[Federal Register Volume 78, Number 107 (Tuesday, June 4, 2013)]
[Notices]
[Pages 33357-33369]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-13119]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XC561


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Conducting Maritime Strike 
Operations by Eglin Air Force Base in the Gulf of Mexico

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 received an application from the U.S. Air Force (USAF), 
Eglin Air Force Base (Eglin AFB), for an Incidental Harassment 
Authorization (IHA) to take marine mammals, by harassment, incidental 
to Maritime Strike Operations in the Gulf of Mexico (GOM). The USAF's 
activities are considered military readiness activities. Pursuant to 
the Marine Mammal Protection Act (MMPA), NMFS requests comments on its 
proposal to issue an IHA to Eglin AFB to take, by harassment, several 
species of marine mammal during the specified activity for a period of 
1 year.

DATES: Comments and information must be received no later than July 5, 
2013.

ADDRESSES: Comments on the application should be addressed to Michael 
Payne, Chief, Permits and Conservation Division, Office of Protected 
Resources, National Marine Fisheries Service, 1315 East-West Highway, 
Silver Spring, MD 20910. The mailbox address for providing email 
comments is [email protected]. NMFS is not responsible for email 
comments sent to addresses other than the one provided here. Comments 
sent via email, including all attachments, must not exceed a 10-
megabyte file size.
    Instructions: All comments received are a part of the public record 
and will generally be posted to http://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.
    An electronic copy of the application containing a list of the 
references used in this document and Eglin AFB's Draft Environmental 
Assessment (DEA) 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: http://www.nmfs.noaa.gov/pr/permits/incidental.htm. Documents cited in this 
notice may also be viewed, by appointment, during regular business 
hours, at the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Brian D. Hopper, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct

[[Page 33358]]

the Secretary of Commerce to allow, upon request, the incidental, but 
not intentional, taking of small numbers of marine mammals by U.S. 
citizens who engage in a specified activity (other than commercial 
fishing) within a specified geographical region if certain findings are 
made and either regulations are issued or, if the taking is limited to 
harassment, a notice of a proposed authorization is provided to the 
public for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103 
as ``. . . an impact resulting from the specified activity that cannot 
be reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the U.S. 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 National Defense Authorization Act (NDAA) (Pub. L. 108-136) 
removed the ``small numbers'' and ``specified geographical region'' 
provisions 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

    NMFS received an application on December 11, 2012, from Eglin AFB 
for the taking, by harassment, of marine mammals incidental to Maritime 
Strike Operations within the Eglin Gulf Test and Training Range 
(EGTTR). A revised application was submitted on January 22, 2013, which 
provided updated marine mammal information. The EGTTR is described as 
the airspace over the Gulf of Mexico (GOM) that is controlled by Eglin 
AFB. The planned test location in the EGTTR is Warning Area 151 (W-
151), which is located approximately 17 miles offshore from Santa Rosa 
Island, specifically sub-area W-151A.
    The Maritime Strike operations may potentially impact marine 
mammals at or near the water surface. Marine mammals could potentially 
be harassed, injured, or killed by exploding and non-exploding 
projectiles, and falling debris. However, based on analyses provided in 
the USAF's Draft Environmental Assessment (DEA), Eglin's IHA 
application, including the required mitigation, and for reasons 
discussed later in this document, NMFS does not anticipate that Eglin's 
Maritime Strike exercises will result in any serious injury or 
mortality to marine mammals. Eglin AFB has requested authorization to 
take two cetacean species by Level A and Level B harassment. The 
requested species include: Atlantic bottlenose dolphin (Tursiops 
truncatus) and Atlantic spotted dolphin (Stenella frontalis).

Description of the Specified Activity

    This section describes the Maritime Strike missions that have the 
potential to affect marine mammals present within the test area. 
Maritime Strike operations, a ``military readiness activity'' as 
defined under 16 U.S.C. 703 note, involve detonations above the water, 
near the water surface, and under water within the EGTTR. These 
missions involve multiple types of live munitions identified in Tables 
1 and 2 below. The Maritime Strike operations are described in more 
detail in the following paragraphs.
    The Maritime Strike program was developed in response to the 
increasing threats at sea posed by operations conducted from small 
boats. The first phase of the Maritime Strike program focused on 
detecting and tracking boats using various sensors, simulated weapons 
engagements, and testing with inert munitions. The final phase, and the 
subject of this notice, consists of testing the effectiveness of live 
munitions on small boat threats. The proposed Maritime Strike 
activities would involve the use of multiple types of live munitions in 
the EGTTR against small boat targets, at all desired surface and water 
depth scenarios (maximum depth of 10 feet below the surface) necessary 
to carry out the Tactics Development and Evaluation (TD&E) Program. 
Multiple munitions (bombs, missiles, and gunner rounds) and aircraft 
would be used to meet the objectives of the Maritime Strike program 
(Table 1). Because the tests focus on weapon/target interaction, 
particular aircraft are not specified for a given test as long as it 
meets the delivery parameters. The munitions would be deployed against 
static, towed, and remotely controlled boat targets. Static and 
controlled targets consist of stripped boat hulls with plywood 
simulated crews and systems. Damaged boats would be recovered for data 
collection. Test data collection and operation of remotely controlled 
boats would be conducted from an instrumentation barge anchored on-
site, which would also provide a platform for cameras and weapon-
tracking equipment. Target boats would be positioned 300 to 600 feet 
from the instrument barge, depending on the munition.

                  Table 1--Live Munitions and Aircraft
------------------------------------------------------------------------
                                           Aircraft (not associated with
                Munitions                       specific munitions)
------------------------------------------------------------------------
GBU-10 laser-guided Mk-84 bomb..........  F-16C fighter aircraft.
GBU-24 laser-guided Mk-84 bomb..........  F-16C+ fighter aircraft.
GBU-31 Joint Direct Attack Munition,      F-15E fighter aircraft.
 global positioning system guided Mk-84
 bomb.
GBU-12 laser-guided Mk-82 bomb..........  A-10 fighter aircraft.
GBU-38 Joint Direct Attack Munition,      B-1B bomber aircraft.
 global positioning system guided Mk-82
 bomb.
GBU-54 Laser Joint Direct Attack          B-52H bomber aircraft.
 Munition, laser-guided Mk-82 bomb.
CBU-103/B bomb..........................  MQ-1/9 unmanned aerial
                                           vehicle.
AGM-65E/L/K/G2 Maverick air-to-surface
 missile.

[[Page 33359]]

 
AGM-114 Hellfire air-to-surface missile.
M-117 bomb..............................
PGU-12 high explosive incendiary 30 mm
 rounds.
M56/PGU-28 high explosive incendiary
 20mm rounds.
------------------------------------------------------------------------

    Live testing would include three detonation options: (1) Above the 
water surface; (2) at the water surface; and (3) below the water 
surface (two depths). The number of each type of munition, height or 
depth of detonation, explosive material, and net explosive weight (NEW) 
of each munition is provided in Table 2.

