Taking of Marine Mammals Incidental to Specified Activities; U.S. Marine Corps Training Exercises at Air Station Cherry Point, 32398-32416 [2010-13748]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 75, Number 109 (Tuesday, June 8, 2010)]
[Notices]
[Pages 32398-32416]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-13748]



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DEPARTMENT OF COMMERCE



National Oceanic and Atmospheric Administration



RIN 0648-XT25




Taking of Marine Mammals Incidental to Specified Activities; U.S. 

Marine Corps Training Exercises at Air Station Cherry Point



AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 

Atmospheric Administration (NOAA), Commerce.



ACTION: Notice; proposed incidental harassment authorization; request 

for comments.



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SUMMARY: NMFS has received an application from the U.S. Marine Corps 

(USMC) requesting authorization to take marine mammals incidental to 

various training exercises at Marine Corps Air Station (MCAS) Cherry 

Point Range Complex, North Carolina. The USMC's activities are 

considered military readiness activities pursuant to the Marine Mammal 

Protection Act (MMPA), as amended by the National Defense Authorization 

Act (NDAA) for Fiscal Year 2004. Pursuant to the MMPA, NMFS is 

requesting comments on its proposal to issue an incidental harassment 

authorization (IHA) to the USMC to take bottlenose dolphins (Tursiops 

truncatus), by Level B harassment only, from specified activities.



DATES: Comments and information must be received no later than July 8, 

2010.



ADDRESSES: Comments on the application 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. The mailbox address for 

providing e-mail comments is PR1.0648-XT25@noaa.gov. NMFS is not 

responsible for e-mail comments sent to addresses other than the one 

provided here. Comments sent via e-mail, including all attachments, 

must not exceed a 10-megabyte file size.



[[Page 32399]]



    Instructions: All comments received are a part of the public record 

and may be posted to https://www.nmfs.noaa.gov/pr/permits/incidental.htm 

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.

    A copy of the application containing a list of the references used 

in this document may be obtained by writing to the address specified 

above, telephoning the contact listed below (see FOR FURTHER 

INFORMATION CONTACT), or visiting the Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm. The following associated 

document is also available at the same Internet address: Environmental 

Assessment MCAS Cherry Point Range Operations (USMC 2009). Documents 

cited in this notice may also be viewed, by appointment, during regular 

business hours, at the aforementioned address.



FOR FURTHER INFORMATION CONTACT: Jaclyn Daly, Office of Protected 

Resources, NMFS, (301) 713-2289.



SUPPLEMENTARY INFORMATION:



Background



    Sections 101(a)(5)(A) 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 marine mammals by U.S. citizens who engage 

in a specified activity (other than commercial fishing) 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 for incidental takings may 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 certain 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.''

    Section 101(a)(5)(D) of the MMPA established an expedited process 

by which citizens of the United States can apply for an authorization 

to incidentally take small numbers of marine mammals by harassment. 

Section 101(a)(5)(D) establishes a 45-day time limit for NMFS review of 

an application followed by a 30-day public notice and comment period on 

any proposed authorizations for the incidental harassment of marine 

mammals. Within 45 days of the close of the comment period, NMFS must 

either issue or deny the authorization.

    The NDAA (Pub. L. 108-136) removed the ``small numbers'' and 

``specified geographical region'' limitations 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 August 6, 2009, NMFS received an application from the USMC 

requesting an IHA for the harassment of Atlantic bottlenose dolphins 

(Tursiops truncatus) incidental to air-to-surface and surface-to-

surface training exercises conducted around two bombing targets (BTs) 

within southern Pamlico Sound, North Carolina, at MCAS Cherry Point. 

NMFS requested additional information regarding the specified 

activities and received responses from the USMC on October 29, 2009, 

completing the application.

    Weapon delivery training would occur at two BTs: Brant Island 

Target (BT-9) and Piney Island Bombing Range (BT-11). Training at BT-9 

would involve air-to-surface (from aircraft to in-water targets) and 

surface-to-surface (from vessels to in-water targets) warfare training, 

including bombing, strafing, special (laser systems) weapons; surface 

fires using non-explosive and explosive ordnance; and mine laying 

exercises (inert). Training at BT-11 would involve air-to-surface 

exercises to provide training in the delivery of conventional (non-

explosive) and special (laser systems) weapons. Surface-to-surface 

training by small military watercraft would also be executed here. The 

types of ordnances proposed for use at BT-9 and BT-11 include small 

arms, large arms, bombs, rockets, missiles, and pyrotechnics. All 

munitions used at BT-11 are inert, practice rounds. No live firing 

occurs at BT-11. Training for any activity may occur year-round. Active 

sonar is not a component of these specified training exercises; 

therefore, discussion of marine mammal harassment from active sonar 

operations is not included within this notice.



Description of the Specified Activity



    The USMC is requesting authorization to harass bottlenose dolphins 

from ammunition firing conducted at two BTs within MCAS Cherry Point. 

The BTs are located at the convergence of the Neuse River and Pamlico 

Sound, North Carolina. BT-9 is a water-based target located 

approximately 52 km (28 nautical miles [nm]) northeast of MCAS Cherry 

Point. The BT-9 target area ranges in depth from 1.2 m to 6.1 m, with 

the shallow areas concentrated along the Brandt Island Shoal (which 

runs down the middle of the restricted area in a northwest to southeast 

orientation). The target itself consists of three ship hulls grounded 

on Brant Island Shoals, located approximately 4.8 km (3 miles [mi]) 

southeast of Goose Creek Island. Inert (non-explosive) ordnance up to 

454 kilograms (kg) (1,000 lbs) and live (explosive) ordnance up to 45.4 

kg (100 lbs) TNT equivalent, including ordnance released during 

strafing, are authorized for use at this target range. The target is 

defined by a 6 statute-mile (SM) diameter prohibited area designated by 

the U.S. Army Corps of Engineers, Wilmington District (33 CFR 334.420). 

Non-military vessels are not permitted within the prohibited area, 

which is delineated by large signs located on pilings surrounding the 

perimeter of the BT. BT-9 also provides a mining exercise area; 

however, all mine exercises are simulation only and do not involve 

detonations. BT-9 standard operating procedures limit live ordnance 

deliveries to a maximum explosive weight of 100 lbs TNT equivalent. 

Based on 2007 data, the USMC would conduct approximately 1,539 

aircraft-based and 165 vessel-based sorties, annually, at BT-9. The 

standard sortie consists of two aircraft per bombing run or an average 

of two and maximum of six vessels.

