Taking and Importing Marine Mammals; U.S. Navy's Research, Development, Test, and Evaluation Activities Within the Naval Sea Systems Command Naval Undersea Warfare Center Keyport Range Complex, 32264-32305 [E9-15839]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 74, Number 128 (Tuesday, July 7, 2009)]
[Proposed Rules]
[Pages 32264-32305]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-15839]



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Part III





Department of Commerce





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National Oceanic and Atmospheric Administration



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50 CFR Part 218



Taking and Importing Marine Mammals; U.S. Navy's Research, Development, 
Test, and Evaluation Activities Within the Naval Sea Systems Command 
Naval Undersea Warfare Center Keyport Range Complex; Proposed Rule

Federal Register / Vol. 74, No. 128 / Tuesday, July 7, 2009 / 
Proposed Rules

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 218

RIN 0648-AX11


Taking and Importing Marine Mammals; U.S. Navy's Research, 
Development, Test, and Evaluation Activities Within the Naval Sea 
Systems Command Naval Undersea Warfare Center Keyport Range Complex

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

ACTION: Proposed rule; request for comments.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) for 
authorization to take marine mammals incidental to the Navy's Research, 
Development, Test, and Evaluation (RDT&E) activities within the Naval 
Sea System Command (NAVSEA) Naval Undersea Warfare Center (NUWC) 
Keyport Range Complex and the associated proposed extensions for the 
period of September 2009 through September 2014. Pursuant to the Marine 
Mammal Protection Act (MMPA), NMFS is proposing regulations to govern 
that take and requesting information, suggestions, and comments on 
these proposed regulations.

DATES: Comments and information must be received no later than August 
6, 2009.

ADDRESSES: You may submit comments, identified by 0648-AX11, by any one 
of the following methods:
     Electronic Submissions: Submit all electronic public 
comments via the Federal eRulemaking Portal https://www.regulations.gov
     Hand delivery or mailing of paper, disk, or CD-ROM: 
Comments should be addressed to Michael Payne, Chief, Permits, 
Conservation and Education Division, Office of Protected Resources, 
National Marine Fisheries Service, 1315 East-West Highway, Silver 
Spring, MD 20910-3225.
    Instructions: All comments received are a part of the public record 
and will generally be posted to https://www.regulations.gov without 
change. All personal identifying information (for example, name, 
address, etc.) voluntarily submitted by the commenter may be publicly 
accessible. Do not submit Confidential Business Information or 
otherwise sensitive or protected information.
    NMFS will accept anonymous comments (enter N/A in the required 
fields if you wish to remain anonymous). Attachments to electronic 
comments will be accepted in Microsoft Word, Excel, WordPerfect, or 
Adobe PDF file formats only.

FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected 
Resources, NMFS, (301) 713-2289, ext. 137.

SUPPLEMENTARY INFORMATION:

Availability

    A copy of the Navy's application may be obtained by writing to the 
address specified above (see ADDRESSES), telephoning the contact listed 
above (see FOR FURTHER INFORMATION CONTACT), or visiting the internet 
at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm. The Navy's 
Draft Environmental Impact Statement (DEIS) for the Keyport Range 
Complex RDT&E and range extension activities was published on September 
12, 2008, and may be viewed at https://www-keyport.kpt.nuwc.navy.mil. 
NMFS participated in the development of the Navy's DEIS as a 
cooperating agency under the National Environmental Policy Act (NEPA).

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce (Secretary) to allow, upon request, 
the incidental, but not intentional taking of marine mammals by U.S. 
citizens who engage in a specified activity (other than commercial 
fishing) during periods of not more than five consecutive years each if 
certain findings are made and regulations are issued or, if the taking 
is limited to harassment, notice of a proposed authorization is 
provided to the public for review.
    Authorization 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, and if the permissible methods of taking 
and requirements pertaining to the mitigation, monitoring and reporting 
of such taking 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) (Public Law 
108-136) removed the ``small numbers'' and ``specified geographical 
region'' limitations in sections 101(a)(5)(A) and (D) 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 May 15, 2008, NMFS received an application from the Navy 
requesting authorization for the take of 5 species of marine mammals 
incidental to the RDT&E activities within the NAVSEA NUWC Keyport Range 
Complex Extension over the course of 5 years. These RDT&E activities 
are classified as military readiness activities. On April 29, 2009, 
NMFS received additional information and clarification on the Navy's 
proposed NAVSEA NUWC Keyport Range Complex Extension RDT&E activities. 
The Navy states that these RDT&E activities may cause various impacts 
to marine mammal species in the proposed action area. The Navy requests 
an authorization to take individuals of these marine mammals by Level B 
Harassment. Please refer to Tables 6-23, 6-24, 6-25, and 6-26 of the 
Navy's Letter of Authorization (LOA) application for detailed 
information of the potential marine mammal exposures from the RDT&E 
activities in the Keyport Range Complex Extension per year. However, 
due to the proposed mitigation and monitoring measures and standard 
range operating procedures in place, NMFS estimates that the take of 
marine mammals is likely to be lower than the amount requested. NMFS 
does not expect any marine mammals to be killed or injured as a result 
of the Navy's proposed activities, and NMFS is not proposing to 
authorize any injury or mortality incidental to the Navy's proposed 
RDT&E activities within the Keyport Range Complex Extension.

