[Federal Register Volume 79, Number 49 (Thursday, March 13, 2014)]
[Notices]
[Pages 14219-14237]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2014-05396]
[[Page 14219]]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XC779
Takes of Marine Mammals Incidental to Specified Activities; Low-
Energy Marine Geophysical Survey in the Dumont d'Urville Sea off the
Coast of East Antarctica, January to March 2014
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; issuance of an Incidental Take Authorization (ITA).
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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA)
regulations, notification is hereby given that NMFS has issued an
Incidental Harassment Authorization (IHA) to the National Science
Foundation (NSF), Division of Polar Programs, and Antarctic Support
Contract (ASC) on behalf of five research institutions: Colgate
University, Columbia University, Texas A&M Research Foundation,
University of South Florida, and University of Texas at Austin, to take
marine mammals, by Level B harassment only, incidental to conducting a
low-energy marine geophysical (seismic) survey in the Dumont d'Urville
Sea off the coast of East Antarctica, January to March 2014.
DATES: Effective January 31 through April 27, 2014.
ADDRESSES: A copy of the final IHA and application are available by
writing to Jolie Harrison, Supervisor, Incidental Take Program, Permits
and Conservation Division, Office of Protected Resources, National
Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD
20910, by telephoning the contacts listed here, or by visiting the
Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.
NSF and ASC have provided an ``Initial Environmental Evaluation/
Environmental Assessment to Conduct Marine-Based Studies of the Totten
Glacier System and Marine Record of Cryosphere--Ocean Dynamics'' (IEE/
EA), prepared by AECOM, on behalf of NSF and ASC, which is also
available at the same Internet address. NMFS also issued a Biological
Opinion under section 7 of the Endangered Species Act (ESA) to evaluate
the effects of the survey and IHA on marine species listed as
threatened and endangered. The NMFS Biological Opinion is available
online at: http://www.nmfs.noaa.gov/pr/consultations/opinions.htm.
Documents cited in this notice may be viewed, by appointment, during
regular business hours, at the aforementioned address.
FOR FURTHER INFORMATION CONTACT: Howard Goldstein or Jolie Harrison,
Office of Protected Resources, NMFS, 301-427-8401.
SUPPLEMENTARY INFORMATION:
Background
Section 101(a)(5)(D) of the MMPA, as amended (16 U.S.C. 1371
(a)(5)(D)), directs the Secretary of Commerce (Secretary) to authorize,
upon request, the incidental, but not intentional, taking of small
numbers of marine mammals of a species or population stock, by United
States citizens who engage in a specified activity (other than
commercial fishing) within a specified geographical region if certain
findings are made and, if the taking is limited to harassment, a notice
of a proposed authorization is provided to the public for review.
Authorization for the incidental taking of small numbers of marine
mammals shall be granted if NMFS finds that the taking will have a
negligible impact on the species or stock(s), and will not have an
unmitigable adverse impact on the availability of the species or
stock(s) for subsistence uses (where relevant). The authorization must
set forth the permissible methods of taking, other means of effecting
the least practicable adverse impact on the species or stock and its
habitat, and requirements pertaining to the mitigation, monitoring and
reporting of such takings. 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.''
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 July 3, 2013, NMFS received an application from the NSF and ASC
requesting that NMFS issue an IHA for the take, by Level B harassment
only, of small numbers of marine mammals incidental to conducting a
low-energy marine seismic survey in International Waters (i.e., high
seas) and in the Southern Ocean off the coast of East Antarctica during
January to March 2014. Per NMFS request, NMFS received an addendum to
the application from the NSF and ASC on December 18, 2013, which
reflected updates to incidental take requests for marine mammals
related to icebreaking activities.
The research will be conducted by five research institutions:
Colgate University, Columbia University, Texas A&M Research Foundation,
University of South Florida, and University of Texas at Austin. The NSF
and ASC plan to use one source vessel, the RVIB Nathaniel B. Palmer
(Palmer), and a seismic airgun array to collect seismic data in the
Southern Ocean. The vessel will be operated by Edison Chouest Offshore,
Inc., a subcontractor to ASC, which operates the United States
Antarctic Program under contract to the NSF. In support of the United
States Antarctic Program, the NSF and ASC plan to use conventional low-
energy, seismic methodology to perform marine-based studies in the
Dumont d'Urville Sea to include evaluation of geophysical and physical
oceanographic features in two areas along the coast of East Antarctica
(see Figures 1, 2, and 3 of the IHA application). The primary area
proposed for the study is the Totten Glacier system (preferred study
area) including the Moscow University Ice Shelf along the Sabrina
Coast, and a secondary area, the Mertz Glacier and Cook Ice Shelf,
along the Oates Coast. In addition to the planned operations of the
seismic airgun array and hydrophone streamer, NSF and ASC intend to
operate a single-beam echosounder, multi-beam echosounder, acoustic
Doppler current profiler (ADCP), and sub-bottom profiler continuously
throughout the survey. On January 3, 2014, NMFS published a notice in
the Federal Register (79 FR 464) making preliminary determinations and
proposing to issue an IHA. The notice initiated a 30-day public comment
period. On January 7, 2014, NMFS published a notice in the Federal
Register (79 FR 816) correcting the close of the public comment period
from February 3, 2014 to January 30, 2014.
Acoustic stimuli (i.e., increased underwater sound) generated
during the operation of the seismic airgun array and from icebreaking
activities have the potential to cause marine mammal behavioral
disturbance in the survey
[[Page 14220]]
area. This is the principal means of marine mammal taking associated
with these activities, and NSF and ASC have requested an authorization
to take 14 species of marine mammals by Level B harassment. Take is not
expected to result from the use of the single-beam echosounder, multi-
beam echosounder, ADCP, acoustic locator, and sub-bottom profiler, as
the brief exposure of marine mammals to one pulse, or small numbers of
signals, in this particular case is not likely to result in the
harassment of marine mammals. Also, NMFS does not expect take to result
from collision with the source vessel because it is a single vessel
moving at a relatively slow, constant cruise speed of 5 knots [kts];
9.3 kilometers per hour [km/hr]; 5.8 miles per hour [mph]) during
seismic acquisition within the survey, for a relatively short period of
time (approximately 45 operational days). It is likely that any marine
mammal will be able to avoid the vessel.
Description of the Specified Activity
NSF and ASC plan to conduct a low-energy seismic survey in the
Dumont d'Urville Sea in the Southern Ocean off the coast of East
Antarctica from January to March 2014. In addition to the low-energy
seismic survey, scientific activities will include conducting a
bathymetric profile survey of the seafloor using transducer based
instruments such as a multi-beam echosounder and sub-bottom profiler;
conducting magnetometry and imaging surveys using an underwater camera
assembly; collecting sediment cores and dredge sampling; and collecting
water samples and conductivity (salinity), temperature, depth (CTD) and
current data through the deployment and recovery of short-term (in
place for approximately one month) and long-term (in place for
approximately one year) instrumentation moorings, CTD equipment casts,
and the use of transducer-based ADCP instruments. Sea ice conditions
will dictate areas where the ship and airguns can operate. Due to
dynamic ice conditions, which cannot be predicted on a local scale, it
is not possible to develop tracklines a priori. The seismic survey will
be conducted in one or both of the two study areas depending on the sea
ice conditions; however, the preferred study area is the Totten Glacier
region (see Figure 2 of the IHA application). Water depths in the
survey area range from 100 to 1,000 meters (m) (328.1 to 3,280.1 feet
[ft]), and possibly exceeding 1,000 m in some areas. The seismic
surveys are scheduled to occur for a total of less than or equal to 300
hours at one or both of the two study areas for approximately 45
operational days in January to March 2014. The operational hours and
survey length will include equipment testing, ramp-up, line changes,
and repeat coverage. The long transit time between port and the study
site constrains how long the ship can be in the study area and
effectively limits the maximum amount of time the airguns can operate.
Some minor deviation from these dates will be possible, depending on
logistics and weather.
The planned survey of Totten Glacier and Moscow University Ice
Shelf along the Sabrina Coast continental shelf is designed to address
several critical questions. The Totten Glacier system, which drains
one-eighth of the East Antarctic Ice Sheet and contains more ice volume
than the entire West Antarctic Ice Sheet, remains the single largest
and least understood glacial system which possesses a potentially
unsteady dynamic. If it were to melt, the sea-level will rise by more
than 5 m (16.4 ft) worldwide. The planned marine studies will help to
understand both the dynamics and the controls of the Totten Glacier
system, and to resolve ambiguity in large ice mass dynamic behavior.
This research will be accomplished via the collection of glaciological,
geological, and physical oceanographic data. In order to place the
modern system, as well as more recent changes to the system, into a
longer-term perspective, researchers will collect and interpret marine
geologic, geochemical, and geophysical records of the longer term
behavior and response of this system.
The planned research will complement fieldwork studying other
Antarctic ice shelves oceanographic studies near the Antarctic
Peninsula, and ongoing development of ice sheet and other ocean models.
It will facilitate learning at sea and ashore by students, help to fill
important spatial and temporal gaps in a sparsely sampled region of
coastal Antarctica, and communicate its findings via publications and
outreach. Obtaining records of currents and oceanographic properties in
this region are consistent with the objectives of the Southern Ocean
Observing System for climate change. The work will enhance general
understanding of air-sea-ice interactions, ocean circulation, ice shelf
sensitivity to climate change, and the present and future roles of East
Antarctic Ice Sheet on sea level. The Principal Investigators are Dr.
Amy Leventer of Colgate University, Dr. Donald Blankenship and Dr. Sean
Gulick of the University of Texas at Austin, Dr. Eugene Domack of the
University of South Florida, Mr. Bruce Huber of Columbia University,
and Dr. Alejandro Orsi of Texas A&M Research Foundation.
The procedures to be used for the surveys will be similar to those
used during previous low-energy seismic surveys by NSF and will use
conventional seismic methodology. The planned survey will involve one
source vessel, the RVIB Nathaniel B. Palmer (Palmer). NSF and ASC will
deploy two (each with a discharge volume of 45 cubic inch [in\3\] with
a total volume of 90 in\3\ or each with a discharge volume of 105 in\3\
with a total volume of 210 in\3\) Sercel Generator Injector (GI) airgun
array as an energy source at a tow depth of up to 3 m (9.8 ft) below
the surface (more information on the airguns can be found in Appendix B
of the IHA application). The receiving system will consist of one 100 m
(328.1 ft) long, 24-channel, solid-state hydrophone streamer towed
behind the vessel. As the GI airguns are towed along the survey lines,
the hydrophone streamer will receive the returning acoustic signals and
transfer the data to the onboard processing system. All planned seismic
data acquisition activities will be conducted by technicians provided
by NSF and ASC with onboard assistance by the scientists who have
planned the study. The vessel will be self-contained, and the crew will
live aboard the vessel for the entire cruise.
The planned seismic survey (e.g., equipment testing, start-up, line
changes, repeat coverage of any areas, and equipment recovery) will
consist of approximately 2,800 kilometer (km) (1,511.9 nautical miles
[nmi]) of transect lines (including turns) in the survey area in the
Dumont d'Urville Sea of the Southern Ocean (see Figures 1, 2, and 3 of
the IHA application). In addition to the operation of the airgun array,
a single-beam and multi-beam echosounder, ADCP, and a sub-bottom
profiler will also likely be operated from the Palmer continuously
throughout the cruise between the first and last survey sites. There
will be additional seismic operations associated with equipment
testing, ramp-up, and possible line changes or repeat coverage of any
areas where initial data quality is sub-standard. In NSF and ASC's
estimated take calculations, 25% has been added for those additional
operations.
[[Page 14221]]
Table 1--Planned Low-Energy Seismic Survey Activities in the Dumont d'Urville Sea Off the Coast of East
Antarctica
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Time between
Survey length (km) Cumulative duration Airgun array airgun shots Streamer length (m)
(hr) \1\ total volume (Distance)
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2,800 (1,511.9 nmi)........... <=300................ 2 x 45 in\3\ (2 5 seconds....... 100 (328.1 ft).
x 737 cm\3\) or (12.5 m or 41
2 x 105 in\3\ ft).
(2 x 1,720
cm\3\).
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\1\ Airgun operations are planned for no more than 16 continuous hours at a time.
Seismic Airguns
The Palmer will deploy an airgun array, consisting of two 45 in\3\
or two 105 in\3\ GI airguns as the primary energy source and a 100 m
streamer containing hydrophones. The airgun array will have a supply
firing pressure of 2,000 pounds per square inch (psi) and 2,200 psi
when at high pressure stand-by (i.e., shut-down). The regulator is
adjusted to ensure that the maximum pressure to the GI airguns is 2,000
psi, but there are times when the GI airguns may be operated at
pressures as low as 1,750 to 1,800 psi. Seismic pulses for the GI
airguns will be emitted at intervals of approximately 5 seconds. At a
ship speed of approximately 9.3 km/hr, the shot intervals correspond to
spacing of approximately will be 12.5 m (41 ft) during the study. There
will be approximately 720 shots per hour. During firing, a brief
(approximately 0.03 second) pulse sound is emitted; the airguns will be
silent during the intervening periods. The dominant frequency
components range from two to 188 Hertz (Hz).