    BT-11 is a 50.6 square kilometers (sq km) (19.5 square miles [sq 

mi]) complex of land- and water-based targets on Piney Island. The BT-

11 target area ranges in depth from 0.3 m along the shoreline to 3.1 m 

in the center of Rattan Bay (BA 2001). The in-water stationary targets 

of BT-11 consist of a barge and patrol (PT) boat located in roughly the 

center of Rattan Bay. The barge target is approximately 135 ft by 40 ft 

in dimension. The PT boat is approximately 110 ft by 35 ft in



[[Page 32400]]



dimension. Water depths in the center of Rattan Bay are estimated as 

2.4 to 3 m (8 to 10 ft) with bottom depths ranging from 0.3 to 1.5 m (1 

to 5 ft) adjacent to the shoreline of Piney Island. A shallow ledge, 

with substrate expected to be hard-packed to hard bottom, surrounds 

Piney Island. No live firing occurs at BT-11; all munitions used are 

inert, non-explosive practice rounds. Only 36 percent of all munitions 

fired at BT-11 occur over water; the remaining munitions are fired to 

land based targets on Piney Island. Based on 2007 data, the USMC would 

conduct approximately 6,727 aircraft-based and 51 vessel-based sorties, 

annually, at BT-11.

    All inert and live-fire exercises at MCAS Cherry Point ranges are 

conducted so that all ammunition and other ordnances strike and/or fall 

on the land or water based target or within the existing danger zones 

or water restricted areas. A danger zone is a defined water area that 

is closed to the public on an intermittent or full-time basis for use 

by military forces for hazardous operations such as target practice and 

ordnance firing. A water restricted area is a defined water area where 

public access is prohibited or limited in order to provide security for 

Government property and/or to protect the public from the risks of 

injury or damage that could occur from the government's use of that 

area (33 CFR 334.2). Surface danger zones are designated areas of 

rocket firing, target practice, or other hazardous operations (33 CFR 

334.420). The surface danger zone (prohibited area) for BT-9 is a 4.8 

km radius centered on the south side of Brant Island Shoal. The surface 

danger zone for BT-11 is a 2.9 km radius centered on a barge target in 

Rattan Bay.

    According to the application, the USMC is requesting take of marine 

mammals incidental to specified activities at MCAS Cherry Point Range 

Complex, located within Pamlico Sound, North Carolina. These activities 

include gunnery; mine laying; bombing; or rocket exercises and are 

classified into two categories here based on delivery method: (1) 

Surface-to-surface gunnery and (2) air-to-surface bombing. Exercises 

may occur year round, day or night (approximately 15 percent of 

training occurs at night).



Surface-to-Surface Gunnery Exercises



    Surface-to-surface fires are fires from boats at sea to targets at 

sea. These can be direct (targets are within sight) or indirect 

(targets are not within sight). Gunnery exercise employing only direct 

fire is the only category of surface-to-surface activity currently 

conducted within the MCAS Cherry Point BTs. An average of two and 

maximum of six small boats (24-85 ft), or fleet of boats, typically 

operated by Special Boat Team personnel, use a machine gun to attack 

and disable or destroy a surface target that simulates another ship, 

boat, swimmer, floating mine or near shore land targets. Vessels travel 

between 0-20 kts with an average of two vessels actually conducting 

surface-to-surface firing activities. Typical munitions are 7.62 

millimeter (mm) or .50 caliber (cal) machine guns; and/or 40 mm Grenade 

machine guns. This exercise is usually a live-fire exercise, but at 

times blanks may be used so that the boat crews can practice their ship 

handling skills. The goal of training is to hit the targets; however, 

some munitions may bounce off the targets and land in the water or miss 

the target entirely. Additionally, G911 Concussion hand grenades (inert 

and live) are used; however, these are not aimed at targets, as the 

goal is to learn how to throw them into the water.

    The estimated amount of munitions expended at BT-9 and BT-11 during 

this training can be found in Table 1 below. In 2007, a total of 216 

boat sorties were conducted at BT-9 and BT-11 year round with equal 

distribution of training effort throughout the seasons. Live fires 

constitute approximately 90 percent of all surface-to-surface gunnery 

events. The majority of sorties originated and practiced at BT-9 as no 

live fire is conducted at BT-11. The USMC has indicated a comparable 

number of sorties would occur throughout the IHA timeframe. There is no 

specific schedule associated with the use of ranges by the small boat 

teams. However, exercises tend to be scheduled for 5-day blocks with 

exercises at various times throughout that timeframe. There is no 

specific time of year or month training occurs as variables such as 

deployment status, range availability, and completion of crew specific 

training requirements influence schedules.

    A number of different types of boats are used during surface-to-

surface exercises depending on the unit using the boat and their 

mission and include versions of Small Unit River Craft, Combat Rubber 

Raiding Craft, Rigid Hull Inflatable Boats, Patrol Craft. They are 

inboard or outboard, diesel or gasoline engines with either propeller 

or water jet propulsion. Boat crews approach, at a maximum of 20 kts, 

and engage targets simulating other boats, swimmers, floating mines, or 

near shore land targets with 7.62 mm or .50 cal machine guns; 40 mm 

grenade machine guns; or M3A2 Concussion hand grenades (approximately 

200, 800, 10, and 10 rounds respectively). Vessels typically travel in 

linear paths and do not operate erratically. Other vessels may be 

located within the BTs; however, these are support craft and do not 

participate in munitions expenditures. The purpose of the support craft 

is to remotely control High Speed Maneuvering Surface Targets (HSMSTs) 

or to conduct maintenance on electronic equipment located in the towers 

at BT-9. Support craft are typically anchored or tied to marker pilings 

during HSMST operations or tied to equipment towers. When underway, 

vessels do not typically travel faster than 12-18 kts or in an erratic 

manner.



      Table 1--Type and Amount of Munitions Expended at BT-9 and BT-11 During Surface-to-Surface Exercises

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

                                                 Annual No.                                           Munitions

                     Range                       of sorties              Munitions type                expended

                                                    \1\                                                annually

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

BT-9..........................................          165  5.56 mm...............................        1,468

                                                ...........  7.62 mm...............................      218,500

                                                ...........  .50 cal...............................      166,900

                                                ...........  40 mm Grenade--Inert..................       15,734

                                                ...........  40 mm Grenade--Live (HE)..............        9,472

                                                ...........  G911 Grenade..........................          144

BT-11.........................................           51  7.62 mm...............................       44,100

                                                ...........  .40 cal...............................        4,600

                                                ...........  40 mm Grenade--Inert..................        1,517



[[Page 32401]]



 

                                                ...........  40 mm Illumination--Inert.............            9

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

\1\ Sorties are from FY 2007 CURRS data.