Background of Navy Request

    The Navy proposes to extend the NAVSEA NUWC Keyport Range Complex 
in Washington State. The NAVSEA NUWC Keyport Range Complex has the 
infrastructure to support RDT&E activities. Centrally located within 
Washington State, the

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NAVSEA NUWC Keyport Range Complex has extensive existing range assets 
and capabilities. The NAVSEA NUWC Keyport Range Complex is composed of 
Keyport Range Site, Dabob Bay Range Complex (DBRC) Site, and Quinault 
Underwater Tracking Range (QUTR) Site (see Figure 1-1 of the Navy's LOA 
application).
    The goal of the Proposed Action is to extend the operational areas 
of each range site. Extending the Range Complex operating areas outside 
existing range boundaries will allow the Navy to support existing and 
future range activities including evolving manned and unmanned vehicle 
program needs in multiple marine environments. With the proposed 
extension of the Keyport and QUTR range sites, the range sites could 
support more activities, which include increases in the numbers of 
tests and days of testing. No additional operational tempo is proposed 
for the DBRC Site. Existing and evolving range activities applied for 
in this LOA application include RDT&E and training of system 
capabilities such as guidance, control, and sensor accuracy of manned 
and unmanned vehicles in multiple marine environments (e.g., differing 
depths, salinity levels, temperatures, sea states, etc.).
    The range extension is necessary to provide adequate testing area 
and volume (i.e., surface area and water depth) in multiple marine 
environments. The extension enables the NUWC Keyport to fulfill its 
mission of providing test and evaluation services in both surrogate and 
simulated war-fighting environments for emerging manned and unmanned 
vehicle program activities. Within the NAVSEA NUWC Keyport Range 
Complex Extension, the NUWC Keyport activities include testing, 
training, and evaluation of systems capabilities such as guidance, 
control, and sensor accuracy of manned and unmanned vehicles in 
multiple marine environments (e.g., differing depths, salinity levels, 
temperatures, sea states, etc.).
    NUWC Keyport consists of 340 acres (138 hectares [ha]) on the 
shores of Liberty Bay and Port Orchard Reach (a.k.a. Port Orchard 
Narrows), and is located adjacent to the town of Keyport, due west of 
Seattle. NUWC Keyport, a part of NAVSEA, is the center for integrated 
undersea warfare systems dependability, integrated mine and undersea 
warfare supportability, and undersea vehicle maintenance and 
engineering. It provides test and evaluation, in-service engineering, 
maintenance, Fleet readiness, and industrial-based support for undersea 
warfare systems, including RDT&E of torpedoes, unmanned vehicles, 
sensors, targets, countermeasure systems, and acoustic systems.
    The NAVSEA NUWC Keyport Range Complex is divided into open ocean/
offshore areas and in shore areas:
     Open Ocean Area--air, surface, and subsurface areas of the 
NAVSEA NUWC Keyport Range Complex that lie outside of 12 nautical miles 
(nm) from land.
     Offshore Area--air, surface, and subsurface ocean areas 
within 12 nm of the Pacific Coast.
     Inshore--air, surface, and subsurface areas within the 
Puget Sound, Port Orchard Reach, Hood Canal, and Dabob Bay.

Keyport Range Site

    Located adjacent to NUWC Keyport, this range provides approximately 
1.5 square nautical miles (nm\2\) (5.1 square kilometers [km\2\]) of 
shallow underwater testing, including in-shore shallow water sites and 
a shallow lagoon to support integrated undersea warfare systems and 
vehicle maintenance and engineering activities (see Figures 1-2 and 1-3 
of the Navy's LOA application). The Navy has conducted underwater 
testing at the Keyport Range Site since 1914. Underwater tracking of 
test activities is accomplished by using temporary or portable range 
equipment. The range is currently used an average of 6 times per year 
for vehicle testing and a variety of boat and diver training 
activities, each lasting 1-30 days. There may be several activities in 
1 day. The range site also supports: (1) Detection, classification, and 
localization of test objectives and (2) magnetics measurement programs. 
Explosive warheads are not placed on test units or tested within the 
Keyport Range Site.

DBRC Site

    Currently, the DBRC Site assets include the Dabob Bay Military 
Operating Area (MOA), the Hood Canal North and South MOAs adjacent to 
Submarine Base (SUBASE) Bangor, and the Connecting Waters (see Figures 
1-2 and 1-4 of the Navy's LOA application). The DBRC Site is the Navy's 
premier location within the U.S. for RDT&E of underwater systems such 
as torpedoes, countermeasures, targets, and ship systems. Primary 
activities at the DBRC Site support proofing of underwater systems, 
research and development test support, and Fleet training and tactical 
evaluations involving aircraft, submarines, and surface ships. Tests 
and evaluations of underwater systems, from the first prototype and 
pre-production stages up through Fleet activities (inception to 
deployment), ensure reliability and availability of underwater systems 
and their Fleet components. As with the Keyport Range Site, there are 
no explosive warheads tested or placed on test units.
    The DBRC Site also supports acoustic/magnetic measurement programs. 
These programs include underwater vehicle/ship noise/magnetic signature 
recording, radiated sound investigations, and other acoustic 
evaluations. In the course of these activities, various combinations of 
aircraft, submarines, and surface ships are used as launch platforms. 
Test equipment may also be launched or deployed from shore off a pier 
or placed in the water by hand. NUWC Keyport currently conducts 
activities within four underwater testing areas in the DBRC Site. These 
areas are:
     Dabob Bay MOA--a deep-water range in Jefferson County 
approximately 14.5 nm\2\ (49.9 km\2\) in size. The acoustic tracking 
space within the range is approximately 7.3 by 1.3 nm (13.5 by 2.4 km) 
(9.5 nm\2\ [32.4 km\2\]) with a maximum depth of 600 ft (183 m). The 
Dabob Bay MOA is the principal range and the only component of the DBRC 
Site with extensive acoustic monitoring instrumentation installed on 
the seafloor, allowing for object tracking, communications, passive 
sensing, and target simulation.
     Hood Canal MOAs--There are two deep-water operating areas 
adjacent to SUBASE Bangor in Hood Canal: Hood Canal MOA South, which is 
approximately 4.5 nm\2\ (15.4 km\2\) in size, and Hood Canal MOA North, 
which is approximately 7.9 nm\2\ (27.0 km\2\) in size. Both areas have 
an average depth of 200 ft (61 m). The Hood Canal MOAs are used for 
vessel sensor accuracy tests and launch and recovery of test systems 
where tracking is optional.
     Connecting Waters--the portion of the Hood Canal that 
connects the Dabob Bay MOA with the Hood Canal MOAs. The shortest 
distance between the Dabob Bay MOA and Hood Canal MOA South by water is 
approximately 5.8 nm\2\ (19.8 km\2\). Water depth in the Connecting 
Waters is typically greater than 300 ft (91 m).