The GI airguns will be used in harmonic mode, that is, the volume
of the injector chamber (I) of each GI airgun is equal to that of its
generator chamber (G): 45 in\3\ and 105 in\3\ for each airgun array.
Each airgun will be initially configured to a displacement volume of 45
in\3\ for the generator and injector. The generator chamber of each GI
airgun in the primary source, the one responsible for introducing the
sound pulse into the ocean, is 45 in\3\. The injector chamber injects
air into the previously-generated bubble to maintain its shape, and
does not introduce more sound into the water. The airguns will fire the
compressed air volume in unison in a harmonic mode. In harmonic mode,
the injector volume is designed to destructively interfere with the
reverberations of the generator (source component). Firing the airguns
in harmonic mode maximizes resolution in the data and minimizes any
excess noise in the water column or data caused by the reverberations
(or bubble pulses). The two GI airguns will be spaced approximately 3
or 6 m (9.8 or 19.7 ft) apart, side-by-side, between 15 and 40 m (49.2
and 131.2 ft) behind the Palmer, at a depth of up to 3 m during the
surveys. If needed to improve penetration of the strata, the two
airguns may be reconfigured to a displacement volume of 105 in\3\ each
and will still be considered a low-energy acoustic source as defined in
the NSF/USGS PEIS. Therefore, there are three possible two airgun array
configurations: two 45/45 in\3\ airguns separated by 3 m, two 45/45
in\3\ airguns separated by 6 m, and two 105/105 in\3\ airguns separated
by 3 m. The two 45/45 in\3\ airguns separated by 3 m layout is
preferred, the two 45/45 in\3\ separated by 6 m layout will be used in
the event the middle of the three 45/45 in\3\ airgun fails, and the two
105/105 in\3\ airguns separated by 3 m will be used only if additional
penetration is needed. To summarize, two strings of GI airguns will be
available: (1) Three 45/45 in\3\ airguns on a single string where one
of these is used as a ``hot spare'' in the event of failure of one of
the other two airguns, these three GI airguns are separated by 3 m; and
(2) two 105/105 in\3\ airguns on a second string without a ``hot
spare.'' The total effective volume will be 90 or 210 in\3\. The two
strings will be spaced 14 m (45.9 ft) apart, on either side of the
midline of the vessel, however, only one string at a time will be used.
The Nucleus modeling software used at Lamont-Doherty Earth
Observatory of Columbia University (L-DEO) does not include GI airguns
as part of its airgun library, however signatures and mitigation models
have been obtained for two 45 in\3\ G airguns at 2 m tow depth and two
105 in\3\ G airguns at 3 m tow depth that are close approximations. For
the two 45 in\3\ airgun array, the source output (downward) is 230.6 dB
re: 1 [mu]Pam for 0-to-peak and 235.9 dB re: 1 [mu]Pam for peak-to-
peak. For the two 105 in\3\ airgun array, the source output (downward)
is 234.4 dB re: 1 [mu]Pam 0-to-peak and 239.8 dB re: 1 [mu]Pam for
peak-to-peak. These numbers were determined using the aforementioned G-
airgun approximation to the GI airgun and using signatures filtered
with DFS V out-256 Hz 72 dB/octave. The dominant frequency range will
be 20 to 160 Hz for a pair of GI airguns towed at 3 m depth and 35 to
230 Hz for a pair of GI airguns towed at 2 m depth.
During the low-energy seismic survey, the vessel will attempt to
maintain a constant cruise speed of approximately 5 knots. The airguns
will operate continuously for no more than 16 hours at a time and
duration of continuous operation is dependent on ice concentration. The
cumulative duration of the airgun operations will not exceed 300 hrs.
The relatively short, 24-channel hydrophone streamer will provide
operational flexibility to allow the seismic survey to proceed along
the designated cruise track with minimal interruption due to variable
sea ice conditions. The design of the seismic equipment is to achieve
high-resolution images of the glacial marine sequence stratigraphy with
the ability to correlate to the ultra-high frequency sub-bottom
profiling data and provide cross-sectional views to pair with the
seafloor bathymetry. The cruise path will be designated once in the
study area and will take care to avoid heavy ice conditions such as
icebergs or dense areas of pack ice that could potentially damage the
airguns or streamer and minimize proximity to potential marine
receptors.
Weather conditions that could affect the movement of sea ice and
hinder the hydrophone streamer will be closely monitored, as well as
conditions that could limit visibility. If situations are encountered
which pose a risk to the equipment, impede data collection, or require
the vessel to stop forward progress, the seismic survey equipment will
be shut-down and retrieved until conditions improve. In general, the
hydrophone streamer and sources could be retrieved in less than 30
minutes.
Bathymetric Survey
Along with the low-energy airgun operations, other additional
geophysical measurements will be made using swath bathymetry,
backscatter sonar imagery, high-resolution sub-bottom profiling
(``CHIRP''), imaging, and magnetometer instruments. In addition,
several other transducer-based instruments onboard
[[Page 14222]]
the vessel will be operated continuously during the cruise for
operational and navigational purposes. Operating characteristics for
the instruments to be used are described below.
Single-Beam Echosounder (Knudsen 3260)--The hull-mounted CHIRP
sonar will be operated continuously during all phases of the cruise.
This instrument is operated at 12 kHz for bottom-tracking purposes or
at 3.5 kHz in the sub-bottom profiling mode. The sonar emits energy in
a 30[deg] beam from the bottom of the ship.
Single-Beam Echosounder (Bathy 2000)--The hull-mounted sonar
characteristics of the Bathy 2000 are similar to the Knudsen 3260. Only
one hull-mounted echosounder can be operated a time, and this source
will be operated instead of the Knudsen 3260 only if needed (i.e., only
one will be in continuous operation during the cruise).
Multi-Beam Sonar (Simrad EM120)--The hull-mounted multi-beam sonar
will be operated continuously during the cruise. This instrument
operates at a frequency of 12 kHz, has an estimated maximum source
energy level of 242 dB re 1[mu]Pa (rms), and emits a very narrow
(<2[deg]) beam fore to aft and 150[deg] in cross-track. The multi-beam
system emits a series of nine consecutive 15 ms pulses.
Acoustic Doppler Current Profiler (ADCP Teledyne RDI VM-150)--The
hull-mounted ADCP will be operated continuously throughout the cruise.
The ADCP operates at a frequency of 150 kHz with an estimated acoustic
output level at the source of 223.6 dB re 1[mu]Pa (rms). Sound energy
from the ADCP is emitted as a 30[deg] conically-shaped beam. This ADCP
is also considered the sub-bottom profiler.
Acoustic Doppler Current Profiler (ADCP Ocean Surveyor OS-38)--The
characteristics of this backup hull-mounted ADCP unit are similar to
the Teledyne VM-150 and will be continuously operated.
Acoustic Locator (Pinger)--An acoustic locator (i.e., pinger) will
be deployed when using the Smith-McIntyre grab sampler and multi-corer
(Mega-corer) to enable these devices to be located in the event they
become detached from their lines. A pinger typically operates at a
frequency of 12 kHz, generates a 5 ms pulse per second, and has an
acoustical output of 162 dB re 1[mu]Pa (rms). A maximum total of 30
samples will be obtained using these devices and require approximately
one hour per sample; therefore, the pinger will operate for a total of
30 hours. Passive Instruments--During the seismic survey in the Dumont
d'Urville Sea, a precession magnetometer and Air-Sea gravity meter will
be deployed. In addition, numerous (approximately 24) expendable
bathythermograph (XBTs) probes will also be released (and none will be
recovered) over the course of the cruise to obtain temperature data
necessary to calculate sound velocity profiles used by the multi-beam
sonar.
Core and Dredge Sampling
The primary sampling goals involve the acquisition of marine
sediment cores of various lengths up to 25 m (82 ft). It is anticipated
that up to 65 sediment cores and grab samples and 12 rock dredge
samples will be collected as summarized in Table 3 (Table 3 of the IHA
application). Each core or grab sample will require approximately one
hour per sample. All cores and dredges will be deployed using a steel
cable/winch system.
Approximately 75 m\2\ (807.3 ft\2\) of seafloor will be disturbed
by each of four deployments of the dredge at three different sites
(resulting in a total of 900 m\2\ [9,687.5 ft\2\] of affected seafloor
for the project). The selection of the bottom sampling locations and
sampling method will be based on observations of the seafloor,
subsurface reflectivity, sediment type, and accessibility due to ice
and weather conditions. Bottom sampling in the Mertz Glacier area will
be limited to strategically selected locations including possible re-
sampling at a previous core site.
Table 2--Coring and Dredging Activities in the Dumont d'Urville Sea
------------------------------------------------------------------------
Sampling device Number of deployments
------------------------------------------------------------------------
Smith-MycIntyre grab sampler............. 10 to 15.
Multi-corer (Mega-corer)................. 10 to 15.
Kasten corer (regular or jumbo).......... 20 to 25.
Jumbo piston corer....................... 8 to 10.
Box cage dredge.......................... 10 to 12.
------------------------------------------------------------------------
Limited sampling of rock material will be conducted using a dredge
that will be towed along the seafloor for short distances
(approximately 50 m [164 ft]) to collect samples of bedrock and ice
rafted debris. The available dredges, which have openings of 0.5 to 1.5
m (1.6 to 4.9 ft), will be deployed on rocky substrates. The locations
of the planned dredge sites are limited to the inner shelf (southern)
perimeter of three areas: The Mertz Trough and two regions along the
Sabrina Coast. Final selection of dredge sites will include review to
ensure that the seamounts or corals in the area are avoided (AOA,
2011).
The Commission for the Conservation of Antarctic Marine Living
Resources (CCAMLR) has adopted conservation measures (i.e., 22-06, 22-
07, and 22-09) to protect vulnerable marine ecosystems (VME), which
include seamounts, hydrothermal vents, cold water corals, and sponge
fields. The conservation measure 22-07 includes mitigation and
reporting requirements if VME are encountered. The science team will
follow these requirements (see Attachment C of the IHA application) if
VME's are encountered while sampling the sea bottom.
In addition, a camera and towed video system will be deployed at up
to 25 sites. This device will lightly touch the seafloor to establish a
baseline and rise to an optimum elevation to obtain the desired images.
Water Sampling and Current Measurements
High-resolution conductivity, depth, and temperature (CTD)
measurements will be collected to characterize the summer regional
water mass stratification and circulation, and the meridional exchange
of waters between the oceanic and shelf regimes. These physical
measurements will involve approximately SeaBird CTD system casts
including the use of a lowered ADCP (LADCP).
The LADCP will consist of two Teledyne RDI Workhorse Monitor ADCPs
mounted on the CTD/rosette frame and one oriented upward and the other
downward. The LADCP and frame will be raised and lowered by cable and
winch. The LADCPs will operate at a frequency of 307.2 kHz, with an
estimated output acoustic pressure along each 4 beams of 216.3 dB re
1[mu]Pa at 1 m. The beams are angled at 20 degrees from the centerline
of the ADCP head, with a beam angle of 4 degrees for the individual
beams. Typical pulse duration is 5.7 ms, with a typical repetition rate
of 1.75 s. The upward and downward-looking ADCPs are operated in
master-salve mode so that only one head pings at a time. The LADCP will
be operated approximately one hour at every CTD/rosette station
(maximum of 100 stations) for a total of 100 hours of operation.
These instruments will be used to profile the full water column for
temperature, salinity (conductivity), dissolved oxygen and currents at
a series of transects in the study area. Discrete water samples will be
collected for salinity and dissolved oxygen to monitor CTD/rosette
performance, and for oxygen isotopes to assess meltwater content. Water
samples will also be collected for development and interpretation of
marine sediment proxies using Niskin bottles.
[[Page 14223]]
Observations of the thermal structure along other portions of the
cruise track will be made using an underway CTD system and XBTs while
the seafloor is swath-mapped. The number and spacing of stations will
be adjusted according to ocean features discovered through multi-beam
swath mapping and the sea ice conditions. If portions of the study area
are inaccessible to the NBP, a contingency sampling focused on the
inflows of MDCW will be pursued in adjacent shelf troughs.
It is noted that underway ADCP on the Palmer can, under ideal
conditions, obtain profiles of ocean currents to depths greater than
800 m (2,624.7 ft). On continental shelves where depths may be less
than the range of the ADCP, the underway profiles cannot resolve the
deepest 15% of the water column due to side lobe reflections from the
bottom which contaminate the water column Doppler returns. For a depth
of 800 m, expected in the MCDW, currents in the lower 120 m (393.7 ft)
could not be measured by the ship ADCP; therefore, the lowered ADCP can
provide accurate current profiles to within a few meters of the bottom
and provide complete coverage of the velocity field at each CTD
station.
Instrumentation Moorings
Four instrumented moorings will be deployed during the cruise to
measure current, temperature, and salinity (conductivity) continuously.
Two of the moorings will be deployed for approximately one month
(short-term moorings) and two moorings will be deployed for
approximately one year (long-term moorings). The two short-term
moorings and one long-term mooring will include ADCP paired with CTD
recorders, and additional intermediate T (i.e., temperature) recorders.