                                                           Table 2--Maritime Strike Munitions
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                             of
          Type of munition                Total  of live      detonations by height/      Warhead--explosive         Net explosive weight per
                                                 munitions                     depth                    material                      munition
--------------------------------------------------------------------------------------------------------------------------------------------------------
GBU-10..............................  1                               Water Surface: all.....  MK-84--Tritonal...........  945 lbs.
GBU-24..............................  1                               Water Surface: all.....  MK-84--Tritonal...........  945 lbs.
GBU-31 (JDAM).......................  13                              Water Surface: 4.......  MK-84--Tritonal...........  945 lbs (MK-84).
                                                                      20 feet AGL: 3.........
                                                                      5 feet underwater: 3...
                                                                      10 feet underwater: 3..
GBU-12..............................  1                               Water Surface: all.....  MK-82--Tritonal...........  192 lbs.
GBU-38 (JDAM).......................  13                              Water Surface: 4.......  MK-82--Tritonal...........  192 lbs (MK-82).
                                                                      20 feet AGL: 3.........
                                                                      5 feet underwater: 3...
                                                                      10 feet underwater: 3..
GBU-54 (LJDAM)......................  1                               Water Surface: all.....  MK-82--Tritonal...........  192 lbs (MK-82).
AGM-65E/L/K/G2 (Maverick)...........  2 each                          Water Surface: all.....  WDU-24/B penetrating blast- 86 lbs.
                                      (8 total)                                                 fragmentation warhead.
CBU-103.............................  4                               Water Surface: all.....  202 Blu-97/B Combined       127 lbs.
                                                                                                Effects Bomblets (0.63
                                                                                                lbs each).
AGM-114 (Hellfire)..................  4                               Water Surface: all.....  High Explosive Anti-Tank    20 lbs.
                                                                                                (HEAT) tandem anti-armor
                                                                                                metal augmented charge.
M-117...............................  6                               20 feet AGL: 3.........  750 lb blast/fragmentation  386 lbs (Tritonal).
                                                                      Water Surface: 3.......   bomb, used the same way
                                                                                                as MK-82--Tritonal.
PGU-12 HEI 30 mm....................  1,000                           Water Surface: all.....  30 x 173 mm caliber with    0.1 lbs.
                                                                                                aluminized RDX explosive.
                                                                                                Designed for GAU-8/A Gun
                                                                                                System.
M56/PGU-28 HEI 20 mm................  1,500                           Water Surface: all.....  20 x 120 mm caliber with    0.02 lbs (Comp A-4 HEI).
                                                                                                aluminized Comp A-4 HEI.
                                                                                                Designed for M61 and M197
                                                                                                Gun System.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Maritime Strike missions are scheduled to occur over an approximate 
two- to three-week period in June 2013. Missions would occur on 
weekdays during daytime hours only, with one or two missions occurring 
per day. All activities would take place within the EGTTR. Activities 
would occur only in Warning Area W-151, and specifically in sub-area W-
151A. W-151A extends approximately 60 nm offshore and has a surface 
area of 2,565 nm\2\ (8,797 km\2\). Water depths range from about 30 to 
350 m and include continental shelf and slope zones; however, most of 
W-151A occurs over the continental shelf, in water depths less than 250 
m. Maritime Strike operations would occur in the shallower, northern 
inshore portion of W-151A, in water depth of about 35 m (see Figure 2-1 
in Eglin's IHA application for a map of the test area).
    To ensure safety, prior to conducting Maritime Strike exercises, 
Eglin would conduct a pre-test target area clearance procedure for 
people and protected species. Support vessels would be deployed around 
a defined safety zone to ensure that commercial and recreational boats 
do not accidentally enter the area. Before delivering the ordnance, 
mission aircraft would make a dry run over the target area to ensure 
that it is clear of commercial and recreational boats (at least two 
aircraft would participate in each test). Due to the limited duration 
of the flyover and potentially high speed and altitude, pilots would 
not be able to survey for marine species. In addition, an E-9A 
surveillance aircraft would survey the target area for nonparticipating 
vessels and other objects on the water surface. Based on the results 
from an acoustic impacts analysis for live ordnance detonations, a 
separate disturbance zone around the target would be established for 
the protection of marine species. The size of the zone would be based 
on the distance to which energy- and pressure-related impacts would 
extend for the various type of ordnance listed in Table 2 and would not 
necessarily be the same size as the human safety zone. Based on the 
acoustic modeling result, the largest possible distance from the target 
would be 3,526 m (2.2 miles), which corresponds to the 177 dB Level B 
harassment threshold for 945 lb NEW munitions detonated at 10 ft 
underwater

[[Page 33360]]

(Table 5). At least two of the support vessels would monitor for marine 
mammals around the target area. Maritime Strike missions would not 
proceed until the target area is determined to be clear of unauthorized 
personnel and protected species.
    In addition to vessel-based monitoring, one to three video cameras 
would be positioned on an instrumentation barge anchored on-site. The 
camera configuration and actual number of cameras used would depend on 
the specific test being conducted. The cameras are typically used for 
situational awareness of the target area and surrounding area, and 
could also be used for monitoring the test site for the presence of 
marine species. A marine species observer would be located in the Eglin 
control tower, along with mission personnel, to monitor the video feed 
before and during test activities.
    After each test, floating targets would be inspected to identify 
and render safe any unexploded ordnance (UXO), including fuzes or 
intact munitions. The Eglin Air Force Explosive Disposal Team would be 
on hand for each test. UXO that cannot be removed would be detonated in 
place, which could result in the sinking of the target vessel. Once the 
area has been cleared for re-entry, test personnel would retrieve 
target debris and marine species observers would survey the area for 
any evidence of adverse impacts to protected species.

Description of Marine Mammals in the Area of the Specified Activity

    There are 28 species of marine mammals documented as occurring in 
Federal waters of the northern GOM. However, species with likely 
occurrence in the test area, and the subject of Eglin's incidental take 
request, are the Atlantic bottlenose dolphin (Tursiops truncatus) and 
Atlantic spotted dolphin (Stenella frontalis). These two species are 
frequently sighted in the northern GOM over the continental shelf, in a 
water depth range that encompasses the Maritime Strike test location 
(Garrison et al., 2008; Navy, 2007; Davis et al., 2000). Dwarf sperm 
whales (Kogia sima) and pygmy sperm whales (K. breviceps) are 
occasionally sighted over the shelf, but are not considered regular 
inhabitants (Davis et al., 2000). The remaining cetacean species are 
primarily considered to occur at or beyond the shelf break (water depth 
of approximately 200 m), and are not included in the proposed take 
authorization. Of the 28 marine mammal species or stocks that may occur 
in the northern GOM, only the sperm whale is listed as endangered under 
the ESA and as depleted under the MMPA. Sperm whale occurrence in the 
area of the proposed activity is unlikely because almost all reported 
sightings have occurred in water depths greater than 200 m. Occurrence 
in the deeper portions of W-151 is possible, although based on reported 
sightings locations, density is expected to low. Therefore, Eglin AFB 
has not requested and NMFS has not proposed the issuance of take 
authorizations for this species. Eglin AFB's MMPA application contains 
a detailed discussion on the description, status, distribution, 
regional distribution, diving behavior, and acoustics and hearing for 
the marine mammals in proposed action area. More detailed information 
on these species can be found in Wursig et al. (2000), Eglin's DEA (see 
ADDRESSES), and in the NMFS U.S. Atlantic and GOM Stock Assessment 
Reports (SARs; Waring et al., 2011). This latter document is available 
at: http://www.nefsc.noaa.gov/publications/tm/tm210/. The West Indian 
manatee (Trichechus manatus) is managed by the U.S. Fish and Wildlife 
Service and is not considered further in this proposed IHA Federal 
Register notice.
    Density estimates for bottlenose dolphin and spotted dolphin were 
derived from two sources. Bottlenose dolphin density estimates were 
derived from a habitat modeling project conducted for portions of the 
EGTTR, including the Maritime Strike project area (Garrison, 2008). 
NMFS developed habitat models using recent aerial survey line transect 
data collected during winter and summer. The surveys covered nearshore 
and continental shelf waters (to a maximum depth of 200 meters), with 
the majority of effort concentrated in waters from the shoreline to 20 
meters depth. Marine species encounter rates during the surveys were 
corrected for sighting probability and the probability that animals 
were available on the surface to be seen. In combination with remotely 
sensed environmental data/habitat parameters (water depth, sea surface 
temperature and chlorophyll), these data were used to develop habitat 
models for cetaceans within the continental shelf and coastal waters of 
the eastern GOM. The technical approach, described as Generalized 
Regression and Spatial Prediction, spatially projects the species-
habitat relationship based on distribution of environmental factors, 
resulting in predicted densities for un-sampled locations and times. 
The spatial density model can therefore be used to predict density in 
unobserved areas and at different times of year based upon the monthly 
composite SST and chlorophyll datasets derived from satellite data. 
Similarly, the spatial density model can be used to predict relative 
density for any sub-region within the surveyed area.
    Garrison (2008) produced bottlenose dolphin density estimates at 
various spatial scales within the EGTTR. At the largest scale, density 
data were aggregated into four principal strata categories: North-
Inshore, North-Offshore, South-Inshore, and South-Offshore. Densities 
for these strata were provided in the published survey report. 
Unpublished densities were also provided for smaller blocks (sub-areas) 
corresponding to airspace units and a number of these sub-areas were 
combined to form larger zones. Densities in these smaller areas were 
provided to Eglin AFB in Excel(copyright) spreadsheets by 
the report author.
    For both large areas and sub-areas, regions occurring entirely 
within waters deeper than 200 meters were excluded from predictions, 
and those straddling the 200 meter isobath were clipped to remove deep 
water areas. In addition, because of limited survey effort, density 
estimates beyond 150 meters water depth are considered invalid. The 
environmental conditions encountered during the survey periods 
(February and July/August) do not necessarily reflect the range of 
conditions potentially encountered throughout the year. In particular, 
the transition seasons of spring (April-May) and fall (October-
November) have a very different range of water temperatures. 
Accordingly, for predictions outside of the survey period or spatial 
range, it is necessary to evaluate the statistical variance in 
predicted values when attempting to apply the model. The coefficient of 
variation (CV) of the predicted quantity is used to measure the 
validity of model predictions. According to Garrison (2008), the best 
predictions have CV values of approximately 0.2. When CVs approach 0.7, 
and particularly when they exceed 1.0, the resulting model predictions 
are extremely uncertain and are considered invalid.
    Based upon the preceding discussion, the bottlenose dolphin density 
estimate used in this document is the median density corresponding to 
sub-area 137 (see Figure 3-1 in Eglin AFB's IHA application). The 
planned Maritime Strike test location lies within this sub-area. Within 
this block, Garrison (2008) provided densities based upon one year 
(2007) and five-year monthly averages for SST and chlorophyll. The 5-
year average is considered preferable. Only densities with a CV rounded 
to 0.7 or lower (i.e., 0.64 and below) were

