[Federal Register Volume 78, Number 22 (Friday, February 1, 2013)]
[Notices]
[Pages 7402-7411]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-02195]
-----------------------------------------------------------------------
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XC430
Small Takes of Marine Mammals Incidental to Specified Activities;
Cape Wind's High Resolution Survey in Nantucket Sound, MA
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments.
-----------------------------------------------------------------------
SUMMARY: NMFS has received an application from Cape Wind Associates
(CWA) for an Incidental Harassment Authorization (IHA) to take marine
mammals, by harassment, incidental to pre-construction high resolution
survey activities. CWA began pre-construction activities last year, but
was unable to complete the entire survey. Pursuant to the Marine Mammal
Protection Act (MMPA), NMFS is requesting comments on its proposal to
issue a second IHA to CWA to incidentally take, by Level B harassment
only, marine mammals during the specified activity.
DATES: Comments and information must be received no later than March 4,
2013.
ADDRESSES: Comments on the application and this proposal 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 20910-3225. The mailbox address
for providing email comments is ITP.Magliocca@noaa.gov. 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.
A copy of the application containing a list of the references used
in this document may be obtained by visiting the internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm. The following associated
documents are also
[[Page 7403]]
available at the same internet address: 2011 Environmental Assessment.
Documents cited in this notice may also be viewed, by appointment,
during regular business hours, at the aforementioned address.
FOR FURTHER INFORMATION CONTACT: Michelle Magliocca, 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 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 specific 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 a 1-year authorization to
incidentally take small numbers of marine mammals by harassment,
provided that there is no potential for serious injury or mortality to
result from the activity. 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.
Except with respect to certain activities not pertinent here, the
MMPA defines ``harassment'' as: Any act of pursuit, torment, or
annoyance which (i) has the potential to injure a marine mammal or
marine mammal stock in the wild [Level A harassment]; or (ii) has the
potential to disturb a marine mammal or marine mammal stock in the wild
by causing disruption of behavioral patterns, including, but not
limited to, migration, breathing, nursing, breeding, feeding, or
sheltering [Level B harassment].
Summary of Request
On December 19, 2012, NMFS received an application from CWA for the
taking of marine mammals incidental to high resolution survey
activities. NMFS determined that the application was adequate and
complete on December 31, 2012.
CWA proposes to conduct a high resolution geophysical survey in
Nantucket Sound, Massachusetts. The proposed activity would occur
during daylight hours over an estimated 109-day period beginning in
April 2013. The following equipment used during the survey is likely to
result in the take of marine mammals: Shallow-penetration subbottom
profiler and medium-penetration subbottom profiler. Take, by Level B
harassment only, of individuals of five species is anticipated to
result from the specified activity. This request is basically an
extension of the request made in April 2011 for survey activities that
were not completed under the previous IHA. CWA is not proposing to
change their survey activities in any way. However, the geotechnical
portion of the survey was completed in 2012 and would not be continued
during the 2013 season.
Description of the Specified Activity
CWA proposes to conduct a high resolution geophysical survey in
order to acquire remote-sensing data around Horseshoe Shoal which would
be used to characterize resources at or below the seafloor. The purpose
of the survey would be to identify any submerged cultural resources
that may be present and to generate additional data describing the
geological environment within the survey area. The survey would satisfy
the mitigation and monitoring requirements for ``cultural resources and
geology'' in the environmental stipulations of the Bureau of Ocean
Energy Management, Regulation, and Enforcement's lease. The survey is
part of the first phase of a larger Cape Wind energy project, which
involves the installation of 130 wind turbine generators on Horseshoe
Shoal over a 2-year period. The survey would collect data along
predetermined track lines using a towed array of instrumentation, which
would include a side scan sonar, magnetometer, shallow-penetration
subbottom profiler, multibeam depth sounder, and medium-penetration
subbottom profiler. The proposed high resolution geophysical survey
activities would not result in any disturbance to the sea floor.
Dates and Duration
Survey activities are necessary prior to construction of the wind
turbine array and are scheduled to begin in the spring of 2013,
continuing on a daily basis for up to five months. Survey vessels would
operate during daytime hours only and CWA estimates that one survey
vessel would cover about 17 Nautical miles (31 kilometers) of track
line per day. Therefore, CWA conservatively estimates that survey
activities would take 109 days (28 days less than what was expected
under the 2012 IHA). However, if more than one survey vessel is used,
the survey duration would be considerably shorter. NMFS is proposing to
issue an authorization that extends from April 1, 2013, to March 31,
2014.
Location
Survey vessels are expected to depart from Falmouth Harbor,
Massachusetts, or another nearby harbor on Cape Cod. In total, the
survey would cover approximately 110 square kilometers (km\2\). This
area includes the future location of the wind turbine generators--an
area about 8.4 km from Point Gammon, 17.7 km from Nantucket Island, and
8.9 km from Martha's Vineyard--and cables connecting the wind park to
the mainland. The survey area within the wind park would be transited
by survey vessels towing specialized equipment along primary track
lines and perpendicular tie lines. Preliminary survey designs include
primary track lines with northwest-southeast orientations and assume
30-meter (m) line spacing. Preliminary survey designs also call for tie
lines to likely run in a west-east orientation covering targeted areas
of the construction footprint where wind turbine generators would be
located. The survey area along the interconnecting submarine cable
route includes a construction and anchoring corridor, as part of the
wind farm's area of potential effect. The total track line distance
covered during the survey is estimated to be about 3,432 km (as opposed
to the 4,292 km included in the 2012 IHA).
Multiple survey vessels may operate within the survey area and
would travel at about 3 knots during data acquisition and approximately
15 knots during transit between the survey area and port. If multiple
vessels are used at the same time, they would be far enough apart that
sounds from the chirp and
[[Page 7404]]
boomer would not overlap. The survey vessels would acquire data
continuously throughout the survey area during the day and terminate
survey activities before dark, prior to returning to port. NMFS
believes that the likelihood of a survey vessel striking a marine
mammal is low considering the low marine mammal densities within
Nantucket Sound, the relatively short distance from port to the survey
site, the limited number of vessels, and the small vessel size. Vessel
sounds during survey activities would result from propeller
cavitations, propeller singing, propulsion, flow noise from water
dragging across the hull, and bubbles breaking in the wake. The
dominant sound source from vessels would be from propeller cavitations;
however, sounds resulting from survey vessel activity are considered to
be no louder than the existing ambient sound levels and sound generated
from regular shipping and boating activity in Nantucket Sound (MMS,
2009).