QUTR Site

    The Navy has conducted underwater testing at the QUTR Site since 
1981 and maintains a control center at the Kalaloch Ranger Station. As 
at the other range sites, no explosive warheads are used at the QUTR 
Site. The QUTR Site is a rectangular-shaped test area of about 48.3 
nm\2\ (165.5 km\2\), located approximately 6.5 nm (12 km) off the 
Pacific Coast at Kalaloch, Washington. It

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lies within the boundaries of the Olympic Coast National Marine 
Sanctuary (OCNMS).
    The QUTR Site is instrumented to track surface vessels, submarines, 
and various undersea vehicles. Bottom sensors are permanently mounted 
on the sea floor for tracking and are maintained and configured by the 
Navy. The sensors are connected to the shore via cables, which extend 
under the beach to the bluffs and end at a Navy trailer in Kalaloch 
(National Park Service [NPS] property). In addition, portable range 
equipment may be set up prior to conducting various activities on the 
range and removed after it is no longer needed. All communications are 
sent back to NUWC Keyport for monitoring.
    This range underlies a small portion (W-237A) of the larger 
airspace unit W-237. This airspace complex comprises the northern 
portion of the Pacific Northwest Ocean Surface/Subsurface Operating 
Area (OPAREA), NOAA chart number 18500 (NOAA, 2006). Activities in this 
airspace are scheduled and coordinated with Naval Air Station (NAS) 
Whidbey Island and Commander Submarine Force, U.S. Pacific Fleet 
(COMSUBPAC).
    All range areas in the NAVSEA NUWC Keyport Range Complex Extension 
include areas where marine mammals may be found. Range activities will 
be conducted in the Keyport Site, the DBRC, and the QUTR Site. The 
proposed annual usage at each site is listed in Table 1. This includes 
tracking sonar systems, side-scan, and thermal propulsion systems.

                               Table 1--Projected Annual Days of Use by Range Site
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                                                                                                    QUTR site--
                                                   Keyport range     DBRC site      QUTR site--      surf zone
                                                       site                          offshore
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Current.........................................              55             200              14               0
Proposed........................................              60             200              16              30
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Description of the Specified Activities

    Typical activities conducted in the NAVSEA NUWC Keyport Range 
Complex Extension on the three existing range sites primarily support 
undersea warfare RDT&E program requirements, but they also support 
general equipment test and military personnel training needs, including 
Fleet activities. These activities involve mid- and high-frequency 
acoustic sources with the potential to affect marine mammals that may 
be present within the NAVSEA NUWC Keyport Range Complex Extension. 
Current and proposed activities within the Keyport Range Complex 
Extension are listed below:

Range Activities: Testing That Involves Active Acoustic Devices

    A list of the primary active acoustic sources used within the 
NAVSEA NUWC Keyport Range Complex with information on the frequency 
bands is shown in Table 2. In this document, low frequency is defined 
as below 1 kiloHertz (kHz), mid frequency is defined as between 1 kHz 
and 10 kHz, and high frequency is defined as above 10 kHz.

 Table 2--Primary Acoustic Sources Commonly Used Within the NAVSEA NUWC
                          Keyport Range Complex
------------------------------------------------------------------------
                                                         Maximum source
              Source                 Frequency (kHz)     level (dB re 1
                                                           [mu]Pa-m)
------------------------------------------------------------------------
Sonar:
    General range tracking (at                 10-100                195
     Keyport Range Site)..........
    General range tracking (at                 10-100                203
     DBRC and QUTR Sites).........
    UUV tracking..................             10-100                195
    Torpedoes.....................             10-100                233
    Range targets and special                   5-100                195
     tests (at Keyport Range Site)
    Range targets and special                   5-100                238
     tests (at DBRC and QUTR
     Sites).......................
    Special sonars (e.g., UUV               100-2,500                235
     payload).....................
    Fleet aircraft--active                       2-20                225
     sonobuoys and helo-dipping
     sonars.......................
    Side-scan.....................            100-700                235
Other Acoustic Sources:
    Acoustic modems...............             10-300                210
    Target simulator..............             0.1-10                170
    Aid to navigation (range                    70-80                210
     equipment)...................
    Sub-bottom profiler...........                2-7                210
                                                35-45                220
    Engine noise (surface vessels,            0.05-10                170
     submarines, torpedoes, UUVs).
------------------------------------------------------------------------

(1) General Range Tracking
    General range tracking on the instrumented ranges and portable 
range sites have active output in relatively wide frequency bands. 
Operating frequencies are 10 to 100 kHz. At the Keyport Range Site the 
sound pressure level (SPL) of the source (source level) is a maximum of 
195 dB re 1 [mu]Pa-m. At the DBRC and QUTR sites, the source level for 
general range tracking is a maximum of 203 dB re 1 [mu]Pa-m.
(2) UUV Tracking Systems
    UUV tracking systems operate at frequencies of 10 to 100 kHz with 
maximum source levels of 195 dB re 1 [mu]Pa-m at all range sites.
(3) Torpedo Sonars
    Torpedo sonars are used for several purposes including detection, 
classification, and location and vary in frequency from 10 to 100 kHz. 
The maximum source level of a torpedo sonar is 233 dB re 1 [mu]Pa-m.