Air-to-Surface



    Air-to-surface training involves ordnance delivered from aircraft 

and aimed at targets on the water's surface or on land in the case of 

BT-11. A description of the types of targets used at MCAS Cherry Point 

is provided in the section on BTs above. There are four types of air-

to-surface activities conducted within the MCAS Cherry Point BTs: Mine 

laying; bombing; gunnery or rocket exercises which are carried out via 

fixed wing or rotary wing aircraft.

Mine Laying Exercises

    Mine Warfare (MIW) includes the strategic, operational, and 

tactical use of mines and mine countermine measures. MIW is divided 

into two basic subdivisions: (a) The laying of mines to degrade the 

enemy's capabilities to wage land, air, and maritime warfare, and (b) 

the countering of enemy-laid mines to permit friendly maneuver or use 

of selected land or sea areas (DoN, 2007). MCAS Cherry Point would only 

engage in mine laying exercises as described below. No detonations of 

any mine device are involved with this training.

    During mine laying, a fixed-wing or maritime patrol aircraft (P-3 

or P-8) typically drops a series of about four inert mine shapes in an 

offensive or defensive pattern, making multiple passes along a pre-

determined flight azimuth, and dropping one or more shapes each time. 

Mine simulation shapes include MK76, MK80 series, and BDU practice 

bombs ranging from 25 to 2,000 pounds in weight. There is an attempt to 

fly undetected to the area where the mines are laid with either a low 

or high altitude tactic flight. The shapes are scored for accuracy as 

they enter the water and the aircrew is later debriefed on their 

performance. The training shapes are inert (no detonations occur) and 

expendable. Mine laying operations are regularly conducted in the water 

in the vicinity of BT-9.

Bombing Exercises

    The purpose of bombing exercises is to train pilots in destroying 

or disabling enemy ships or boats. During training, fixed wing or 

rotary wing aircraft deliver bombs against surface maritime targets at 

BT-9 or BT-11, day or night, using either unguided or precision-guided 

munitions. Unguided munitions include MK-76 and BDU-45 inert training 

bombs, and MK-80 series of inert bombs (no cluster munitions 

authorized). Precision-guided munitions consist of laser-guided bombs 

(inert) and laser-guided training rounds (inert). Typically, two 

aircraft approach the target (principally BT-9) from an altitude of 

approximately 914 m (3,000 ft) up to 4,572 m (15,000 ft) and, when on 

an established range, the aircraft adhere to designated ingress and 

egress routes. Typical bomb release altitude is 914 m (3,000 ft) for 

unguided munitions or above 4,572 m (15,000 ft) and in excess of 1.8 km 

(1 nm) for precision-guided munitions. However, the lowest minimum 

altitude for ordnance delivery (inert bombs) would be 152 m (500 ft).

    Onboard laser designators or laser designators from a support 

aircraft or ground support personnel are used to illuminate certified 

targets for use when using laser guided weapons. Due to target 

maintenance issues, live bombs have not been dropped at the BT-9 

targets for the past few years although these munitions are authorized 

for use. For the effective IHA timeframe, no live bombs would be 

utilized. Live rockets and grenades; however, have been expended at BT-

9.

    Air-to-Surface bombing exercises have the potential to occur on a 

daily basis. The standard sortie consists of two aircraft per bombing 

run. The frequency of these exercises is dependent on squadron level 

training requirements, deployment status, and range availability; 

therefore, there is no set pattern or specific time of year or month 

when this training occurs. Normal operating hours for the range are 

0800-2300, Monday through Friday; however, the range is available for 

use 365 days per year.

Rocket Exercises

    Rocket exercises are carried out similar to bombing exercises. 

Fixed- and rotary-wing aircraft crews launch rockets at surface 

maritime targets, day and night, to train for destroying or disabling 

enemy ships or boats. These operations employ 2.75-inch and 5-inch 

rockets.

    The average number of rockets delivered per sortie is approximately 

14. As with the bombing exercise, there is no set level or pattern of 

amount of sorties conducted.

Gunnery Exercises

    During gunnery training, fixed- and rotary-wing aircraft expend 

smaller munitions targeted at the BTs with the purpose of hitting them. 

However, some small arms may land in the water. Rotary wing exercises 

involve either CH-53, UH-1, CH-46, MV-22, or H-60 rotary-wing aircraft 

with mounted 7.62 mm or .50 cal machine guns. Each gunner expends 

approximately 800 rounds of 7.62 mm and 200 rounds of .50 cal 

ammunition in each exercise. These may be live or inert.

    Fixed wing gunnery exercises involve the flight of two aircraft 

that begin to descend to the target from an altitude of approximately 

914 meters (m) (3,000 feet [ft]) while still several miles away. Within 

a distance of 1,219 m (4,000 ft) from the target, each aircraft fires a 

burst of approximately 30 rounds before reaching an altitude of 305 m 

(1,000 ft), then breaks off and repositions for another strafing run 

until each aircraft expends its exercise ordnance allowance of 

approximately 250 rounds. In total, about 8-12 passes are made by each 

aircraft per exercise. Typically these fixed wing exercise events 

involve an F/A-18 and AH-1 with Vulcan M61A1/A2, 20 mm cannon; AV-8 

with GAU-12, 25 mm cannon.

Munition Descriptions

    A complete list of the ordnance authorized for use at BT-9 and BT-

11 can be found in Tables 2 and 3, respectively. There are several 

varieties and net explosive weights (for live munition used at BT-9) 

can vary according to the variety. All practice bombs are inert and 

used to simulate the same ballistic properties of service type bombs. 

They are manufactured as either solid cast metal bodies or thin sheet 

metal containers. Since practice bombs contain no explosive filler, a 

practice bomb signal cartridge (smoke) is used for visual observation 

of weapon target



[[Page 32402]]



impact. Practice bombs provide a low cost training device for pilot and 

ground handling crews. Due to the relatively small amount of explosive 

material in practice bombs (small signal charge), the availability of 

ranges for training is greatly increased.

    When a high explosive detonates, it is converted almost instantly 

into a gas at very high pressure and temperature. Under the pressure of 

the gases thus generated, the weapon case expands and breaks into 

fragments. The air surrounding the casing is compressed and shock 

(blast) wave is transmitted into it. Typical initial values for a high-

explosive weapon are 200 kilobars of pressure (1 bar = 1 atmosphere) 

and 5,000 degrees Celsius. There are five types of explosive sources 

used at BT-9: 2.75'' Rocket High Explosives, 5'' Rocket High 

Explosives, 30 mm High Explosives, 40 mm High Explosives, and G911 

grenades. No live munitions are used at BT-11.