The characteristics of the ADCP units deployed on the moorings are
similar to the Teledyne VM-150; the moored ADCPs operate at frequencies
of 75 kHz (one unit) and 300 kHz (two units). The fourth mooring will
be equipped with sediment traps, a CTD recorder and intermediate T
recorders, and be deployed for approximately one year (long-term
mooring). The two long-term moorings will be retrieved approximately
one year later by a U.S. Arctic Program (USAP) vessel or collaborators
from other countries.
Subject to sea ice conditions, these moorings will preferably be
placed in front of Totten Glacier, but otherwise as close as possible
inside adjacent cross-shelf troughs. If access to the inner shelf is
not allowed by sea ice conditions, mooring deployments will be
attempted within the outer shelf close to the troughs mouth, where the
Totten Glacier is more directly connected to inflows from the oceanic
domain offshore. The two long-term moorings will be deployed within 16
km of each other. The short-term moorings will be within a few
kilometers of each other and no farther than 32 km (17.3 nmi) from the
long-term moorings. All instruments will be kept at depths below 250 m
(820.2 ft) to minimize damage or loss by icebergs.
The moorings will be temporarily attached to anchors and be
recovered using acoustic release mechanisms. The mooring recovery
process will be similar regardless of mooring type or when they will be
retrieved. Locating the moorings and releasing the moorings from the
steel railroad wheel anchors (which will not be recovered) will be
accomplished by transmitting sound over a period of several seconds.
This is done with an acoustic deck command unit that sends a sequence
of coded pulses to the receiving units, the acoustic releases,
connected to the mooring anchors. The acoustic releases response to
acknowledge the receipt of commands from the deck unit is by
transmitting a short sequence of pulses back. Both of the acoustic
units (onboard deck unit and moored releases) operate at frequencies
between approximately 7 and 15 kHz. The beam pattern is approximately
omnidirectional. The acoustic source level is less than 192 dB re
1[mu]Pa at 1 m.
In addition to the U.S. moorings described above, three new
moorings will be deployed on behalf of Australia's national science
agency the Commonwealth of Scientific and Industrial Research
Organisation (CSIRO) Physical Oceanography group in the Totten Glacier
region by the project team. These moorings will be retrieved
approximately one year later by collaborators from other countries.
Also, during this cruise, three CSIRO moorings that were deployed over
a year ago in the western outlet of the Mertz-Ninnis Trough will be
recovered. The recovery process and acoustic sources described above
for the U.S. moorings will be used for recovery of the CSIRO moorings.
Icebreaking
Icebreaking is considered by NMFS to be a continuous sound and NMFS
estimates that harassment occurs when marine mammals are exposed to
continuous sounds at a received sound level of 120 dB SPL or above. The
Palmer operates at approximately 3 kts in pack ice and can operate in
pack ice up to 0.9 m (3 ft) thick. Potential takes of marine mammals
may ensue from icebreaking activity in which the Palmer is expected to
engage in Antarctic waters (i.e., along the George V and Oates Coast of
East Antarctica, >65[deg] South, between 140 and 165[deg] East and
between approximately 65 to 66[deg] South and between 95 to 135[deg]
East). While breaking ice, the noise from the ship, including impact
with ice, engine noise, and propeller cavitation, will exceed 120 dB
(rms) continuously. If icebreaking does occur in Antarctic waters,
NMFS, NSF and ASC expect it will occur during transit and non-seismic
operations to gain access to coring, dredging, or other sampling
locations and not during seismic airgun operations. The research
activities and associated contingencies are designed to avoid areas of
heavy sea ice condition. The buffer zone (160 dB [rms]) for the marine
mammal Level B harassment threshold during the planned airgun
activities is much smaller than the calculated radius during
icebreaking. If the Palmer breaks ice during the survey within the
Antarctic waters (within the Dumont d'Urville Sea or other areas of the
Southern Ocean), seismic airgun operations will not be conducted
concurrently.
In 2008, acousticians from Scripps Institution of Oceanography
Marine Physical Laboratory and University of New Hampshire Center for
Coastal and Ocean Mapping conducted measurements of SPLs of the Healy
icebreaking under various conditions (Roth and Schmidt, 2010). The
results indicated that the highest mean SPL (185 dB) was measured at
survey speeds of 4 to 4.5 kts in conditions of 5/10 ice and greater.
Mean SPL under conditions where the ship was breaking heavy ice by
backing and ramming was actually lower (180 dB). In addition, when
backing and ramming, the vessel is essentially stationary, so the
ensonified area is limited for a short period (on the order of minutes
to tens of minutes) to the immediate vicinity of the vessel until the
ship breaks free and once again makes headway.
The 120 dB received sound level radius around the Healy while
icebreaking was estimated by researchers (USGS, 2010). Using a
practical spreading model, a source level of 185 dB decays to 120 dB in
about 21,544 m (70,684 ft). (Note: The proposed IHA used a spherical
spreading model that predicted a distance of 1,750 m to 120 dB in deep
water depths [greater than 1,000 m], this model was corroborated by
Roth and Schmidt [2010]. A practical spreading model is now being used
since the planned survey is occurring in
[[Page 14224]]
intermediate water depths [between 100 and 1,000 m].). Therefore, as
the ship travels through the ice, a swath 21.54 km (11.63 nmi) wide may
be subject to sound levels greater than or equal to 120 dB. This
results in potential exposure of 21,540 km\2\ (6,380.1 nmi\2\) to
sounds greater than or equal to 120 dB from icebreaking.
Data characterizing the sound levels generated by icebreaking
activities conducted by the Palmer are not available; therefore, data
for noise generating from an icebreaking vessel such as the U.S. Coast
Guard Cutter (USCGC) Healy will be used as a proxy. It is noted that
the Palmer is a smaller vessel and has less icebreaking capability than
the U.S. Coast Guard's other polar icebreakers, being only capable of
breaking ice up to 1 m thick at speeds of 3 kts (5.6 km/hr or 3 nmi).
Therefore, the sound levels that may be generated by the Palmer are
expected to be lower than the conservative levels estimated and
measured for the Healy. Researchers will work to minimize time spent
breaking ice as science operations are more difficult to conduct in icy
conditions since the ice noise degrades the quality of the seismic and
ADCP data and time spent breaking ice takes away from time supporting
scientific research. Logistically, if the vessel were in heavy ice
conditions, researchers will not tow the airgun array and streamer, as
this will likely damage equipment and generate noisy data. It is
possible that the seismic survey can be performed in low ice conditions
if the Palmer could generate an open path behind the vessel.
Because the Palmer is not rated to break multi-year ice routinely,
operations generally avoid transiting through older ice (i.e., 2 years
or older, thicker than 1 m). If sea ice is encountered during the
cruise, it is anticipated the Palmer will proceed primarily through one
year sea ice, and possibly some new, very thin ice, and will follow
leads wherever possible. Satellite imagery from the Totten region
documents that sea ice is at its minimum extent during the month of
February. A recent image for the region, from November 21, 2013, shows
that the sea ice is currently breaking up, with a significant coastal
lead of open water. Based on a maximum sea ice extent of 250 km (135
nmi) and estimating that NSF and ASC will transit to the innermost
shelf and back into open water twice, a round trip transit in each of
the potential work regions, NSF and ASC estimate that the Palmer will
actively break ice up to a distance of 1,000 km (540 nmi). Based on a
ship's speed of 5 kts under moderate ice conditions, this distance
represents approximately 108 hrs of icebreaking operations. It is noted
that typical transit through areas primarily open water and containing
brash ice or pancake ice will not be considered icebreaking.
Dates, Duration, and Specified Geographic Region
The planned project and survey sites are located in selected
regions of the Dumont d'Urville Sea in the Southern Ocean off the coast
of East Antarctica and focus on the Totten Glacier and Moscow
University Ice Shelf, located on the Sabrina Coast, from greater than
approximately 64[deg] South and between approximately 95 to 135[deg]
East (see Figure 2 of the IHA application), and the Mertz Glacier and
Cook Ice Shelf systems located on the George V and Oates Coast, from
greater than approximately 65[deg] South and between approximately 140
to 165[deg] East in International Waters. The planned study sites are
characterized by heavy ice cover, with a seasonal break-up in the ice
that structures biological patterns. The planned studies will occur in
both areas, or entirely in one or the other, depending on ice
conditions. Figure 3 of the IHA application illustrates the limited
detailed bathymetry of the two study areas. Ice conditions encountered
during the previous surveys in the region limited the area where
bathymetric data could be collected. Water depths in the survey area
range from approximately 100 to 1,000 m, and possibly exceeding 1,000 m
in some areas. There is limited information on the depths in the study
area and therefore more detailed information on bathymetry is not
available. Figures 2 and 3 of the IHA application illustrate the
limited available detailed bathymetry of the two planned study areas
due to ice conditions encountered during previous surveys in the
region. The planned seismic survey will be within an area of
approximately 5,628 km\2\ (1,640.9 nmi\2\). This estimate is based on
the maximum number of kilometers for the seismic survey (2,800 km)
times the predicted rms radii (m) based on modeling and empirical
measurements (assuming 100% use of the two 105 in\3\ GI airguns in 100
to 1,000 m water depths) which was calculated to be 1,005 m (3,297.2
ft) (multiplied by two to calculate the diameter of the buffer zone).
The icebreaking will occur, as necessary, between approximately 66
to 70[deg] South and between 140 to 165[deg] East and between
approximately 65 to 66[deg] South and between 95 to 135[deg] East. The
total distance in the region of the vessel will travel include the
seismic survey and transit to dredging or sampling locations and will
represent approximately 5,600 km (3,023.8 nmi). Based on a maximum sea
ice extent of 250 km (135 nmi) and estimating that NSF and ASC will
transit to the innermost shelf and back into open water twice, a round
trip transit in each of the potential work regions, NSF and ASC
estimate that the Palmer will actively break ice up to a distance of
1,000 km (540 nmi). Based on a ship's speed of 5 kts under moderate ice
conditions, this distance represents approximately 108 hrs of
icebreaking operations.
The Palmer is expected to depart from Hobart, Tasmania on
approximately January 29, 2014 and return to Hobart, Tasmania on
approximately March 16, 2014. Research operations will be over a span
of 45-days, including to and from port. Ice-free or very low
concentrations of sea ice are required in order to collect high quality
seismic data and not impede passage of the vessel between sampling
locations. This requirement restricts the cruise to operating in mid to
late austral summer when the ice concentrations are typically the
lowest. Some minor deviation from this schedule is possible, depending
on logistics and weather (i.e., the cruise may depart earlier or be
extended due to poor weather; there could be additional days of seismic
operations if collected data are deemed to be of substandard quality).
NMFS outlined the purpose of the program in a previous notice for
the proposed IHA (79 FR 464, January 3, 2014). The activities to be
conducted have not changed between the proposed IHA notice and this
final notice announcing the issuance of the IHA. For a more detailed
description of the authorized action, including vessel and acoustic
source specifications, metrics, characteristics of airgun pulses,
predicted sound levels of airguns, etc., the reader should refer to the
notice of the proposed IHA (79 FR 464, January 3, 2014), the IHA
application, IEE/EA, and associated documents referenced above this
section.
Comments and Responses
A notice of the proposed IHA for the NSF and ASC low-energy seismic
survey was published in the Federal Register on January 3, 2014 (79 FR
464). During the 30-day public comment period, NMFS received comments
from the Marine Mammal Commission (Commission) and one private citizen.
The comments are online at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm. Following are the
[[Page 14225]]
substantive comments and NMFS's responses:
Comment 1: The Commission recommends that NMFS require NSF and ASC
to re-estimate the proposed exclusion and buffer zones and associated
takes of marine mammals using site-specific parameters (including at
least sound speed profiles, bathymetry, and sediment characteristics)
for the proposed IHA--NMFS should make the same requirement for all
future IHAs submitted by NSF, ASC, L-DEO, U.S. Geological Survey
(USGS), Scripps Institution of Oceanography (SIO), or any other related
entity.
Response: NMFS acknowledges the Commission's concerns about L-DEO's
current model for estimating exclusion and buffer zones. We also
acknowledge L-DEO did not incorporate site-specific sound speed
profiles, bathymetry, and sediment characteristics of the research area
into their current model to estimate those zones for this IHA.
During a March 2013 meeting, L-DEO discussed the L-DEO model with
the Commission, NMFS, and NSF. L-DEO compared the Gulf of Mexico (GOM)
calibration measurements (Tolstoy et al., 2004; Tolstoy et al., 2009;
Diebold et al., 2010) comparison with L-DEO model results, and
explained correction factors used in previous EAs to adapt the deep-
water model results for intermediate water depth environment. L-DEO
showed that at the calibration sites the model overestimated the size
of the exclusion zones and, therefore, is likely precautionary in most
cases. Based on the best available information that the current model
overestimates mitigation zones, we will not require L-DEO to re-
estimate the proposed buffer and exclusion zones and associated number
of marine mammal takes using operational and site-specific
environmental parameters for this IHA.
