT activities are not expected to occur in an area/time of
specific importance for reproductive, feeding, or other known critical
behaviors for dolphins. Consequently, the activities are not expected
to adversely impact rates of recruitment or survival of these species.

Long-Term Consequences

The best assessment of long-term consequences from training and
testing activities will be to monitor the populations over time within
a given Navy range complex. A U.S. workshop on Marine Mammals and Sound
(Fitch et al., 2011) indicated a critical need for baseline biological
data on marine mammal abundance, distribution, habitat, and behavior
over sufficient time and space to evaluate impacts from human-generated
activities on long-term population survival. The Navy has developed
monitoring plans for protected marine mammals occurring on Navy ranges
with the goal of assessing the impacts of training and testing
activities on marine species and the effectiveness of the Navy's
current mitigation practices. Continued monitoring efforts over time
will be necessary to completely evaluate the long-term consequences of
exposure to noise sources.
Since 2006 across all Navy range complexes (in the Atlantic, Gulf
of Mexico, and the Pacific), there have been more than 80 reports;
Major Exercise Reports, Annual Exercise Reports, and Monitoring
Reports. For the Pacific since 2011, there have been 29 monitoring and
exercise reports submitted to NMFS to further research goals aimed at
understanding the Navy's impact on the environment as it carries out
its mission to train and test (www.navymarinespeciesmonitoring.us).
In addition to this multi-year record of reports from across the
Navy, there have also been ongoing Behavioral Response Study research
efforts (in Southern California and the Bahamas) specifically focused
on determining the potential effects from Navy mid-frequency sonar
(Southall et al., 2011, 2012; Tyack et al., 2011; DeRuiter et al.,
2013b; Goldbogen et al., 2013; Moretti et al., 2014). This multi-year
compendium of monitoring, observation, study, and broad scientific
research is informative with regard to assessing the effects of Navy
training and testing in general. Given that this record involves many
of the same Navy training and testing activities being considered for
the Study Area and because it includes all the marine mammal taxonomic
families and many of the same species, this compendium of Navy
reporting is directly applicable to assessing locations such as the
Mariana Islands.
In the Hawaii and Southern California Navy training and testing
ranges from 2009 to 2012, Navy-funded marine mammal monitoring research
completed over 5,000 hours of visual survey effort covering over 65,000
nautical miles, sighted over 256,000 individual marine mammals, took
over 45,600 digital photos and 36 hours of digital video, attached 70
satellite tracking tags to individual marine mammals, and collected
over 40,000 hours of passive acoustic recordings. In Hawaii alone
between 2006 and 2012, there were 21 scientific marine mammal surveys
conducted before, during, or after major exercises.
Based on monitoring conducted before, during, and after Navy
training and testing events since 2006, the NMFS' assessment is that it
is unlikely there will be impacts having any long-term consequences to
populations of marine mammals as a result of the proposed continuation
of training and testing in the ocean areas historically used by the
Navy including the MITT Study Area. This assessment of likelihood is
based on four indicators from areas in the Pacific where Navy training
and testing has been ongoing for decades: (1) Evidence suggesting or
documenting increases in the numbers of marine mammals present
(Calambokidis and Barlow, 2004; Falcone et al., 2009; Hildebrand and
McDonald, 2009; Falcone and Shorr, 2012; Calambokidis et al., 2009a;
Berman-Kowalewski et al., 2010; Moore and Barlow, 2011; Barlow et al.
2011; Kerosky et al,. 2012; Smultea et al., 2013), or evidence
suggesting

[[Page 46162]]

populations have reached carrying capacity (Monnahan et al., 2014), (2)
examples of documented presence and site fidelity of species and long-
term residence by individual animals of some species (Hooker et al.,
2002; McSweeney et al., 2007; McSweeney et al., 2009; McSweeney et al.,
2010; Martin and Kok, 2011; Baumann-Pickering et al., 2012; Falcone and
Schorr, 2014), (3) use of training and testing areas for breeding and
nursing activities (Littnan, 2010), and (4) eight years of
comprehensive monitoring data indicating a lack of any observable
effects to marine mammal populations as a result of Navy training and
testing activities.
To summarize, while the evidence covers most marine mammal
taxonomic suborders, it is limited to a few species and only suggestive
of the general viability of those species in intensively used Navy
training and testing areas (Barlow et al., 2011; Calambokidis et al.,
2009b; Falcone et al., 2009; Littnan, 2011; Martin and Kok, 2011;
McCarthy et al., 2011; McSweeney et al., 2007; McSweeney et al., 2009;
Moore and Barlow, 2011; Tyack et al., 2011; Southall et al., 2012a;
Melcon, 2012; Goldbogen, 2013; Baird et al., 2013). However, there is
no direct evidence that routine Navy training and testing spanning
decades has negatively impacted marine mammal populations at any Navy
range complex. Although there have been a few strandings associated
with use of sonar in other locations (see U.S. Department of the Navy,
2013b), Ketten (2012) has recently summarized, ``to date, there has
been no demonstrable evidence of acute, traumatic, disruptive, or
profound auditory damage in any marine mammal as the result of
anthropogenic noise exposures, including sonar.'' Therefore, based on
the best available science (McSweeney et al., 2007; Falcone et al.,
2009; McSweeney et al., 2009; Littnan, 2010; Barlow et al., 2011;
Martin and Kok, 2011; McCarthy et al., 2011; Moore and Barlow, 2011;
Tyack et al., 2011; Southall et al., 2012a; Manzano-Roth et al., 2013;
DeRuiter et al., 2013; Goldbogen et al., 2013; Moretti et al., 2014;
Smultea and Jefferson, 2014), including data developed in the series of
reports submitted to NMFS, we believe that long-term consequences for
individuals or populations are unlikely to result from Navy training
and testing activities in the Study Area.

Final Determination

NMFS concludes that training and testing activities proposed in the
MITT Study Area could result in Level B and Level A takes, as
summarized in Table 11. Based on best available science NMFS concludes
that exposures to marine mammal species due to MITT activities would
result in primarily short-term (temporary and short in duration) and
relatively infrequent effects to most individuals, and not of the type
or severity that would be expected to be additive for the portion of
the stocks and species likely to be exposed. Marine mammal takes from
Navy activities are not expected to impact annual rates of recruitment
or survival and will therefore not result in population-level impacts
for the following reasons:
Most acoustic harassments (greater than 99 percent) are
within the non-injurious TTS or behavioral effects zones (Level B
harassment consisting of generally temporary modifications in behavior)
and none of the estimated exposures result in mortality.
As mentioned earlier, an animal's exposure to a higher
received level is more likely to result in a behavioral response that
is more likely to adversely affect the health of the animal. For low
frequency cetaceans (mysticetes) in the Study Area, most Level B
exposures will occur at received levels less than 156 dB (Table 22).
The majority of estimated odontocete takes from MFAS/HFAS (at least for
hull-mounted sonar, which is responsible for most of the sonar-related
takes) also result from exposures to received levels less than 156 dB
(Table 22). Therefore, the majority of Level B takes are expected to be
in the form of milder responses (i.e., lower-level exposures that still
rise to the level of a take, but would likely be less severe in the
range of responses that qualify as a take) and are not expected to have
deleterious impacts on the fitness of any individuals.
Acoustic disturbances caused by Navy sonar and explosives
are short-term, intermittent, and (in the case of sonar) transitory,
even during major training exercises. Navy activities are generally
unit level. Unit level events occur over a small spatial scale (one to
a few 10s of square miles) and with few participants (usually one or
two). Single-unit unit level training would typically involve a few
hours of sonar use, with a typical nominal ping of every 50 seconds
(duty cycle). Even though an animal's exposure to active sonar may be
more than one time, the intermittent nature of the sonar signal, its
low duty cycle, and the fact that both the vessel and animal are moving
provide a very small chance that exposure to active sonar for
individual animals and stocks would be repeated over extended periods
of time. Consequently, we would not expect the Navy's activities to
create conditions of long-term, continuous underwater noise leading to
habitat abandonment or long-term hormonal or physiological stress
responses in marine mammals.
Years of monitoring of Navy activities (since 2006) have
documented hundreds of thousands of marine mammals on the range
complexes and there are only two instances of overt behavioral change
that have been observed.
Years of monitoring of Navy activities have documented no
instances of injury to marine mammals as a direct result of non-impulse
acoustic sources.
In at least three decades of similar activities, only one
instance of injury to marine mammals (March 2011; three long-beaked
common dolphin off Southern California) has been documented as a result
of training or testing using an impulse source (underwater explosion).
Range complexes where intensive training and testing have
been occurring for decades have populations of multiple species with
strong site fidelity (including highly sensitive resident beaked whales
at some locations) and increases in the number of some species.
Populations of beaked whales and other odontocetes in the Bahamas, and
other Navy fixed ranges that have been operating for tens of years,
appear to be stable.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, which includes
consideration of the materials provided in the Navy's LOA application
and MITT FEIS/OEIS, and dependent upon the implementation of the
mitigation and monitoring measures, NMFS finds that the total marine
mammal take from the Navy's training and testing activities in the MITT
Study Area will have a negligible impact on the affected marine mammal
species or stocks. NMFS has issued regulations for these activities
that prescribe the means of effecting the least practicable adverse
impact on marine mammal species or stocks and their habitat and set
forth requirements pertaining to the monitoring and reporting of that
taking.