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(4) Range Targets and Special Tests
    Range targets and special test systems are within the 5 to 100 kHz 
frequency range at the Keyport Range Site with a maximum source level 
of 195 dB re 1 [mu]Pa-m. At the DBRC and QUTR sites, the maximum source 
level is 238 dB re 1 [mu]Pa-m.
(5) Special Sonars
    Special sonars can be carried as a payload on a UUV, suspended from 
a range craft, or set on or above the sea floor. These can vary widely 
from 100 kHz to a very high frequency of 2,500 kHz for very short range 
detection and classification. The maximum source level of these 
acoustic sources is 235 dB re 1 [mu]Pa-m.
(6) Sonobuoys and Helicopter Dipping Sonar
    Sonobuoys and helicopter dipping sonars are deployed from Fleet 
aircraft and operate at frequencies of 2 to 20 kHz with maximum source 
levels of 225 dB re 1 [mu]Pa-m. Dipping sonars are active or passive 
devices that are lowered on cable by helicopters or surface vessels to 
detect or maintain contact with underwater targets.
(7) Side Scan Sonar
    Side-scan sonar is used for mapping, detection, classification, and 
localization of items on the sea floor such as cabling, shipwrecks, and 
mine shapes. It is high frequency typically 100 to 700 kHz using 
multiple frequencies at one time with a very directional focus. The 
maximum source level is 235 dB re 1 [mu]Pa-m. Side-scan and multibeam 
sonar systems are towed or mounted on a test vehicle or ship.
(8) Other Acoustic Sources
    Other acoustic sources may include acoustic modems, targets, aids 
to navigation, subbottom profilers, and engine noise.
     An acoustic modem is a communication device that transmits 
an acoustically encoded signal from a source to a receiver. Acoustic 
modems emit pulses from 10 to 300 kHz at source levels less than 210 dB 
re 1 [mu]Pa-m.
     Target simulators operate at frequencies of 100 Hertz (Hz) 
(0.1 kHz) to 10 kHz at source levels of less than 170 dB re 1 [mu]Pa-m.
     Aids to navigation transmit location data from ship to 
shore and back to ship so the crew can have real-time detailed location 
information. This is typical of the range equipment used in support of 
testing. New aids to navigation can also be deployed and tested using 
70 to 80 kHz at source levels less than 210 dB re 1 [mu]Pa-m.
     Subbottom profilers are often commercial off-the-shelf 
sonars used to determine characteristics of the sea bottom and 
subbottom such as mud above bedrock or other rocky substrate. These 
operate at 2 to 7 kHz at source levels less than 210 dB re 1 [mu]Pa-m, 
and 35 to 45 kHz at less than 220 dB re 1 [mu]Pa-m.
     There are many sources of engine noise including but not 
limited to surface vessels, submarines, torpedoes, and other UUVs. The 
acoustic energy generally ranges from 50 Hz to 10 kHz at source levels 
less than 170 dB re 1 [mu]Pa-m. Targets, both mobile and stationary, 
may simulate engine noise at these same frequencies.
    Additionally, a variety of surface vessels operate active acoustic 
depth sensors (fathometers) within the range sites, including Navy, 
private, and commercial vessels. In some cases, one or more frequencies 
are projected underwater. Bottom type, depth contours, and objects 
(e.g., cables, sunken ships) can be located using this equipment. The 
depth sensors used by NUWC Keyport are the same fathometers used by 
commercial and recreational vessels for navigational safety. Because 
these instruments are widely used and are not found to adversely impact 
the human or natural environment, they are not analyzed further.

Range Activities: Testing That Involves Non-Acoustic Activities

(1) Magnetic
    There are two types: (a) Magnetic sensors, and (b) magnetic 
sources. Magnetic sensors are passive and do not have a magnetic field 
associated with them. The sensors are bottom mounted, over the side 
(stationary or towed) or can be integrated into a UUV. They are used to 
sense the magnetic field of an object such as a surface vessel, a 
submarine, or a buried target. Magnetic sources are used to represent 
magnetic targets or are energized items such as power cables for energy 
generators (e.g. tidal). Magnetic sources generate electromagnetic 
fields (EMF). Evaluation of EMF (Navy 2008a) has shown that sources 
(e.g. Organic Airborne and Surface Influence Sweep (OASIS)) used are 
typically below 23 gauss (G) and are considered relatively minute 
strength.
(2) Oceanographic Sensor
    These sensors have been used historically to determine marine 
characteristics such as conductivity, temperature, and pressure of 
water to determine sound velocity in water. This provides information 
about how sound will travel through the water. These sensors can be 
deployed over the side from a surface craft, suspended in water, or 
carried on a UUV.
(3) Laser Imaging Detection and Ranging (LIDAR)
    Also known as light detection and ranging, LIDAR is used to measure 
distance, speed, rotation, and chemical composition and concentration 
of remote solid objects such as a ship or submerged object. LIDAR uses 
the same principle as radar. The LIDAR instrument transmits short 
pulses of laser light towards the target. The transmitted light 
interacts with and is changed by the target. Some of this light is 
reflected back to the instrument where it is analyzed. The change in 
the properties of the light enables some property of the target to be 
determined. The time it takes the light to travel to the target and 
back to the LIDAR can be used to determine the distance to the target. 
Since light attenuates rapidly in water, underwater LIDAR uses light in 
the blue-green part of the spectrum as it attenuates the least. Common 
civilian uses of LIDAR in the ocean include seabed mapping and fish 
detection. All safety issues associated with the use of lasers are 
evaluated for all applicable test activities within the range sites 
according to Navy and Federal regulations. This bounds the intensity of 
LIDAR used pursuant to this request to those systems that meet human 
safety standards.
(4) Inert Mine Hunting and Inert Mine Clearing Exercises
    Associated with testing, a series of inert mine shapes are set out 
in a uniform or random pattern to test the detection, classification 
and localization capability of the system under test. They are made 
from plastic, metal, and concrete and vary in shape. An inert mine 
shape can measure about 10 by 1.75 ft (3 by 0.5 m) and weigh about 800 
lbs (362 kg). Inert mine shapes either sit on the bottom or are 
tethered by an anchor to the bottom at various depths. Inert mine 
shapes can be placed approximately 200-300 yards (183-274 m) apart 
using a support craft and remain on the bottom until they need to be 
removed. All major components of all inert mine systems used as 
`targets' for inert mine hunting systems are removed within 2 years.
    NMFS does not believe that those Range activities that involve non-
acoustic testing will have adverse impacts to marine mammals, 
therefore,