                                 Table 2--Description of Munitions Used at BT-9

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

               Ordnance                      Description                      Net explosive weight

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

MK 76 Practice Bomb (inert)..........  25-pound teardrop-       (of signal cartridge) varies, maximum 0.083800

                                        shaped cast metal        lbs.

                                        bomb, with a bore tube

                                        for installation of a

                                        signal cartridge.

BDU 33 Practice Bomb (inert).........  Air Force MK 76          same as above.

                                        practice bomb.

BDU 48 Practice Bomb (inert).........  10-pound metal           same as above.

                                        cylindrical bomb body

                                        with a bore tube for

                                        installation of a

                                        signal cartridge.

BDU 45 Practice Bomb (inert).........  500-pound metal bomb     (of signal cartridges) total 0.1676 lbs.

                                        either sand or water

                                        filled. Two signal

                                        cartridges.

BDU 50 Practice Bomb (inert).........  500-pound metal bomb     same as above.

                                        either sand or water

                                        filled. Two signal

                                        cartridges.

MK 81 Practice Bomb (inert)..........  250-pound bomb.........  0

MK 82 Practice Bomb (inert)..........  500-pound bomb.........  0

MK 83 Practice Bomb (inert)..........  1000-pound bomb          0.1676 lbs.

                                        configured like BDU 45.

MK 84 Practice Bomb (inert) (special   2000-pound bomb          0.1676 lbs.

 exception use only).                   configured like BDU 45.

2.75-inch (inert)....................  Unguided 2.75 inch       0

                                        diameter rocket.

5-inch Zuni (inert)..................  Unguided 5 inch          0

                                        diameter rocket.

5-inch Zuni (live)...................  Unguided 5-inch          15 lbs.

                                        diameter rocket.

2.75wp (inert).......................  2.75-inch rocket         0

                                        containing white

                                        phosphorous.

2.75HE...............................  High Explosive, 2.75     4.8 lbs.

                                        inch rocket.

0.50 cal (inert).....................  Machine gun rounds.....  0

7.62 mm (inert)......................

20 mm (inert)........................

25 mm (inert)........................

30 mm (inert)........................

40 mm (inert)........................

25 mm HE (live)......................  High Explosive           0.269 lbs.

                                        Incendiary, Live

                                        machine gun rounds.

Self Protection Flare................  Aerial flare...........  0

Chaff................................  18-pound chaff canister  0

LUU-2................................  30-pound high intensity  0

                                        illumination flare.

Laser Guided Training Round (LGTR)     89-pound inert training  0

 (inert).                               bomblet.

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





             Table 3--Description of Munitions Used at BT-11

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

             Ordnance                            Description

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

MK 76 Practice Bomb...............  25-pound teardrop-shaped cast metal

                                     bomb body, with a bore tube for

                                     installation of a signal cartridge.

BDU 33 Practice Bomb..............  Air Force designation for MK 76

                                     practice bomb.

BDU 48 Practice Bomb..............  10-pound metal cylindrical bomb body

                                     with a bore tube for installation

                                     of a signal cartridge.

BDU 45 Practice Bomb..............  500-pound metal bomb body either

                                     sand or water filled. Configured

                                     with either low drag conical tail

                                     fins or high drag tail fins for

                                     retarded weapons delivery. Two

                                     signal cartridges installed.

MK 81 Practice Bomb...............  250-pound inert bomb.

MK 82 Practice Bomb...............  500-pound inert bomb.

2.75-inch.........................  Unguided 2.75 inch diameter rocket.

5-inch Zuni.......................  5 inch diameter rocket.

WP-2.75-inch......................  White phosphorous 7-pound rocket.

0.50 cal..........................  Inert machine gun rounds.

7.62 mm...........................

5.56 mm...........................

20 mm.............................

30 mm.............................

40 mm.............................

TOW...............................  Wire guided 56-pound anti-tank

                                     missile.

Self Protection Flare.............  Aerial flare.

SMD SAMS..........................  1.5-pound smoking flare.

LUU-2.............................  30-pound high-intensity illumination

                                     flare.

Laser Guided Training Round (LGTR)  89-pound inert training bomblet.

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





[[Page 32403]]



    The amounts of all ordnance to be expended at BT-9 and BT-11 (both 

surface-to-surface and air-to-surface) are 897,932 and 1,109,955 

rounds, respectively (see Table 4 and 5 below).



                      Table 4--Amount of Live and Inert Munitions Expended at BT-9 per Year

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

                                                                 Proposed number of explosive

           Proposed munitions \1\              Proposed total   rounds having an impact on the    Net explosive

                                              number of rounds               water                 weight (lb)

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

Small Arms Rounds Excluding .50 cal.........           525,610  N/A...........................               N/A

.50 Cal.....................................           257,067  N/A...........................               N/A

Large Arms Rounds--Live.....................            12,592  30 mm HE: 3,120...............            0.1019

                                              ................  40 mm HE: 9,472                           0.1199

Large Arms Rounds--Inert....................            93,024  N/A...........................               N/A

Rockets--Live...............................               241  2.75'' Rocket: 184............               4.8

                                                                5'' Rocket: 57................              15.0

Rockets--Inert..............................               703  N/A...........................               N/A

Bombs and Grenades--Live....................               144  G911 Grenade: 144.............               0.5

Bombs and Grenades--Inert...................             4,055  N/A...........................               N/A

Pyrotechnics................................             4,496  N/A...........................               N/A

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

    Total...................................           897,932  12,977........................               N/A

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

\1\ Munitions may be expended from aircraft or small boats.





          Table 5--Amount of Inert Munitions Expended at BT-11

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

                                                         Proposed total

                Proposed munitions \1\                  number of rounds

                                                               \2\

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

Small Arms Rounds Excluding .50 Cal...................           507,812

.50 Cal...............................................           326,234

Large Arms Rounds.....................................           240,334

Rockets...............................................             4,549

Bombs and Grenades....................................            22,114

Pyrotechnics..........................................             8,912

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

    Total.............................................         1,109,955

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

\1\ Munitions may be expended from aircraft or small boats.

\2\ Munitions estimated using FY 2007 CURRS data on a per sortie-

  operation basis.



Description of Marine Mammals in the Area of the Specified Activity



    Forty marine mammal species occur within the nearshore and offshore 

waters of North Carolina; however, the majority of these species are 

solely oceanic in distribution. Only one marine mammal species, the 

bottlenose dolphin, has been repeatedly sighted in Pamlico Sound, while 

an additional species, the endangered West Indian manatee (Trichechus 

manatus), has been sighted rarely (Lefebvre et al., 2001; DoN 2003). 