Impact on Availability of Affected Species for Taking for Subsistence
Uses

NMFS has determined that the issuance of regulations and subsequent
LOA for Navy training and testing activities in the MITT Study Area
would not have an unmitigable adverse impact on the availability of
species or stocks for subsistence use, since there are no such uses in
the specified area.

[[Page 46163]]

Endangered Species Act (ESA)

There are five marine mammal species under NMFS' jurisdiction that
are listed as endangered or threatened under the ESA with confirmed or
possible occurrence in the Study Area: Blue whale, humpback whale, fin
whale, sei whale, and sperm whale. The Navy consulted with NMFS
pursuant to section 7 of the ESA, and NMFS also consulted internally on
the issuance of an LOA under section 101(a)(5)(A) of the MMPA for MITT
activities. NMFS issued a Biological Opinion concluding that the
issuance of the rule and subsequent LOA are likely to adversely affect,
but are not likely to jeopardize, the continued existence of the
threatened and endangered species (and species proposed for listing)
under NMFS' jurisdiction and are not likely to result in the
destruction or adverse modification of critical habitat in the MITT
Study Area. The Biological Opinion for this action is available on
NMFS' Web site (https://www.nmfs.noaa.gov/pr/permits/incidental/).

National Environmental Policy Act (NEPA)

NMFS participated as a cooperating agency on the MITT FEIS/OEIS,
which was published on May 22, 2015 and is available on the Navy's Web
site: https://www.mitt-eis.com. NMFS determined that the MITT FEIS/OEIS
is adequate and appropriate to meet our responsibilities under NEPA for
the issuance of regulations and LOA and adopted the Navy's MITT FEIS/
OEIS.

Classification

The Office of Management and Budget has determined that this 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
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 LOA 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 the action would not result
in a significant economic impact on a substantial number of small
entities.
The Assistant Administrator for Fisheries has determined that there
is good cause under the Administrative Procedure Act (5 U.S.C
553(d)(3)) to waive the 30-day delay in the effective date of the
measures contained in the final rule. The Navy is the only entity
subject to the regulations, and it has informed NMFS that it requests
that this final rule take effect by August 3, 2015, when the
regulations issued by NMFS to govern the unintentional taking of marine
mammals incidental to the Navy's activities in the MIRC study area from
2010 to 2015 expire. Any delay of enacting the final rule would result
in either: (1) A suspension of planned naval training, which would
disrupt vital training essential to national security; or (2) the
Navy's procedural non-compliance with the MMPA (should the Navy conduct
training without an LOA), thereby resulting in the potential for
unauthorized takes of marine mammals. Moreover, the Navy is ready to
implement the rule immediately. For these reasons, the Assistant
Administrator finds good cause to waive the 30-day delay in the
effective date.

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: July 24, 2015.
Paul N. Doremus,
Deputy Assistant Administrator for Operations, National Marine
Fisheries Service.

For reasons set forth in the preamble, 50 CFR part 218 is 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 follow:

Authority: 16 U.S.C. 1361 et seq.

0
2. Subpart J is added to part 218 to read as follows:
Subpart J--Taking and Importing Marine Mammals; U.S. Navy's Mariana
Islands Training and Testing (MITT)
Sec.
218.90 Specified activity and specified geographical region.
218.91 Effective dates and definitions.
218.92 Permissible methods of taking.
218.93 Prohibitions.
218.94 Mitigation.
218.95 Requirements for monitoring and reporting.
218.96 Applications for Letters of Authorization.
218.97 Letter of Authorization.
218.98 Renewal and modifications of Letters of Authorization.

Subpart J--Taking and Importing Marine Mammals; U.S. Navy's Mariana
Islands Training and Testing (MITT)

Sec. 218.90 Specified activity and specified geographical region.

(a) Regulations in this subpart apply only to the U.S. Navy for the
taking of marine mammals that occurs in the area outlined in paragraph
(b) of this section and that occurs incidental to the activities
described in paragraph (c) of this section.
(b) The taking of marine mammals by the Navy is only authorized if
it occurs within the MITT Study Area, which includes the Mariana
Islands Range Complex (MIRC) and areas to the north and west. The Study
Area includes established ranges, operating areas, warning areas, and
special use airspace in the region of the Mariana Islands that are part
of the MIRC, its surrounding seas, and a transit corridor to the Hawaii
Range Complex. The Study Area also includes Navy pierside locations
where sonar maintenance and testing may occur.
(c) The taking of marine mammals by the Navy is only authorized if
it occurs incidental to the following activities within the designated
amounts of use:
(1) Non-impulsive Sources Used During Training and Testing:
(i) Low-frequency (LF) Source Classes:
(A) LF4--an average of 123 hours per year.
(B) LF5--an average of 11 hours per year.
(C) LF6--an average of 40 hours per year.
(ii) Mid-frequency (MF) Source Classes:
(A) MF1--an average of 1,872 hours per year.
(B) MF2--an average of 625 hours per year.
(C) MF3--an average of 192 hours per year.

[[Page 46164]]