NMFS expects that acoustic stimuli resulting from the operation of
the survey equipment have the potential to harass marine mammals.
Background information on the characteristics and measurement of sound
are provided later in this document. The dominant sources of sound
during the proposed survey activities would be from the towed equipment
used to gather seafloor data. Two of the seismic survey devices used
during the high resolution geophysical survey emit sounds within the
hearing range of marine mammals in Nantucket Sound: Shallow-penetration
and medium-penetration subbottom profilers (known as a ``chirp'' and
``boomer,'' respectively). CWA would use a chirp to provide high
resolution data of the upper 15 m of sea bottom. An EdgeTech 216S or
similar model would be used. The chirp would be towed near the center
of the survey vessel directly adjacent to the gunwale of the boat,
about 1 to 1.5 m beneath the water's surface. Sources such as the chirp
are considered non-impulsive, intermittent (as opposed to continuous)
sounds. The frequency range for this instrument is generally 2 to 16
kilohertz (kHz)--a range audible by all marine mammal species in
Nantucket Sound. The estimated sound pressure level at the source would
be 201 dB re 1 [mu]Pa at 1 m with a typical pulse length of 32
milliseconds and a pulse repetition rate of 4 per second. NMFS does not
consider the chirp to be a continuous sound source (best represented by
vibratory pile driving or drilling). CWA would use a boomer to obtain
deeper resolution of geologic layering that cannot be imaged by the
chirp. An AP3000 (dual plate) boomer, or similar model would be used.
The boomer would be towed about 3 to 5 m behind the survey vessel's
stern at the water's surface. Unlike the chirp, the boomer emits an
impulse sound, characterized by a relatively rapid rise-time to maximum
pressure followed by a period of diminishing and oscillating pressures
(Southall et al., 2007). The boomer has a broad frequency range of 0.3
to 14 kHz--a range audible by all marine mammal species in Nantucket
Sound. CWA performed sound source verification monitoring in 2012 on
the type of chirp and boomer that would be used during the 2013 survey
season. Underwater sound was recorded with two Autonomous Multichannel
Acoustic Recorders, deployed 100 m apart, in the vicinity of the
project area. The received 90-percent rms sound pressure levels (SPLs)
from the subbottom profilers did not exceed 175 dB re 1uPa. The loudest
source, the dual-plate boomer, produced a received 90-percent rms SPL
of less than 140 dB re 1 uPa at a 500-m range. The distance to the 160-
dB isopleth was 12 m for the dual-plate boomer and 10 m for the chirp.
Description of Marine Mammals in the Area of the Specified Activity
All marine mammals with possible or confirmed occurrence in the
proposed activity area are listed in Table 1, along with their status
under the Endangered Species Act (ESA) and MMPA. In general, large
whales do not frequent Nantucket Sound, but they are discussed below
because some species have been reported near the project vicinity.
Table 1--Marine Mammals With Possible or Confirmed Occurrence in the Proposed Activity Area
----------------------------------------------------------------------------------------------------------------
Common name Scientific name ESA status MMPA status
----------------------------------------------------------------------------------------------------------------
Humpback whale....................... Megaptera novaeangilae. endangered............. depleted.
Fin whale............................ Balaenoptera physalus.. endangered............. depleted.
North Atlantic right whale........... Eubaelena glacialis.... endangered............. depleted.
Long-finned pilot whale.............. Globicephalus melas....
Minke whale.......................... Balaenoptera
acutorostrata.
Atlantic white-sided dolphin......... Lagenorhynchus acutus..
Striped dolphin...................... Stellena coeruleoalba..
Common dolphin....................... Delphinus delphis......
Harbor porpoise...................... Phocoena phocoena......
Atlantic spotted dolphin............. Stenella frontalis.....
Risso's dolphin...................... Grampus griseus........
Dwarf and pygmy sperm whale.......... Kogia spp..............
Gray seal............................ Halichoerus grypus.....
Harbor seal.......................... Phoca vitulina.........
Harp seal............................ Phoca groenlandica.....
Hooded seal.......................... Crystophora cristata...
----------------------------------------------------------------------------------------------------------------
Sightings data indicate that whales rarely visit Nantucket Sound
and there are no sightings of large whales on Horseshoe Shoal. Since
2002, no humpback whales have been observed anywhere in Nantucket Sound
and there are no documented occurrences of fin whales within Nantucket
Sound. Right whales are considered rare in Nantucket Sound and have not
been sighted on Horseshoe Shoal. All of the right whales observed in
Nantucket Sound during 2010 quickly transited the area and there is no
evidence of any persistent aggregations around the proposed project
area. The best available science indicates that humpback whales, fin
whales, and right whales--although present in the New England region--
are rare in Nantucket Sound and transient individuals may be
occasionally found 20 km from the proposed project area; this is likely
due to the shallow depths of Nantucket Sound and its location outside
of the coastal migratory corridor.
[[Page 7405]]
Likewise, sightings data shows no record of long-finned pilot
whales, striped dolphins, Atlantic spotted dolphins, common dolphins,
Risso's dolphins, Kogia species, harp seals, or hooded seals in
Nantucket Sound, although these stocks exist in the New England region.
Therefore, CWA is not requesting, nor is NMFS proposing, take for the
aforementioned species.
Marine mammals with known occurrences in Nantucket Sound that could
be harassed by high resolution geophysical survey activity in Nantucket
Sound are listed in Table 2. These are the species for which take is
being requested.
Table 2--Marine Mammals That Could Be Impacted by Survey Activities in Nantucket Sound
----------------------------------------------------------------------------------------------------------------
Time of year in New
Common name Scientific name Abundance Population status England
----------------------------------------------------------------------------------------------------------------
Minke whale..................... Balaenoptera 8,987 stable.............. April through
actuorostrata. October.