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they are not analyzed further and will not be covered under the 
proposed rule.

Increased Activities Due to Range Extension

    The proposed range extension would expand the geographic area for 
all three range sites and increase the tempo of activities in the 
Keyport and QUTR ranges sites. A detailed list of the proposed annual 
range is provided in Table 3.
(1) Keyport Range Site
    Range boundaries of the Keyport Range Site would be extended to the 
north, east and south, increasing the size of the range from 1.5 nm\2\ 
to 3.2 nm\2\ (5.1 km\2\ to 11.0 km\2\). The average annual days of use 
of the Keyport Range Site would increase from the current 55 days to 60 
days.
(2) DBRC Site
    The southern boundary of DBRC Site would be extended to the Hamma 
Hamma River and its northern boundary would be extended to 1 nm (2 km) 
south of the Hood Canal Bridge (Highway 104). This extension would 
increase the size of the current operating area from approximately 32.7 
nm\2\ (112.1 km\2\) to approximately 45.7 nm\2\ (150.8 km\2\) and would 
afford a straight run of approximately 27.5 nm (50.9 km). There would 
be no change in the number and types of activities from the existing 
range activities at DBRC Site, and no increase in average annual days 
of use due to the range extension at this site.
(3) QUTR Site
    Range boundaries of QUTR Site would be extended to coincide with 
the overlying special use airspace of W-237A plus a 7.8 nm\2\ (26.6 
km\2\) surf zone at Pacific Beach. The total range area would increase 
from approximately 48.3 nm\2\ (165.5 km\2\) to approximately 1,839.8 
nm\2\ (6,310.2 km\2\). The average annual number of days of use for 
offshore activities would increase from 14 days/year to 16 days/year in 
the offshore area. The average annual days of use for surf-zone 
activities would increase from 0 days/year to 30 days/year.
[GRAPHIC] [TIFF OMITTED] TP07JY09.002

Description of Marine Mammals in the Area of the Specified Activities

    The information on marine mammals and their distribution and 
density are based on the data gathered from NMFS, United States Fish 
and Wildlife Service (USFWS) and recent references, literature searches 
of search engines, peer review journals, and other technical reports, 
to provide a regional context for each species. The data were compiled 
from available sighting records, literature, satellite tracking, and 
stranding and by-catch data.
    A total of 24 cetacean species and subspecies and 5 pinniped 
species are known to occur in Washington State waters; however, several 
are seen only rarely. Seven of these marine mammal species are listed 
as Federally-endangered under the Endangered Species Act (ESA) occur or 
have the potential to occur in the proposed action area: blue whale 
(Balaenoptera musculus), fin whale (B. physalus), Sei whale (B. 
borealis), humpback whale (Megaptera novaengliae), north Pacific right 
whale (Eubalaena japonica), sperm whale (Physeter macrocephalus), and 
the southern resident population of

[[Page 32269]]

killer whales (Orcinus orca). The species, Steller sea lion (Eumetopias 
jubatus), is listed as threatened under the ESA.
    Survey data concerning the inland waters of Puget Sound are sparse. 
There have been few comprehensive studies of marine mammals in inland 
waters, and those that have occurred have focused on inland waters 
farther north (Strait of Juan de Fuca, San Juan/Gulf Islands, Strait of 
Georgia) (Osmek et al., 1998). Most published information focuses on 
single species (e.g., harbor seals, Jeffries et al., 2003) or are stock 
assessment reports published by NMFS (e.g., Carretta et al., 2008).
    Survey data for the offshore waters of Washington State, including 
the area of the QUTR Site, are somewhat better, particularly for 
cetaceans. The NMFS conducted vessel surveys in the region in 1996 and 
2001, which are summarized in Barlow (2003) and Appler et al. (2004). 
Vessel surveys were again conducted by NMFS in summer 2005, and 
included finer-scale survey lines within the OCNMS (Forney, 2007). 
Cetacean densities from this most recent effort were used wherever 
possible; older density values (2001 or 1996) were used when more 
recent values were not available. Some cetacean densities (gray and 
killer whale, harbor porpoise) were obtained from sources other than 
the broad scale surveys indicated above and the methodologies of 
deriving the densities are included in the Navy's LOA application.
    Pinniped at-sea density is not often available because pinniped 
abundance is most often obtained via shore counts of animals at known 
rookeries and haulouts. Therefore, densities of pinnipeds were derived 
differently from those of cetaceans. Several parameters were identified 
from the literature, including area of stock occurrence, number of 
animals (which may vary seasonally) and season, and those parameters 
were then used to calculate density. Determining density in this manner 
is risky as the parameters used usually contain error (e.g., geographic 
range is not exactly known and needs to be estimated, abundance 
estimates usually have large variances) and, as is true of all density 
estimates, they assume that animals are always distributed evenly 
within an area, which is likely rarely true. However, this remains one 
of the few means available to determine at-sea density for pinnipeds.
    Sea otters occur along the northern Washington coast. Density of 
sea otters was published as animals/km, which was modified to provide 
density per area. Since sea otters are under the U.S. Fish and Wildlife 
Service jurisdiction, they are not considered in this document.
    The following are brief descriptions of the temporal and spatial 
distribution and abundance of marine mammals throughout the NAVSEA NUWC 
Keyport Range Complex Extension.