(D) MF4--an average of 214 hours per year.
(E) MF5--an average of 2,588 items per year.
(F) MF6--an average of 33 items per year.
(G) MF8--an average of 123 hours per year.
(H) MF9--an average of 47 hours per year.
(I) MF10--an average of 231 hours per year.
(J) MF11--an average of 324 hours per year.
(K) MF12--an average of 656 hours per year.
(iii) High-frequency (HF) and Very High-frequency (VHF) Source
Classes:
(A) HF1--an average of 113 hours per year.
(B) HF4--an average of 1,060 hours per year.
(C) HF5--an average of 336 hours per year.
(D) HF6--an average of 1,173 hours per year.
(iv) Anti-Submarine Warfare (ASW) Source Classes:
(A) ASW1--an average of 144 hours per year.
(B) ASW2--an average of 660 items per year.
(C) ASW3--an average of 3,935 hours per year.
(D) ASW4--an average of 32 items per year.
(v) Torpedoes (TORP) Source Classes:
(A) TORP1--an average of 115 items per year.
(B) TORP2--an average of 62 items per year.
(vi) Acoustic Modems (M):
(A) M3--an average of 112 hours per year.
(B) [Reserved]
(vii) Swimmer Detection Sonar (SD):
(A) SD1--an average 2,341 hours per year.
(B) [Reserved]
(2) Impulsive Source Detonations During Training and Testing:
(i) Explosive Classes:
(A) E1 (0.1 to 0.25 lb NEW)--an average of 10,140 detonations per
year.
(B) E2 (0.26 to 0.5 lb NEW)--an average of 106 detonations per
year.
(C) E3 (>0.5 to 2.5 lb NEW)--an average of 932 detonations per
year.
(D) E4 (>2.5 to 5 lb NEW)--an average of 420 detonations per year.
(E) E5 (>5 to 10 lb NEW)--an average of 684 detonations per year.
(F) E6 (>10 to 20 lb NEW)--an average of 76 detonations per year.
(G) E8 (>60 to 100 lb NEW)--an average of 16 detonations per year.
(H) E9 (>100 to 250 lb NEW)--an average of 4 detonations per year.
(I) E10 (>250 to 500 lb NEW)--an average of 12 detonations per
year.
(J) E11 (>500 to 650 lb NEW)--an average of 6 detonations per year.
(K) E12 (>650 to 2,000 lb NEW)--an average of 184 detonations per
year.
(ii) [Reserved]

Sec. 218.91 Effective dates and definitions.

(a) Regulations in this subpart are effective August 3, 2015
through August 3, 2020.
(b) The following definitions are utilized in these regulations:
(1) Uncommon Stranding Event (USE)--A stranding event that takes
place within an OPAREA where a Major Training Exercise (MTE) occurs and
involves any one of the following:
(i) Two or more individuals of any cetacean species (not including
mother/calf pairs, unless of species of concern listed in paragraph
(b)(1)(ii) of this section) found dead or live on shore within a 2-day
period and occurring within 30 miles of one another.
(ii) A single individual or mother/calf pair of any of the
following marine mammal species of concern: Beaked whale of any
species, Kogia spp., Risso's dolphin, melon-headed whale, pilot whale,
humpback whale, sperm whale, blue whale, fin whale, or sei whale.
(iii) A group of two or more cetaceans of any species exhibiting
indicators of distress.
(2) Shutdown--The cessation of active sonar operation or detonation
of explosives within 14 nautical miles of any live, in the water,
animal involved in a USE.

Sec. 218.92 Permissible methods of taking.

(a) Under a Letter of Authorization (LOA) issued pursuant to Sec.
218.97, the Holder of the Letter of Authorization may incidentally, but
not intentionally, take marine mammals within the area described in
Sec. 218.90, provided the activity is in compliance with all terms,
conditions, and requirements of these regulations and the appropriate
LOA.
(b) The activities identified in Sec. 218.90(c) must be conducted
in a manner that minimizes, to the greatest extent practicable, any
adverse impacts on marine mammals and their habitat.
(c) The incidental take of marine mammals under the activities
identified in Sec. 218.90(c) is limited to the following species, by
the identified method of take:
(1) Level B Harassment for all Training and Testing Activities:
(i) Mysticetes:
(A) Blue whale (Balaenoptera musculus)--140 (an average of 28
annually)
(B) Bryde's whale (Balaenoptera edeni)--1,990 (an average of 398
annually)
(C) Fin whale (Balaenoptera physalus)--140 (an average of 28
annually)
(D) Humpback whale (Megaptera novaeangliae)--4,300 (an average of
860 annually)
(E) Minke whale (Balaenoptera acutorostrata)--505 (an average of
101 annually)
(F) Sei whale (Balaenoptera borealis)--1,595 (an average of 319
annually)
(G) Omura's whale (Balaenoptera omurai)--515 (an average of 103
annually)
(ii) Odontocetes:
(A) Blainville's beaked whale (Mesoplodon densirostris)--22,130 (an
average of 4,426 annually)
(B) Bottlenose dolphin (Tursiops truncatus)--3,705 (an average of
741 annually)
(C) Cuvier's beaked whale (Ziphius cavirostris)--112,705 (an
average of 22,541 annually)
(D) Dwarf sperm whale (Kogia sima)--71,085 (an average of 14,217
annually)
(E) False killer whale (Pseudorca crassidens)--2,775 (an average of
555 annually)
(F) Fraser's dolphin (Lagenodelphis hosei)--12,860 (an average of
2,572 annually)
(G) Gingko-toothed beaked whale (Mesoplodon ginkgodens)--19,485 (an
average of 3,897 annually)
(H) Killer whale (Orcinus orca)--420 (an average of 84 annually)
(I) Longman's beaked whale (Indopacetus pacificus)--9,620 (an
average of 1,924 annually)
(J) Melon-headed whale (Peponocephala electra)--10,425 (an average
of 2,085 annually)
(K) Pantropical spotted dolphin (Stenella attenuata)--64,055 (an
average of 12,811 annually)
(L) Pygmy killer whale (Feresa attenuata)--525 (an average of 105
annually)
(M) Pygmy sperm whale (Kogia breviceps)--27,895 (an average of
5,579 annually)
(N) Risso's dolphin (Grampus griseus)--2,525 (an average of 505
annually)
(O) Rough-toothed dolphin (Steno bredanensis)--9,095 (an average of
1,819 annually)
(P) Short-finned pilot whale (Globicephala macrorhynchus)--9,075
(an average of 1,815 annually)
(Q) Sperm whale (Physeter macrocephalus)--2,530 (an average of 506
annually)
(R) Spinner dolphin (Stenella longirostris)--2,945 (an average of
589 annually)

[[Page 46165]]

(S) Striped dolphin (Stenella coerulealba)--16,490 (an average of
3,298 annually)
(2) Level A Harassment for all Training and Testing Activities:
(i) Odontocetes:
(A) Dwarf sperm whale (Kogia sima)--205 (an average of 41 annually)
(B) Pygmy sperm whale (Kogia breviceps)--75 (an average of 15
annually)
(ii) [Reserved]

Sec. 218.93 Prohibitions.

Notwithstanding takings contemplated in Sec. 218.92 and authorized
by an LOA issued under Sec. Sec. 216.106 and 218.97 of this chapter,
no person in connection with the activities described in Sec. 218.90
may:
(a) Take any marine mammal not specified in Sec. 218.92(c);
(b) Take any marine mammal specified in Sec. 218.92(c) other than
by incidental take as specified in Sec. 218.92(c);
(c) Take a marine mammal specified in Sec. 218.92(c) if such
taking results in more than a negligible impact on the species or
stocks of such marine mammal; or
(d) Violate, or fail to comply with, the terms, conditions, and
requirements of these regulations or an LOA issued under Sec. Sec.
216.106 and 218.97.

Sec. 218.94 Mitigation.