The U.S. Fish and Wildlife Service oversees management of the manatee; 

therefore, authorization to harass manatees would not be included in 

any NMFS' authorization and will not be discussed further.

    No sightings of the endangered North Atlantic right whale 

(Eubalaena glacialis) or other large whales have been observed within 

Pamlico Sound or in vicinity of the BTs (Kenney 2006). No suitable 

habitat exists for these species in the shallow Pamlico Sound or BT 

vicinity; therefore, whales would not be affected by the specified 

activities and will not be discussed further. Other dolphins, such as 

Atlantic spotted (Stenella frontalis) and common dolphins (Delphinus 

delphis), are oceanic in distribution and do not venture into the 

shallow, brackish waters of southern Pamlico Sound. Therefore, the 

specified activity has the potential to affect one marine mammal 

species under NMFS' jurisdiction: the bottlenose dolphin.

    Coastal (or nearshore) and offshore stocks of bottlenose dolphins 

in the Western North Atlantic can be distinguished by genetics, diet, 

blood characteristics, and outward appearance (Duffield et al., 1983; 

Hersh and Duffield, 1990; Mead and Potter, 1995; Curry and Smith, 

1997). Initially, a single stock of coastal morphotype bottlenose 

dolphins was thought to migrate seasonally between New Jersey (summer 

months) and central Florida based on seasonal patterns in strandings 

during a large scale mortality event occurring during 1987-1988 (Scott 

et al., 1988). However, re-analysis of stranding data (McLellan et al., 

2003) and extensive analysis of genetic, photo-identification, 

satellite telemetry, and stable isotope studies demonstrate a complex 

mosaic of coastal bottlenose dolphin stocks (NMFS 2001) which may be 

migratory or resident (they do not migrate and occur within an area 

year round). Four out of the seven designated coastal stocks may occur 

in North Carolina waters at some part of the year: the Northern 

Migratory stock (NM; winter); the Southern Migratory stock (SM; 

winter); the Northern North Carolina Estuarine stock (NNCE; resident, 

year round); and the more recently identified Southern North Carolina 

stock (SNC; resident, year round). Stable isotope depleted oxygen 

signature (hypoxic conditions routinely develops during summer in North 

Carolina waters) (Cortese, 2000), satellite telemetry, and photo-

identification (NMFS, 2001) support stock structure analysis. Dolphins 

encountered at the BTs likely belong to the NNCE and SNC stock; 

however, this may not always be the case. NMFS' 2008 stock assessment 

report provides further detail on stock delineation. All stocks 

discussed here are considered depleted under the MMPA (Waring et al., 

2007).

    NMFS provides abundance estimates for the four aforementioned 

migratory and resident coastal stocks in its 2008 stock assessment 

report; however, these estimates are based solely from summer aerial 

surveys. The size of the NNCE stock is technically considered 

``unknown''; however, Read et al., (2003) provided a population 

estimate of 919 (95 percent CI 730-1,190) (Waring et al., 2009). The 

population estimate for the SNC stock is 4,818, respectively. From July 

2004 through April 2006, the NMFS' SEFSC conducted 41 aerial surveys to 

document the seasonal distribution and estimated density of sea turtles 

and dolphins within Core Sound and portions of Pamlico Sound, and 

coastal waters extending one mile offshore (Goodman et al., 2007). 

Pamlico Sound was divided into two survey areas: western (encompassing 

BT-9 and BT-11) and eastern (including Core Sound and the eastern 

portion of restricted air space R-5306). In total, 281 dolphins were 

sighted in the western range. To account for animals likely missed 

during sightings (i.e.,



[[Page 32404]]



those below the surface), Goodman et al. (2007) estimate that, in 

reality, 415 dolphins were present. Densities for bottlenose dolphins 

in the western part of Pamlico Sound were calculated to be 0.0272/km\2\ 

in winter; 0.2158/km\2\ in autumn; 0.0371/km\2\ in summer; and 0.0946/

km\2\ in summer (Goodman et al., 2007). Dolphins were sighted 

throughout the entire range when mean sea surface temperature (SST) was 

7.60 [deg]C to 30.82 [deg]C, with fewer dolphins sighted as water 

temperatures increased. Like in Mayer (2003), dolphins were found in 

higher numbers around BT-11, a range where no live firing occurs.

    In 2000, Duke University Marine Lab (DUML), conducted a boat-based 

mark-recapture survey throughout the estuaries, bays and sounds of 

North Carolina (Read et al., 2003). This summer survey yielded a 

dolphin density of 0.183/km\2\ (0.071 mi;\2\) based on an estimate of 

919 dolphins for the northern inshore waters divided by an estimated 

5,015 km\2\ (1,936 mi\2\) survey area. Additionally, from July 2002-

June 2003, the USMC supported DUML to conduct dolphin surveys 

specifically in and around BT-9 and BT-11. During these surveys, one 

sighting in the restricted area surrounding BT-9 and two sightings in 

proximity to BT-11 were observed, as well as seven sightings in waters 

adjacent to the BTs. In total, 276 bottlenose dolphins were sighted 

ranging in group size from two to 70 animals with mean dolphin density 

in BT-11 more than twice as large as the density of any of the other 

areas; however, the daily densities were not significantly different 

(Maher, 2003). Estimated dolphin density at BT-9 and BT-11 based on 

these surveys were calculated to be 0.11 dolphins/km\2\, and 1.23 

dolphins/km\2\, respectively, based on boat surveys conducted from July 

2002 through June 2003 (excluding April, May, Sept. and Jan.). However, 

the USMC choose to estimate take of dolphins based on the higher 

density reported from the summer 2000 surveys (0.183/km\2\). Although 

the aerial surveys were conducted year round and therefore provide for 

seasonal density estimates, the average year-round density from the 

aerial surveys is 0.0936, lower than the 0.183/km\2\ density chosen to 

calculate take for purposes of this MMPA authorization. Additionally, 

Goodman et al. (2007) acknowledged that boat based density estimates 

may be more accurate than the uncorrected estimates derived from the 

aerial surveys.

    In Pamlico Sound, bottlenose dolphins concentrate in shallow water 

habitats along shorelines, and few, if any, individuals are present in 

the central portions of the sounds (Gannon, 2003; Read et al., 2003a, 

2003b). The dolphins utilize shallow habitats, such as tributary creeks 

and the edges of the Neuse River, where the bottom depth is less than 

3.5 m (Gannon, 2003). Fine-scale distribution of dolphins seems to 

relate to the presence of topography or vertical structure, such as the 

steeply-sloping bottom near the shore and oyster reefs, which may be 

used to facilitate prey capture (Gannon, 2003). Results of a passive 

acoustic monitoring effort conducted from 2006-2007 by Duke University 

researchers validated this information. Vocalizations of dolphins in 

the BT-11 vicinity were higher in August and September than 

vocalization detection at BT-9, an open water area (Read et al., 2007). 