Atlantic white-sided dolphin.... Lagenorhynchus 63,000 n/a................. October through
acutus. December.
Harbor porpoise................. Phocoena phocoena.. 89,504 n/a................. Year-round (peak
Sept-Apr).
Gray seal....................... Halichoerus grypis. 250,000 increasing.......... Year-round.
Harbor seal..................... Phoca vitulina..... 99,340 n/a................. October through
April.
----------------------------------------------------------------------------------------------------------------
Minke Whales
In the North Atlantic, minke whales are found from Canada to the
Gulf of Mexico and concentrated in New England waters, particularly in
the spring and summer months. Minke whales found in Nantucket Sound are
part of the Canadian East Coast stock, which runs from the Davis Strait
down to the Gulf of Mexico. The best available abundance estimate for
this stock is 8,987 individuals. Sightings data indicate that minke
whales prefer shallower waters when in the Cape Cod vicinity, but
depths significantly greater than Nantucket Sound. Sightings per unit
effort estimates for Nantucket Sound are 0.1 to 5.9 minke whales per
1,000 km of survey track for spring and summer. However, estimates may
be biased due to heavier whale watching activities during those months.
Minke whales are one of the most abundant whale species in the world
and their population is considered stable throughout. The minke whale
is not listed under the ESA nor considered strategic under the MMPA.
Atlantic White-Sided Dolphin
Atlantic white-sided dolphins are found in temperate and sub-polar
waters of the North Atlantic, typically along the continental shelf and
slope. In the western North Atlantic, they are found from North
Carolina to Greenland. During summer months, Atlantic white-sided
dolphins move north and closer to shore. Atlantic white-sided dolphins
are rare in Nantucket Sound, but are found in deeper waters around
Massachusetts and Rhode Island. In 2011, the estimated population size
of the Western North Atlantic stock was about 23,390 animals. There is
insufficient data to determine population trends, but Atlantic white-
sided dolphins are not listed under the ESA, although they are
considered strategic under the MMPA.
Harbor Porpoises
Harbor porpoises have a wide and discontinuous range that includes
the North Atlantic and North Pacific. In the western North Atlantic,
harbor porpoises are found from Greenland to Cape Hatteras, North
Carolina. Harbor porpoises in U.S. waters are divided into 10 stocks,
based on genetics, movement patterns, and management. Any harbor
porpoises encountered during the proposed survey activities would be
part of the Gulf of Maine/Bay of Fundy stock which has an estimated
abundance of 89,054 animals and a minimum population estimate of 60,970
(NMFS, 2011c). They congregate around the Gulf of Maine during summer
months, but are otherwise dispersed along the east coast. No trend
analyses exist for this species. Harbor porpoises are not listed under
the ESA although they are considered strategic under the MMPA.
Gray Seals
Gray seals inhabit temperate and sub-arctic waters. They are found
from Maine to Long Island Sound, live on remote, exposed islands,
shoals, and unstable sandbars, and are the second most common pinniped
along the U.S. Atlantic coast. Three major populations exist in eastern
Canada, northwestern Europe, and the Baltic Sea. The western North
Atlantic stock is equivalent to the eastern Canada population and
ranges from New York to Labrador. Pupping occurs on land or ice from
late December through mid-February with peaks in mid-January. Muskeget
Island (located between Martha's Vineyard and Nantucket Island) and
Monomoy Island (at the eastern limit of Nantucket Sound) are the only
gray seal breeding colonies in the U.S. and the southernmost gray seal
breeding colonies in the world. These breeding colonies are about 24 km
and 14 km from the proposed project site, respectively. Gray seals
presently use the islands as areas to give birth and raise their pups.
There is no defined migratory behavior for gray seals, so a large
portion of the population may be present in Nantucket Sound year-round.
Some adults move north during spring and summer, out of Nantucket Sound
to the waters off Maine and Canada, but others have been observed in
high abundance in Chatham Harbor, MA and other areas of lower Cape Cod
during this time.
Incidental observations of seals were recorded during avian aerial
surveys conducted independently by CWA and the Massachusetts Audubon
Society. Between May 2002 and February 2004, CWA conducted about 46
aerial avian surveys in Nantucket Sound, with particular focus on
Horseshoe Shoal. During this time, about 26,873 seals were observed
throughout Nantucket Sound; about 56 of these were observed within the
proposed project area over the three-year period. Current population
numbers for the western North Atlantic stock are unknown, but some pup
surveys suggest about 223,220 animals. Gray seal numbers are increasing
in coastal waters between southern Massachusetts and eastern Long
Island. Their abundance is likely increasing throughout the western
Atlantic, but the rate of increase is unknown. Gray seals are not
listed under the ESA, nor considered strategic under the MMPA.
Harbor Seals
Harbor seals, also known as common seals, are found throughout
coastal waters of the Atlantic Ocean and considered the most abundant
pinniped on the U.S. east coast. The best available estimate for the
harbor seal population along the New England coast is 99,340 (NMFS,
2011f). They are most common around coastal islands, ledges, and
sandbars above 30[deg] N latitude and range
[[Page 7406]]
from the Arctic down to Nantucket Sound. Harbor seals are seasonal
visitors to Massachusetts; breeding and pupping occur through the
spring and summer in Maine and Canada. Harbor seals typically over-
winter in Massachusetts, but some remain in southern New England year-
round. No pupping areas have been identified in southern New England.
Extensive sand spits off Muskeget Island and neighboring Tuckernuck and
Skiff Islands have been identified as preferred haul-out spots for
large numbers of harbor seals.
Harbor seal abundance estimates for Nantucket Sound are scarce.
Barlas (1999) observed harbor seals on Cape Cod from October through
April and saw abundance peak in March, with very few individuals using
haul-out sites in Nantucket Sound. Waring (unpublished data, 2002)
observed an increased abundance of harbor seals on Muskeget Island,
Monomoy Island, and Tuckernuck Island in 1999 and 2000; however, harbor
seals are not likely to be in the same area when gray seals are
breeding.