(a) When conducting training and testing activities, as identified
in Sec. 218.90, the mitigation measures contained in the LOA issued
under Sec. Sec. 216.106 and 218.97 of this chapter must be
implemented. These mitigation measures include, but are not limited to:
(1) Lookouts. The following are protective measures concerning the
use of lookouts.
(i) Lookouts positioned on surface ships will be dedicated solely
to diligent observation of the air and surface of the water. Their
observation objectives will include, but are not limited to, detecting
the presence of biological resources and recreational or fishing boats,
observing mitigation zones, and monitoring for vessel and personnel
safety concerns.
(ii) Lookouts positioned in aircraft or on boats will, to the
maximum extent practicable and consistent with aircraft and boat safety
and training and testing requirements, comply with the observation
objectives described in paragraph (a)(1)(i) of this section.
(iii) Lookout measures for non-impulse sound:
(A) With the exception of vessels less than 65 ft (20 m) in length
and ships that are minimally manned, ships using low-frequency or hull-
mounted mid-frequency active sonar sources associated with anti-
submarine warfare and mine warfare activities at sea will have two
lookouts at the forward position. For the purposes of this rule, low-
frequency active sonar does not include surface towed array
surveillance system low-frequency active sonar.
(B) While using low-frequency or hull-mounted mid-frequency active
sonar sources associated with anti-submarine warfare and mine warfare
activities at sea, ships less than 65 ft (20 m) in length and ships
that are minimally manned will have one lookout at the forward position
of the vessel due to space and manning restrictions.
(C) Ships conducting active sonar activities while moored or at
anchor (including pierside testing or maintenance) will maintain one
lookout.
(D) Surface ships or aircraft conducting high-frequency or non-hull
mounted mid-frequency active sonar activities associated with anti-
submarine warfare and mine warfare activities at sea will have one
lookout.
(iv) Lookout measures for explosives and impulse sound:
(A) Aircraft conducting IEER sonobuoy activities and explosive
sonobuoy exercises will have one lookout.
(B) Surface vessels conducting anti-swimmer grenade activities will
have one lookout.
(C) During general mine countermeasure and neutralization
activities using up to a 20-lb net explosive weight detonation (bin E6
and below), vessels greater than 200 ft (61 m) will have two lookouts,
while vessels less than 200 ft (61 m) or aircraft will have one
lookout.
(D) Mine neutralization activities involving positive control
diver-placed charges using up to a 20-lb net explosive weight
detonation will have two lookouts. The divers placing the charges on
mines will report all marine mammal sightings to their supporting small
boat or Range Safety Officer.
(E) When mine neutralization activities using diver-placed charges
with up to a 20-lb net explosive weight detonation are conducted with a
time-delay firing device, four lookouts will be used. Two lookouts will
be positioned in each of two small rigid hull inflatable boats. When
aircraft are used, the pilot or member of the aircrew will serve as an
additional lookout. The divers placing the charges on mines will report
all marine mammal sightings to their supporting small boat or Range
Safety Officer.
(F) Surface vessels or aircraft conducting small- or medium-caliber
gunnery exercises against a surface target will have one lookout.
(G) Aircraft conducting missile exercises (including rockets)
against surface targets will have one lookout.
(H) Aircraft conducting bombing exercises will have one lookout.
(I) During explosive torpedo testing, one lookout will be used and
positioned in an aircraft.
(J) During sinking exercises, two lookouts will be used. One
lookout will be positioned in an aircraft and one on a surface vessel.
(K) Surface vessels conducting explosive and non-explosive large-
caliber gunnery exercises will have one lookout.
(v) Lookout measures for physical strike and disturbance:
(A) While underway, surface ships will have at least one lookout.
(B) During activities using towed in-water devices, that are towed
from a manned platform, one lookout will be used.
(C) Non-explosive small-, medium-, and large-caliber gunnery
exercises using a surface target will have one lookout.
(D) Non-explosive bombing exercises will have one lookout.
(2) Mitigation zones. The following are protective measures
concerning the implementation of mitigation zones.
(i) Mitigation zones will be measured as the radius from a source
and represent a distance to be monitored.
(ii) Visual detections of marine mammals within a mitigation zone
will be communicated immediately to a watch station for information
dissemination and appropriate action.
(iii) Mitigation zones for non-impulse sound:
(A) When marine mammals are visually detected, the Navy shall
ensure that low-frequency and hull-mounted mid-frequency active sonar
transmission levels are limited to at least 6 dB below normal operating
levels (for sources that can be powered down during the activity) if
any visually detected marine mammals are within 1,000 yd (914 m) of the
source (i.e., the bow).
(B) The Navy shall ensure that low-frequency and hull-mounted mid-
frequency active sonar transmissions are limited to at least 10 dB
below the equipment's normal operating level (for sources that can be
powered down during the activity) if any detected marine mammals are
sighted within 500 yd (457 m) of the source.
(C) The Navy shall ensure that low-frequency and hull-mounted mid-
frequency active sonar transmissions

[[Page 46166]]

(for sources that can be turned off during the activity) are ceased if
any visually detected marine mammals are within 200 yd (183 m) of the
sonar dome. Active transmission will recommence if any one of the
following conditions is 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 and speed and the relative
motion between the animal and the source; the mitigation zone has been
clear from any additional sightings for a period of 30 minutes; the
ship has transited more than 2,000 yd. (1.8 kilometers [km]) beyond the
location of the last sighting; or the ship concludes that dolphins are
deliberately closing in on the ship to ride the ship's bow wave (and
there are no other marine mammal sightings within the mitigation zone).
(D) If the source is not able to be powered down during the
activity (e.g., low-frequency sources within bins LF4 and LF5),
mitigation will involve ceasing active transmission if a marine mammal
is sighted within 200 yd. (183 m). Active transmission will recommence
if any one of the following conditions is 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 and speed and
the relative motion between the animal and the source; the mitigation
zone has been clear from any additional sightings for a period of 30
minutes; or the ship has transited more than 400 yd. (366 m) beyond the
location of the last sighting.
(E) With the exception of activities involving platforms operating
at high altitudes, when marine mammals are visually detected, the Navy
shall ensure that high-frequency and non-hull-mounted mid-frequency
active sonar transmission (for sources that can be turned off during
the activity) is ceased if any visually detected marine mammals are
within 200 yd (183 m) of the source. Active transmission will
recommence if any one of the following conditions is 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 and
speed and the relative motion between the animal and the source, the
mitigation zone has been clear from any additional sightings for a
period of 10 minutes for an aircraft-deployed source, the mitigation
zone has been clear from any additional sightings for a period of 30
minutes for a vessel-deployed source, the vessel or aircraft has
repositioned itself more than 400 yd. (366 m) away from the location of
the last sighting, or the vessel concludes that dolphins are
deliberately closing in to ride the vessel's bow wave (and there are no
other marine mammal sightings within the mitigation zone).
(F) Prior to start up or restart of active sonar, operators shall
check that the mitigation zone radius around the sound source is clear
of marine mammals.
(G) Generally, the Navy shall operate sonar at the lowest
practicable level, not to exceed 235 dB, except as required to meet
tactical training objectives.
(iv) Mitigation zones for explosive and impulse sound:
(A)(1) A mitigation zone with a radius of 600 yd (549 m) shall be
established for IEER sonobuoys (bin E4). Mitigation would include pre-
exercise aerial observation and passive acoustic monitoring, which
would begin 30 minutes before the first source/receiver pair detonation
and continue throughout the duration of the exercise. The pre-exercise
aerial observation would include the time it takes to deploy the
sonobuoy pattern (deployment is conducted by aircraft dropping
sonobuoys in the water). Explosive detonations would cease if a marine
mammal is sighted within the mitigation zone. Detonations would
recommence if any one of the following conditions is met: The animal is
observed exiting the mitigation zone, the animal is thought to have
exited the mitigation zone based on its course and speed and the
relative motion between the animal and the source, or the mitigation
zone has been clear from any additional sightings for a period of 30
minutes.
(2) Passive acoustic monitoring would be conducted with Navy
assets, such as sonobuoys, already participating in the activity. These
assets would only detect vocalizing marine mammals within the frequency
bands monitored by Navy personnel. Passive acoustic detections would
not provide range or bearing to detected animals, and therefore cannot
provide locations of these animals. Passive acoustic detections would
be reported to lookouts posted in aircraft and on vessels in order to
increase vigilance of their visual observation.
(B)(1) A mitigation zone with a radius of 350 yd (320 m) shall be
established for explosive sonobuoys using 0.5-2.5 lb net explosive
weight (bin E3). Mitigation would include pre-exercise aerial
monitoring during deployment of the field of sonobuoy pairs (typically
up to 20 minutes) and continuing throughout the duration of the
exercise within a mitigation zone of 350 yd (320 m) around an explosive
sonobuoy. Explosive detonations would cease if a marine mammal is
sighted within the mitigation zone. Detonations would recommence if any
one of the following conditions is met: The animal is observed exiting
the mitigation zone, the animal is thought to have exited the
mitigation zone based on its course and speed and the relative motion
between the animal and the source, or the mitigation zone has been
clear from any additional sightings for a period of 10 minutes.
(2) Passive acoustic monitoring would also be conducted with Navy
assets, such as sonobuoys, already participating in the activity. These
assets would only detect vocalizing marine mammals within the frequency
bands monitored by Navy personnel. Passive acoustic detections would
not provide range or bearing to detected animals, and therefore cannot
provide locations of these animals. Passive acoustic detections would
be reported to lookouts posted in aircraft in order to increase
vigilance of their visual observation.
(C) A mitigation zone with a radius of 200 yd (183 m) shall be
established for anti-swimmer grenades (bin E2). Mitigation would
include visual observation from a small boat immediately before and
during the exercise within a mitigation zone of 200 yd (183 m) around
an anti-swimmer grenade. Explosive detonations would cease if a marine
mammal is sighted within the mitigation zone. Detonations would
recommence if any one of the following conditions is met: The animal is
observed exiting the mitigation zone, the animal is thought to have
exited the mitigation zone based on its course and speed and the
relative motion between the animal and the source, the mitigation zone
has been clear from any additional sightings for a period of 30
minutes, or the activity has been repositioned more than 400 yd (366 m)
away from the location of the last sighting.
(D) A mitigation zone ranging from 350 yd (320 m) to 800 yd (732
m), dependent on charge size and if the activity involves the use of
diver-placed charges, shall be established for mine countermeasure and
neutralization activities using positive control firing devices.
Mitigation zone distances are specified for charge size in the
following table.