Additionally, detected vocalizations of dolphins were more frequent at 

night for the BT-9 area and during early morning hours at BT-11.

    Unlike migrating whales which display strong temporal foraging and 

mating/birthing periods, many bottlenose dolphins in Pamlico Sound are 

residents and mate year round. However, dolphins in the southeast U.S. 

do display some reproductive seasonality. Based on neonate stranding 

records, sighting data, and births by known females, the populations of 

dolphins that frequent the North Carolina estuarine waters have calving 

peaks in spring but calving continues throughout the summer and is 

followed by a smaller number of fall births (Thayer et al., 2003).

    Bottlenose dolphins can typically hear within a broad frequency 

range of 0.04 to 160 kHz (Au, 1993; Turl, 1993). Electrophysiological 

experiments suggest that the bottlenose dolphin brain has a dual 

analysis system: one specialized for ultrasonic clicks and another for 

lower-frequency sounds, such as whistles (Ridgway, 2000). Scientists 

have reported a range of highest sensitivity between 25 and 70 kHz, 

with peaks in sensitivity at 25 and 50 kHz (Nachtigall et al., 2000). 

Recent research on the same individuals indicates that auditory 

thresholds obtained by electrophysiological methods correlate well with 

those obtained in behavior studies, except at some lower (10 kHz) and 

higher (80 and 100 kHz) frequencies (Finneran and Houser, 2006).

    Sounds emitted by bottlenose dolphins have been classified into two 

broad categories: pulsed sounds (including clicks and burst-pulses) and 

narrow-band continuous sounds (whistles), which usually are frequency 

modulated. Clicks have a dominant frequency range of 110 to 130 

kiloHertz (kHz) and a source level of 218 to 228 dB re 1 [mu]Pa (peak-

to-peak) (Au, 1993) and 3.4 to 14.5 kHz at 125 to 173 dB re 1 [mu]Pa 

(peak-to-peak) (Ketten, 1998). Whistles are primarily associated with 

communication and can serve to identify specific individuals (i.e., 

signature whistles) (Caldwell and Caldwell, 1965; Janik et al., 2006). 

Up to 52 percent of whistles produced by bottlenose dolphin groups with 

mother-calf pairs can be classified as signature whistles (Cook et al., 

2004). Sound production is also influenced by group type (single or 

multiple individuals), habitat, and behavior (Nowacek, 2005). Bray 

calls (low-frequency vocalizations; majority of energy below 4 kHz), 

for example, are used when capturing fish, specifically sea trout 

(Salmo trutta) and Atlantic salmon (Salmo salar), in some regions 

(i.e., Moray Firth, Scotland) (Janik, 2000). Additionally, whistle 

production has been observed to increase while feeding (Acevedo-

Guti[eacute]rrez and Stienessen, 2004; Cook et al., 2004).



Potential Effects on Marine Mammals



    As mentioned previously, with respect to military readiness 

activities, Section 3(18)(B) of the MMPA defines ``harassment'' as: (i) 

Any act that injures or has the significant potential to injure a 

marine mammal or marine mammal stock in the wild [Level A Harassment]; 

or (ii) any act that disturbs or is likely to disturb a marine mammal 

or marine mammal stock in the wild by causing disruption of natural 

behavioral patterns, including, but not limited to, migration, 

surfacing, nursing, breeding, feeding, or sheltering, to a point where 

such behavioral patterns are abandoned or significantly altered [Level 

B Harassment].

    According the application, the USMC has concluded that harassment 

to marine mammals may occur incidental to munitions firing noise and 

pressure at the BTs. These military readiness activities would result 

in increased noise levels, explosions, and munition debris within 

bottlenose dolphin habitat. NMFS also considered the potential for 

harassment from vessel and aircraft operation. The USMC's and NMFS' 

analysis of potential impacts from these factors are outlined below.



Anthropogenic Sound



    Marine mammals respond to various types of anthropogenic sounds 

introduced in the ocean environment. Responses are highly variable and 

depend on a suite of internal and external factors which in turn 

results in varying degrees of significance (NRC, 2003; Southall et al., 

2007). Internal



[[Page 32405]]



factors include: (1) Individual hearing sensitivity, activity pattern, 

and motivational and behavioral state (e.g., feeding, traveling) at the 

time it receives the stimulus; (2) past exposure of the animal to the 

noise, which may lead to habituation or sensitization; (3) individual 

noise tolerance; and (4) demographic factors such as age, sex, and 

presence of dependent offspring. External factors include: (1) Non-

acoustic characteristics of the sound source (e.g., if it is moving or 

stationary); (2) environmental variables (e.g., substrate) which 

influence sound transmission; and (3) habitat characteristics and 

location (e.g., open ocean vs. confined area). To determine whether an 

animal perceives the sound, the received level, frequency, and duration 

of the sound are compared to ambient noise levels and the species' 

hearing sensitivity range. That is, if the frequency of an introduced 

sound is outside of the species' frequency hearing range, it can not be 

heard. Similarly, if the frequency is on the upper or lower end of the 

species hearing range, the sound must be louder in order to be heard.

    Marine mammal responses to anthropogenic noise are typically subtle 

and can include visible and acoustic reactions such as avoidance, 

altered dive patterns and cessation of pre-exposure activities and 

vocalization reactions such as increasing or decreasing call rates or 

shifting call frequency. Responses can also be unobservable, such as 

stress hormone production and auditory trauma or fatigue. It is not 

always known how these behavioral and physiological responses relate to 

significant effects (e.g., long-term effects or individual/population 

consequences); however, individuals and populations can be monitored to 

provide some insight into the consequences of exposing marine mammals 

to noise. For example, Haviland-Howell et al (2007) compared sighting 

rates of bottlenose dolphins within the Wilmington, NC stretch of the 

Atlantic Intracoastal Waterway (ICW) on weekends, when recreational 

vessel traffic was high, to weekdays, when vessel traffic was 

relatively minimal. The authors found that dolphins were less often 

sighted in the ICW during times of increased boat traffic (i.e., on 

weekends) and theorized that because vessel noise falls within the 

frequencies of dolphin communication whistles and primary energy of 

most fish vocalizations, the continuous vessel traffic along that 

stretch of the ICW could result in social and foraging impacts. 

However, the extent to which these impacts affect individual health and 

population structure is unknown.