Further information on the biology and local distribution of these
species and others in the region can be found in CWA's application,
which is available online at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications, and the NMFS Marine Mammal Stock
Assessment Reports, which are available online at: http://www.nmfs.noaa.gov/pr/species.
Potential Effects of the Specified Activity on Marine Mammals
Use of subbottom profilers on Horseshoe Shoal may temporarily
impact marine mammal behavior within the survey area due to elevated
in-water sound levels. Marine mammals are continually exposed to many
sources of sound. Naturally occurring sounds such as lightning, rain,
sub-sea earthquakes, and biological sounds (for example, snapping
shrimp, whale songs) are widespread throughout the world's oceans.
Marine mammals produce sounds in various contexts and use sound for
various biological functions including, but not limited to, (1) social
interactions; (2) foraging; (3) orientation; and (4) predator
detection. Interference with producing or receiving these sounds may
result in adverse impacts. Audible distance, or received levels of
sound depend on the nature of the sound source, ambient noise
conditions, and the sensitivity of the receptor to the sound
(Richardson et al., 1995). Type and significance of marine mammal
reactions to sound are likely dependent on a variety of factors
including, but not limited to, (1) the behavioral state of the animal
(for example, feeding, traveling, etc.); (2) frequency of the sound;
(3) distance between the animal and the source; and (4) the level of
the sound relative to ambient conditions (Southall et al., 2007).
For background, sound is a physical phenomenon consisting of minute
vibrations that travel through a medium, such as air or water, and is
generally characterized by several variables. Frequency describes the
sound's pitch and is measured in hertz (Hz) or kilohertz (kHz), while
sound level describes the sound's intensity and is measured in decibels
(dB). Sound level increases or decreases exponentially with each dB of
change. The logarithmic nature of the scale means that each 10-dB
increase is a 10-fold increase in acoustic power (and a 20-dB increase
is then a 100-fold increase in power). A 10-fold increase in acoustic
power does not mean that the sound is perceived as being 10 times
louder, however. Sound levels are compared to a reference sound
pressure (micro-Pascal) to identify the medium. For air and water,
these reference pressures are ``re: 20 [mu]Pa'' and ``re: 1 [mu]Pa,''
respectively. Root mean square (RMS) is the quadratic mean sound
pressure over the duration of an impulse. RMS is calculated by squaring
all of the sound amplitudes, averaging the squares, and then taking the
square root of the average (Urick, 1975). RMS accounts for both
positive and negative values; squaring the pressures makes all values
positive so that they may be accounted for in the summation of pressure
levels (Hastings and Popper, 2005). This measurement is often used in
the context of discussing behavioral effects, in part because
behavioral effects, which often result from auditory cues, may be
better expressed through averaged units rather than by peak pressures.
Cetaceans are divided into three functional hearing groups: Low-
frequency, mid-frequency, and high-frequency. Minke whales are
considered low-frequency cetaceans and their estimated auditory
bandwidth (lower to upper frequency hearing cut-off) ranges from 7 Hz
to 30 kHz. Atlantic white-sided dolphins are considered mid-frequency
cetaceans and their estimated auditory bandwidth ranges from 150 Hz to
160 kHz. Lastly, harbor porpoises are considered high-frequency
cetaceans and their estimated auditory bandwidth ranges from 200 Hz to
180 kHz. In contrast, pinnipeds are divided into two functional hearing
groups: In-water and in-air. Pinnipeds in water have an estimated
auditory bandwidth of 75 Hz to 75 kHz. There are no pinniped haul-outs
close enough to the survey area to take in-air auditory bandwidths into
consideration.
Hearing Impairment
Marine mammals may experience temporary or permanent hearing
impairment when exposed to loud sounds. Hearing impairment is
classified by temporary threshold shift (TTS) and permanent threshold
shift (PTS). There are no empirical data for onset of PTS in any marine
mammal; 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 (that is, 40 dB
of TTS). PTS is considered auditory injury (Southall et al., 2007) and
occurs in a specific frequency range and amount. Irreparable damage to
the inner or outer cochlear hair cells may cause PTS; however, other
mechanisms are also involved, such as exceeding the elastic limits of
certain tissues and membranes in the middle and inner ears and
resultant changes in the chemical composition of the inner ear fluids
(Southall et al., 2007). Due to proposed mitigation measures and source
levels, NMFS does not expect marine mammals to be exposed to PTS levels
during the proposed survey activities.
Temporary Threshold Shift (TTS)
TTS is the mildest form of hearing impairment that can occur during
exposure to a loud sound (Kryter, 1985). While experiencing TTS, the
hearing threshold rises and a sound must be stronger in order to be
heard. At least in terrestrial mammals, TTS can last from minutes or
hours to (in cases of strong TTS) days, can be limited to a particular
frequency range, and can occur to varying degrees (i.e., a loss of a
certain number of dBs of sensitivity). For sound exposures at or
somewhat above the TTS threshold, hearing sensitivity in both
terrestrial and marine mammals recovers rapidly after exposure to the
noise ends.
Marine mammal hearing plays a critical role in communication with
conspecifics and in interpretation of environmental cues for purposes
such as predator avoidance and prey capture. Depending on the degree
(elevation of threshold in dB), duration (i.e., recovery time), and
frequency range of TTS and the context in which it is experienced, TTS
can have effects on marine mammals ranging from discountable to
serious. For example, a marine mammal may be able to readily compensate
for a brief, relatively small amount of TTS
[[Page 7407]]
in a non-critical frequency range that takes place during a time when
the animals is traveling through the open ocean, where ambient noise is
lower and there are not as many competing sounds present.
Alternatively, a larger amount and longer duration of TTS sustained
during a time when communication is critical for successful mother/calf
interactions could have more serious impacts if it were in the same
frequency band as the necessary vocalizations and of a severity that it
impeded communication. The fact that animals exposed to levels and
durations of sound that would be expected to result in this
physiological response would also be expected to have behavioral
responses of a comparatively more severe or sustained nature is also
notable and potentially of more importance than the simple existence of
a TTS.