[[Page 33361]]

considered. The CV for June in this particular block is 0.62. Density 
estimates for bottlenose dolphin are provided in Table 3.
    Atlantic spotted dolphin density was derived from Fulling et al. 
(2003), which describes the results of mammal surveys conducted in 
association with fall ichthyoplankton surveys from 1998 to 2001. The 
surveys were conducted by NMFS personnel from the U.S.-Mexico border to 
southern Florida, in water depths of 20 to 200 meters. Using the 
software program DISTANCE(copyright), density estimates were 
generated for East and West regions, with Mobile Bay as the dividing 
point. The East region is used in this document. Densities were 
provided for Atlantic spotted dolphins and unidentified T. truncatus/S. 
frontalis (among other species). The unidentified T. truncatus/S. 
frontalis category is treated as a separate species group with a unique 
density. Density estimates from Fulling et al. (2003) were not adjusted 
for sighting probability (perception bias) or surface availability 
(availability bias) [g(0) = 1] in the original survey report, likely 
resulting in underestimation of true density. Perception bias refers to 
the failure of observers to detect animals, although they are present 
in the survey area and available to be seen. Availability bias refers 
to animals that are in the survey area, but are not able to be seen 
because they are submerged when observers are present. Perception bias 
and availability bias result in the underestimation of abundance and 
density numbers (negative bias).
    Fulling et al. (2003) did not collect data to correct density for 
perception and availability bias. However, in order to address this 
negative bias, Eglin AFB has adjusted density estimates based on 
information provided in available literature. There are no published 
g(0) correction factors for Atlantic spotted dolphins. However, Barlow 
(2006) estimated g(0) for numerous marine mammal species near the 
Hawaiian Islands, including offshore pantropical spotted dolphins 
(Stenella attenuata). Separate estimates for this species were provided 
for group sizes of 1 to 20 animals [g(0) = 0.76], and greater than 20 
animals [g(0) = 1.00]. Although Fulling et al. (2003) sighted some 
spotted dolphin groups of more than 20 individuals, the 0.76 value is 
used as a more conservative approach. Barlow (2006) provides the 
following equation for calculating density:
[GRAPHIC] [TIFF OMITTED] TN04JN13.000


Where
n = number of animal group sightings on effort
S = mean group size
f(0) = sighting probability density at zero perpendicular distance 
(influenced by species detectability and sighting cues such as body 
size, blows, and number of animals in a group)
L = transect length completed (km)
g(0) = probability of seeing a group directly on a trackline 
(influenced by perception bias and availability bias)

    Because (n), (S), and (f0) cannot be directly 
incorporated as independent values due to lack of the original 
information, we substitute the variable Xspecies which 
incorporates all three values, such that Xspecies = 
(n)(S)(f0) for a given species. This changes the density 
equation to:
[GRAPHIC] [TIFF OMITTED] TN04JN13.001

    Using the minimum density estimates provided in Fulling et al. 
(2003) for Atlantic spotted dolphins and solving for 
XSpottedDolphin:
[GRAPHIC] [TIFF OMITTED] TN04JN13.002

XSpottedDolphin = 328.032.

    Placing this value of XSpottedDolphin and the revised 
g(0) estimate (0.76) in the original equation results in the following 
adjusted density estimate for Atlantic spotted dolphin:
[GRAPHIC] [TIFF OMITTED] TN04JN13.003

DAdjusted = 0.265

    Using the same method, adjusted density for the unidentified T. 
truncatus/S. frontalis species group is 0.009 animals/km\2\. There are 
no variances attached to either of these recalculated density values, 
so overall confidence in these values is unknown.

                Table 3--Marine Mammal Density Estimates
------------------------------------------------------------------------
                                                             Density
                        Species                          (animals/km\2\)
------------------------------------------------------------------------
Bottlenose dolphin \1\.................................            0.455
Atlantic spotted dolphin \2\...........................            0.265
Unidentified bottlenose dolphin/Atlantic spotted                   0.009
 dolphin \2\...........................................
------------------------------------------------------------------------
\1\ Source: Garrison, 2008; adjusted for observer and availability bias
  by the author.
\2\ Source: Fulling et al., 2003; adjusted for negative bias based on
  information provided by Barlow (2003; 2006)

Potential Effects of the Specified Activity on Marine Mammals

    Potential impacts from the detonation of explosives include non-
lethal injury (Level A harassment) and disturbance (Level B 
harassment). Takes in the form of mortality are neither anticipated nor 
requested. The number of marine mammals potentially impacted by 
Maritime Strike operations is based on impulsive noise and pressure 
waves generated by ordinance detonation at or near the water surface. 
Exposure to energy or pressure resulting from these detonations could 
result in injury or harassment of marine mammal species. The number of 
Maritime Strike missions generally corresponds to the number of live 
ordnance expenditures shown in Table 2. However, the number of bursts 
modeled for the CBU-103 cluster bomb is 202, which is the number of 
individual bomblets per bomb. Also, the 20 mm and 30 mm gunnery rounds 
were modeled as one burst each.
    Criteria and thresholds for estimating the exposures from a single 
explosive activity on marine mammals were established for the Seawolf 
Submarine Shock Test Final Environmental Impact Statement (FEIS) 
(``SEAWOLF'') and subsequently used in the USS WINSTON S. CHURCHILL 
(DDG 81) Ship Shock FEIS (``CHURCHILL'') (DoN,

[[Page 33362]]

1998 and 2001). We adopted these criteria and thresholds in a final 
rule on the unintentional taking of marine animals occurring incidental 
to the shock testing which involved large explosives (65 FR 77546; 
December 12, 2000). Because no large explosives (greater than 1000 lbs 
NEW) would be used by Eglin AFB during the specified activities, a 
revised acoustic criterion for small underwater explosions (i.e., 23 
pounds per square inch [psi] instead of previous acoustic criteria of 
12 psi for peak pressure over all exposures) has been established to 
predict onset of TTS.

Thresholds and Criteria for Injurious Physiological Impacts

Single Explosion

    For injury, NMFS uses dual criteria, eardrum rupture (i.e. 
tympanic-membrane injury) and onset of slight lung injury, to indicate 
the onset of injury. The threshold for tympanic-membrane (TM) rupture 
corresponds to a 50 percent rate of rupture (i.e., 50 percent of 
animals exposed to the level are expected to suffer TM rupture). This 
value is stated in terms of an Energy Flux Density Level (EL) value of 
1.17 inch pounds per square inch (in-lb/in2), approximately 205 dB re 1 
microPa\2\-sec.
    The threshold for onset of slight lung injury is calculated for a 
small animal (a dolphin calf weighing 26.9 lbs), and is given in terms 
of the ``Goertner modified positive impulse,'' indexed to 13 psi-msec 
(DoN, 2001). This threshold is conservative since the positive impulse 
needed to cause injury is proportional to animal mass, and therefore, 
larger animals require a higher impulse to cause the onset of injury. 
This analysis assumed the marine species populations were 100 percent 
small animals. The criterion with the largest potential impact range 
(most conservative), either TM rupture (energy threshold) or onset of 
slight lung injury (peak pressure), will be used in the analysis to 
determine Level A exposures for single explosive events.
    For mortality and serious injury, we use the criterion 
corresponding to the onset of extensive lung injury. This is 
conservative in that it corresponds to a 1 percent chance of mortal 
injury, and yet any animal experiencing onset severe lung injury is 
counted as a lethal exposure. For small animals, the threshold is given 
in terms of the Goertner modified positive impulse, indexed to 30.5 
psi-msec. Since the Goertner approach depends on propagation, source/
animal depths, and animal mass in a complex way, the actual impulse 
value corresponding to the 30.5 psi-msec index is a complicated 
calculation. To be conservative, the analysis used the mass of a calf 
dolphin (at 26.9 lbs) for 100 percent of the populations.