However, we continue to work with the NSF and L-DEO on verifying
the accuracy of their model. L-DEO is currently analyzing whether
received levels can be measured in real-time using the ship's
hydrophone streamer to estimate the sound field around the ship and
determine actual distances to the buffer and exclusion zones. Crone et
al. (2013) are analyzing R/V Marcus G. Langseth streamer data collected
in 2012 off the Washington coast shelf and slope to measure received
levels in situ up to 8 km (4.3 nmi) away from the ship. While results
confirm the role that bathymetry plays in propagation, it also
confirmed that empirical measurements from the GOM survey used to
inform buffer and exclusion zones in shallow water and model results
adapted for intermediate water depths also over-estimated the size of
the zones for the Washington survey. Preliminary results were presented
in a poster session at the American Geophysical Union fall meeting in
December 2013 (Crone et al., 2013; available at: http://berna.ldeo.columbia.edu/agu2013/agu2013.pdf) and a peer-reviewed
journal publication is anticipated in 2014. When available, we will
review and consider the final results and how they reflect on the L-DEO
model.
Comment 2: The Commission recommends that NMFS (1) require NSF and
ASC to revise its take estimates to include Level B harassment takes
associated with the use of the single-beam and multi-beam echosounder
when the airgun array is not firing and (2) follow a consistent
approach of requiring the assessment of Level B harassment takes for
those types of sound sources (e.g., sub-bottom profilers, echosounders,
side-scan sonar, and fish-finding sonar) by all applicants, who propose
to use such sources.
Response: As described in NSF's application and the NSF/USGS PEIS
(2011), they expect the sound levels produced by the single-beam and
multi-beam echosounder, ADCP, sub-bottom profiler sound sources to be
exceeded by the sound levels produced by the airguns for the majority
of the time. Additionally, because of the beam pattern and
directionality of these sources, combined with their lower source
levels, it is far less likely that these sources (which are used in
some capacity by the vast majority of vessels on the water) will take
marine mammals independently from the takes that have already been
estimated for the airguns. Therefore, NMFS does not believe it is
necessary to authorize additional takes for these sources for the
action. Nonetheless, NMFS is currently evaluating the broader use of
these types of sources to determine under what specific circumstances
coverage for incidental take would be advisable (or not) and is working
on guidance that would outline a consistent recommended approach (to be
used by applicants and NMFS) for addressing the potential impacts of
these types of sources.
Comment 3: The Commission recommends that NMFS require NSF and ASC
to estimate the numbers of marine mammals taken when the single-beam
and multi-beam echosounder are used in the absence of the airgun array
based on the 120 rather than 160 dB re: 1 [mu]Pa (rms) threshold.
Response: NMFS disagrees with the Commission's recommendation that
NMFS require NSF and ASC to estimate the number of marine mammals taken
when the single-beam and multi-beam echosounder, ADCP, and sub-bottom
profiler are used in absence of the airgun array based on the 120 dB
(rms) threshold rather than the 160 dB (rms) threshold. 160 dB (rms) is
the appropriate threshold for these sound sources. Continuous sounds
are those whose sound pressure level remains above that of the ambient
sound, with negligibly small fluctuations in level (NIOSH, 1998; ANSI,
2005), while intermittent sounds are defined as sounds with interrupted
levels of low or no sound (NIOSH, 1998). Thus, echosounder signals are
not continuous sounds but rather intermittent sounds. Intermittent
sounds can further be defined as either impulsive or non-impulsive.
Impulsive sounds have been defined as sounds which are typically
transient, brief (less than 1 second), broadband, and consist of a high
peak pressure with rapid rise time and rapid decay (ANSI, 1986; NIOSH,
1998). Echosounder signals also have durations that are typically very
brief (less than 1 second), with temporal characteristics that more
closely resemble those of impulsive sounds than non-impulsive sounds,
which typically have more gradual rise times and longer decays (ANSI,
1995; NIOSH, 1998). With regard to behavioral thresholds, we therefore
consider the temporal and spectral characteristics of echosounder
signals to more closely resemble those of an impulsive sound than a
continuous sound.
The Commission suggests that, for certain sources considered here,
the interval between pulses would not be discernible to the animal,
thus rendering them effectively continuous. However, an echosounder's
``rapid staccato'' of pulse trains is emitted in a similar fashion as
odontocete echolocation click trains. Research indicates that marine
mammals, in general, have extremely fine auditory temporal resolution
and can detect each signal separately (e.g., Au et al., 1988; Dolphin
et al., 1995; Supin and Popov, 1995; Mooney et al., 2009), especially
for species with echolocation capabilities. Therefore, it is highly
unlikely that marine mammals would perceive echosounder signals as
being continuous.
In conclusion, echosounder, ADCP, and sub-bottom profiler signals
are intermittent rather than continuous signals, and the fine temporal
resolution of the marine mammal auditory system allows them to perceive
these sounds as such. Further, the physical characteristics of these
signals indicate a greater similarity to the way that
[[Page 14226]]
intermittent, impulsive sounds are received. Therefore, the 160 dB
threshold (typically associated with impulsive sources) is more
appropriate than the 120 dB threshold (typically associated with
continuous sources) for estimating takes by behavioral harassment
incidental to use of such sources.
Comment 4: The Commission recommends that NMFS consult with experts
in the field of acoustics and marine mammal hearing to revise the Level
B harassment thresholds for behavior to specify threshold levels that
would be more appropriate for a wider range of sound sources, including
shallow penetration sub-bottom profilers, echosounders, and side-scan
sonars--if NMFS plans to propose behavior thresholds for seismic
surveys separate from other activities, include thresholds for all
types of sources that are used, not just for airguns.
Response: NMFS agrees with the Commission's recommendation to
revise existing acoustic criteria and thresholds as necessary to
specify threshold levels that would be more appropriate for a wider
range of sound sources, and are currently in process of producing such
revisions. In particular, NMFS recognizes the importance of context
(e.g., behavioral state of animals, distance) in behavioral responses.
The current behavioral categorization (i.e., impulse versus continuous)
does not account for context and is not appropriate for all sound
sources. Thus, updated NOAA Acoustic Guidance http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm) will more appropriately categorize
behavioral harassment criteria by activity type.
Comment 5: The Commission recommends that NMFS consult with the
funding agency (i.e., NSF) and individual applicants (e.g., ASC, L-DEO,
SIO, USGS, etc.) to develop, validate, and implement a monitoring
program that provides a scientifically sound, reasonably accurate
assessment of the types of marine mammal takes and the actual numbers
of marine mammals taken--the assessment should account for applicable
g(0) and f(0) values.
Response: There will be periods of transit time during the cruise,
and PSOs will be on watch prior to and after the seismic airgun
operations and icebreaking portions of the surveys, in addition to
during the surveys. The collection of this visual observational data by
PSOs may contribute to baseline data on marine mammals (presence/
absence) and provide some generalized support for estimated take
numbers (as well as providing data regarding behavioral responses to
seismic operation that are observable at the surface), but is unlikely
that the information gathered from these cruises alone would result in
any statistically robust conclusions for any particular species because
of the small number of animals typically observed.
NMFS is currently working to develop recommendations for how
applicants can appropriately correct marine mammal detections to better
estimate the number of animals likely taken during specified
activities, in consideration of those that are not detected.
Comment 6: The Commission recommends that NMFS (1) provide a full
30-day public review and comment period that starts with the
publication of notices in the printed edition of the Federal Register
and (2) allow sufficient time after the close of the comment period and
prior to issuance of an IHA to allow the agency to analyze, consider,
respond to, and make any necessary changes to the proposed
authorization of NMFS's rationale based on those comments.
Response: Section 101(a)(5)(D) of the MMPA establishes a 30-day
public notice and comment period on any proposed authorizations for the
incidental harassment of small numbers of marine mammals. NMFS's
standard procedure is to have a 30-day public comment period that
extends from publication in the Federal Register to the closure date
specified in the notice of the proposed IHA (with an additional 2 days
for those that check the electronic version available online). The
public was afforded a 30-day comment period to review and submit
information and suggestions on the proposed IHA with the electronic
availability of the notice of proposed IHA and making preliminary
determinations available on the Federal Register's Web site on December
31, 2013. On January 3, 2014, NMFS published the notice in the Federal
Register (79 FR 464). On January 7, 2014, NMFS published a notice in
the Federal Register correcting the dates in the issue of Friday,
January 3, 2014 ``. . . on page 464, in the first column, in the 41st
through 42nd lines, `February 3, 2014 should read `January 30, 2014''
(79 FR 816). NMFS fully intends to have a 30-day public comment period
on all future notices of proposed IHA published in the Federal
Register, but in this particular case operational needs supported the
use of a 30-day public comment period from electronic filing to closure
in order to ensure that NMFS had adequate time to address public
comments before making a decision of whether to issue an IHA to NSF and
ASC in time for the needed start date of the seismic survey.
NMFS has been issuing MMPA authorizations to NSF to conduct these
activities for approximately 10 years, which has allowed NMFS to
develop relatively standard mitigation and monitoring requirements for
these activities, so rarely more than one or two public comments are
received. NMFS received only comments from the Commission and a private
citizen during the 30-day public review and comment period. NMFS
believes it has sufficient time after the close of the comment period
and prior to issuance of an IHA to allow the agency to analyze,
consider, respond to, and make any necessary changes to the proposed
IHA of the rationale based on those comments.
Comment 7: An individual opposes the issuance of the IHA to NSF and
ASC, who also states that NSF and ASC's project is killing marine
mammals.
Response: As described in detail in the Federal Register notice for
the proposed IHA (79 FR 464, January 3, 2014), as well as in this
document, NMFS determined that NSF and ASC's low-energy seismic survey
will not cause injury, serious injury, or mortality to marine mammals.
The required monitoring and mitigation measures that NSF and ASC will
implement during the low-energy seismic survey will further reduce the
adverse effects on marine mammals to the lowest levels practicable.
NMFS anticipates only behavioral disturbance to occur during the
conduct of the low-energy seismic survey.
Description of the Marine Mammals in the Specified Geographic Area of
the Specified Activity
The marine mammals that generally occur in the planned action area
belong to three taxonomic groups: mysticetes (baleen whales),
odontocetes (toothed whales), and pinnipeds (seals and sea lions). The
marine mammal species that potentially occur within the Southern Ocean
in proximity to the action area in the Dumont d'Urville Sea include 28
species of cetaceans and 6 species of pinnipeds.
The Dumont d'Urville Sea may be a feeding ground for many of these
marine mammals. Many of the species that may be potentially present in
the study area seasonally migrate to higher latitudes along the east
coast of Antarctica. In general, most species (except for the killer
whale) migrate north in the middle of the austral winter and return to
Antarctica in the early austral
[[Page 14227]]
summer. Some species, particularly Antarctic minke (Balaenoptera
bonaerensis) and killer whales (Orcinus orca), are expected to be
present in higher concentrations along the ice edge (SCAR, 2002). The 6
species of pinnipeds that are found in the Southern Ocean and which may
be present in the planned study area include the crabeater (Lebodon
carcinophagus), leopard (Hydrurga leptonyx), Weddell (Leptonychotes
weddellii), Ross (Ommatophoca rossii), southern elephant (Mirounga
leonina), and Antarctic fur seal (Arctocephalus gazella). Many of these
pinniped species breed on either the pack ice or sub-Antarctic islands.
Since the southern elephant seal and Antarctic fur seal haul-outs and
rookeries are located on sub-Antarctic islands and prefer beaches, they
are more common north of the seasonally shifting pack ice found in the
study area; therefore, these two species have not been considered
further. Marine mammal species listed as endangered under the U.S.
Endangered Species Act of 1973 (ESA; 16 U.S.C. 1531 et seq.), include
the southern right (Eubalaena australis), humpback (Megaptera
novaeangliae), sei (Balaenoptera borealis), fin (Balaenoptera
physalus), blue (Balaenoptera musculus), and sperm (Physeter
macrocephalus) whale. Of those endangered species, the humpback, sei,
fin, blue, and sperm whale are likely to be encountered in the survey
area.
Various national Antarctic research programs along the coast of
East Antarctica have conducted scientific cruises that included data on
marine mammal sightings. These observations were made primarily between
30deg; East and 170[deg] East and north to 60[deg] South. The reported
cetacean sightings are summarized in Tables 5 to 7 of the IHA
application. For pinnipeds, observations made during a scientific
cruise over a 13-day period in East Antarctica are summarized in Table
9 of the IHA application. These observations were made below 60[deg]
South and between 110[deg] East to 165[deg] East and include sightings
of individual animals in the water as well as individuals that were
hauled-out (i.e., resting on the surface of the sea ice).
Records from the International Whaling Commission's Southern Ocean
Whale and Ecosystem Research (IWC-SOWER) circumpolar cruises were also
considered. In addition to the 14 species known to occur in the Dumont
d'Urville Sea of the Southern Ocean, there are 18 cetacean species with
ranges that are known to occur in the sub-Antarctic waters of the study
area which may also feed and/or migrate to the Southern Ocean during
the austral summer, these include the southern right, pygmy right
(Caperea marginata), Bryde's (Balaenoptera brydei), dwarf minke
(Balaenoptera acutorostrata spp.), pygmy blue (Balaenoptera musculus
brevicauda), pygmy dwarf sperm whale (Kogia breviceps), Arnoux's beaked
(Berardius arnuxii), Blainville's beaked whale (Mesoplodon
densirostris), Cuvier's beaked (Ziphius cavirostris), Shepherd's beaked
(Tasmacetus shepherdi), Southern bottlenose (Hyperoodon planifrons),
Andrew's beaked (Mesoplodon bowdoini), Hector's beaked (Mesoplodon
hectori), Gray's beaked (Mesoplodon grayi), strap-toothed beaked
(Mesoplodon layardii), spade-toothed beaked (Mesoplodon traversii),
southern right whale dolphin (Lissodelphis peronii), Dusky
(Lagenorhynchus obscurus), and bottlenose dolphin (Tursiops truncatus).