Recent literature highlights the inherent complexity of predicting
TTS onset in marine mammals, as well as the importance of considering
exposure duration when assessing potential impacts (Mooney et al.,
2009a, 2009b; Kastak et al., 2007). Generally, with sound exposures of
equal energy, quieter sounds (lower SPL) of longer duration were found
to induce TTS onset more than louder sounds (higher SPL) of shorter
duration (more similar to subbottom profilers). For intermittent
sounds, less threshold shift will occur than from a continuous exposure
with the same energy (some recovery will occur between intermittent
exposures) (Kryter et al., 1966; Ward, 1997). For sound exposures at or
somewhat above the TTS-onset threshold, hearing sensitivity recovers
rapidly after exposure to the sound ends. Southall et al. (2007)
considers a 6 dB TTS (that is, baseline thresholds are elevated by 6
dB) to be a sufficient definition of TTS-onset. NMFS considers TTS as
Level B harassment that is mediated by physiological effects on the
auditory system; however, NMFS does not consider TTS-onset to be the
lowest level at which Level B harassment may occur. Southall et al.
(2007) summarizes underwater pinniped data from Kastak et al. (2005),
indicating that a tested harbor seal showed a TTS of around 6 dB when
exposed to a nonpulse noise at sound pressure level 152 dB re: 1 [mu]Pa
for 25 minutes.
Some studies suggest that harbor porpoises may be more sensitive to
sound than other odontocetes (Lucke et al., 2009; Kastelein et al.,
2011). While TTS onset may occur in harbor porpoises at lower received
levels (when compared to other odontocetes), NMFS 160-dB threshold
criteria are based on the onset of behavioral harassment, not the onset
of TTS. The potential for TTS is considered within NMFS' analysis of
potential impacts from Level B harassment.
Behavioral Disturbance
Behavioral responses to sound are highly variable and context-
specific. An animal's perception of and response to (in both nature and
magnitude) an acoustic event can be influenced by prior experience,
perceived proximity, bearing of the sound, familiarity of the sound,
etc. (Southall et al., 2007). If a marine mammal does react briefly to
an underwater sound by changing its behavior or moving a small
distance, the impacts of the change are unlikely to be significant to
the individual, let alone the stock or population. However, if a sound
source displaces marine mammals from an important feeding or breeding
area for a prolonged period, impacts on individuals and populations
could be significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007).
Given the many uncertainties in predicting the quantity and types of
impacts of noise on marine mammals, it is common practice to estimate
how many mammals would be present within a particular distance of
activities and/or exposed to a particular level of sound. In most
cases, this approach likely overestimates the numbers of marine mammals
that would be affected in some biologically-important manner.
The studies that address responses of low-frequency cetaceans (such
as the minke whale) to non-pulse sounds include data gathered in the
field and related to several types of sound sources (of varying
similarity to chirps), including: Vessel noise, drilling and machinery
playback, low-frequency M-sequences (sine wave with multiple phase
reversals) playback, tactical low-frequency active sonar playback,
drill ships, and non-pulse playbacks. These studies generally indicate
no (or very limited) responses to received levels in the 90 to 120 dB
re: 1[mu]Pa range and an increasing likelihood of avoidance and other
behavioral effects in the 120 to 160 dB range. As mentioned earlier,
though, contextual variables play a very important role in the reported
responses and the severity of effects are not linear when compared to
received level. Also, few of the laboratory or field datasets had
common conditions, behavioral contexts, or sound sources, so it is not
surprising that responses differ.
The studies that address responses of mid-frequency cetaceans (such
as Atlantic white-sided dolphins) to non-pulse sounds include data
gathered both in the field and the laboratory and related to several
different sound sources (of varying similarity to chirps) including:
Pingers, drilling playbacks, ship and ice-breaking noise, vessel noise,
Acoustic harassment devices (AHDs), Acoustic Deterrent Devices (ADDs),
mid-frequency active sonar, and non-pulse bands and tones. Southall et
al. (2007) were unable to come to a clear conclusion regarding the
results of these studies. In some cases animals in the field showed
significant responses to received levels between 90 and 120 dB, while
in other cases these responses were not seen in the 120 to 150 dB
range. The disparity in results was likely due to contextual variation
and the differences between the results in the field and laboratory
data (animals typically responded at lower levels in the field).
The studies that address responses of high-frequency cetaceans
(such as the harbor porpoise) to non-pulse sounds include data gathered
both in the field and the laboratory and related to several different
sound sources (of varying similarity to chirps), including: Pingers,
AHDs, and various laboratory non-pulse sounds. All of these data were
collected from harbor porpoises. Southall et al. (2007) concluded that
the existing data indicate that harbor porpoises are likely sensitive
to a wide range of anthropogenic sounds at low received levels (around
90 to 120 dB), at least for initial exposures. All recorded exposures
above 140 dB induced profound and sustained avoidance behavior in wild
harbor porpoises (Southall et al., 2007). Rapid habituation was noted
in some but not all studies.
The studies that address the responses of pinnipeds in water to
non-pulse sounds include data gathered both in the field and the
laboratory and related to several different sound sources (of varying
similarity to chirps), including: AHDs, various non-pulse sounds used
in underwater data communication, underwater drilling, and construction
noise. Few studies exist with enough information to include them in the
analysis. The limited data suggest that exposures to non-pulse sounds
between 90 and 140 dB generally do not result in strong behavioral
responses of pinnipeds in water, but no data exist at higher received
levels (Southall et al., 2007).
Southall et al. (2007) also addressed behavioral responses of
marine mammals to impulse sounds. The studies that address the
responses of low-frequency cetaceans to impulse sounds include data
gathered in the field and related to two sound sources: Airguns and
explosions. The onset of
[[Page 7408]]
significant behavioral disturbance varied between 120 and 160 dB,
depending on species. The studies that address the responses of mid-
frequency cetaceans to impulse sounds include data gathered both in the
field and the laboratory and related to several different sound sources
(of varying similarity to boomers), including: Small explosives, airgun
arrays, pulse sequences, and natural and artificial pulses. The data
show no clear indication of increasing probability and severity of
response with increasing received level. Behavioral responses seem to
vary depending on species and stimuli. Data on behavioral responses of
high-frequency cetaceans to multiple pulses is not available. Although
individual elements of some non-pulse sources (such as pingers) could
be considered pulses, it is believed that some mammalian auditory
systems perceive them as non-pulse sounds (Southall et al., 2007).