Multiple Explosions

    For multiple explosions, the CHURCHILL approach had to be extended 
to cover multiple sound events at the same training site. For multiple 
exposures, accumulated energy over the entire training time is the 
natural extension for energy thresholds since energy accumulates with 
each subsequent shot (detonation); this is consistent with the 
treatment of multiple arrivals in CHURCHILL. For positive impulse, it 
is consistent with the CHURCHILL final rule to use the maximum value 
over all impulses received.

Thresholds and Criteria for Non-Injurious Physiological Effects

    To determine the onset of TTS (non-injurious harassment)--a slight, 
recoverable loss of hearing sensitivity, there are dual criteria: an 
energy threshold and a peak pressure threshold. The criterion with the 
largest potential impact range (most conservative), either the energy 
or peak pressure threshold, will be used in the analysis to determine 
Level B TTS exposures. We refer the reader to the following sections 
for descriptions of the thresholds for each criterion.

Single Explosion--TTS-Energy Threshold

    The TTS energy threshold for explosives is derived from the Space 
and Naval Warfare Systems Center (SSC) pure-tone tests for TTS 
(Schlundt et al., 2000; Finneran and Schlundt, 2004). The pure-tone 
threshold (192 dB as the lowest value) is modified for explosives by 
(a) interpreting it as an energy metric, (b) reducing it by 10 dB to 
account for the time constant of the mammal ear, and (c) measuring the 
energy in 1/3-octave bands, the natural filter band of the ear. The 
resulting threshold is 182 dB re 1 microPa\2\-sec in any 1/3-octave 
band.

Single Explosion--TTS-Peak Pressure Threshold

    The second threshold applies to all species and is stated in terms 
of peak pressure at 23 psi (about 225 dB re 1 [mu]Pa). This criterion 
was adopted for Precision Strike Weapons (PSW) Testing and Training by 
Eglin Air Force Base in the Gulf of Mexico (NMFS, 2005). It is 
important to note that for small shots near the surface (such as in 
this analysis), the 23-psi peak pressure threshold generally will 
produce longer impact ranges than the 182-dB energy metric. 
Furthermore, it is not unusual for the TTS impact range for the 23-psi 
pressure metric to actually exceed the without-TTS (behavioral change 
without onset of TTS) impact range for the 177-dB energy metric.

Thresholds and Criteria for Behavioral Effects

Single Explosion

    For a single explosion, to be consistent with CHURCHILL, TTS is the 
criterion for Level B harassment. In other words, because behavioral 
disturbance for a single explosion is likely to be limited to a short-
lived startle reaction, use of the TTS criterion is considered 
sufficient protection and therefore behavioral effects (Level B 
behavioral harassment without onset of TTS) are not expected for single 
explosions.

Multiple Explosions--Without TTS

    For multiple explosions, the CHURCHILL approach had to be extended 
to cover multiple sound events at the same training site. For multiple 
exposures, accumulated energy over the entire uninterrupted firing time 
is the natural extension for energy thresholds since energy accumulates 
with each subsequent shot (detonation); this is consistent with the 
treatment of multiple arrivals in CHURCHILL. Because multiple 
explosions could occur within a discrete time period, a new acoustic 
criterion-behavioral disturbance without TTS is used to account for 
behavioral effects significant enough to be judged as harassment, but 
occurring at lower noise levels than those that may cause TTS.
    The threshold is based on test results published in Schlundt et al. 
(2000), with derivation following the approach of the CHURCHILL FEIS 
for the energy-based TTS threshold. The original Schlundt et al. (2000) 
data and the report of Finneran and Schlundt (2004) are the basis for 
thresholds for behavioral disturbance without TTS. During this study, 
instances of altered behavior sometimes began at lower exposures than 
those causing TTS; however, there were many instances when subjects 
exhibited no altered behavior at levels above the onset-TTS levels. 
Regardless of reactions at higher or lower levels, all instances of 
altered behavior were included in the statistical summary. The 
behavioral disturbance without TTS threshold for tones is derived from 
the SSC tests, and is found to be 5 dB below the threshold for TTS, or 
177 dB re 1

[[Page 33363]]

microPa\2\-sec maximum energy flux density level in any 1/3-octave band 
at frequencies above 100 Hz for cetaceans.

Summary of Thresholds and Criteria for Impulsive Sounds

    The effects, criteria, and thresholds used in the assessment for 
impulsive sounds are summarized in Table 4. The criteria for behavioral 
effects without physiological effects used in this analysis are based 
on use of multiple explosives from live, explosive firing during 
Maritime Strike exercises.

               Table 4--Current NMFS Acoustic Criteria When Addressing Harassment From Explosives
----------------------------------------------------------------------------------------------------------------
             Effect                   Criteria               Metric              Threshold           Effect
----------------------------------------------------------------------------------------------------------------
Mortality......................  Onset of Extensive  Goertner modified       indexed to 30.5    Mortality.
                                  Lung Injury.        positive impulse.       psi-msec
                                                                              (assumes 100
                                                                              percent small
                                                                              animal at 26.9
                                                                              lbs).
Injurious Physiological........  50 percent          Energy flux density...  1.17 in-lb/in\2\   Level A.
                                  Tympanic Membrane                           (about 205 dB re
                                  Rupture.                                    1 microPa\2\-
                                                                              sec).
Injurious Physiological........  Onset Slight Lung   Goertner modified       indexed to 13 psi- Level A.
                                  Injury.             positive impulse.       msec (assumes
                                                                              100 percent
                                                                              small animal at
                                                                              26.9 lbs).
Non-injurious Physiological....  TTS...............  Greatest energy flux    182 dB re 1        Level B.
                                                      density level in any    microPa\2\-sec.
                                                      \1/3\-octave band (>
                                                      100 Hz for toothed
                                                      whales and > 10 Hz
                                                      for baleen whales)--
                                                      for total energy over
                                                      all exposures.
Non-injurious Physiological....  TTS...............  Peak pressure over all  23 psi...........  Level B.
                                                      exposures.
Non-injurious Behavioral.......  Multiple            Greatest energy flux    177 dB re 1        Level B.
                                  Explosions          density level in any    microPa\2\-sec.
                                  Without TTS.        \1/3\-octave (> 100
                                                      Hz for toothed whales
                                                      and > 10 Hz for
                                                      baleen whales)--for
                                                      total energy over all
                                                      exposures (multiple
                                                      explosions only).
----------------------------------------------------------------------------------------------------------------