However, these species have not been sighted and are not expected to
occur where the planned activities will take place. These species are
not considered further in this document. Table 3 (below) presents
information on the abundance, distribution, population status,
conservation status, and population trend of the species of marine
mammals that may occur in the planned study area during January to
March 2014.
Table 3--The Habitat, Regional Abundance, and Conservation Status of Marine Mammals That May Occur In Or Near
the Low-Energy Seismic Survey Area In the Antarctic Area of the Southern Ocean
[See Text and Tables 4 In NSF and ASC's Application For Further Details]
----------------------------------------------------------------------------------------------------------------
Population
Species Habitat estimate ESA \1\ MMPA \2\ Population trend
----------------------------------------------------------------------------------------------------------------
Mysticetes:
Southern right whale Coastal, pelagic. 8,000 \3\ to EN........ D........... Increasing.
(Eubalaena australis). 15,000 \4\.
Pygmy right whale (Caperea Coastal, pelagic. NA............... NL........ NC.......... NA.
marginata).
Humpback whale (Megaptera Pelagic, 35,000 to 40,000 EN........ D........... Increasing.
novaeangliae). nearshore \3\--Worldwide
waters, and 9,484 \5\--
banks. Scotia Sea and
Antarctica
Peninsula.
Dwarf minke whale Pelagic and NA............... NL........ NC.......... NA.
(Balaenoptera coastal.
acutorostrata sub-
species).
Antarctic minke whale Pelagic, ice Several 100,000 NL........ NC.......... Stable.
(Balaenoptera floes. \3\--Worldwide
bonaerensis). 18,125 \5\--
Scotia Sea and
Antarctica
Peninsula.
Bryde's whale Pelagic and NA............... NL........ NC.......... NA.
(Balaenoptera brydei). coastal.
Sei whale (Balaenoptera Primarily 80,000 \3\-- EN........ D........... NA.
borealis). offshore, Worldwide.
pelagic.
Fin whale (Balaenoptera Continental 140,000 \3\-- EN........ D........... NA.
physalus). slope, pelagic. Worldwide 4,672
\5\--Scotia Sea
and Antarctica
Peninsula.
Blue whale (Balaenoptera Pelagic, shelf, 8,000 to 9,000 EN........ D........... NA.
musculus). coastal. \3\--Worldwide
1,700 \6\--
Southern Ocean.
Odontocetes:
Sperm whale (Physeter Pelagic, deep sea 360,000 \3\-- EN........ D........... NA.
macrocephalus). Worldwide 9,500
\3\--Antarctic.
Pygmy sperm whale (Kogia Pelagic, slope... NA............... NL........ NC.......... NA.
breviceps).
Arnoux's beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Berardius arnuxii).
[[Page 14228]]
Blainville's beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Mesoplodon densirostris).
Cuvier's beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Ziphius cavirostris).
Shepherd's beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Tasmacetus shepherdi).
Southern bottlenose whale Pelagic.......... 500,000 \3\-- NL........ NC.......... NA.
(Hyperoodon planifrons). South of
Antarctic
Convergence.
Andrew's beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Mesoplodon bowdoini).
Hector's beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Mesoplodon hectori).
Gray's beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Mesoplodon grayi).
Strap-toothed beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Mesoplodon layardii).
Spade-toothed beaked whale Pelagic.......... NA............... NL........ NC.......... NA.
(Mesoplodon traversii).
Killer whale (Orcinus Pelagic, shelf, 80,000 \3\--South NL........ NC.......... NA.
orca). coastal, pack of Antarctic
ice. Convergence
25,000 \7\--
Southern Ocean.
Long-finned pilot whale Pelagic, shelf, 200,000 3 8-- NL........ NC.......... NA.
(Globicephala melas). coastal. South of
Antarctic
Convergence.
Bottlenose dolphin Offshore, >625,500 \3\-- NL........ NC.......... NA.
(Tursiops truncatus). inshore, Worldwide.
coastal,
estuaries.
Southern right whale Pelagic.......... NA............... NL........ NC.......... NA.
dolphin (Lissodelphis
peronii).
Dusky dolphin Coastal, NA............... NL........ NC.......... NA.
(Lagenorhynchus obscurus). continental
shelf and slope.
Hourglass dolphin Pelagic, ice edge 144,000 \3\...... NL........ NC.......... NA.
(Lagenorhynchus cruciger).
Spectacled porpoise Coastal, pelagic. NA............... NL........ NC.......... NA.
(Phocoena dioptrica).
Pinnipeds:
Crabeater seal (Lobodon Coastal, pack ice 5,000,000 to NL........ NC.......... Increasing.
carcinophaga). 15,000,000 3 9.
Leopard seal (Hydrurga Pack ice, sub- 220,000 to NL........ NC.......... NA.
leptonyx). Antarctic 440,000 3 10.
islands.
Ross seal (Ommatophoca Pack ice, smooth 130,000 \3\...... NL........ NC.......... NA.
rossii). ice floes,
pelagic.
Weddell seal Fast ice, pack 500,000 to NL........ NC.......... NA.
(Leptonychotes weddellii). ice, sub- 1,000,000 3 11.
Antarctic
islands.
Southern elephant seal Coastal, pelagic, 640,000 \12\ to NL........ NC.......... Decreasing,
(Mirounga leonina). sub-Antarctic 650,000 \3\. increasing or
waters. stable
depending on
breeding
population.
Antarctic fur seal Shelf, rocky 1,600,000 \13\ to NL........ NC.......... Increasing.
(Arctocephalus gazella). habitats. 3,000,000 \3\.
----------------------------------------------------------------------------------------------------------------
NA = Not available or not assessed.
\1\ U.S. Endangered Species Act: EN = Endangered, T = Threatened, DL = Delisted, NL = Not listed.
\2\ U.S. Marine Mammal Protection Act: D = Depleted, S = Strategic, NC = Not Classified.
\3\ Jefferson et al., 2008.
\4\ Kenney, 2009.
\5\ Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) survey area (Reilly et al.,
2004).
\6\ Sears and Perrin, 2009.
\7\ Ford, 2009.
\8\ Olson, 2009.
\9\ Bengston, 2009.
\10\ Rogers, 2009.
\11\ Thomas and Terhune, 2009.
\12\ Hindell and Perrin, 2009.
\13\ Arnould, 2009.
Refer to sections 3 and 4 of NSF and ASC's IHA application for
detailed information regarding the abundance and distribution,
population status, and life history and behavior of these other marine
mammal species and their occurrence in the project area. The IHA
application also presents how NSF and ASC calculated the estimated
densities for the marine mammals in the survey area. NMFS has reviewed
these data and determined them to be the best available scientific
information for the purposes of the IHA.
[[Page 14229]]
Potential Effects on Marine Mammals
Acoustic stimuli generated by the operation of the airguns, which
introduce sound into the marine environment, may have the potential to
cause Level B harassment of marine mammals in the planned survey area.
The effects of sounds from airgun operations might include one or more
of the following: Tolerance, masking of natural sounds, behavioral
disturbance, temporary or permanent hearing impairment, or non-auditory
physical or physiological effects (Richardson et al., 1995; Gordon et
al., 2004; Nowacek et al., 2007; Southall et al., 2007). Permanent
hearing impairment, in the unlikely event that it occurred, would
constitute injury, but temporary threshold shift (TTS) is not an injury
(Southall et al., 2007). Although the possibility cannot be entirely
excluded, it is unlikely that the planned project will result in any
cases of temporary or permanent hearing impairment, or any significant
non-auditory physical or physiological effects. Based on the available
data and studies described here, some behavioral disturbance is
expected. A more comprehensive review of these issues can be found in
the ``Programmatic Environmental Impact Statement/Overseas
Environmental Impact Statement for Marine Seismic Research funded by
the National Science Foundation or conducted by the U.S. Geological
Survey'' (NSF/USGS, 2011).
The notice of the proposed IHA (79 FR 464, January 3, 2014)
included a discussion of the effects of sounds from airguns,
icebreaking activities, core and dredge sampling, and other acoustic
devices and sources on mysticetes, odontocetes, and pinnipeds including
tolerance, masking, behavioral disturbance, hearing impairment, and
other non-auditory physical effects. The notice of the proposed IHA (79
FR 464, January 3, 2014) also included a discussion of the effects of
vessel movement and collisions as well as entanglement. NMFS refers
readers to NSF and ASC's application and IEE/EA for additional
information on the behavioral reactions (or lack thereof) by all types
of marine mammals to seismic vessels.
Anticipated Effects on Marine Mammal Habitat, Fish, and Invertebrates
NMFS included a detailed discussion of the potential effects of
this action on marine mammal habitat, including physiological and
behavioral effects on marine fish, fisheries, and invertebrates in the
notice of the proposed IHA (79 FR 464, January 3, 2014). The seismic
survey will not result in any permanent impact on habitats used by the
marine mammals in the survey area, including the food sources they use
(i.e., fish and invertebrates), and there will be no physical damage to
any habitat. While NMFS anticipates that the specified activity may
result in marine mammals avoiding certain areas due to temporary
ensonification, this impact to habitat is temporary and
inconsequential, which was considered in further detail in the notice
of the proposed IHA (79 FR 464, January 3, 2014), as behavioral
modification. The main impact associated with the activity will be
temporarily elevated noise levels and the associated direct effects on
marine mammals.
Mitigation
In order to issue an Incidental Take Authorization (ITA) under
section 101(a)(5)(D) of the MMPA, NMFS must set forth the permissible
methods of taking pursuant to such activity, and other means of
effecting the least practicable adverse impact on such species or stock
and its habitat, paying particular attention to rookeries, mating
grounds, and areas of similar significance, and the availability of
such species or stock for taking for certain subsistence uses.
NSF and ASC reviewed the following source documents and have
incorporated a suite of appropriate mitigation measures into their
project description.
(1) Protocols used during previous NSF and USGS-funded seismic
research cruises as approved by NMFS and detailed in the recently
completed NSF/USGS PEIS (2011);
(2) Previous IHA applications and IHAs approved and authorized by
NMFS; and
(3) Recommended best practices in Richardson et al. (1995), Pierson
et al. (1998), and Weir and Dolman, (2007).
To reduce the potential for disturbance from acoustic stimuli
associated with the activities, NSF, ASC and/or its designees are
required to implement the following mitigation measures for marine
mammals:
(1) Exclusion zones around the sound source;
(2) Speed and course alterations;
(3) Shut-down procedures; and
(4) Ramp-up procedures.
Exclusion Zones--During pre-planning of the cruise, the smallest
airgun array was identified that could be used and still meet the
geophysical scientific objectives. NSF and ASC use radii to designate
exclusion and buffer zones and to estimate take for marine mammals.
Table 4 (see below) shows the distances at which one would expect to
receive three sound levels (160, 180, and 190 dB) from the two GI
airgun array. The 180 and 190 dB level shut-down criteria are
applicable to cetaceans and pinnipeds, respectively, as specified by
NMFS (2000). NSF and ASC used these levels to establish the exclusion
and buffer zones.
Received sound levels have been modeled by L-DEO for a number of
airgun configurations, including two 45 in\3\ Nucleus G airguns, in
relation to distance and direction from the airguns (see Figure 2 of
the IHA application). In addition, propagation measurements of pulses
from two GI airguns have been reported for shallow water (approximately
30 m [98.4 ft] depth in the GOM (Tolstoy et al., 2004). However,
measurements were not made for the two GI airguns in deep water. The
model does not allow for bottom interactions, and is most directly
applicable to deep water. Based on the modeling, estimates of the
maximum distances from the GI airguns where sound levels are predicted
to be 190, 180, and 160 dB re 1 [micro]Pa (rms) in intermediate and
deep water were determined (see Table 4 below).
Empirical data concerning the 190, 180, and 160 dB (rms) distances
were acquired for various airgun arrays based on measurements during
the acoustic verification studies conducted by L-DEO in the northern
GOM in 2003 (Tolstoy et al., 2004) and 2007 to 2008 (Tolstoy et al.,
2009). Results of the 36 airgun array are not relevant for the two GI
airguns to be used in the planned survey. The empirical data for the 6,
10, 12, and 20 airgun arrays indicate that, for deep water, the L-DEO
model tends to overestimate the received sound levels at a given
distance (Tolstoy et al., 2004). Measurements were not made for the two
GI airgun array in deep water; however, NSF and ASC propose to use the
exclusion zone radii predicted by L-DEO's model for the planned GI
airgun operations in intermediate and deep water, although they are
likely conservative given the empirical results for the other arrays.