The studies that address the responses of pinnipeds in water to
impulse sounds include data gathered in the field and related to
several different sources (of varying similarity to boomers),
including: Small explosives, impact pile driving, and airgun arrays.
Quantitative data on reactions of pinnipeds to impulse sounds is
limited, but a general finding is that exposures in the 150 to 180 dB
range generally have limited potential to induce avoidance behavior
(Southall et al., 2007).
Any impacts to marine mammal behavior are expected to be temporary.
Animals may avoid the area around the survey vessels, thereby reducing
exposure. Any disturbance to marine mammals is likely to be in the form
of temporary avoidance or alteration of opportunistic foraging behavior
near the survey location. In addition, because protected species
observers would be monitoring a 500-m exclusion zone (much larger than
the 30-m, 180-dB isopleth in which Level A harassment could occur),
marine mammal injury or mortality is not anticipated. The protected
species observers would be on watch to stop survey activities, a
mitigation measure designed to prevent animals from being exposed to
injurious level sounds. For these reasons, any changes to marine mammal
behavior are expected to be temporary and result in a negligible impact
to affected species and stocks.
Anticipated Effects on Habitat
There is no anticipated impact on marine mammal habitat from the
proposed survey activities. The high resolution geophysical survey
equipment would not come in contact with the seafloor and would not be
a source of air or water pollution. Marine mammals may avoid the survey
area temporarily due to ensonification, but survey activities are not
expected to result in long-term abandonment of marine mammal habitat. A
negligible area of seafloor would be temporarily disturbed during the
collection of geotechnical data.
Overall, the proposed activity is not expected to cause significant
impacts on marine mammal habitat or marine mammal prey species in the
proposed survey area. Therefore, NMFS has preliminarily determined
impacts to marine mammal habitat are negligible.
Proposed Mitigation
In order to issue an incidental take authorization under section
101(a)(5)(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 subsistence uses where relevant.
CWA proposed, with NMFS' guidance, the following mitigation
measures to help ensure the least practicable adverse impact on marine
mammals:
Establishment of an Exclusion Zone
During all survey activities involving the shallow-penetration and
medium-penetration subbottom profilers, CWA would establish a 500-m
radius exclusion zone around each survey vessel. This area would be
monitored for marine mammals 60 minutes (as stipulated by the BOEMRE
lease) prior to starting or restarting surveys, and during surveys, and
60 minutes after survey equipment has been turned off. Typically, the
exclusion zone is based on the area in which marine mammals could be
exposed to injurious (Level A) levels of sound. CWA's lease specifies a
500-m exclusion zone, which exceeds both the estimated Level A and
Level B isopleths for marine mammal harassment. CWA's proposed
exclusion zone would minimize impacts to marine mammals from increased
sound exposures. The exclusion zone must not be obscured by fog or poor
lighting conditions.
Shut Down and Delay Procedures
If a protected species observer sees a marine mammal within or
approaching the exclusion zone prior to the start of surveying, the
observer would notify the appropriate individual who would then be
required to delay surveying until the marine mammal moves outside of
the exclusion zone or if the animal has not been resighted for 60
minutes. If a protected species observer sees a marine mammal within or
approaching the exclusion zone during survey activities, the observer
would notify the appropriate individual who would then be required to
shut down surveying until the marine mammal moves outside of the
exclusion zone or if the animal has not been resighted for 60 minutes.
Soft-start Procedures
A ``soft-start'' technique would be used at the beginning of survey
activities each day (or following a shut down) to allow any marine
mammal that may be in the immediate area to leave before the sound
sources reach full energy. Surveys shall not commence at nighttime or
when the exclusion zone cannot be effectively monitored.
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 adverse 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, and
practicality of implementation.
Based on our evaluation of the applicant's proposed measures, as
well as other measures considered by NMFS, NMFS has preliminarily
determined that the proposed mitigation measures provide the means of
effecting the least practicable adverse impacts on marine mammals
species or stocks and their habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance.
Proposed Monitoring and Reporting
In order to issue an incidental take statement for an activity,
section 101(a)(5)(D) of the MMPA states that NMFS must set forth, where
applicable, ``requirements pertaining to the monitoring and reporting
of such taking.'' The MMPA implementing
[[Page 7409]]
regulations at 50 CFR 216.104(a)(13) indicate that requests for
incidental take authorizations must include the suggested means of
accomplishing the necessary monitoring and reporting that will result
in increased knowledge of the species and of the level of taking or
impacts on populations of marine mammals that are expected to be
present in the proposed action area.
Visual Monitoring
CWA would designate at least one biologically-trained, on-site
individual, approved in advance by NMFS, to monitor the area for marine
mammals 60 minutes before, during, and 60 minutes after all survey
activities and call for shut down if any marine mammal is observed
within or approaching the designated 500-m exclusion zone. Should a
marine mammal not included in an incidental take authorization be
observed at any time within the 500-m exclusion zone, shut down and
delay procedures would be followed.
CWA would also provide additional monitoring efforts that would
result in increased knowledge of marine mammal species in Nantucket
Sound. At least one NMFS-approved protected species observer would
conduct behavioral monitoring from the survey vessel for two days for
every 14 days of survey activity to estimate take and evaluate the
behavioral impacts that survey activities have on marine mammals
outside of the 500-m exclusion zone. In addition, CWA would also send
out an additional vessel with a NMFS-approved protected species
observer to collect data on species presence and behavior before
surveys begin and once a month during survey activities.