Anticipated Effects on Habitat

    The primary source of marine mammal habitat impact is noise 
resulting from live Maritime Strike missions. However, the noise does 
not constitute a long-term physical alteration of the water column or 
bottom topography. In addition, the activity is not expected to affect 
prey availability, is of limited duration, and is intermittent in time. 
Surface vessels associated with the missions are present in limited 
duration and are intermittent as well. Therefore, it is not anticipated 
that marine mammal utilization of the waters in the project area will 
be affected, either temporarily or permanently, as a result of mission 
activities.
    Other sources that could potentially impact marine mammal habitat 
were considered and include the introduction of fuel, debris, ordnance, 
and chemical materials into the water column. The potential effects of 
each were analyzed in the Draft Environmental Assessment and determined 
to be insignificant. The analyses are summarized in the following 
paragraphs (for a complete discussion of potential effects, please 
refer to section 3.3 in the DEA).
    Metals typically used to construct bombs, missiles, and gunnery 
rounds include copper, aluminum, steel, and lead, among others. 
Aluminum is also present in some explosive materials. These materials 
would settle to the seafloor after munitions detonate. Metal ions would 
slowly leach into the substrate and the water column, causing elevated 
concentrations in a small area around the munitions fragments. Some of 
the metals, such as aluminum, occur naturally in the ocean at varying 
concentrations and would not necessarily impact the substrate or water 
column. Other metals, such as lead, could cause toxicity in microbial 
communities in the substrate. However, such effects would be localized 
to a very small distance around munitions fragments and would not 
significantly affect the overall habitat quality of sediments in the 
northeastern GOM. In addition, metal fragments would corrode, degrade, 
and become encrusted over time.
    Chemical materials include explosive byproducts and also fuel, oil, 
and other fluids associated with remotely controlled target boats. 
Explosive byproducts would be introduced into the water column through 
detonation of live munitions. Explosive materials would include 2,4,6-
trinitrotoluene (TNT) and RDX, among others. Various byproducts are 
produced during and immediately after detonation of TNT and RDX. During 
the very brief time that a detonation is in progress, intermediate 
products may include carbon ions, nitrogen ions, oxygen ions, water, 
hydrogen cyanide, carbon monoxide, nitrogen gas, nitrous oxide, cyanic 
acid, and carbon dioxide (Becker, 1995). However, reactions quickly 
occur between the intermediates, and the final products consist mainly 
of water, carbon monoxide, carbon dioxide, and nitrogen gas, although 
small amounts of other compounds are typically produced as well.
    Chemicals introduced into the water column would be quickly 
dispersed by waves, currents, and tidal action, and eventually become 
uniformly distributed. A portion of the carbon compounds such as carbon 
monoxide and carbon dioxide would likely become integrated into the 
carbonate system (alkalinity and pH buffering capacity of seawater). 
Some of the nitrogen and carbon compounds, including petroleum 
products, would be metabolized or assimilated by phytoplankton and 
bacteria. Most of the gas products that do not react with the water or 
become assimilated by organisms would be released into the atmosphere. 
Due to dilution, mixing, and transformation, none of these chemicals 
are expected to have significant impacts on the marine environment.
    Explosive material that is not consumed in a detonation could sink 
to the substrate and bind to sediments. However, the quantity of such 
materials is expected to be inconsequential. Research has shown that if 
munitions function properly, nearly full combustion of the explosive 
materials will occur, and only extremely small amounts of raw material 
will remain. In

[[Page 33364]]

addition, any remaining materials would be naturally degraded. TNT 
decomposes when exposed to sunlight (ultraviolet radiation), and is 
also degraded by microbial activity (Becker, 1995). Several types of 
microorganisms have been shown to metabolize TNT. Similarly, RDX 
decomposes by hydrolysis, ultraviolet radiation exposure, and 
biodegradation.
    Based on this information, the proposed Maritime Strike activities 
would not have any impact on the food or feeding success of marine 
mammals in the northern GOM. Additionally, no loss or modification of 
the habitat used by cetaceans in the GOM is expected. Marine mammals 
are anticipated to temporarily vacate the area of live fire events. 
However, these events usually do not last more than 90 to 120 min at a 
time, and animals are anticipated to return to the activity area during 
periods of non-activity. Thus, the proposed activity is not expected to 
have any habitat-related effects that could cause significant or long-
term consequences for individual marine mammals or on the food sources 
that they utilize.

Proposed Mitigation

    In order to issue an incidental take authorization (ITA) under 
sections 101(a)(5)(A) and (D) of the MMPA, NMFS must, where applicable, 
set forth the permissible methods of taking pursuant to such activity 
and other means of effecting the least practicable impact on such 
species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses (where relevant). The NDAA of 2004 amended the MMPA as 
it relates to military readiness activities and the ITA process such 
that ``least practicable impact'' shall include consideration of 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the ``military readiness activity''. The Maritime 
Strike activities described in Eglin AFB's application are considered 
military readiness activities.

Visual Mitigation

    Areas to be used for Maritime Strike operations would be visually 
monitored for marine mammal presence from several platforms before, 
during, and after the commencement of the mission. Eglin AFB would 
provide experienced protected species survey personnel, vessels, and 
equipment as required for vessel-based surveys. The primary observers 
would be marine scientists with over 1,000 hours of marine mammal 
surveying experience collectively. Additionally, all range clearance 
personnel involved with the missions would receive NMFS-approved 
training developed by the Eglin Natural Resources Section. The 
designated protected species survey vessels would be two 25-ft (7.6 m) 
Parker 2520 boats with a fully enclosed pilothouse and tower. These 
vessels provide large viewing areas and observers would be stationed 
approximately 16-ft (4.9 m) above the water surface. Each vessel will 
have two observers and each observer will be equipped with binoculars. 
Observers will rotate on a regular basis to prevent eye fatigue as 
needed. Additional protected species survey vessels can be made 
available if required.
    If the presence of one or more marine mammals is detected, the 
target area will be avoided. In addition, monitoring will continue 
during the mission. If marine mammals are detected at any time, the 
mission will halt immediately and relocate as necessary or be suspended 
until the marine mammal has left the area. The visual mitigation 
procedures for Maritime Strike operations are outlined below.
    Pre-mission: The purposes of pre-mission monitoring are to: (1) 
Evaluate the test site for environmental suitability of the mission; 
and (2) verify that the Zone of Influence (ZOI) is free of visually 
detectable marine mammals, as well as potential indicators of these 
species. The area of the ZOI surveyed would be based on the distance to 
the largest Level B harassment threshold for the specific ordnance 
involved in a given test. For example, the largest ZOI would be 3,526 m 
(2.2 mi), which corresponds to the distance to the Level B threshold 
(177 dB) for 945 lb munitions detonated at 3 m (10 ft) underwater. The 
smallest ZOI would be 37 m (0.02 mi), which is the distance to the 
Level B threshold (23 psi) for 20 mm gunnery rounds. Table 5 provides 
the ZOI ranges for all the ordnance types and detonation depths 
proposed for Maritime Strike operations. On the morning of the Maritime 
Strike mission, the test director and safety officer would confirm that 
there are no issues that would preclude mission execution and that 
weather is adequate to support mitigation measures.
(A) Two Hours Prior to Mission
    Mission-related surface vessels would be on site at least two hours 
prior to the mission. Observers on board at least one vessel would 
assess the overall suitability of the test site based on environmental 
conditions (e.g., sea state) and presence/absence of marine mammals or 
marine mammal indicators. This information would be related to the 
safety officer.
(B) One and One-half Hours Prior to Mission
    Vessel-based surveys and video camera surveillance would begin one 
and one-half hours prior to live weapon deployment. Surface vessel 
observers would survey the applicable ZOI and relay all marine species 
and indicator sightings, including the time of sighting and direction 
of travel, if known, to the safety officer. Surveys would continue for 
approximately one hour. During this time, mission personnel in the test 
area would also observe for marine species as feasible. If marine 
mammals or indicators are observed within the applicable ZOI, the test 
range would be declared ``fouled,'' which would signify to mission 
personnel that conditions are such that a live ordnance drop cannot 
occur (e.g., protected species or civilian vessels are in the test 
area). If no marine mammals or indicators are observed, the range will 
be declared ``green.''
(C) One-half Hour Prior to Mission
    At approximately 30 minutes prior to live weapon deployment, marine 
species observers would be instructed to leave the test site and remain 
outside the safety zone, which on average would be 9.5 miles from the 
detonation point, (the actual size would be determined by weapon NEW 
and method of delivery) during conduct of the mission. Once the survey 
vessels have arrived at the perimeter of the safety zone (approximately 
30 minutes after being instructed to leave, depending on actual travel 
time) the mission would be allowed to proceed. Monitoring for protected 
species would continue from the periphery of the safety zone while the 
mission is in progress. The other safety boat crews would also be 
instructed to observe for marine mammals. Due to the distance from the 
target site, these observations would be considered supplemental and 
would not be relied upon as the primary monitoring method. After survey 
vessels leave the area, marine species monitoring would continue from 
the tower through the video feed received from the high definition 
cameras on the instrument barge.
(D) Execution of Mission
    Immediately prior to live weapons drop, the test director and 
safety officer would communicate to confirm the results of marine 
mammal surveys and the appropriateness of proceeding with the mission. 
The safety officer would have final authority to proceed with, 
postpone, move, or cancel the mission.