    A full assessment of marine mammal responses and disturbances when 

exposed to anthropogenic sound can be found in NMFS' proposed 

rulemaking for the Navy Cherry Point Range Complex (74 FR 11057, March 

16, 2009). In summary, sound exposure may result in physiological 

impacts, stress responses, and behavioral responses which could affect 

proximate or ultimate life functions. Proximate life history functions 

are the functions that the animal is engaged in at the time of acoustic 

exposure. The ultimate life functions are those that enable an animal 

to contribute to the population (or stock, or species, etc.).

I. Physiology-Hearing Threshold Shift

    In mammals, high-intensity sound may rupture the eardrum, damage 

the small bones in the middle ear, or over stimulate the 

electromechanical hair cells that convert the fluid motions caused by 

sound into neural impulses that are sent to the brain. Lower level 

exposures may cause a loss of hearing sensitivity, termed a threshold 

shift (TS) (Miller, 1974). Incidence of TS may be either permanent, 

referred to as permanent threshold shift (PTS), or temporary, referred 

to as temporary threshold shift (TTS). The amplitude, duration, 

frequency, and 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, generally, so does the amount of TS and recovery time. Human 

non-impulsive noise exposure guidelines are based on exposures of equal 

energy (the same SEL) producing equal amounts of hearing impairment 

regardless of how the sound energy is distributed in time (NIOSH 1998). 

Until recently, previous marine mammal TTS studies have also generally 

supported this equal energy relationship (Southall et al., 2007). Three 

newer studies, two by Mooney et al. (2009a, 2009b) on a single 

bottlenose dolphin either exposed to playbacks of Navy MFAS or octave-

band noise (4-8 kHz) and one by Kastak et al. (2007) on a single 

California sea lion exposed to airborne octave-band noise (centered at 

2.5 kHz), concluded that for all noise exposure situations the equal 

energy relationship may not be the best indicator to predict TTS onset 

levels. Generally, with sound exposures of equal energy, those that 

were quieter (lower sound pressure level [SPL]) with longer duration 

were found to induce TTS onset more than those of louder (higher SPL) 

and shorter duration (more similar to noise from AS Cherry Point 

exercises). 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). 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). However, these studies highlight the inherent complexity of 

predicting TTS onset in marine mammals, as well as the importance of 

considering exposure duration when assessing potential impacts.

    PTS consists of non-recoverable physical damage to the sound 

receptors in the ear, which can include total or partial deafness, or 

an impaired ability to hear sounds in specific frequency ranges; PTS is 

considered Level A harassment. TTS is recoverable and is considered to 

result from temporary, non-injurious impacts to hearing-related 

tissues; TTS is considered Level B harassment.



Permanent Threshold Shift



    Auditory trauma represents direct mechanical injury to hearing 

related structures, including tympanic membrane rupture, 

disarticulation of the middle ear ossicles, and trauma to the inner ear 

structures such as the organ of Corti and the associated hair cells. 

Auditory trauma is irreversible and considered to be an injury that 

could result in PTS. PTS results from exposure to intense sounds that 

cause a permanent loss of inner or outer cochlear hair cells or exceed 

the elastic limits of certain tissues and membranes in the middle and 

inner ears and result in changes in the chemical composition of the 

inner ear fluids. In some cases, there can be total or partial deafness 

across all frequencies, whereas in other cases, the animal has an 

impaired ability to hear sounds in specific frequency ranges. There is 

no empirical data for onset of PTS in any marine mammal, and therefore, 

PTS- onset must be estimated from TTS-onset measurements and from the 

rate of TTS growth with increasing exposure levels above the level 

eliciting TTS-onset. PTS is presumed to be likely if the hearing 

threshold is reduced by >= 40 dB (i.e., 40 dB of TTS). Relationships 

between TTS and PTS thresholds have not been studied in marine mammals, 

but are assumed to be similar to those in humans and other terrestrial 

mammals.



[[Page 32406]]



Temporary Threshold Shift



    TTS is the mildest form of hearing impairment that can occur during 

exposure to a loud sound (Kryter, 1985). Southall et al. (2007) 

indicate that although PTS is a tissue injury, TTS is not because the 

reduced hearing sensitivity following exposure to intense sound results 

primarily from fatigue, not loss, of cochlear hair cells and supporting 

structures and is reversible. Accordingly, NMFS classifies TTS as Level 

B Harassment, not Level A Harassment (injury); however, NMFS does not 

consider the onset of TTS to be the lowest level at which Level B 

Harassment may occur (see III. Behavior section below).

    Southall et al. (2007) considers a 6 dB TTS (i.e., baseline hearing 

thresholds are elevated by 6 dB) sufficient to be recognized as an 

unequivocal deviation and thus a sufficient definition of TTS onset. 

TTS in bottlenose dolphin hearing have been experimentally induced. For 

example, Finneran et al. (2002) exposed a trained captive bottlenose 

dolphin to a seismic watergun simulator with a single acoustic pulse. 

No TTS was observed in the dolphin at the highest exposure condition 

(peak: 207 kPa [30psi]; peak-to-peak: 228 dB re: 1 microPa; SEL: 188 dB 

re 1 microPa\2\-s). Schludt et al. (2000) demonstrated temporary shifts 

in masked hearing thresholds in five bottlenose dolphins occurring 

generally between 192 and 201 dB rms (192 and 201 dB SEL) after 

exposure to intense, non-pulse, 1-s tones at, 3kHz, 10kHz, and 20 kHz. 

TTS onset occurred at mean sound exposure level of 195 dB rms (195 dB 

SEL). At 0.4 kHz, no subjects exhibited threshold shifts after SPL 

exposures of 193dB re: 1 microPa (192 dB re: 1 microPa\2\-s). In the 

same study, at 75 kHz, one dolphin exhibited a TTS after exposure at 

182 dB SPL re: 1 microPa but not at higher exposure levels. Another 

dolphin experienced no threshold shift after exposure to maximum SPL 

levels of 193 dB re: 1 microPa at the same frequency. Frequencies of 

explosives used at MCAS Cherry Point range from 1-25 kHz; the range 

where dolphin TTS onset occurred at 195 dB rms in the Schludt et al. 

(2000) study.