Keyport Range Site

    A total of five cetaceans and three pinnipeds are known to occur 
within central Puget Sound, which encompasses the Keyport action area, 
but several of these species have never been observed in Port Orchard 
Narrows or in the action area (Table 4). Humpback whales, minke whales, 
killer whales, and Steller sea lions are expected to be uncommon to 
rare in southern Puget Sound and have never been seen in the Keyport 
action area. Density estimates for these species are available for 
Puget Sound as a whole, but since these species have never been 
recorded or observed in the action area, the densities for the action 
area are shown as ``0'' to reflect this. The proposed extension area of 
the Keyport Range Site is listed as critical habitat for Southern 
Resident killer whales. The current Keyport Range Site is outside the 
critical habitat area.

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DBRC Site

    Six cetaceans and three pinnipeds are known to occur or potentially 
occur within the DBRC action area (Table 5). Density estimates for 
these species are available for Puget Sound as a whole, but since these 
species have never been recorded or observed in the action area, the 
densities for the action area are shown as ``0'' to reflect this. There 
is no designated or proposed critical habitat for marine mammals within 
the DBRC action area.

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[GRAPHIC] [TIFF OMITTED] TP07JY09.004

3.2.3 QUTR Site

    The diversity of marine mammals that occur in QUTR is greater than 
that in the Puget Sound ranges and is listed in Table 6.
BILLING CODE 3510-22-P

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[GRAPHIC] [TIFF OMITTED] TP07JY09.006

    More detailed description of marine mammal density estimates within 
the NAVSEA NUWC Keyport Range Complex Extension is provided in the 
Navy's LOA application.

A Brief Background on Sound

    An understanding of the basic properties of underwater sound is 
necessary to comprehend many of the concepts and analyses presented in 
this document. A summary is included below.
    Sound is a wave of pressure variations propagating through a medium 
(for the sonar considered in this proposed rule, the medium is marine 
water). Pressure variations are created by compressing and relaxing the 
medium. Sound measurements can be expressed in two forms: intensity and 
pressure. Acoustic intensity is the average rate of energy transmitted 
through a unit area in a specified direction and is expressed in watts 
per square meter (W/m\2\). Acoustic intensity is rarely measured 
directly, it is derived from ratios of pressures; the standard 
reference pressure for underwater sound is 1 microPascal (microPa); for 
airborne sound, the standard reference pressure is 20 microPa (Urick, 
1983).
    Acousticians have adopted a logarithmic scale for sound 
intensities, which is denoted in decibels (dB). Decibel measurements 
represent the ratio between a measured pressure value and a reference 
pressure value (in this case 1 microPa or, for airborne sound, 20 
microPa). The logarithmic nature of the scale means that each 10 dB 
increase is a tenfold increase in power (e.g., 20 dB is a 100-fold 
increase, 30 dB is a 1,000-fold increase). Humans perceive a 10-dB 
increase in noise as a doubling of sound level, or a 10 dB decrease in 
noise as a halving of sound level. The term ``sound pressure level'' 
implies a decibel measure and a reference pressure that is used as the 
denominator of the ratio. Throughout this document, NMFS uses 1 microPa 
as a standard reference pressure unless noted otherwise.
    It is important to note that decibels underwater and decibels in 
air are not the same and cannot be directly compared. To estimate a 
comparison between sound in air and underwater, because of the 
different densities of air and water and the different decibel 
standards (i.e., reference pressures) in water and air, a sound with 
the same intensity (i.e., power) in air and in water would be 
approximately 61.5 dB lower in air. Thus, a sound that is 160 dB loud 
underwater would have the same approximate effective intensity as a 
sound that is 98.5 dB loud in air.
    Sound frequency is measured in cycles per second, or Hertz 
(abbreviated Hz), and is analogous to musical pitch; high-pitched 
sounds contain high frequencies and low-pitched sounds contain low 
frequencies. Natural sounds in the ocean span a huge range of 
frequencies: from earthquake noise at 5 Hz to harbor porpoise clicks at 
150,000 Hz (150 kHz). These sounds are so low or so high in pitch that 
humans cannot even hear them; acousticians call these infrasonic and 
ultrasonic sounds, respectively. A single sound may be made up of many 
different frequencies together. Sounds made up of only a small range of 
frequencies are called ``narrowband'', and sounds with a broad range of 
frequencies are called ``broadband''; airguns are an example of a 
broadband sound source and tactical sonars are an example of a 
narrowband sound source.
    When considering the influence of various kinds of sound on the 
marine environment, it is necessary to understand that different kinds 
of marine life are sensitive to different frequencies of sound. Based 
on available behavioral data, audiograms derived using auditory evoked 
potential, anatomical modeling, and other data, Southall et al. (2007) 
designated ``functional hearing groups'' and estimated the lower and 
upper frequencies of functional hearing of the groups. Further, the 
frequency range in which each group's hearing is estimated as being 
most sensitive is represented in the flat part of the M-weighting 
functions developed for each group. The functional groups and the 
associated frequencies are indicated below:
     Low frequency cetaceans (13 species of mysticetes): 
Functional hearing is estimated to occur between approximately 7 Hz and 
22 kHz.
     Mid-frequency cetaceans (32 species of dolphins, six 
species of larger toothed whales, and 19 species of beaked and 
bottlenose whales): Functional hearing is estimated to occur between 
approximately 150 Hz and 160 kHz.
     High frequency cetaceans (eight species of true porpoises, 
six species of river dolphins, Kogia, the franciscana, and four species 
of cephalorhynchids): Functional hearing is estimated to occur between 
approximately 200 Hz and 180 kHz.
     Pinnipeds in Water: Functional hearing is estimated to 
occur between approximately 75 Hz and 75 kHz, with the greatest 
sensitivity between approximately 700 Hz and 20 kHz.
     Pinnipeds in Air: Functional hearing is estimated to occur 
between approximately 75 Hz and 30 kHz.
    Because ears adapted to function underwater are physiologically 
different from human ears, comparisons using decibel measurements in 
air would still not be adequate to describe the effects of a sound on a 
cetacean. When sound travels away from its source, its loudness 
decreases as the distance from the source increases (propagation). 
Thus, the loudness of a sound at its source is higher than the loudness 
of that same sound a kilometer distant. Acousticians often refer to the 
loudness of a sound at its source (typically measured one meter from 
the source) as the source level and the loudness of sound elsewhere as 
the received level. For example, a humpback whale three kilometers from 
an airgun that has a source level of 230 dB may only be