[[Page 33365]]

The mission would be postponed or moved if:
    (1) Any marine mammal is visually detected within the applicable 
ZOI. Postponement would continue until the animal(s) that caused the 
postponement is confirmed to be outside of the applicable ZOI due to 
the animal swimming out of the range.
    (2) Large schools of fish or large flocks of birds feeding at the 
surface are observed within the applicable ZOI. Postponement would 
continue until these potential indicators are confirmed to be outside 
the applicable ZOI.
    In the event of a postponement, pre-mission monitoring would 
continue as long as weather and daylight hours allow.
    Post-mission Monitoring: Post mission monitoring would be designed 
to determine the effectiveness of pre-mission visual mitigation by 
reporting sightings of any dead or injured marine mammals. If post-
mission surveys determine that an injury or lethal take of a marine 
mammal has occurred, the next Maritime Strike mission would be 
suspended until the test procedure and the monitoring methods would be 
reviewed with NMFS and appropriate changes made. Post-mission 
monitoring surveys would be conducted by the same observers that 
conducted pre-mission surveys, and would commence as soon as EOD 
personnel declare the test area safe. Vessels would move into the 
applicable ZOI from outside the safety zone and monitor for at least 30 
minutes, concentrating on the area down-current of the test site. The 
monitoring team would document any marine mammals that were killed or 
injured as a result of the test and immediately contact the local 
marine mammal stranding network and NMFS to coordinate recovery and 
examination of any dead animals. The species, number, location, and 
behavior of any animals observed would be documented and reported to 
the Eglin Natural Resources Section.
    Multiple offshore Air Force missions have been successfully 
executed in the general vicinity of the proposed Maritime Strike test 
location (W-151 of the EGTTR). These missions have involved both inert 
(no explosives) and live weapons testing, and include the following:
     2009 Stand-off Precision Guided Munitions (SOPGM) live 
missile tests.
     2012 Maritime Strike inert drops.
     2013 Longbow live missile test (in-air detonation).
     2013 Combat Hammer Maritime WESP missions (inert drops in 
the Gulf and strafing in the Choctawhatchee Bay).
    During these missions, vessel-based observers surveyed for 
protected marine species (marine mammals and sea turtles) and species 
indicators. They also provided support to enforce human safety 
exclusion zones.
    All live and inert missions were conducted in a variety of sea 
states and weather conditions that encompass the environmental 
conditions likely to be encountered during Maritime Strike activities. 
While no marine mammals were sighted within the various take threshold 
zones (mortality, Level A and B harassment zones) during any of the 
live tests (i.e., SOPGM and Longbow missile), survey personnel judged 
that they were able to adequately observe the sea surface and there was 
reasonable likelihood that marine mammals would have been detected if 
present. There have been no documented marine mammal takes throughout 
Eglin's history of activities in the Gulf of Mexico. Therefore, based 
on these factors, Eglin AFB and NMFS expect that trained protected 
species observers would be able to adequately survey and clear 
mortality zones (maximum of 457 m) and effectively communicate any 
marine mammal sightings to test directors. Further, we expect that test 
directors would be able to act quickly to delay live weapon drops 
should protected species be observed.
    NMFS has carefully evaluated the applicant's proposed mitigation 
measures and considered a range of other measures in the context of 
ensuring that NMFS prescribes the means of effecting the least 
practicable impact on the affected marine mammal species and stocks and 
their habitat. Our evaluation of potential measures included 
consideration of the following factors in relation to one another:
     The manner in which, and the degree to which, the 
successful implementation of the measure is expected to minimize 
adverse impacts to marine mammals;
     The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
     The practicability of the measure for applicant 
implementation, including consideration of personnel safety, 
practicability of implementation, and impact on the effectiveness of 
the military-readiness activity.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, the proposed mitigation 
measures provide the means of effecting the least practicable impact on 
marine mammal species or stocks and their habitat, paying particular 
attention to rookeries, mating grounds, and areas of similar 
significance, while also considering personnel safety, practicability 
of implementation, and impact on the effectiveness of the military-
readiness activity.

Proposed Monitoring and Reporting

    In order to issue an ITA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must, where applicable, set forth 
``requirements pertaining to the monitoring and reporting of such 
taking''. The MMPA implementing regulations at 50 CFR 216.104(a)(13) 
indicate that requests for ITAs must include the suggested means of 
accomplishing the necessary monitoring and reporting that will result 
in increased knowledge of the species and of the level of taking or 
impacts on populations of marine mammals that are expected to be 
present in the proposed action area.
    NMFS proposes to include the following measures in the Maritime 
Strike IHA (if issued). They are:
    (1) Eglin will track their use of the EGTTR for test firing 
missions and protected species observations, through the use of mission 
reporting forms.
    (2) A summary annual report of marine mammal observations and 
Maritime Strike activities will be submitted to the NMFS Southeast 
Regional Office (SERO) and the Office of Protected Resources either at 
the time of a request for renewal of an IHA or 90 days after expiration 
of the current IHA if a new IHA is not requested. This annual report 
must include the following information: (i) Date and time of each 
Maritime Strike exercise; (ii) a complete description of the pre-
exercise and post-exercise activities related to mitigating and 
monitoring the effects of Maritime Strike exercises on marine mammal 
populations; and (iii) results of the Maritime Strike exercise 
monitoring, including numbers by species/stock of any marine mammals 
noted injured or killed as a result of the missions and number of 
marine mammals (by species if possible) that may have been harassed due 
to presence within the activity zone.
    (3) If any dead or injured marine mammals are observed or detected 
prior to testing, or injured or killed during live fire, a report must 
be made to NMFS by the following business day.
    (4) Any unauthorized takes of marine mammals (i.e., injury or 
mortality) must be immediately reported to NMFS and to the respective 
stranding network representative.

[[Page 33366]]