[[Page 46167]]

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
General mine countermeasure and neutralization activities using Mine countermeasure and neutralization activities using diver
positive control firing devices \1\ placed charges under positive control \2\
-----------------------------------------------------------------------------------------------------------------------------------
Charge size net explosive weight (bins) Predicted Predicted Predicted Predicted Predicted Predicted
average range average range maximum range Recommended average range average range maximum range Recommended
to TTS to PTS to PTS mitigation zone to TTS to PTS to PTS mitigation zone
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2.5-5 lb. (1.2-2.3 kg) (E4)................................. 434 yd 197 yd 563 yd 600 yd 545 yd 169 yd 301 yd 350 yd.
(474 m) (180 m) (515 m) (549 m) (498 m) (155 m) (275 m) (320 m).
5-10 lb. (2.7-4.5 kg) (E5).................................. 525 yd 204 yd 649 yd 800 yd 587 yd 203 yd 464 yd 500 yd.
(480 m) (187 m) (593 m) (732 m) (537 m) (185 m) (424 m) (457 m).
>10-20 lb. (5-9.1 kg) (E6).................................. 766 yd 288 yd 648 yd 800 yd 647 yd 232 yd 469 yd 500 yd.
(700 m) (263 m) (593 m) (732 m) (592 m) (212 m) (429 m) (457 m).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
PTS: permanent threshold shift; TTS: temporary threshold shift.
\1\ These mitigation zones are applicable to all mine countermeasure and neutralization activities conducted in all locations specified in Chapter 2 of the Navy's LOA application.
\2\ These mitigation zones are only applicable to mine countermeasure and neutralization activities involving the use of diver placed charges. These activities are conducted in shallow-water
and the mitigation zones are based only on the functional hearing groups with species that occur in these areas (mid-frequency cetaceans and sea turtles).

(1) During general mine countermeasure and neutralization
activities, mitigation would include visual observation from one or
more small boats or aircraft beginning 30 minutes before, during, and
30 minutes after (when helicopters are not involved in the activity) or
10 minutes before, during, and 10 minutes after (when helicopters are
involved in the activity) the completion of the exercise within the
mitigation zones around the detonation site.
(2) For activities involving diver-placed charges, visual
observation would be conducted by either two small boats, or one small
boat in combination with one helicopter. Boats would position
themselves near the mid-point of the mitigation zone radius (but always
outside the detonation plume radius and human safety zone) and travel
in a circular pattern around the detonation location. When using two
boats, each boat would be positioned on opposite sides of the
detonation location, separated by 180 degrees. If used, helicopters
would travel in a circular pattern around the detonation location.
(3) For both general and diver-placed positive control mine
countermeasure and neutralization activities, explosive detonations
will cease if a marine mammal is sighted within the mitigation zone.
Detonations will recommence if any one of the following conditions is
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 and speed and the relative motion between the animal and the
source, the mitigation zone has been clear from any additional
sightings for a period of 30 minutes, when helicopters are not involved
in the activity or the mitigation zone has been clear from any
additional sightings for a period of 10 minutes when helicopters are
involved in the activity.
(E) A mitigation zone with a radius of 1,000 yd (914 m) shall be
established for mine countermeasure and neutralization activities using
diver-placed time-delay firing devices (bin E6). Mine neutralization
activities involving diver-placed charges would not include time-delay
longer than 10 minutes. Mitigation would include visual observation
from small boats or aircraft commencing 30 minutes before, during, and
until 30 minutes after the completion of the exercise within a
mitigation zone of 1,000 yd (914 m) around the detonation site. During
activities using time-delay firing devices involving up to a 20 lb net
explosive weight charge, visual observation will take place using two
small boats. Fuse initiation would recommence if any one of the
following conditions is met: The animal is observed exiting the
mitigation zone, the animal is thought to have exited the mitigation
zone based on its course and speed and the relative motion between the
animal and the source, or the mitigation zone has been clear from any
additional sightings for a period of 30 minutes.
(1) Survey boats would position themselves near the mid-point of
the mitigation zone radius (but always outside the detonation plume
radius/human safety zone) and travel in a circular pattern around the
detonation location. One lookout from each boat would look inward
toward the detonation site and the other lookout would look outward
away from the detonation site. When using two small boats, each boat
would be positioned on opposite sides of the detonation location,
separated by 180 degrees. If available for use, helicopters would
travel in a circular pattern around the detonation location.
(2) [Reserved]
(F) A mitigation zone with a radius of 200 yd (183 m) shall be
established for small- and medium-caliber gunnery exercises with a
surface target (bin E2). Mitigation would include visual observation
from a vessel or aircraft immediately before and during the exercise
within a mitigation zone of 200 yd (183 m) around the intended impact
location. Vessels would observe the mitigation zone from the firing
position. When aircraft are firing, the aircrew would maintain visual
watch of the mitigation zone during the activity. Firing would cease if
a marine mammal is sighted within the mitigation zone. Firing would
recommence if any one of the following conditions is met: The animal is
observed exiting the mitigation zone, the animal is thought to have
exited the mitigation zone based on its course and speed and the
relative motion between the animal and the source, the mitigation zone
has been clear from any additional sightings for a period of 10 minutes
for a firing aircraft, the mitigation zone has been clear from any
additional sightings for a period of 30 minutes for a firing vessel, or
the intended target location has been repositioned more than 400 yd
(366 m) away from the location of the last sighting.
(G) A mitigation zone with a radius of 600 yd (549 m) shall be
established for large-caliber gunnery exercises with a surface target
(bin E5). Mitigation would include visual observation from a ship
immediately before and during the exercise within a mitigation zone of
600 yd (549 m) around the intended impact location. Ships would observe
the mitigation zone from the firing position. Firing would cease if a
marine mammal is sighted within the mitigation zone. Firing would
recommence if any one of the following conditions is met: The animal is
observed exiting the mitigation zone, the animal is thought to