[[Page 32274]]

exposed to sound that is 160 dB loud, depending on how the sound 
propagates. As a result, it is important not to confuse source levels 
and received levels when discussing the loudness of sound in the ocean.
    As sound travels from a source, its propagation in water is 
influenced by various physical characteristics, including water 
temperature, depth, salinity, and surface and bottom properties that 
cause refraction, reflection, absorption, and scattering of sound 
waves. Oceans are not homogeneous and the contribution of each of these 
individual factors is extremely complex and interrelated. The physical 
characteristics that determine the sound's speed through the water will 
change with depth, season, geographic location, and with time of day 
(as a result, in actual sonar operations, crews will measure oceanic 
conditions, such as sea water temperature and depth, to calibrate 
models that determine the path the sonar signal will take as it travels 
through the ocean and how strong the sound signal will be at a given 
range along a particular transmission path). As sound travels through 
the ocean, the intensity associated with the wavefront diminishes, or 
attenuates. This decrease in intensity is referred to as propagation 
loss, also commonly called transmission loss.

Metrics Used in This Document

    This section includes a brief explanation of the two sound 
measurements (sound pressure level (SPL) and sound exposure level 
(SEL)) frequently used in the discussions of acoustic effects in this 
document.
SPL
    Sound pressure is the sound force per unit area, and is usually 
measured in microPa, where 1 Pa is the pressure resulting from a force 
of one newton exerted over an area of one square meter. SPL is 
expressed as the ratio of a measured sound pressure and a reference 
level. The commonly used reference pressure level in underwater 
acoustics is 1 microPa, and the units for SPLs are dB re: 1 microPa.

    SPL (in dB) = 20 log (pressure/reference pressure)

    SPL is an instantaneous measurement and can be expressed as the 
peak, the peak-peak, or the root mean square (rms). Root mean square, 
which is the square root of the arithmetic average of the squared 
instantaneous pressure values, is typically used in discussions of the 
effects of sounds on vertebrates. All references to SPL in this 
document refer to the root mean square. SPL does not take the duration 
of a sound into account. SPL is the applicable metric used in the risk 
continuum, which is used to estimate behavioral harassment takes (see 
Level B Harassment Risk Function (Behavioral Harassment) Section).
SEL
    SEL is an energy metric that integrates the squared instantaneous 
sound pressure over a stated time interval. The units for SEL are dB 
re: 1 microPa\2\-s.

SEL = SPL + 10log (duration in seconds)

    As applied to tactical sonar, the SEL includes both the SPL of a 
sonar ping and the total duration. Longer duration pings and/or pings 
with higher SPLs will have a higher SEL. Surface-ship hull-mounted 
sonars, known as tactical sonars, are not used by NAVSEA NUWC Keyport. 
If an animal is exposed to multiple pings, the SEL in each individual 
ping is summed to calculate the total SEL. The total SEL depends on the 
SPL, duration, and number of pings received. The thresholds that NMFS 
uses to indicate the received levels at which the onset of temporary 
threshold shift (TTS) and permanent threshold shift (PTS) in hearing 
are likely to occur are expressed in SEL.

Potential Impacts to Marine Mammal Species

    The following sections discuss the potential effects from noise 
related to active acoustic devices that would be used in the proposed 
Keyport Range Complex Extension.
    For activities involving active acoustic sources such as tactical 
sonar, NMFS's analysis identifies the probability of lethal responses, 
physical trauma, sensory impairment (permanent and temporary threshold 
shifts and acoustic masking), physiological responses (particular 
stress responses), behavioral disturbance (that rises to the level of 
harassment), and social responses that would be classified as 
behavioral harassment or injury and/or would be likely to adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival. It should be noted that the description below 
is based on more powerful mid-frequency active sonar (MFAS) used on 
surface ships. The NAVSEA NUWC Keyport Range does not utilize these 
sources in RDT&E activities. Many of these severe effects (e.g., 
mortality, acoustically mediated bubble growth, and stranding) are not 
likely to occur for acoustic sources used in the proposed Keyport Range 
activities, as shown in Estimated Takes of Marine Mammals section.