Estimated Take by Incidental Harassment

    As it applies to a ``military readiness activity'', the definition 
of harassment is (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].
    Takes by Level A and B harassment are anticipated as a result of 
the Maritime Strike mission activities. The exercises are expected to 
only affect animals at or very near the surface of the water. Cetaceans 
in the vicinity of the exercises may incur temporary changes in 
behavior, and/or temporary changes in their hearing thresholds. Based 
on the proposed mitigation and monitoring measures described earlier in 
this document, no serious injury or mortality of marine mammals is 
anticipated as a result of Maritime Strike activities, and no takes by 
serious injury or mortality are proposed to be authorized.
    Estimating the impacts to marine mammals from underwater 
detonations is difficult due to complexities of the physics of 
explosive sound under water and the limited understanding with respect 
to hearing in marine mammals. Assessments of impacts from Maritime 
Strike exercises use, and improve upon, the criteria and thresholds for 
marine mammal impacts that were developed for the shock trials of the 
USS SEAWOLF and the USS WINSTON S. CHURCHILL (DDG-81) (Navy, 1998; 
2001). The criteria and thresholds used in those actions were adopted 
by NMFS for use in calculating incidental takes from explosives. 
Criteria for assessing impacts from Eglin AFB's Maritime Strike 
exercises include: (1) Mortality, as determined by exposure to a 
certain level of positive impulse pressure (expressed as pounds per 
square inch per millisecond or psi-msec); (2) injury, both hearing-
related and non-hearing related; and (3) harassment, as determined by a 
temporary loss of some hearing ability and behavioral reactions. Due to 
the mitigation measures proposed by NMFS for implementation, mortality 
resulting from the resulting sounds generated into the water column 
from detonations was determined to be highly unlikely and was not 
considered further by Eglin AFB or NMFS.
    Permanent hearing loss is considered an injury and is termed 
permanent threshold shift (PTS). NMFS, therefore, categorizes PTS as 
Level A harassment. Temporary loss of hearing ability is termed TTS, 
meaning a temporary reduction of hearing sensitivity which abates 
following noise exposure. TTS is considered non-injurious and is 
categorized as Level B harassment. NMFS recognizes dual criteria for 
TTS, one based on peak pressure and one based on the greatest \1/3\ 
octave sound exposure level (SEL) or energy flux density level (EFDL), 
with the more conservative (i.e., larger) of the two criteria being 
selected for impacts analysis (note: SEL and EFDL are used 
interchangeably, but with increasing scientific preference for SEL). 
The peak pressure metric used to predict TTS is 23 pounds per square 
inch (psi).
    Documented behavioral reactions occur at noise levels below those 
considered to cause TTS in marine mammals (Finneran et al., 2002; 
Schlundt et al., 2000; Finneran and Schlundt, 2004). In controlled 
experimental situations, behavioral effects are typically defined as 
alterations of trained behaviors. Behavioral effects in wild animals 
are more difficult to define but may include decreased ability to feed, 
communicate, migrate, or reproduce. Abandonment of an area due to 
repeated noise exposure is also considered a behavioral effect. 
Analyses in other sections of this document refer to such behavioral 
effects as ``sub-TTS Level B harassment.'' Schlundt et al. (2000) 
exposed bottlenose dolphins and beluga whales to various pure-tone 
sound frequencies and intensities in order to measure underwater 
hearing thresholds. Masking is considered to have occurred because of 
the ambient noise environment in which the experiments took place. 
Sound levels were progressively increased until behavioral alterations 
were noted (at which point the onset of TTS was presumed). It was found 
that decreasing the sound intensity by 4 to 6 dB greatly decreased the 
occurrence of anomalous behaviors. The lowest sound pressure levels, 
over all frequencies, at which altered behaviors were observed, ranged 
from 178 to 193 dB re 1 [micro]Pa for the bottlenose dolphins and from 
180 to 196 dB re 1 [micro]Pa for the beluga whales. Thus, it is 
reasonable to consider that sub-TTS (behavioral) effects occur at 
approximately 6 dB below the TTS-inducing sound level, or at 
approximately 177 dB in the greatest \1/3\ octave band EFDL/SEL.
    Table 4 (earlier in this document) summarizes the relevant 
thresholds for levels of noise that may result in Level A harassment 
(injury) or Level B harassment via TTS or behavioral disturbance to 
marine mammals. Mortality and injury thresholds are designed to be 
conservative by considering the impacts that would occur to the most 
sensitive life stage (e.g., a dolphin calf).
    The following three factors were used to estimate the potential 
noise effects on marine mammals from Maritime Strike operations: (1) 
The zone of influence, which is the distance from the explosion to 
which a particular energy or pressure threshold extends; (2) the 
density of animals potentially occurring within the zone of influence; 
and (3) the number of events.
    The zone of influence is defined as the area or volume of ocean in 
which marine mammals could potentially be exposed to various noise 
thresholds associated with exploding ordnance. Table 5 provides the 
estimated ZOI radii for the Maritime Strike ordnance. At this time, 
there are no empirical data or information that would allow NMFS to 
establish a peak pressure criterion for sub-TTS behavioral disruption.

                              Table 5--Estimated Range for a Zone of Impact (ZOI) Distance for the Maritime Strike Ordnance
                                                                       [In meters]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                             Mortality      Level A Harassment               Level B Harassment
                                                                           -----------------------------------------------------------------------------
                  Munition                     Height/Depth of detonation    30.5 psi-
                                                                                msec     205 dB EFD*  13 psi-msec  182 dB EFD*     23 psi    177 dB EFD*
--------------------------------------------------------------------------------------------------------------------------------------------------------
GBU-10.....................................  Water Surface................          202          275          362         1023         1280         1361
GBU-24.....................................  Water Surface................          202          275          362         1023         1280         1361
GBU-31 (JDAM)..............................  Water Surface................          202          275          362         1023         1280         1361
                                             20 feet AGL..................            0            0            0            0            0            0

[[Page 33367]]

 
                                             5 feet underwater............          385          468          700         2084         1281         2775
                                             10 feet underwater...........          457          591          836         2428         1280         3526
GBU-12.....................................  Water Surface................          114          161          243          744          752         1020
GBU-38 (JDAM)..............................  Water Surface................          114          161          243          744          752         1020
                                             20 feet AGL..................            0            0            0            0            0            0
                                             5 feet underwater............          239          280          445         1411          752         2070
                                             10 feet underwater...........          279          345          532         1545          752         2336
GBU-54 (LJDAM).............................  Water Surface................          114          161          243          744          752         1020
AGM-65E/L/K/G2 (Maverick)..................  Water Surface................           84          124          187          618          575          846
CBU-103....................................  Water Surface................            9          231           21          947          111         1335
AGM-114 (Hellfire).........................  Water Surface................           46           70          105          425          353          618
M-117......................................  20 feet AGL..................            0            0            0            0            0            0
                                             Water Surface................          147          203          293          847          950         1125
PGU-13 HEI 30 mm...........................  Water Surface................            0            6            7           31           60           55
M56/PGU-28 HEI 20 mm.......................  Water Surface................            0            0            0           16           37           27
--------------------------------------------------------------------------------------------------------------------------------------------------------
* In greatest \1/3\ octave band above 10 Hz or 100 Hz.

    Density estimates for marine mammals occurring in the EGTTR are 
provided in Table 3. As discussed above, densities were derived from 
the results of published documents authored by NMFS personnel. Density 
is nearly always reported for an area (e.g., animals per square 
kilometer). Analyses of survey results may include correction factors 
for negative bias, such as the Garrison (2008) report for bottlenose 
dolphins. Even though Fulling et al. (2003) did not provide a 
correction for Atlantic spotted dolphins or unidentified bottlenose/
spotted dolphins, Eglin AFB adjusted those densities based on 
information provided in other published literature (Barlow 2003; 2006). 
Although the study area appears to represent only the surface of the 
water (two-dimensional), density actually implicitly includes animals 
anywhere within the water column under that surface area. Density 
estimates usually assume that animals are uniformly distributed within 
the prescribed area, even though this is likely rarely true. Marine 
mammals are often clumped in areas of greater importance, for example, 
in areas of high productivity, lower predation, safe calving, etc. 
Density can occasionally be calculated for smaller areas, but usually 
there are insufficient data to calculate density for such areas. 
Therefore, assuming an even distribution within the prescribed area is 
the typical approach.
    In addition, assuming that marine mammals are distributed evenly 
within the water column does not accurately reflect behavior. Databases 
of behavioral and physiological parameters obtained through tagging and 
other technologies have demonstrated that marine animals use the water 
column in various ways. Some species conduct regular deep dives while 
others engage in much shallower dives, regardless of bottom depth. 
Assuming that all species are evenly distributed from surface to bottom 
is almost never appropriate and can present a distorted view of marine 
mammal distribution in any region. Therefore, a depth distribution 
adjustment is applied to marine mammal densities in this document 
(Table 6). By combining marine mammal density with depth distribution 
information, a three-dimensional density estimate is possible. These 
estimates allow more accurate modeling of potential marine mammal 
exposures from specific noise sources.

                 Table 6--Depth Distribution of Marine Mammals in the Maritime Strike Test Area
----------------------------------------------------------------------------------------------------------------
                Species                       Depth distribution                        Reference
----------------------------------------------------------------------------------------------------------------
Bottlenose dolphin....................  Daytime: 96% at <50 m, 4% at    Klatsky et al. (2007).
                                         >50 m; Nightime: 51% at <50
                                         m, 8% at 50-100 m, 19% at 101-
                                         250 m, 13% at 251-450 m, and
                                         9% at >450 m.
Atlantic spotted dolphin..............  76% at <10 m, 20% at 10-20 m,   Davis et al. (1996).
                                         and 4% at 21-60 m.
----------------------------------------------------------------------------------------------------------------

    As mentioned previously, the number of Maritime Strike activities 
generally corresponds to the number of live ordnance expenditures, as 
shown in Table 2. However, the number of bursts modeled for the CBU-103 
cluster bomb is 202, which is the number of individual bomblets per 
bomb. Also, the 20 mm and 30 mm gunnery rounds were modeled as one 
burst each.
    Table 7 indicates the modeled potential for lethality, injury, and 
non-injurious harassment (including behavioral harassment) to marine 
mammals in the absence of mitigation measures. The numbers represent 
total impacts for all detonations combined. Mortality was calculated as 
approximately one-half an animal for bottlenose dolphins and about 0.1 
animals for spotted dolphins. It is expected that, with implementation 
of the management practices described below, potential impacts would be 
mitigated to the point that there would be no mortality takes. Based on 
the low mortality exposure estimates calculated

[[Page 33368]]

by the acoustic model combined with the implementation of mitigation 
measures, zero marine mammals are expected to be affected by pressure 
levels associated with mortality. Therefore, Eglin AFB has requested an 
IHA, as opposed to an LOA.