[[Page 46168]]

have exited the mitigation zone based on its course and speed and the
relative motion between the animal and the source, or the mitigation
zone has been clear from any additional sightings for a period of 30
minutes.
(H) A mitigation zone with a radius of 900 yd (823 m) around the
deployed target shall be established for missile exercises involving
aircraft firing up to 250 lb net explosive weight using and a surface
target (bin E9). When aircraft are firing, mitigation would include
visual observation by the aircrew or supporting aircraft prior to
commencement of the activity within a mitigation zone of 900 yd (823 m)
around the deployed target. Firing would recommence if any one of the
following conditions is met: The animal is observed exiting the
mitigation zone, the animal is thought to have exited the mitigation
zone based on its course and speed and the relative motion between the
animal and the source, or the mitigation zone has been clear from any
additional sightings for a period of 10 minutes or 30 minutes
(depending on aircraft type).
(I) A mitigation zone with a radius of 2,000 yd (1.8 km) shall be
established for missile exercises involving aircraft firing >250 to 500
lb net explosive weight using and a surface target (bin E10). When
aircraft are firing, mitigation would include visual observation by the
aircrew prior to commencement of the activity within a mitigation zone
of 2,000 yd (1.8 km) around the intended impact location. Firing would
cease if a marine mammal is sighted within the mitigation zone. Firing
would recommence if any one of the following conditions is met: The
animal is observed exiting the mitigation zone, the animal is thought
to have exited the mitigation zone based on its course and speed and
the relative motion between the animal and the source, or the
mitigation zone has been clear from any additional sightings for a
period of 10 minutes or 30 minutes (depending on aircraft type).
(J) A mitigation zone with a radius of 2,500 yd (2.3 km) shall be
established for bombing exercises (bin E12). Mitigation would include
visual observation from the aircraft immediately before the exercise
and during target approach within a mitigation zone of 2,500 yd (2.3
km) around the intended impact location. Bombing would cease if a
marine mammal is sighted within the mitigation zone. Bombing would
recommence if any one of the following conditions is met: The animal is
observed exiting the mitigation zone, the animal is thought to have
exited the mitigation zone based on its course and speed and the
relative motion between the animal and the source, or the mitigation
zone has been clear from any additional sightings for a period of 10
minutes.
(K)(1) A mitigation zone with a radius of 2,100 yd (1.9 km) shall
be established for torpedo (explosive) testing (except for aircraft
operating at high altitudes) (bin E11). Mitigation would include visual
observation by aircraft immediately before, during, and after the
exercise within a mitigation zone of 2,100 yd (1.9 km) around the
intended impact location. Firing would cease if a marine mammal is
sighted within the mitigation zone. Firing would recommence if any one
of the following conditions is met: The animal is observed exiting the
mitigation zone, the animal is thought to have exited the mitigation
zone based on its course and speed and the relative motion between the
animal and the source, or the mitigation zone has been clear from any
additional sightings for a period of 10 minutes or 30 minutes
(depending on aircraft type).
(2) In addition to visual observation, passive acoustic monitoring
would be conducted with Navy assets, such as passive ships sonar
systems or sonobuoys, already participating in the activity. Passive
acoustic observation would be accomplished through the use of remote
acoustic sensors or expendable sonobuoys, or via passive acoustic
sensors on submarines when they participate in the proposed action.
These assets would only detect vocalizing marine mammals within the
frequency bands monitored by Navy personnel. Passive acoustic
detections would not provide range or bearing to detected animals, and
therefore cannot provide locations of these animals. Passive acoustic
detections would be reported to the lookout posted in the aircraft in
order to increase vigilance of the visual observation and to the person
in control of the activity for their consideration in determining when
the mitigation zone is free of visible marine mammals.
(L) A mitigation zone with a radius of 2.5 nautical miles around
the target ship hulk shall be established for sinking exercises (bin
E12). Mitigation would include aerial observation beginning 90 minutes
before the first firing, visual observations from vessels throughout
the duration of the exercise, and both aerial and vessel observation
immediately after any planned or unplanned breaks in weapons firing of
longer than 2 hours. Prior to conducting the exercise, the Navy would
review remotely sensed sea surface temperature and sea surface height
maps to aid in deciding where to release the target ship hulk.
(1) The Navy would also monitor using passive acoustics during the
exercise. Passive acoustic monitoring would be conducted with Navy
assets, such as passive ships sonar systems or sonobuoys, already
participating in the activity. These assets would only detect
vocalizing marine mammals within the frequency bands monitored by Navy
personnel. Passive acoustic detections would not provide range or
bearing to detected animals, and therefore cannot provide locations of
these animals. Passive acoustic detections would be reported to
lookouts posted in aircraft and on vessels in order to increase
vigilance of their visual observation. Lookouts will also increase
observation vigilance before the use of torpedoes or unguided ordnance
with a net explosive weight of 500 lb or greater, or if the Beaufort
sea state is a 4 or above.
(2) The exercise would cease if a marine mammal is sighted within
the mitigation zone. The exercise would recommence if any one of the
following conditions is met: The animal is observed exiting the
mitigation zone, the animal is thought to have exited the mitigation
zone based on its course and speed and the relative motion between the
animal and the source, or the mitigation zone has been clear from any
additional sightings for a period of 30 minutes. Upon sinking the
vessel, the Navy would conduct post-exercise visual observation of the
mitigation zone for 2 hours (or until sunset, whichever comes first).
(M) A mitigation zone with a radius of 70 yd (64 m) within 30
degrees on either side of the gun target line on the firing side of the
vessel for explosive and non-explosive large-caliber gunnery exercises
conducted from a ship. Firing would cease if a marine mammal is sighted
within the mitigation zone. Firing would recommence if any one of the
following conditions is met: The animal is observed exiting the
mitigation zone, the animal is thought to have exited the mitigation
zone based on its course and speed and the relative motion between the
animal and the source, the mitigation zone has been clear from any
additional sightings for a period of 30 minutes, or the vessel has
repositioned itself more than 140 yd (128 m) away from the location of
the last sighting.
(v) Mitigation zones for vessels and in-water devices:
(A) A mitigation zone of 500 yd (457 m) for observed whales and 200
yd (183 m) for all other marine mammals (except bow riding dolphins)
shall be

[[Page 46169]]