Direct Physiological Effects

    Based on the literature, there are two basic ways that MFAS 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 might 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 recognize them) following exposure to a 
sufficiently intense sound, it is referred to as a noise-induced 
threshold shift (TS). An animal can experience temporary threshold 
shift (TTS) or permanent threshold shift (PTS). TTS can last from 
minutes or hours to days (i.e., there is recovery), occurs 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 by only 6 dB or reduced by 30 dB). PTS is permanent 
(i.e., there is no recovery), but as with TTS occurs in a specific 
frequency range and amount.
    The following physiological mechanisms are thought to play a role 
in inducing auditory TSs: 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 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. For continuous sounds, exposures of 
equal energy (the same SEL) will lead to approximately equal effects. 
For intermittent sounds, less TS will occur than from a continuous 
exposure with the same energy (some recovery will occur between 
exposures) (Kryter et al., 1966; Ward, 1997). For example, one short 
but loud (higher SPL) sound exposure may induce the same impairment as 
one

[[Page 32275]]

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, very prolonged 
exposure to sound strong enough to elicit TTS, or shorter-term exposure 
to sound levels well above the TTS threshold, can cause PTS, at least 
in terrestrial mammals (Kryter, 1985) (although in the case of MFAS, 
animals are not expected to be exposed to levels high 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 
cetaceans, published data are limited to a captive bottlenose dolphin 
and beluga whale (Finneran et al., 2000, 2002b, 2005a; Schlundt et al., 
2000; Nachtigall et al., 2003, 2004).
    Marine mammal hearing plays a critical role in communication with 
conspecific, and interpreting environmental cues for purposes such as 
predator avoidance and prey capture. Depending on the frequency range 
of TTS degree (dB), duration, and frequency range of TTS, and the 
context in which it is experienced, TTS can have effects on marine 
mammals ranging from discountable to serious (similar to those 
discussed in auditory masking, below). For example, a marine mammal may 
be able to readily compensate for a brief, relatively small amount of 
TTS in a non-critical frequency range that takes place during a time 
when the animal is traveling through the open ocean, 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 long term condition. Of note, reduced hearing sensitivity as a 
simple function of development and aging has been observed in marine 
mammals, as well as humans and other taxa (Southall et al., 2007), so 
we can infer that strategies exist for coping with this condition to 
some degree, though likely not without cost. There is no empirical 
evidence that exposure to MFAS can cause PTS in any marine mammals; 
instead the probability of PTS has been inferred from studies of TTS 
(see Richardson et al., 1995).

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 would be long 
enough to drive bubble growth to any substantial size, if such a 
phenomenon occurs. Recent work conducted by Crum et al. (2005) 
demonstrated the possibility of rectified diffusion for short duration 
signals, but at sound exposure levels and tissue saturation levels that 
are improbable to occur in a diving marine mammal. 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. 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). In this scenario, the rate of ascent would 
need to be sufficiently rapid to compromise behavioral or physiological 
protections against nitrogen bubble formation. 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) concluded that in vivo bubble formation, 
which may be exacerbated by 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 MFAS can 
lead to strandings is included in the Behaviorally Mediated Bubble 
Growth section, after the summary of strandings.

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

[[Page 32276]]

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. (1995) 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 odontocetes (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).
    As mentioned previously, the functional hearing ranges of marine 
mammals all encompass the frequencies of the active acoustic sources 
used in the Navy's Keyport Range activities. Additionally, almost all 
species' vocal repertoires span across the frequencies of the 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. 
However, because the pulse length and duty cycle of source signals are 
of short duration and would not be continuous, masking is unlikely to 
occur as a result of exposure to active acoustic sources during the 
RDT&E activities in the Keyport Range Complex Extension Study Area.

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 are more important than 
detecting a vocalization (Brenowitz, 1982; Brumm et al., 2004; Dooling, 
2004; Marten and Marler, 1977; Patricelli et al., 2006). Most animals 
that vocalize have evolved an ability to make adjustments to their 
vocalizations to increase the signal-to-noise ratio, active space, and 
recognizability of their vocalizations in the face of temporary changes 
in background noise (Brumm et al., 2004; Patricelli et al., 2006). 
Vocalizing animals will make one or more of the following adjustments 
to their vocalizations: Adjust the frequency structure; adjust the 
amplitude; adjust temporal structure; or adjust 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 
response.
    In the case of many stressors, an animal's first and 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 
autonomic nervous system and the classical ``fight or flight'' response 
which includes the cardiovascular system, the gastrointestinal system, 
the exocrine glands, and the adrenal medulla to produce changes in 
heart rate, blood pressure, and gastrointestinal activity that humans 
commonly associate with ``stress.'' These responses have a relatively 
short duration and may or may not have significant long-term effects on 
an animal's welfare.
    An animal's third line of defense to stressors involves its 
neuroendocrine or sympathetic nervous systems; the system that has 
received the most study has been the hypothalmus-pituitary-adrenal 
system (also known as the HPA axis in mammals or the hypothalamus-
pituitary-interrenal axis in fish and some reptiles). Unlike stress 
responses associated with the autonomic nervous system, virtually all 
neuro-endocrine functions that are affected by stress--including immune 
competence, reproduction, metabolism, and behavior--are regulated by 
pituitary hormones. Stress-induced changes in the secretion of 
pituitary hormones have been implicated in failed reproduction (Moberg, 
1987; Rivier, 1995) and altered metabolism (Elasser et al., 2000), 
reduced immune competence (Blecha, 2000) and behavioral disturbance. 
Increases in the circulation of glucocorticosteroids (cortisol,

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corticosterone, and aldosterone in marine mammals; 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 
respon