Based on the modeling data, the outputs from the pair of 45 in\3\
or 105 in\3\ GI airguns planned to be used during the seismic survey
are considered a low-energy acoustic source in the NSF/USGS PEIS (2011)
for marine seismic research. A low-energy seismic source was defined in
the NSF/USGS PEIS as an acoustic source whose received level at 100 m
is less than 180 dB. The NSF/USGS PEIS also established for these low-
energy sources, a standard exclusion zone of 100 m for all low-energy
sources in water depths greater
[[Page 14230]]
than 100 m. This standard 100 m exclusion zone will be used during the
planned low-energy seismic survey. The 180 and 190 dB (rms) radii are
shut-down criteria applicable to cetaceans and pinnipeds, respectively,
as specified by NMFS (2000); these levels were used to establish
exclusion zones. Therefore, the assumed 180 and 190 dB radii are 100 m
for intermediate and deep water, respectively. If the PSO detects a
marine mammal(s) within or about to enter the appropriate exclusion
zone, the airguns will be shut-down immediately.
Table 4 summarizes the predicted distances at which sound levels
(160, 180, and 190 dB [rms]) are expected to be received from the two
airgun array (45 in\3\ or 105 in\3\) operating in intermediate (100 to
1,000 m) and deep water (greater than 1,000 m) depths. Table 4.
Predicted and modeled (two 45 in\3\ and two 105 in\3\ GI airgun array)
distances to which sound levels >=190, 180 and 160 dB re: 1 [mu]Pa
(rms) could be received in intermediate and deep water during the
planned low-energy seismic survey in the Dumont d'Urville Sea of the
Southern Ocean, January to March 2014. No airgun operations will occur
in shallow (<100 m) water depths.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Predicted RMS radii distances (m) for 2 GI airgun array
Source and total volume Tow depth (m) Water depth (m) --------------------------------------------------------------------------------
160 dB 180 dB 190 dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
Two 45 in\3\ GI Airguns (90 3 Intermediate (100 to 600 (1,968.5 ft)............... 100 (328 ft).................. 100
in\3\). 1,000).
Two 45 in\3\ GI Airguns (90 3 Deep (>1,000)....... 400 (1,312.3 ft)............... 100........................... 100
in\3\).
Two 105 in\3\ GI Airguns (210 3 Intermediate (100 to 1,005 (3,297.2 ft)............. 100........................... 100
in\3\). 1,000).
Two 105 in\3\ GI Airguns (210 3 Deep (>1,000)....... 670 (2,198.2 ft)............... 100........................... 100
in\3\).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Speed and Course Alterations--If a marine mammal is detected
outside the exclusion zone and, based on its position and direction of
travel (relative motion), is likely to enter the exclusion zone,
changes of the vessel's speed and/or direct course will be considered
if this does not compromise operational safety or damage the deployed
equipment. This will be done if operationally practicable while
minimizing the effect on the planned science objectives. For marine
seismic surveys towing large streamer arrays, however, course
alterations are not typically implemented due to the vessel's limited
maneuverability. After any such speed and/or course alteration is
begun, the marine mammal activities and movements relative to the
seismic vessel will be closely monitored to ensure that the marine
mammal does not approach within the exclusion zone. If the marine
mammal appears likely to enter the exclusion zone, further mitigation
actions will be taken, including further speed and/or course
alterations, and/or shut-down of the airgun(s). Typically, during
seismic operations, the source vessel is unable to change speed or
course, and one or more alternative mitigation measures will need to be
implemented.
Shut-Down Procedures--NSF and ASC will shut-down the operating
airgun(s) if a marine mammal is detected outside the exclusion zone for
the airgun(s), and if the vessel's speed and/or course cannot be
changed to avoid having the animal enter the exclusion zone, the
seismic source will be shut-down before the animal is within the
exclusion zone. Likewise, if a marine mammal is already within the
exclusion zone when first detected, the seismic source will be shut-
down immediately.
Following a shut-down, NSF and ASC will not resume airgun activity
until the marine mammal has cleared the exclusion zone. NSF and ASC
will consider the animal to have cleared the exclusion zone if:
A PSO has visually observed the animal leave the exclusion
zone, or
A PSO has not sighted the animal within the exclusion zone
for 15 minutes for species with shorter dive durations (i.e., small
odontocetes and pinnipeds), or 30 minutes for species with longer dive
durations (i.e., mysticetes and large odontocetes, including sperm,
killer, and beaked whales).
Although power-down procedures are often standard operating
practice for seismic surveys, they are not going to be used during this
planned seismic survey because powering-down from two airguns to one
airgun will make only a small difference in the exclusion zone(s)--but
probably not enough to allow continued one-airgun operations if a
marine mammal came within the exclusion zone for two airguns.
Ramp-Up Procedures--Ramp-up of an airgun array provides a gradual
increase in sound levels and involves a step-wise increase in the
number and total volume of airguns firing until the full volume of the
airgun array is achieved. The purpose of a ramp-up is to ``warn''
marine mammals in the vicinity of the airguns and to provide the time
for them to leave the area avoiding any potential injury or impairment
of their hearing abilities. NSF and ASC will follow a ramp-up procedure
when the airgun array begins operating after a specified period without
airgun operations or when a shut-down shut down has exceeded that
period. NSF and ASC plans that, for the present cruise, this period
will be approximately 15 minutes. SIO, L-DEO, and USGS have used
similar periods (approximately 15 minutes) during previous low-energy
seismic surveys.
Ramp-up will begin with a single GI airgun (45 or 105 in\3\). The
second GI airgun (45 or 105 in\3\) will be added after 5 minutes.
During ramp-up, the PSOs will monitor the exclusion zone, and if marine
mammals are sighted, a shut-down will be implemented as though both GI
airguns were operational.
If the complete exclusion zone has not been visible for at least 30
minutes prior to the start of operations in either daylight or
nighttime, NSF and ASC will not commence the ramp-up. Given these
provisions, it is likely that the airgun array will not be ramped-up
from a complete shut-down at night or in thick fog, because the outer
part of the exclusion zone for that array will not be visible during
those conditions. If one airgun has operated, ramp-up to full power
will be permissible at night or in poor visibility, on the assumption
that marine mammals will be alerted to the approaching seismic vessel
by the sounds from the single airgun and could move away if they
choose. A ramp-up from a shut-down may occur at night, but only where
the exclusion zone is small enough to be visible. NSF and ASC will not
initiate a ramp-up of the airguns if a marine mammal is sighted within
or near the applicable exclusion
[[Page 14231]]
zones during the day or close to the vessel at night.
NMFS has carefully evaluated the applicant's mitigation measures
and has 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. NMFS's evaluation of potential measures included consideration
of the following factors in relation to one another:
(1) The manner in which, and the degree to which, the successful
implementation of the measure is expected to minimize adverse impacts
to marine mammals;
(2) The proven or likely efficacy of the specific measure to
minimize adverse impacts as planned; and
(3) The practicability of the measure for applicant implementation.
Based on NMFS's evaluation of the applicant's measures, as well as
other measures considered by NMFS or recommended by the public, NMFS
has determined that the mitigation measures provide the means of
effecting the least practicable impacts on marine mammal species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.
Monitoring and Reporting
In order to issue an ITA for an activity, section 101(a)(5)(D) of
the MMPA states that NMFS must set forth ``requirements pertaining to
the monitoring and reporting of such taking.'' The MMPA implementing
regulations at 50 CFR 216.104(a)(13) indicate that requests for IHAs
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 action area.
Monitoring
NSF and ASC will conduct marine mammal monitoring during the
project, in order to implement the mitigation measures that require
real-time monitoring, and to satisfy the monitoring requirements of the
IHA. NSF and ASC's ``Monitoring Plan'' is described below this section.
The monitoring work described here has been planned as a self-contained
project independent of any other related monitoring projects that may
be occurring simultaneously in the same regions. NSF and ASC will
discuss coordination of their monitoring program with any related work
that might be done by other groups insofar as this is practical and
desirable.
Vessel-Based Visual Monitoring
NSF and ASC's PSOs will be based aboard the seismic source vessel
and will watch for marine mammals near the vessel during icebreaking
activities, daytime airgun operations (austral summer) and during any
ramp-ups of the airguns at night. Generally, nighttime operations of
the airguns are not anticipated. PSOs will also watch for marine
mammals near the seismic vessel for at least 30 minutes prior to the
start of airgun operations and after an extended shut-down (i.e.,
greater than approximately 15 minutes for this low-energy seismic
survey). When feasible, PSOs will conduct observations during daytime
periods when the seismic system is not operating (such as during
transits) for comparison of sighting rates and behavior with and
without airgun operations and between acquisition periods. Based on PSO
observations, the airguns will be shut-down when marine mammals are
observed within or about to enter a designated exclusion zone. The
exclusion zone is a region in which a possibility exists of adverse
effects on animal hearing or other physical effects.
During seismic operations in the Dumont d'Urville Sea of the
Southern Ocean, at least two PSOs will be based aboard the Palmer. At
least one PSO will stand watch at all times while the Palmer is
operating airguns during the low-energy seismic survey; this procedure
will also be followed when the vessel is conducting icebreaking during
transit. NSF and ASC will appoint the PSOs with NMFS's concurrence. The
lead PSO will be experienced with marine mammal species in the Southern
Ocean, the second PSO will receive additional specialized training from
the PSO to ensure that they can identify marine mammal species commonly
found in the Southern Ocean. Observations will take place during
ongoing daytime operations and nighttime ramp-ups of the airguns.
During the majority of seismic operations, at least one PSO will be on
duty from observation platforms (i.e., the best available vantage point
on the source vessel) to monitor marine mammals near the seismic
vessel. PSO(s) will be on duty in shifts no longer than 4 hours in
duration. Other crew will also be instructed to assist in detecting
marine mammals and implementing mitigation requirements (if practical).
Before the start of the low-energy seismic survey, the crew will be
given additional instruction on how to do so. (Note: Because of the
high latitude locations of the study areas, twilight/darkness
conditions are expected to be limited to between 3 and 6 hours per day
during the planned action.)
The Palmer is a suitable platform for marine mammal observations
and will serve as the platform from which PSOs will watch for marine
mammals before and during seismic operations. Two locations are likely
as observation stations onboard the Palmer. Observing stations are
located on the bridge level, with the PSO eye level at approximately
16.5 m (54.1 ft) above the waterline and the PSO will have a good view
around the entire vessel. In addition, there is an aloft observation
tower for the PSO approximately 24.4 m (80.1 ft) above the waterline
that is protected from the weather, and affords PSOs an even greater
view. Standard equipment for PSOs will be reticle binoculars. Night-
vision equipment will not be available or required due to the constant
daylight conditions during the Antarctic summer. The PSOs will be in
communication with ship's officers on the bridge and scientists in the
vessel's operations laboratory, so they can advise promptly of the need
for avoidance maneuvers or seismic source shut-down. Observing stations
will be at the bridge level and the aloft observation tower. The
approximate view around the vessel from the bridge is 270[deg] and
360[deg] from the aloft observation tower. During daytime, the PSO(s)
will scan the area around the vessel systematically with reticle
binoculars (e.g., 7 x 50 Fujinon FMTRC-SX) and the naked eye. These
binoculars will have a built-in daylight compass. Estimating distances
is done primarily with the reticles in the binoculars. The PSO(s) will
be in direct (radio) wireless communication with ship's officers on the
bridge and scientists in the vessel's operations laboratory during
seismic operations, so they can advise the vessel operator, science
support personnel, and the science party promptly of the need for
avoidance maneuvers or a shut-down of the seismic source. PSOs will
monitor for the presence pinnipeds and cetaceans during icebreaking
activities, and will be limited to those marine mammal species in
proximity to the ice margin habitat. Observations within the buffer
zone will also include pinnipeds that may be present on the surface of
the sea ice (i.e., hauled-out) and that could potentially dive into the
water as the vessel approaches, indicating disturbance from noise
generated by icebreaking activities.
When marine mammals are detected within or about to enter the
designated exclusion zone, the airguns will
[[Page 14232]]
immediately be shut-down if necessary. The PSO(s) will continue to
maintain watch to determine when the animal(s) are outside the
exclusion zone by visual confirmation. Airgun operations will not
resume until the animal is confirmed to have left the exclusion zone,
or if not observed after 15 minutes for species with shorter dive
durations (small odontocetes and pinnipeds) or 30 minutes for species
with longer dive durations (mysticetes and large odontocetes, including
sperm, killer, and beaked whales).
PSO Data and Documentation
PSOs will record data to estimate the numbers of marine mammals
exposed to various received sound levels and to document apparent
disturbance reactions or lack thereof. Data will be used to estimate
numbers of animals potentially ``taken'' by harassment (as defined in
the MMPA). They will also provide information needed to order a shut-
down of the airguns when a marine mammal is within or near the
exclusion zone. Observations will also be made during icebreaking
activities as well as daytime periods when the Palmer is underway
without seismic operations (i.e., transits, to, from, and through the
study area) to collect baseline biological data.
When a sighting is made, the following information about the
sighting will be recorded:
1. Species, group size, age/size/sex categories (if determinable),
behavior when first sighted and after initial sighting, heading (if
consistent), bearing and distance from seismic vessel, sighting cue,
apparent reaction to the seismic source or vessel (e.g., none,
avoidance, approach, paralleling, etc.), and behavioral pace.
2. Time, location, heading, speed, activity of the vessel, sea
state, wind force, visibility, and sun glare.
The data listed under (2) will also be recorded at the start and
end of each observation watch, and during a watch whenever there is a
change in one or more of the variables.