           Table 7--Modeled Number of Marine Mammals Potentially Affected by Maritime Strike Missions
----------------------------------------------------------------------------------------------------------------
                                                                                      Level B         Level B
                     Species                         Mortality        Level A       Harassment      Harassment
                                                                    Harassment         (TTS)       (Behavioral)
----------------------------------------------------------------------------------------------------------------
Bottlenose dolphin..............................           0.524           2.008          30.187          61.069
Atlantic spotted dolphin........................           0.145           1.050          16.565          31.345
Unidentified bottlenose dolphin/Atlantic spotted           0.010           0.040           0.597           1.208
 dolphin........................................
                                                 ---------------------------------------------------------------
    TOTAL.......................................           0.679           3.098          47.349          93.622
----------------------------------------------------------------------------------------------------------------

    Table 8 provides Eglin AFB's the annual number of marine mammals, 
by species, potentially taken by Level A harassment and Level B 
harassment, by Maritime Strike operations. It should be noted that 
these estimates are derived without consideration of the effectiveness 
of Eglin AFB's proposed mitigation measures. As indicated in Table 8, 
Eglin AFB and NMFS estimate that approximately three marine mammals 
could potentially be exposed to injurious Level A harassment noise 
levels (205 dB re 1 [mu]Pa\2\-s or higher).

                                     Table 8--Number of Marine Mammals Takes
----------------------------------------------------------------------------------------------------------------
                                                                                      Level B         Level B
                             Species                                  Level A       Harassment      Harassment
                                                                    Harassment         (TTS)       (Behavioral)
----------------------------------------------------------------------------------------------------------------
Bottlenose dolphin..............................................               2              30              61
Atlantic spotted dolphin........................................               1              16              32
Unidentified bottlenose dolphin/Atlantic spotted dolphin........               0               1               1
                                                                 -----------------------------------------------
    TOTAL.......................................................               3              47              93
----------------------------------------------------------------------------------------------------------------

    Approximately 47 marine mammals would be exposed annually to non-
injurious (TTS) Level B harassment associated with the 182 dB re 1 
[mu]Pa\2\-s threshold. TTS results from fatigue or damage to hair cells 
or supporting structures and may cause disruption in the processing of 
acoustic cues; however, hearing sensitivity is recovered within a 
relatively short time. Based on Eglin AFB and NMFS' estimates, up to 94 
marine mammals may experience a behavioral response to these exercises 
associated with the 177 dB re 1 [mu]Pa\2\-s threshold (see Table 8). 
NMFS has preliminarily determined that this number will be 
significantly lower due to the expected effectiveness of the mitigation 
measures proposed for inclusion in the IHA (if issued).

Negligible Impact and Preliminary Determinations

    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.'' In making a negligible impact determination, 
NMFS considers a variety of factors, including but not limited to: (1) 
The number of anticipated mortalities; (2) the number and nature of 
anticipated injuries; (3) the number, nature, and intensity, and 
duration of harassment; and (4) the context in which the takes occur.
    The takes from Level B harassment will be due to potential 
behavioral disturbance and TTS. The takes from Level A harassment will 
be due to potential tympanic-membrane (TM) rupture. Activities would 
only occur over a timeframe of two to three weeks in June 2013, with 
one or two missions occurring per day. It is possible that some 
individuals may be taken more than once if those individuals are 
located in the exercise area on two different days when exercises are 
occurring. However, multiple exposures are not anticipated to have 
effects beyond Level A and Level B harassment.
    While animals may be impacted in the immediate vicinity of the 
activity, because of the small ZOIs (compared to the vast size of the 
GOM ecosystem where these species live) and the short duration of the 
Maritime Strike operations, NMFS has preliminarily determined that 
there will not be a substantial impact on marine mammals or on the 
normal functioning of the nearshore or offshore GOM ecosystems. The 
proposed activity is not expected to impact rates of recruitment or 
survival of marine mammals since neither mortality (which would remove 
individuals from the population) nor serious injury are anticipated to 
occur. In addition, the proposed activity would not occur in areas 
(and/or times) of significance for the marine mammal populations 
potentially affected by the exercises (e.g., feeding or resting areas, 
reproductive areas), and the activities would only occur in a small 
part of their overall range, so the impact of any potential temporary 
displacement would be negligible and animals would be expected to 
return to the area after the cessations of activities. Although the 
proposed activity could result in Level A (TM rupture) and Level B 
(behavioral disturbance and TTS) harassment of marine mammals, the 
level of harassment is not anticipated to impact rates of recruitment 
or survival of marine mammals because the number of exposed animals is 
expected to be low due to the short term and site specific nature of 
the activity, and the type of effect would not be detrimental to rates 
of recruitment and survival.
    Additionally, the mitigation and monitoring measures proposed to be 
implemented (described earlier in this document) are expected to 
further minimize the potential for harassment.

[[Page 33369]]

The protected species surveys would require Eglin AFB to search the 
area for marine mammals, and if any are found in the live fire area, 
then the exercise would be suspended until the animal(s) has left the 
area or relocated. Moreover, marine species observers located in the 
Eglin control tower would monitor the high-definition video feed from 
cameras located on the instrument barge anchored on-site for the 
presence of protected species. Furthermore, Maritime Strike missions 
would be delayed or rescheduled if the sea state is greater than a 4 on 
the Beaufort Scale at the time of the test. In addition, Maritime 
Strike missions would occur no earlier than two hours after sunrise and 
no later than two hours prior to sunset to ensure adequate daylight for 
pre- and post-mission monitoring.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the mitigation and monitoring 
measures, NMFS preliminarily finds that Eglin AFB's Maritime Strike 
operations will result in the incidental take of marine mammals, by 
Level A and Level B harassment only, and that the taking from the 
Maritime Strike exercises will have a negligible impact on the affected 
species or stocks.

Impact on Availability of Affected Species or Stock for Taking for 
Subsistence Uses

    There are no relevant subsistence uses of marine mammals implicated 
by this action. Therefore, NMFS has preliminarily determined that the 
total taking of affected species or stocks would not have an 
unmitigable adverse impact on the availability of such species or 
stocks for taking for subsistence purposes.

Endangered Species Act (ESA)

    Eglin AFB initiated consultation with the Southeast Region, NMFS, 
under section 7 of the ESA regarding the effects of this action on ESA-
listed species and critical habitat under the jurisdiction of NMFS. The 
consultation will be completed and a biological opinion issued prior to 
any final determinations on the IHA. Due to the location of the 
activity, no ESA-listed marine mammal species are likely to be 
affected; therefore, NMFS has preliminarily determined that this 
proposed IHA would have no effect on ESA-listed species. However, prior 
to issuance of this IHA, NMFS will make a final determination whether 
additional consultation is necessary.

National Environmental Policy Act (NEPA)

    Eglin AFB released a Draft Environmental Assessment (EA) on the 
Maritime Strike Operations. NMFS has made this EA available on the 
permits Web page. Eglin AFB will issue a Final EA and a Finding of No 
Significant Impact (FONSI) on the Maritime Strike Operations prior to 
NMFS' final determination on the IHA.
    In accordance with NOAA Administrative Order 216-6 (Environmental 
Review Procedures for Implementing the National Environmental Policy 
Act, May 20, 1999), NMFS will review the information contained in Eglin 
AFB's EA and determine whether the EA accurately and completely 
describes the preferred action alternative, a reasonable range of 
alternatives, and the potential impacts on marine mammals, endangered 
species, and other marine life that could be impacted by the preferred 
and non-preferred alternatives. Based on this review and analysis, NMFS 
may adopt Eglin AFB's PEA under 40 CFR 1506.3, and issue its own FONSI 
statement on issuance of an annual authorization under section 
101(a)(5) of the MMPA.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
authorize the take of two species of marine mammals incidental to Eglin 
AFB's Maritime Strike operations in the GOM provided the previously 
mentioned mitigation, monitoring, and reporting requirements are 
incorporated.

    Dated: May 29, 2013.
Helen M. Golde,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2013-13119 Filed 6-3-13; 8:45 am]
BILLING CODE 3510-22-P