established for all vessel movement, providing it is safe to do so.
(B) A mitigation zone of 250 yd (229 m) shall be established for
all towed in-water devices that are towed from a manned platform,
providing it is safe to do so.
(vi) Mitigation zones for non-explosive practice munitions:
(A) A mitigation zone of 200 yd (183 m) shall be established for
non-explosive small-, medium-, and large-caliber gunnery exercises
using a surface target. Mitigation would include visual observation
immediately before and during the exercise within a mitigation zone of
200 m around the intended impact location. Firing would cease if a
marine mammal is visually detected within the mitigation zone. Firing
would recommence if any one of the following conditions are met: The
animal is observed exiting the mitigation zone, the animal is thought
to have exited the mitigation zone based on its course and speed and
the relative motion between the animal and the source, the mitigation
zone has been clear from any additional sightings for a period of 10
minutes for a firing aircraft, the mitigation zone has been clear from
any additional sightings for a period of 30 minutes for a firing
vessel, or the intended target location has been repositioned more than
400 yd (366 m) away from the location of the last sighting and the
animal's estimated course direction.
(B) A mitigation zone of 1,000 yd (914 m) shall be established for
non-explosive bombing exercises. Mitigation would include visual
observation from the aircraft immediately before the exercise and
during target approach within a mitigation zone of 1000 yd (914 m)
around the intended impact location. Bombing would cease if a marine
mammal is visually detected within the mitigation zone. Bombing would
recommence if any one of the following conditions are met: The animal
is observed exiting the mitigation zone, the animal is thought to have
exited the mitigation zone based on its course and speed and the
relative motion between the animal and the source, or the mitigation
zone has been clear from any additional sightings for a period of 10
minutes.
(3) Stranding Response Plan:
(i) The Navy shall abide by the letter of the ``Stranding Response
Plan for Major Navy Training Exercises in the MITT Study Area,'' to
include the following measures:
(A) Shutdown Procedures--When an Uncommon Stranding Event (USE--
defined in Sec. 218.91) occurs during a Major Training Exercise (MTE)
in the MITT Study Area, the Navy shall implement the procedures
described below.
(1) The Navy shall implement a shutdown (as defined Sec. 218.91)
when advised by a NMFS Office of Protected Resources Headquarters
Senior Official designated in the MITT Study Area Stranding
Communication Protocol that a USE involving live animals has been
identified and that at least one live animal is located in the water.
NMFS and the Navy will maintain a dialogue, as needed, regarding the
identification of the USE and the potential need to implement shutdown
procedures.
(2) Any shutdown in a given area shall remain in effect in that
area until NMFS advises the Navy that the subject(s) of the USE at that
area die or are euthanized, or that all live animals involved in the
USE at that area have left the area (either of their own volition or
herded).
(3) If the Navy finds an injured or dead animal floating at sea
during an MTE, the Navy shall notify NMFS immediately or as soon as
operational security considerations allow. The Navy shall provide NMFS
with species or description of the animal(s), the condition of the
animal(s), including carcass condition if the animal(s) is/are dead,
location, time of first discovery, observed behavior (if alive), and
photo or video (if available). Based on the information provided, NFMS
will determine if, and advise the Navy whether a modified shutdown is
appropriate on a case-by-case basis.
(4) In the event, following a USE, that qualified individuals are
attempting to herd animals back out to the open ocean and animals are
not willing to leave, or animals are seen repeatedly heading for the
open ocean but turning back to shore, NMFS and the Navy shall
coordinate (including an investigation of other potential anthropogenic
stressors in the area) to determine if the proximity of mid-frequency
active sonar training activities or explosive detonations, though
farther than 14 nautical miles from the distressed animal(s), is likely
contributing to the animals' refusal to return to the open water. If
so, NMFS and the Navy will further coordinate to determine what
measures are necessary to improve the probability that the animals will
return to open water and implement those measures as appropriate.
(5) Within 72 hours of NMFS notifying the Navy of the presence of a
USE, the Navy shall provide available information to NMFS (per the MITT
Study Area Communication Protocol) regarding the location, number and
types of acoustic/explosive sources, direction and speed of units using
mid-frequency active sonar, and marine mammal sightings information
associated with training activities occurring within 80 nautical miles
(148 km) and 72 hours prior to the USE event. Information not initially
available regarding the 80-nautical miles (148-km), 72-hour period
prior to the event will be provided as soon as it becomes available.
The Navy will provide NMFS investigative teams with additional relevant
unclassified information as requested, if available.
(b) [Reserved]

Sec. 218.95 Requirements for monitoring and reporting.

(a) As outlined in the MITT Study Area Stranding Communication
Plan, the Holder of the Authorization must notify NMFS immediately (or
as soon as operational security considerations allow) if the specified
activity identified in Sec. 218.90 is thought to have resulted in the
mortality or injury of any marine mammals, or in any take of marine
mammals not identified in Sec. 218.91.
(b) The Holder of the LOA must conduct all monitoring and required
reporting under the LOA, including abiding by the MITT Monitoring
Project Description.
(c) General notification of injured or dead marine mammals. Navy
personnel shall ensure that NMFS (regional stranding coordinator) is
notified immediately (or as soon as operational security considerations
allow) if an injured or dead marine mammal is found during or shortly
after, and in the vicinity of, an Navy training or testing activity
utilizing mid- or high-frequency active sonar, or underwater explosive
detonations. The Navy shall provide NMFS with species or description of
the animal(s), the condition of the animal(s) (including carcass
condition if the animal is dead), location, time of first discovery,
observed behaviors (if alive), and photo or video (if available). The
Navy shall consult the Stranding Response Plan to obtain more specific
reporting requirements for specific circumstances.
(d) Vessel strike. In the event that a Navy vessel strikes a whale,
the Navy shall do the following:
(1) Immediately report to NMFS (pursuant to the established
Communication Protocol) the:
(i) Species identification if known;
(ii) Location (latitude/longitude) of the animal (or location of
the strike if the animal has disappeared);
(iii) Whether the animal is alive or dead (or unknown); and
(iv) The time of the strike.

[[Page 46170]]

(2) As soon as feasible, the Navy shall report to or provide to
NMFS, the:
(i) Size, length, and description (critical if species is not
known) of animal;
(ii) An estimate of the injury status (e.g., dead, injured but
alive, injured and moving, blood or tissue observed in the water,
status unknown, disappeared, etc.);
(iii) Description of the behavior of the whale during event,
immediately after the strike, and following the strike (until the
report is made or the animal is no long sighted);
(iv) Vessel class/type and operation status;
(v) Vessel length
(vi) Vessel speed and heading; and
(vii) To the best extent possible, obtain
(3) Within 2 weeks of the strike, provide NMFS:
(i) A detailed description of the specific actions of the vessel in
the 30-minute timeframe immediately preceding the strike, during the
event, and immediately after the strike (e.g., the speed and changes in
speed, the direction and changes in the direction, other maneuvers,
sonar use, etc., if not classified); and
(ii) A narrative description of marine mammal sightings during the
event and immediately after, and any information as to sightings prior
to the strike, if available; and
(iii) Use established Navy shipboard procedures to make a camera
available to attempt to capture photographs following a ship strike.
(e) Annual MITT monitoring program report. (1) The Navy shall
submit an annual report describing the implementation and results of
the MITT Monitoring Program, described in Sec. 218.95. Data standards
will be consistent to the extent appropriate across range complexes and
study areas to allow for comparison in different geographic locations.
Although additional information will be gathered, the protected species
observers collecting marine mammal data pursuant to the MITT Monitoring
Program shall, at a minimum, provide the same marine mammal observation
data required in this section.
(2) As an alternative, the Navy may submit a multi-range complex
annual monitoring plan report to fulfill this requirement. Such a
report would describe progress of knowledge made with respect to
monitoring plan study questions across multiple Navy ranges associated
with the ICMP. Similar study questions shall be treated together so
that progress on each topic shall 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. The report shall be submitted either 90 days after the
calendar year, or 90 days after the conclusion of the monitoring year
date to be determined by the Adaptive Management process.
(f) Sonar exercise notification. The Navy shall submit to NMFS
(specific contact information to be provided in the LOA) either an
electronic (preferably) or verbal report within 15 calendar days after
the completion of any major exercise indicating:
(1) Location of the exercise.
(2) Beginning and end dates of the exercise.
(3) Type of exercise.
(g) Annual MITT exercise and testing report. The Navy shall submit
preliminary reports detailing the status of authorized sound sources
within 21 days after the anniversary of the date of issuance of the
LOA. The Navy shall submit a detailed report 3 months after the
anniversary of the date of issuance of the LOA. The detailed annual
report shall contain information on Major Training Exercises (MTE),
Sinking Exercise (SINKEX) events, and a summary of sound sources used,
as described below. 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 detailed report shall contain
information identified in Sec. 218.95(e)(1) and (2).
(1) Major Training Exercises/SINKEX:
(i) This section shall contain the reporting requirements for
Coordinated and Strike Group exercises and SINKEX. Coordinated and
Strike Group Major Training Exercises include:
(A) Joint Multi-Strike Group Exercise (Valiant Shield).
(B) Joint Expeditionary Exercise
(ii) Exercise information for each MTE:
(A) Exercise designator.
(B) Date that exercise began and ended.
(C) Location (operating area).
(D) Number of items or hours (per the LOA) of each sound source bin
(impulsive and non-impulsive) used in the exercise.
(E) Number and types of vessels, aircraft, etc., participating in
exercise.
(F) Individual marine mammal sighting info for each sighting during
each MTE:
(1) Date/time/location of sighting.
(2) Species (if not possible, indication of whale/dolphin).
(3) Number of individuals.
(4) Initial detection sensor.
(5) Indication of specific type of platform the observation was
made from (including, for example, what type of surface vessel or
testing platform).
(6) Length of time observers maintained visual contact with marine
mammal(s).
(7) Sea state.
(8) Visibility.
(9) Sound source in use at the time of sighting.
(10) Indication of whether animal is <200 yd, 200 to 500 yd, 500 to
1,000 yd, 1,000 to 2,000 yd, or >2,000 yd from sound source.
(11) Mitigation Implementation--Whether operation of sonar sensor
was delayed, or sonar was powered or shut down, and how long the delay
was; or whether navigation was changed or delayed.
(12) If source in use is a hull-mounted sonar, relative bearing of
animal from ship, and estimation of animal's motion relative to ship
(opening, closing, parallel).
(13) Observed behavior--Watchstanders shall report, in plain
language and without trying to categorize in any way, the observed
behavior of the animal(s) (such as animal closing to bow ride,
paralleling course/speed, floating on surface and not swimming, etc.)
and if any calves present.
(iii) An evaluation (based on data gathered during all of the MTEs)
of the effectiveness of mitigation measures designed to minimize the
received level to which marine mammals may be exposed. This evaluation
shall identify the specific observations that support any conclusions
the Navy reaches about the effectiveness of the mitigation.
(iv) Exercise information for each SINKEX:
(A) List of the vessels and aircraft involved in the SINKEX.
(B) Location (operating area).
(C) Chronological list of events with times, including time of
sunrise and sunset, start and stop time of all marine species surveys
that occur before, during, and after the SINKEX, and ordnance used.
(D) Visibility and/or weather conditions, wind speed, cloud cover,
etc. throughout exercise if it changes.
(E) Aircraft used in the surveys, flight altitude, and flight speed
and the area covered by each of the surveys, given in coordinates, map,
or square miles.
(F) Passive acoustic monitoring details (number of sonobuoys, area,
detections of biologic activity, etc.).
(G) Individual marine mammal sighting info for each sighting that
required mitigation to be implemented:
(1) Date/time/location of sighting.