All observations, as well as information regarding ramp-ups or
shut-downs will be recorded in a standardized format. Data will be
entered into an electronic database. The data accuracy will be verified
by computerized data validity checks as the data are entered and by
subsequent manual checking of the database by the PSOs at sea. These
procedures will allow initial summaries of data to be prepared during
and shortly after the field program, and will facilitate transfer of
the data to statistical, graphical, and other programs for further
processing and archiving.
Results from the vessel-based observations will provide the
following information:
1. The basis for real-time mitigation (airgun shut-down).
2. Information needed to estimate the number of marine mammals
potentially taken by harassment, which must be reported to NMFS.
3. Data on the occurrence, distribution, and activities of marine
mammals in the area where the seismic study is conducted.
4. Information to compare the distance and distribution of marine
mammals relative to the source vessel at times with and without seismic
activity.
5. Data on the behavior and movement patterns of marine mammals
seen at times with and without seismic activity.
NSF and ASC will submit a comprehensive report to NMFS within 90
days after the end of the cruise. The report will describe the
operations that were conducted and sightings of marine mammals near the
operations. The report submitted to NMFS will provide full
documentation of methods, results, and interpretation pertaining to all
monitoring. The 90-day report will summarize the dates and locations of
seismic operations and all marine mammal sightings (i.e., dates, times,
locations, activities, and associated seismic survey activities). The
report will include:
Summaries of monitoring effort--total hours, total
distances, and distribution of marine mammals through the study period
accounting for Beaufort sea state and other factors affecting
visibility and detectability of marine mammals;
Analyses of the effects of various factors influencing
detectability of marine mammals including Beaufort sea state, number of
PSOs, and fog/glare;
Species composition, occurrence, and distribution of
marine mammals sightings including date, water depth, numbers, age/
size/gender, and group sizes; and analyses of the effects of seismic
operations;
Sighting rates of marine mammals during periods with and
without airgun activities (and other variables that could affect
detectability);
Initial sighting distances versus airgun activity state;
Closest point of approach versus airgun activity state;
Observed behaviors and types of movements versus airgun
activity state;
Numbers of sightings/individuals seen versus airgun
activity state; and
Distribution around the source vessel versus airgun
activity state.
The report will also include estimates of the number and nature of
exposures that could result in ``takes'' of marine mammals by
harassment or in other ways. After the report is considered final, it
will be publicly available on the NMFS Web site at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#iha.
In the unanticipated event that the specified activity clearly
causes the take of a marine mammal in a manner prohibited by this IHA,
such as an injury (Level A harassment), serious injury or mortality
(e.g., ship-strike, gear interaction, and/or entanglement), NSF and ASC
will immediately cease the specified activities and 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
[email protected] and [email protected]. 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 shall not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS will work with NSF and ASC
to determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. NSF and ASC may not resume
their activities until notified by NMFS via letter or email, or
telephone.
In the event that NSF and ASC 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),
NSF and ASC will 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 [email protected] and
[email protected]. The report
[[Page 14233]]
must include the same information identified in the paragraph above.
Activities may continue while NMFS reviews the circumstances of the
incident. NMFS will work with NSF and ASC to determine whether
modifications in the activities are appropriate.
In the event that NSF and ASC 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 or advanced
decomposition, or scavenger damage), NSF and ASC will 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
[email protected] and [email protected], within 24 hours
of discovery. NSF and ASC will provide photographs or video footage (if
available) or other documentation of the stranded animal sighting to
NMFS. Activities may continue while NMFS reviews the circumstances of
the incident.
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].
Level B harassment of marine mammals is anticipated to result from
the low-energy marine seismic survey in the Dumont d'Urville Sea off
the coast of East Antarctica. Acoustic stimuli (i.e., increased
underwater sound) generated during the operation of the seismic airgun
array and icebreaking activities are expected to result in the
behavioral disturbance of some marine mammals. There is no evidence
that the planned activities could result in injury, serious injury, or
mortality for which NSF and ASC seeks the IHA. The required mitigation
and monitoring measures are expected to minimize any potential risk for
injury, serious injury, or mortality.
The following sections describe NSF and ASC's methods to estimate
take by incidental harassment and present the applicant's estimates of
the numbers of marine mammals that could be affected during the low-
energy seismic survey in the Dumont d'Urville Sea off the coast of East
Antarctica. The estimates are based on a consideration of the number of
marine mammals that could be harassed during the approximately 2,800 km
(1,511.9 nmi) of seismic airgun operations with the two GI airgun array
to be used and 1,000 km of icebreaking activities.
During simultaneous operations of the airgun array and the other
sound sources, any marine mammals close enough to be affected by the
single and multi-beam echosounders, pingers, ADCP, sub-bottom profiler,
etc. would already be affected by the airguns. During times when the
airguns are not operating, it is unlikely that marine mammals will
exhibit more than minor, short-term responses to the echosounders,
ADCPs, and sub-bottom profiler given their characteristics (e.g.,
narrow, downward-directed beam) and other considerations described
previously. Therefore, for this activity, take was not authorized
specifically for these sound sources beyond that which is already
authorized for airguns and icebreaking activities.
There are no stock assessments and very limited population
information available for marine mammals in the Dumont d'Urville Sea.
Published estimates of marine mammal densities are not available for
the Dumont d'Urville Sea. Sighting data from the Australian Antarctic
Division's (AAD) BROKE-West surveys (1999) were used to determine and
estimate marine mammals densities for mysticetes and odontocetes and
AAD data components for pinnipeds (Southwell et al., 2008; 2012), which
were not available for the seismic survey's action area in the Dumont
d'Urville Sea. The specific densities used for crabeater seals are
based on data from Southwell et al. (2008) and for Weddell seals is
based on NMFS Southwest Fisheries Science Center (2013) and IUCN data.
While population density data for cetaceans in the Southern Ocean are
sparse to nonexistent, reported sightings data from previous research
cruises suggest cetaceans such as those identified in Table 12 of the
IHA application span a range greater than 4,000 km (2,159.8 nmi) off
the coast of East Antarctica. The AAD BROKE-West survey was not
specifically designed to quantify marine mammals. Observations from
this survey represent sightings from a discrete time period. The data
were in terms of animals sighted per time unit, and the sighting data
were then converted to an areal density (number of animals per square
km) by multiplying the number of animals observed by the estimated area
observed during the survey. As such, some marine mammals that were
present in the area may not have been observed.
The estimated number of cetaceans and pinnipeds that may be
potentially exposed to the seismic airgun operations and icebreaking
activities were based on sighting data from previous research cruises
over a 52-day period and 13-day period. Some of the AAD sighting data
were used as the basis for estimating take included ``unidentified
whale'' species, this category was retained and pro-rated to the other
species because environmental conditions may be present during the
planned action to limit identification of observed cetaceans. The
estimated frequency of sightings data for cetaceans incorporates a
correction factor of 5 that assumes only 20% of the animals present
were reported due to sea ice and other conditions that may have
hindered observation. The 20% factor was intended to conservatively
account for this. A 40% correction factor to account for seals that may
be in the water versus those hauled-out on ice surface was used for
pinnipeds in the proposed IHA, but has since been removed. The 40%
correction factor was removed as pinnipeds hauled-out on ice often
flush into the water and may be exposed to sounds from the airgun
operations or icebreaking activities from the Palmer. The correction
factor for pinnipeds was conservatively based on Southwell et al.
(2012), which estimated 20 to 40% of crabeater seals may be in the
water in a particular area while the rest are hauled-out. The
correction factor took into consideration some pinnipeds may not be
observed due to poor visibility conditions.
Sightings data were collected by the AAD; however, the AAD
methodology was not described. Density is generally reported in the
number of animals per km or square km. Estimated area observed by
observers was calculated by using the average vessel speed (5.6 km/hr)
times the estimated hours of the survey to estimate the total distance
covered for each of the surveys. This was then converted from the
linear distance into an area by assuming a width of 5 km that could be
reliably visually surveyed. Therefore, the estimated area was 5,753
km\2\ (1,677.3 nmi\2\) to obtain mysticete and odontocete densities and
the estimated area was 1,419 km\2\ (413.7 nmi\2\) to obtain pinniped
densities.
Of the six species of pinnipeds that may be present in the study
area during the planned action, only four species are expected to be
observed and occur mostly near pack ice or coastal areas
[[Page 14234]]
and are not prevalent in open sea areas where the low-energy seismic
survey will be conducted. Because density estimates for pinnipeds in
that Antarctic region typically represent individuals that have hauled-
out of the water, those estimates are not representative of individuals
that are in the water and could be potentially exposed to underwater
sounds during the seismic airgun operations and icebreaking activities;
therefore, the pinniped densities have been adjusted to account for
this concern. Take was not requested for southern elephant seals and
Antarctic fur seals because preferred habitat for these species is not
within the planned action area. Although no sightings of Weddell seals
and spectacled porpoises were reported in the BROKE-West sighting data,
take was requested for these species based on NMFS recommendation and
IWC SOWER data. Although there is some uncertainty about the
representativeness of the data and the assumptions used in the
calculations below, the approach used here is believed to be the best
available approach.
Table 5. Estimated densities and possible number of marine mammal
species that might be exposed to greater than or equal to 120 dB
(icebreaking) and 160 dB (airgun operations) during NSF and ASC's
planned low-energy seismic survey (approximately 1,000 km of
tracklines/approximately 21,540 km\2\ ensonified area for icebreaking
activities and approximately 2,800 km of tracklines/approximately 5,628
km\2\ ensonified area for airgun operations) in the Dumont d'Urville
Sea of the Southern Ocean, January to March 2014.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Calculated Calculated
take from take from
Reported seismic airgun icebreaking
sightings \1\ operations activities Approximate
\2\ *sightings Corrected (i.e., (i.e., percentage of
have been pro- sightings Density estimated estimated population Total take
Species rated to (assume 20% (/ number of number of estimate authorized \6\
include for cetaceans) km\2\) individuals individuals (calculated
unidentified exposed to exposed to total take)
animals* sound levels sound levels \5\
>= 160 dB re 1 >= 120 dB re 1
[mu]Pa) \3\ [mu]Pa) \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes:
Southern right whale.......... 0 0 0 0 0 0 0
Humpback whale................ 238 1,190 0.1029768 580 2,218 8.0 580 + 2,218 = 2,798
Antarctic minke whale......... 136 680 0.0588439 331 1,267 0.53 331 + 1,267 = 1,598
Sei whale..................... 4 20 0.0017307 10 37 0.06 10 + 37 = 47
Fin whale..................... 232 1,160 0.1003808 565 2,162 1.9 565 + 2,162 = 2,727
Blue whale.................... 2 10 0.0008654 5 19 1.4 5 + 19 = 24
Odontocetes:
Sperm whale................... 32 160 0.0138456 78 298 3.9 78 + 298 = 376
Arnoux's beaked whale......... 0 0 0 0 0 NA 0
Cuvier's beaked whale......... 0 0 0 0 0 NA 0
Southern bottlenose whale..... 0 0 0 0 0 NA 0
Killer whale.................. 62 310 0.0268259 151 578 2.9 151 + 578 = 729
Long-finned pilot whale....... 24 120 0.0103842 58 224 0.1 58 + 224 = 282
Hourglass dolphin............. 26 130 0.0112496 63 242 0.2 63 + 242 = 305
Spectacled porpoise........... 33 165 0.0142783 80 308 NA 80 + 308 = 388
Pinnipeds:
Crabeater seal................ NA NA 0.868000 4,885 18,697 0.5 4,885 + 18,697 =
23,582
Leopard seal.................. 17 24 0.051486 290 1,109 0.6 290 + 1,109 = 1,399
Ross seal..................... 42 59 0.127201 716 2,740 2.7 716 + 2,740 = 3,456
Weddell seal.................. NA NA 0.0756 425 1,628 0.4 425 + 1,628 = 2,053
Southern elephant seal........ 0 0 0 0 0 NA 0
Antarctic fur seal............ 0 0 0 0 0 NA 0
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA = Not available or not assessed.
\1\ Sightings from a 52 day (5,753 km\2\) period on the AAD BROKE-West survey during January to March 2006.
\2\ Sightings December 3 to 16, 1999 (1,420 km\2\ and 75,564 km\2\) below 60[deg] South latitude between 110 to 165[deg] East longitude. All sightings
were animals hauled-out of the water and on the sea ice.
\3\ Calculated take is estimated density (reported density times correction factor) multiplied by the area ensonified to 160 dB (rms) around the planned
seismic lines, increased by 25% for contingency.
\4\ Calculated take is estimated density (reported density) multiplied by the area ensonified to 120 dB (rms) around the planned transit lines where
icebreaking activities may occur.
\5\ Total requested (and calculated) takes expressed as percentages of the species or regional populations.
\6\ Requested Take Authorization includes unidentified animals that were added to the observed and identified species on a pro-rated basis.
Note: Take was not requested for southern elephant seals and Antarctic fur seals because preferred habitat for these species is not within the action
area.