Protected species observers would be provided with the equipment
necessary to effectively monitor for marine mammals (for example, high-
quality binoculars, compass, and range-finder) in order to determine if
animals have entered into the harassment isopleths and to record marine
mammal sighting information. Protected species observers must be able
to effectively monitor the 500-m exclusion zone whenever the subbottom
profilers are in use. Survey efforts would only take place during
daylight hours and visibility must not be obscured by fog, lighting
conditions, etc.
CWA would submit a report to NMFS within 90 days of expiration of
the IHA or completion of surveying, whichever comes first. The report
would provide full documentation of methods, results, and
interpretation pertaining to all monitoring. More specifically, the
report would include the following information when a marine mammal is
sighted:
Dates, times, locations, heading, speed, weather, sea
conditions (including Beaufort sea state and wind force), and
associated activities during all survey operations and marine mammal
sightings;
Species, number, location, distance from the vessel, and
behavior of any marine mammals, as well as associated survey activity
(number of shut-downs or delays), observed throughout all monitoring
activities;
An estimate of the number (by species) of marine mammals
that are known to have been exposed to the survey activity (based on
visual observation) at received levels greater than or equal to 160 dB
re 1 uPa (rms) and/or 180 dB re 1 uPa (rms) for cetaceans and 190 dB re
1 uPa (rms) for pinnipeds with a discussion of any specific behaviors
those individuals exhibited; and
A description of the implementation and effectiveness of
the mitigation measures of the IHA.
In the unanticipated event that the specified activity clearly
causes the take of a marine mammal in a manner prohibited by the IHA,
such as an injury (Level A harassment), serious injury, or mortality
(e.g., ship-strike, gear interaction, and/or entanglement), CWA would
immediately cease the specified activities and report the incident to
the Chief of the Permits and Conservation Division, Office of Protected
Resources, NMFS, at 301-427-8401 and/or by email to
Michael.Payne@noaa.gov and ITP.Magliocca@noaa.gov and the Northeast
Regional Stranding Coordinator at 978-281-9300 (Mendy.Garron@noaa.gov).
The report must include the following information:
Time, date, and location (latitude/longitude) of the
incident;
Name and type of vessel involved;
Vessel's speed during and leading up to the incident;
Description of the incident;
Status of all sound source use in the 24 hours preceding
the incident;
Water depth;
Environmental conditions (e.g., wind speed and direction,
Beaufort sea state, cloud cover, and visibility);
Description of all marine mammal observations in the 24
hours preceding the incident;
Species identification or description of the animal(s)
involved;
Fate of the animal(s); and
Photographs or video footage of the animal(s) (if
equipment is available).
Activities would not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS would work with CWA to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. CWA may not resume their
activities until notified by NMFS via letter, email, or telephone.
In the event that CWA discovers an injured or dead marine mammal,
and the lead PSO determines that the cause of the injury or death is
unknown and the death is relatively recent (i.e., in less than a
moderate state of decomposition as described in the next paragraph),
CWA would immediately report the incident to the Chief of the Permits
and Conservation Division, Office of Protected Resources, NMFS, at 301-
427-8401 and/or by email to Michael.Payne@noaa.gov and
ITP.Magliocca@noaa.gov and the Northeast Regional Stranding Coordinator
at 978-281-9300 (Mendy.Garron@noaa.gov). The report must include the
same information identified in the paragraph above. Activities may
continue while NMFS reviews the circumstances of the incident. NMFS
would work with CWA to determine whether modifications in the
activities are appropriate.
In the event that CWA discovers an injured or dead marine mammal,
and the lead PSO determines that the injury or death is not associated
with or related to the activities authorized in the IHA (e.g.,
previously wounded animal, carcass with moderate to advanced
decomposition, or scavenger damage), CWA would report the incident to
the Chief of the Permits and Conservation Division, Office of Protected
Resources, NMFS, at 301-427-8401 and/or by email to
Michael.Payne@noaa.gov and ITP.Magliocca@noaa.gov and the Northeast
Regional Stranding Coordinator at 978-281-9300 (Mendy.Garron@noaa.gov),
within 24 hours of the discovery. CWA would provide photographs or
video footage (if available) or other documentation of the stranded
animal sighting to NMFS.
Summary of Past Monitoring and Reporting
CWA complied with the requirements under their 2012 IHA. CWA
completed 28 days and 459 nautical transect miles of survey activity
during 2012 and no living marine mammals were sighted. On July 10,
2012, a deceased harbor seal was seen by two protected species
observers and survey equipment was immediately shut down. The observers
determined that the seal had been deceased for 24-48 hours, based on
signs of scavenger damage and bloating, which suggest moderate
decomposition (Pugliares et al., 2007). Both observers
[[Page 7410]]
concurred that the animal was not injured due to survey activities;
however, a 60-minute post watch was performed to ensure that no other
protected species were in the vicinity. A full report was submitted to
NMFS on July 11, 2012, within 24 hours of the initial sighting. No
marine mammal takes were reported during the 2012 season. CWA's
monitoring report is available online at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.
Estimated Take by Incidental Harassment
Except with respect to certain activities not pertinent here, the
MMPA defines ``harassment'' as: Any act of pursuit, torment, or
annoyance which (i) has the potential to injure a marine mammal or
marine mammal stock in the wild [Level A harassment]; or (ii) has the
potential to disturb a marine mammal or marine mammal stock in the wild
by causing disruption of behavioral patterns, including, but not
limited to, migration, breathing, nursing, breeding, feeding, or
sheltering [Level B harassment].
Based on CWA's application and NMFS' subsequent analysis, the
impact of the described survey activities may result in, at most,
short-term modification of behavior by small numbers of marine mammals
within the action area. Marine mammals may avoid the area or change
their behavior at time of exposure to elevated sound levels.
Current NMFS practice regarding exposure of marine mammals to
anthropogenic sound is that in order to avoid the potential for injury
of marine mammals (for example, PTS), cetaceans and pinnipeds should
not be exposed to impulsive sounds of 180 and 190 dB re: 1 [mu]Pa or
above, respectively. This level is considered precautionary as it is
likely that more intense sounds would be required before injury would
actually occur (Southall et al., 2007). Potential for behavioral
harassment (Level B) is considered to have occurred when marine mammals
are exposed to sounds at or above 160 dB re: 1 [mu]Pa for impulse
sounds and 120 dB re: 1 [mu]Pa for non-pulse noise, but below the
aforementioned thresholds. These levels are also considered
precautionary.