[[Page 46171]]

(2) Species (if not possible, indication of whale/dolphin).
(3) Number of individuals.
(4) Initial detection sensor.
(5) Indication of specific type of platform the observation was
made from (including, for example, what type of surface vessel or
platform).
(6) Length of time observers maintained visual contact with marine
mammal(s).
(7) Sea state.
(8) Visibility.
(9) Indication of whether animal is <200 yd, 200-500 yd, 500-1,000
yd, 1,000-2,000 yd, or >2,000 yd from the target.
(10) Mitigation implementation--Whether the SINKEX was stopped or
delayed and length of delay.
(11) Observed behavior--Watchstanders shall report, in plain
language and without trying to categorize in any way, the observed
behavior of the animals (such as animal closing to bow ride,
paralleling course/speed, floating on surface and not swimming, etc.),
and if any calves present.
(H) List of the ordnance used throughout the SINKEX and net
explosive weight (NEW) of each weapon and the combined NEW.
(2) Summary of sources used. (i) This section shall include the
following information summarized from the authorized sound sources used
in all training and testing events:
(A) Total annual or quantity (per the LOA) of each bin of sonar or
other non-impulsive source;
(B) Total annual expended/detonated rounds (missiles, bombs, etc.)
for each explosive bin; and
(C) Improved Extended Echo-Ranging System (IEER)/sonobuoy summary,
including:
(1) Total expended/detonated rounds (buoys).
(2) Total number of self-scuttled IEER rounds.
(3) Geographic information presentation. The reports shall present
an annual (and seasonal, where practical) depiction of training
exercises and testing bin usage geographically across the Study Area.
(h) Five-year close-out exercise and testing report.--This report
will be included as part of the 2020 annual exercise or testing report.
This report will provide the annual totals for each sound source bin
with a comparison to the annual allowance and the 5-year total for each
sound source bin with a comparison to the 5-year allowance.
Additionally, if there were any changes to the sound source allowance,
this report will include a discussion of why the change was made and
include the analysis to support how the change did or did not result in
a change in the FEIS and final rule determinations. The report will be
submitted 3 months after the expiration of the rule. NMFS will submit
comments on the draft close-out report, if any, within 3 months of
receipt. The report will be considered final after the Navy has
addressed NMFS' comments, or 3 months after the submittal of the draft
if NMFS does not provide comments.

Sec. 218.96 Applications for Letters of Authorization.

To incidentally take marine mammals pursuant to the regulations in
this subpart, the U.S. citizen (as defined by Sec. 216.106 of this
chapter) conducting the activity identified in Sec. 218.90(c) (the
U.S. Navy) must apply for and obtain either an initial LOA in
accordance with Sec. 218.97 or a renewal under Sec. 218.98.

Sec. 218.97 Letters of Authorization.

(a) An LOA, unless suspended or revoked, will be valid for a period
of time not to exceed the period of validity of this subpart.
(b) The LOA will set forth:
(1) Permissible methods and extent of incidental taking;
(2) Means of effecting the least practicable adverse impact on the
species, its habitat, and on the availability of the species for
subsistence uses (i.e., mitigation); and
(3) Requirements for mitigation, monitoring and reporting.
(c) Issuance of the LOA will be based on a determination that the
total number of marine mammals taken by the activity as a whole will
have no more than a negligible impact on the affected species or stock
of marine mammal(s).

Sec. 218.98 Renewals and modifications of Letters of Authorization.

(a) A Letter of Authorization issued under Sec. Sec. 216.106 and
218.97 of this chapter for the activity identified in Sec. 218.90(c)
will be renewed or modified upon request of the applicant, provided
that:
(1) The proposed specified activity and mitigation, monitoring, and
reporting measures, as well as the anticipated impacts, are within the
scope of those described and analyzed for these regulations (excluding
changes made pursuant to the adaptive management provision of this
chapter), and;
(2) NMFS determines that the mitigation, monitoring, and reporting
measures required by the previous LOA under these regulations were
implemented.
(b) For LOA modification or renewal requests by the applicant that
include changes to the activity or the mitigation, monitoring, or
reporting (excluding changes made pursuant to the adaptive management
provision of this chapter) that do not change the findings made for the
regulations or result in no more than a minor change in the total
estimated number of takes (or distribution by species or years). NMFS
may publish a notice of proposed LOA in the Federal Register, including
the associated analysis illustrating the change, and solicit public
comment before issuing the LOA.
(c) An LOA issued under Sec. Sec. 216.106 and 218.97 of this
chapter for the activity identified in Sec. 218.94 of this chapter may
be modified by NMFS under the following circumstances:
(1) Adaptive management. NMFS may modify (including augmenting,
changing, or reducing) the existing mitigation, monitoring, or
reporting measures (after consulting with the Navy regarding the
practicability of the modifications) 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, and reporting measures in an LOA:
(A) Results from 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 these regulations or
subsequent LOA.
(ii) If, through adaptive management, the modifications to the
mitigation, monitoring, or reporting measures are substantial, NMFS
would publish a notice of proposed LOA in the Federal Register and
solicit public comment.
(2) Emergencies. 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 Sec. 218.92(c), an LOA may be modified
without prior notification and an opportunity for public comment.
Notification would be published in the Federal Register within 30 days
of the action.

[FR Doc. 2015-18633 Filed 7-31-15; 8:45 am]
BILLING CODE 3510-22-P

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.