    Preliminary research indicates that TTS and recovery after noise 

exposure are frequency dependent and that an inverse relationship 

exists between exposure time and sound pressure level associated with 

exposure (Mooney et al., 2005; Mooney, 2006). For example, Nachtigall 

et al. (2003) measured TTS in a bottlenose dolphin and found an average 

11 dB shift following a 30 minute net exposure to OBN at a 7.5 kHz 

center frequency (max SPL of 179 dB re: 1 microPa; SEL: 212- 214 dB 

re:1 microPa\2\-s). No TTS was observed after exposure to the same 

duration and frequency noise with maximum SPLs of 165 and 171 dB re:1 

microPa. After 50 minutes of exposure to the same 7.5 kHz frequency 

OBN, Natchigall et al. (2004) measured a 4 -8 dB shift (max SPL: 160dB 

re 1microPa; SEL: 193-195 dB re:1 microPa\2\-s). Finneran et al. (2005) 

concluded that a sound exposure level of 195 dB re 1 [mu]Pa\2\-s is a 

reasonable threshold for the onset of TTS in bottlenose dolphins 

exposed to mid-frequency tones.

II. Stress Response

    An acoustic source is considered a potential stressor if, by its 

action on the animal, via auditory or non-auditory means, it may 

produce a stress response in the animal. Here, the stress response will 

refer to an increase in energetic expenditure that results from 

exposure to the stressor and which is predominantly characterized by 

either the stimulation of the sympathetic nervous system (SNS) or the 

hypothalamic-pituitary-adrenal (HPA) axis (Reeder and Kramer, 2005). 

The SNS response to a stressor is immediate and acute and is 

characterized by the release of the catecholamine neurohormones 

norepinephrine and epinephrine (i.e., adrenaline). These hormones 

produce elevations in the heart and respiration rate, increase 

awareness, and increase the availability of glucose and lipids for 

energy. The HPA response is ultimately defined by increases in the 

secretion of the glucocorticoid steroid hormones, predominantly 

cortisol in mammals. The presence and magnitude of a stress response in 

an animal depends on a number of factors. These include the animal's 

life history stage (e.g., neonate, juvenile, adult), the environmental 

conditions, reproductive or developmental state, and experience with 

the stressor. Not only will these factors be subject to individual 

variation, but they will also vary within an individual over time. The 

stress response may or may not result in a behavioral change, depending 

on the characteristics of the exposed animal. However, provided a 

stress response occurs, we assume that some contribution is made to the 

animal's allostatic load. Any immediate effect of exposure that 

produces an injury is assumed to also produce a stress response and 

contribute to the allostatic load. Allostasis is the ability of an 

animal to maintain stability through change by adjusting its physiology 

in response to both predictable and unpredictable events (McEwen and 

Wingfield, 2003). If the acoustic source does not produce tissue 

effects, is not perceived by the animal, or does not produce a stress 

response by any other means, we assume that the exposure does not 

contribute to the allostatic load. Additionally, without a stress 

response or auditory masking, it is assumed that there can be no 

behavioral change.

III. Behavior

    Changes in marine mammal behavior in response to anthropogenic 

noise may include altered travel directions, increased swimming speeds, 

changes in dive, surfacing, respiration and feeding patterns, and 

changes in vocalizations. As described above, lower level physiological 

stress responses could also co-occur with altered behavior; however, 

stress responses are more difficult to detect and fewer data exist 

relative to specific received levels of sound.



Acoustic Masking



    Anthropogenic noise can interfere with, or mask, detection of 

acoustic signals such as communication calls, echolocation, and 

environmental sounds important to marine mammals. Southall et al. 

(2007) defines auditory masking as the partial or complete reduction in 

the audibility of signals due to the presence of interfering noise with 

the degree of masking depending on the spectral, temporal, and spatial 

relationships between signals and masking noise, as well as the 

respective received levels. Masking of sender communication space can 

be considered as the amount of change in a sender's communication space 

caused by the presence of other sounds, relative to a pre-industrial 

ambient noise condition (Clark et al., in press).

    Unlike auditory fatigue, which always results in a stress response 

because the sensory tissues are being stimulated beyond their normal 

physiological range, masking may or may not result in a stress 

response, depending on the degree and duration of the masking effect. 

Masking may also result in a unique circumstance where an animal's 

ability to detect other sounds is compromised without the animal's 

knowledge. This could conceivably result in sensory impairment and 

subsequent behavior change; in this case, the change in behavior is the 

lack of a response that would normally be made if sensory impairment 

did not occur. For this reason, masking also may lead directly to 

behavior change without first causing a stress response.



[[Page 32407]]



Projecting noise into the marine environment which causes acoustic 

masking is considered Level B harassment as it can disrupt natural 

behavioral patterns by interrupting or limiting the marine mammal's 

receipt or transmittal of important information or environmental cues. 

To compensate for masking, marine mammals, including bottlenose 

dolphins, are known to increase their levels of vocalization as a 

function of background noise by increasing call repetition and 

amplitude, shifting calls higher frequencies, and/or changing the 

structure of call content (Lesage et al., 1999; Scheifele et al., 2005; 

McIwem, 2006).

    While it may occur temporarily, NMFS does not expect auditory 

masking to result in detrimental impacts to an individual's or 

population's survival, fitness, or reproductive success. Dolphins are 

not confined to the BT ranges; allowing for movement out of area to 

avoid masking impacts. The USMC would also conduct visual sweeps of the 

area before any training exercise and implement training delay 

mitigation measures if a dolphin is sighted within designated zones 

(see Proposed Mitigation Measures section below). As discussed 

previously, the USMC has been working with DUML to collect baseline 

information on dolphins in Pamlico Sound, specifically dolphin 

abundance and habitat use around the BTs. The USMC has also recently 

accepted a DUML proposal to investigate methods of dolphin acoustic 

detection around the BTs. NMFS would encourage the USMC to expand 

acoustic investigations to include the impacts of training exercises on 

vocalization properties (e.g., call content, duration, frequency) and 

masking (e.g., communication and foraging impairment) of the affected 

population of dolphins in Pamlico Sound.



Assessment of Marine Mammal Impacts From Explosive Ordnances



    MCAS Cherry Point plans to use five types of explosive sources 

during its training exercises: 2.75'' Rocket High Explosives, 5'' 

Rocket High Explosives, 30 mm High Explosives, 40 mm High Explosives, 

and G911 grenades. The underwater explosions from these weapons would 

send a shock wave and blast noise through the water, release gaseous 

by-products, create an oscillating bubble, and cause a plume of water 

to shoot up from the water surface. The shock wave and blast noise are 

of most concern to marine animals. In general, potential impacts from 

explosive detonations can range from brief effects (such as short term 

behavioral disturbance), tactile perception, physical discomfort, 

slight injury of the internal organs and the auditory system, to death 

of the animal (Yelverton et al., 1973; O'Keeffe and Young, 1984; DoN, 

2001).

    Explosives produce significant acoustic energy across several 

frequency decades of bandwidth (i.e., broadband). Propagation loss is 

sufficiently sensitive to frequency as to require m