CWA estimated the number of potential takes resulting from survey
activities by considering species density, the zone of influence, and
duration of survey activities. More specifically, take estimates were
calculated by multiplying the estimated species density values (n)
measured in individuals per square kilometers, by the area of the zone
of influence in km\2\, times the total number of survey days (d = 109).
The zone of influence was calculated as a function of the distance a
survey vessel with deployed boomer would travel in one survey day and
the area around the boomer where sound levels reach or exceed 160 dB.
For consistency with the 2011 IHA, the take estimate is based on a zone
of influence equal to 444 m (the initial estimate for the 160 dB
isopleth for the boomer), although based on acoustic measurements taken
at the beginning of the 2012 survey, the 160 dB isopleth is thought to
be much smaller. This distance was applied consistently to all marine
mammal species.
Estimated numbers of species potentially exposed to disturbing
levels of sound from the boomer (the survey equipment with the largest
160 dB isopleth) were calculated for minke whales, Atlantic white-sided
dolphins, harbor porpoises, gray seals, and harbor seals. These
estimates were calculated by multiplying the low and high end of the
ranges of species density by the boomer's zone of influence and the
number of days of survey operation. CWA calculated seal density
estimates based on aerial survey counts for seals observed swimming
and/or foraging in open water within the activity area. CWA included an
adjustment factor in these density calculations for seals not seen, but
considered present during aerial surveys. Density estimates for seals
based on haul out counts were not used due to the distance of haul outs
from the activity area (about 20 km to Monomoy Island and 12 km to
Muskeget Island). Gray seals and harbor seals congregating in these
locations are not expected to hear sounds from the survey equipment at
160 dB or higher. The seals most likely to be exposed to potentially
disturbing sounds are the individuals swimming and/or foraging within
the zone of influence for the activated medium-penetration subbottom
profiler.
CWA is requesting incidental take based on the highest estimated
possible species exposures to potentially disturbing levels of sound
from the boomer. No marine mammals are expected to be exposed to
injurious levels of sound in excess of 180 dB during survey activities.
CWA is requesting, and NMFS is proposing, Level B harassment of 9 minke
whales, 185 Atlantic white-sided dolphins, 110 harbor porpoises, 314
gray seals, and 79 harbor seals. These numbers overestimate the number
of animals likely to be taken because they are based on the highest
density estimates and do not account for proposed mitigation measures
(such as the 500-m exclusion zone, marine mammal monitoring, and ramp
up procedures). These numbers indicate the maximum number of animals
expected to occur within 444 m of the boomer. Estimated and proposed
level of take of each species is less than one percent of each affected
stock and therefore is considered small in relation to the stock
estimates previously set forth.
Negligible Impact and Small Numbers Analysis and Determination
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 number of factors which include, but are not limited
to, number of anticipated injuries or mortalities (none of which would
be authorized here), number, nature, intensity, and duration of Level B
harassment, and the context in which takes occur (for instance, will
the takes occur in an area or time of significance for marine mammals,
or are takes occurring to a small, localized population?).
As described above, marine mammals would not be exposed to
activities or sound levels which would result in injury (for instance,
PTS), serious injury, or mortality. Anticipated impacts of survey
activities on marine mammals are temporary behavioral changes due to
avoidance of the area. All marine mammals in the vicinity of survey
operations would be transient as no breeding, calving, pupping, or
nursing areas, or haul-outs, overlap with the survey area. The closest
pinniped haul-outs are about 20 km and 12 km away on Monomoy Island and
Muskeget Island, respectively. Marine mammals approaching the survey
area would likely be traveling or opportunistically foraging. The
amount of take CWA requested, and NMFS proposes to authorize, is
considered small (less than one percent) relative to the estimated
populations of 8,987 minke whales, 23,390 Atlantic white-sided
dolphins, 89,054 harbor porpoises, 250,000 gray seals, and 99,340
harbor seals. Furthermore, the amount of take CWA requested and NMFS
proposes to authorize likely overestimates the actual take that would
occur; no marine mammal takes were observed during 28 days of survey
activity in 2012. No affected marine mammals are listed under the ESA
and only the Atlantic white-sided dolphin and harbor porpoise are
considered strategic under the MMPA. Marine mammals are
[[Page 7411]]
expected to avoid the survey area, thereby reducing exposure and
impacts. No disruption to reproductive behavior is anticipated and
there is no anticipated effect on annual rates of recruitment or
survival of affected marine mammals.
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 determines that CWA's survey activities
would result in the incidental take of small numbers of marine mammals,
by Level B harassment, and that the total taking would have a
negligible impact on the affected species or stocks.
Impact on Availability of Affected Species for Taking for Subsistence
Uses
There are no relevant subsistence uses of marine mammals implicated
by this action.
Endangered Species Act (ESA)
No marine mammal species listed under the ESA are anticipated to
occur within the action area. Therefore, section 7 consultation under
the ESA is not required.
National Environmental Policy Act (NEPA)
In compliance with the National Environmental Policy Act of 1969
(42 U.S.C. 4321 et seq.), as implemented by the regulations published
by the Council on Environmental Quality (40 CFR parts 1500-1508), and
NOAA Administrative Order 216-6, NMFS prepared an Environmental
Assessment (EA) to consider the direct, indirect, and cumulative
effects to marine mammals and other applicable environmental resources
resulting from issuance of a one-year IHA and the potential issuance of
additional authorization for incidental harassment for the ongoing
project in 2012. This analysis is still considered relevant for the
proposed IHA because the applicant's proposed activity has not changed.
This EA is available on the NMFS Web site listed in the beginning of
this document.
Dated: January 29, 2013.
Helen M. Golde,
Acting Director, Office of Protected Resources, National Marine
Fisheries Service.
[FR Doc. 2013-02195 Filed 1-31-13; 8:45 am]
BILLING CODE 3510-22-P