Icebreaking in Antarctic waters will occur, as necessary, between
the latitudes of approximately 66 to 70[deg] South and between 140 and
165[deg] East, and between approximately 65 to 66[deg] South and
between 95 to 135[deg] East. Based on a maximum sea ice extent of 250
km and estimating that the Palmer will transit to the innermost shelf
and back into open water twice--a round trip transit in each of the
potential work regions, it is estimated that the Palmer will actively
break ice up to a distance of 1,000 km. Based on the ship's speed of 5
kts under moderate ice conditions, this distance represents
approximately 108 hrs of icebreaking operations. This calculation is
likely an overestimation because icebreakers often follow leads when
they are available and thus do not break ice at all times.
Numbers of marine mammals that might be present and potentially
disturbed are estimated based on the available data about marine mammal
distribution and densities in the Southern Ocean study are during the
austral summer. NSF and ASC estimated the number of different
individuals that may be exposed to airgun sounds with received levels
greater than or equal to 160 dB re 1 [mu]Pa (rms) for seismic airgun
operations and greater than or equal to 120 dB re 1 [mu]Pa (rms) for
icebreaking activities on one or more occasions by considering the
total marine area that will be within the 160 dB radius around the
operating airgun array and 120 dB radius for the icebreaking activities
on at least one occasion and the expected density of marine mammals in
the area (in the
[[Page 14235]]
absence of the a seismic survey and icebreaking activities). The number
of possible exposures can be estimated by considering the total marine
area that will be within the 160 dB radius (i.e., diameter is 1,005 m
times 2) around the operating airguns. The ensonified area for
icebreaking was estimated by multiplying the distance of the
icebreaking activities (1,000 km) by the estimated diameter of the area
within the 120 dB radius (i.e., diameter is 21,544 m). The 160 dB radii
are based on acoustic modeling data for the airguns that may be used
during the action (see Attachment B of the IHA application). As
summarized in Table 2 (see Table 11 of the IHA application), the
modeling results for the planned low-energy seismic airgun array
indicate the received levels are dependent on water depth. Since the
majority of the planned airgun operations will be conducted in waters
100 to 1,000 m deep, the buffer zone of 1,005 m used for the two 105
in\3\ GI airguns was used to be more conservative. The expected
sighting data for pinnipeds accounts for both pinnipeds that may be in
the water and those hauled-out on ice surfaces. While the number of
cetaceans that may be encountered within the ice margin habitat will be
expected to be less than open water, the estimates utilized expected
sightings for the open water and represent conservative estimates. It
is unlikely that a particular animal will stay in the area during the
entire survey.
The number of different individuals potentially exposed to received
levels greater than or equal to 160 dB re 1 [mu]Pa (rms) from seismic
airgun operations and 120 dB re 1 [mu]Pa (rms) for icebreaking
activities was calculated by multiplying:
(1) The expected species density (in number/km\2\), and
(2) The anticipated area to be ensonified to that level during
airgun operations.
Applying the approach described above, approximately 5,628 km\2\
(including the 25% contingency) will be ensonified within the 160 dB
isopleth for seismic airgun operations and approximately 21,540 km\2\
will be ensonified within the 120 dB isopleth for icebreaking
activities on one or more occasions during the survey. The take
calculations within the study sites do not explicitly add animals to
account for the fact that new animals (i.e., turnover) are not
accounted for in the initial density snapshot and animals could also
approach and enter the area ensonified above 160 dB for seismic airgun
operations and 120 dB for icebreaking activities; however, studies
suggest that many marine mammals will avoid exposing themselves to
sounds at this level, which suggests that there will not necessarily be
a large number of new animals entering the area once the seismic survey
and icebreaking activities started. Because this approach for
calculating take estimates does not allow for turnover in the marine
mammal populations in the area during the course of the survey, the
actual number of individuals exposed may be underestimated, although
the conservative (i.e., probably overestimated) line-kilometer
distances used to calculate the area may offset this. Also, the
approach assumes that no cetaceans or pinnipeds will move away or
toward the tracklines as the Palmer approaches in response to
increasing sound levels before the levels reach 160 dB for seismic
airgun operations and 120 dB for icebreaking activities. Another way of
interpreting the estimates that follow is that they represent the
number of individuals that are expected (in absence of a seismic airgun
and icebreaking program) to occur in the waters that will be exposed to
greater than or equal to 160 dB (rms) for seismic airgun operations and
greater than or equal to 120 dB (rms) for icebreaking activities.
NSF and ASC's estimates of exposures to various sound levels assume
that the planned surveys will be carried out in full; however, the
ensonified areas calculated using the planned number of line-kilometers
has been increased by 25% to accommodate lines that may need to be
repeated, equipment testing, etc. As is typical during offshore ship
surveys, inclement weather and equipment malfunctions are likely to
cause delays and may limit the number of useful line-kilometers of
seismic operations that can be undertaken. The estimates of the numbers
of marine mammals potentially exposed to 120 dB (rms) and 160 dB (rms)
received levels are precautionary and probably overestimate the actual
numbers of marine mammals that could be involved. These estimates
assume that there will be no weather, equipment, or mitigation delays,
which is highly unlikely.
Table 5 shows the estimates of the number of different individual
marine mammals anticipated to be exposed to greater than or equal to
120 dB re 1 [mu]Pa (rms) for icebreaking activities and greater than or
equal to 160 dB re 1 [mu]Pa (rms) for seismic airgun operations during
the seismic survey if no animals moved away from the survey vessel. The
total take authorized is given in the far right column of Table 5.
Encouraging and Coordinating Research
NSF and ASC will coordinate the planned marine mammal monitoring
program associated with the low-energy seismic survey with other
parties that express interest in this activity and area. NSF and ASC
will coordinate with applicable U.S. agencies (e.g., NMFS), and will
comply with their requirements. NSF has already reached out to the
Australian Antarctic Division (AAD), who are the proponents of the
proposed marine protected area and regularly conduct research
expeditions in the marine environment off East Antarctica.
The planned action will complement fieldwork studying other
Antarctic ice shelves, oceanographic studies, and ongoing development
of ice sheet and other ocean models. It would facilitate learning at
sea and ashore by students, help to fill important spatial and temporal
gaps in a lightly sampled region of coastal Antarctica, provide
additional data on marine mammals present in the East Antarctic study
areas, and communicate its findings via reports, publications and
public outreach.
Impact on Availability of Affected Species or Stock for Taking for
Subsistence Uses
Section 101(a)(5)(D) of the MMPA also requires NMFS to determine
that the authorization will not have an unmitigable adverse effect on
the availability of marine mammal species or stocks for subsistence
use. There are no relevant subsistence uses of marine mammals in the
study area (in the Dumont d'Urville Sea off the coast of East
Antarctica) that implicate MMPA section 101(a)(5)(D).
Analysis and Determinations
Negligible Impact
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 evaluated
factors such as:
(1) The number of anticipated injuries, serious injuries, or
mortalities;
(2) The number, nature, and intensity, and duration of Level B
harassment (all relatively limited); and
(3) The context in which the takes occur (i.e., impacts to areas of
significance, impacts to local populations, and cumulative impacts
[[Page 14236]]
when taking into account successive/contemporaneous actions when added
to baseline data);
(4) The status of stock or species of marine mammals (i.e.,
depleted, not depleted, decreasing, increasing, stable, impact relative
to the size of the population);
(5) Impacts on habitat affecting rates of recruitment/survival; and
(6) The effectiveness of monitoring and mitigation measures.
For reasons stated previously in this document, in the notice of
the proposed IHA (79 FR 464, January 3, 2014) and based on the
following factors, the specified activities associated with the marine
seismic survey are not likely to cause PTS, or other non-auditory
injury, serious injury, or death. The factors include:
(1) The likelihood that, given sufficient notice through relatively
slow ship speed, marine mammals are expected to move away from a noise
source that is annoying prior to its becoming potentially injurious;
and
(2) The potential for temporary or permanent hearing impairment is
relatively low and will likely be avoided through the implementation of
the shut-down measures.
No injuries, serious injuries, or mortalities are anticipated to
occur as a result of the NSF and ASC's planned low-energy marine
seismic survey, and none are authorized by NMFS. Table 5 of this
document outlines the number of requested Level B harassment takes that
are anticipated as a result of these activities. Due to the nature,
degree, and context of Level B (behavioral) harassment anticipated and
described (see ``Potential Effects on Marine Mammals'' section above)
in this notice, the activity is not expected to impact rates of annual
recruitment or survival for any affected species or stock, particularly
given the requirement to implement mitigation, monitoring, and
reporting measures to minimize impacts to marine mammals. Additionally,
the seismic survey will not adversely impact marine mammal habitat.
For the marine mammal species that may occur within the action
area, there are no known designated or important feeding and/or
reproductive areas. Many animals perform vital functions, such as
feeding, resting, traveling, and socializing, on a diel cycle (i.e., 24
hr cycle). Behavioral reactions to noise exposure (such as disruption
of critical life functions, displacement, or avoidance of important
habitat) are more likely to be significant if they last more than one
diel cycle or recur on subsequent days (Southall et al., 2007).
Additionally, the seismic survey will be increasing sound levels in the
marine environment in a relatively small area surrounding the vessel
(compared to the range of the animals), which is constantly travelling
over distances, and some animals may only be exposed to and harassed by
sound for less than a day.
Of the 14 marine mammal species under NMFS jurisdiction that may or
are known to likely to occur in the study area, five are listed as
threatened or endangered under the ESA: Southern right, humpback, sei,
fin, blue, and sperm whales. These species are also considered depleted
under the MMPA. Of these ESA-listed species, incidental take has been
requested to be authorized for humpback, sei, fin, blue, and sperm
whales. There is generally insufficient data to determine population
trends for the other depleted species in the study area. To protect
these animals (and other marine mammals in the study area), NSF and ASC
must cease or reduce airgun operations if any marine mammal enters
designated zones. No injury, serious injury, or mortality is expected
to occur and due to the nature, degree, and context of the Level B
harassment anticipated, and the activity is not expected to impact
rates of recruitment or survival.
As mentioned previously, NMFS estimates that 14 species of marine
mammals under its jurisdiction could be potentially affected by Level B
harassment over the course of the IHA. The population estimates for the
marine mammal species that may be taken by Level B harassment were
provided in Table 4 of this document.
NMFS's practice has been to apply the 160 dB re 1 [mu]Pa (rms)
received level threshold for underwater impulse sound levels and the
120 dB re 1 [mu]Pa (rms) received level threshold for icebreaking
activities to determine whether take by Level B harassment occurs.
Southall et al. (2007) provide a severity scale for ranking observed
behavioral responses of both free-ranging marine mammals and laboratory
subjects to various types of anthropogenic sound (see Table 4 in
Southall et al. [2007]).
NMFS has determined, provided that the aforementioned mitigation
and monitoring measures are implemented, the impact of conducting a
low-energy marine seismic survey in the Dumont d'Urville Sea off the
coast of East Antarctica, January to March 2014, may result, at worst,
in a modification in behavior and/or low-level physiological effects
(Level B harassment) of certain species of marine mammals.
While behavioral modifications, including temporarily vacating the
area during the operation of the airgun(s), may be made by these
species to avoid the resultant acoustic disturbance, the availability
of alternate areas within these areas for species and the short and
sporadic duration of the research activities, have led NMFS to
determine that the taking by Level B harassment from the specified
activity will have a negligible impact on the affected species in the
specified geographic region. NMFS believes that the length of the
seismic survey, the requirement to implement mitigation measures (e.g.,
shut-down of seismic operations), and the inclusion of the monitoring
and reporting measures, will reduce the amount and severity of the
potential impacts from the activity to the degree that it will have a
negligible impact on the species or stocks in the action area.
Small Numbers
The estimate of the number of individual cetaceans and pinnipeds
that could be exposed to seismic sounds with received levels greater
than or equal to 160 dB re 1 [mu]Pa (rms) and sounds from icebreaking
activities with received levels greater than or equal to 120 dB re 1
[mu]Pa (rms) during the survey is (with 25% contingency) in Table 5 of
this document. That total (with 25% contingency) includes 2,798
humpback, 1,598 Antarctic minke, 47 sei, 2,727 fin, 24 blue, and 376
sperm whales could be taken by Level B harassment during the seismic
survey, which will represent 8, 0.53, 0.06, 1.9, 1.4, and 3.9% of the
worldwide or regional populations, respectively. Some of the cetaceans
potentially taken by Level B harassment are delphinids and porpoises:
Killer whales, long-finned pilot whales, hourglass dolphins, and
spectacled porpoises are estimated to be the most common delphinid and
porpoise species in the area, with estimates of 729, 282, 305, and 308,
which will represent 2.9, 0.1, and 0.2% (spectacled porpoise population
is not available) of the affected worldwide or regional populations,
respectively. Most of the pinnipeds potentially taken by Level B
harassment are: Crabeater, leopard, Ross, and Weddell seals with
estimates of 23,582, 1,399, 3,456, and 2,053, which will represent 0.5,
0.6, 2.7, and 0.4% of the affected worldwide or regional populations,
respectively.
NMFS has determined, provided that the aforementioned mitigation
and monitoring measures are implemented, that the impact of conducting
a low-energy marine seismic survey in the Dumont d'Urville Sea off the
coast of East Antarctica, January to March 2014, may result, at worst,
in a temporary modification in behavior and/or low-level physiological
effects (Level B
[[Page 14237]]
harassment) of small numbers of certain species of marine mammals. The
requested take estimates represent small numbers relative to the
affected species or stock sizes (i.e., all are less than or equal to
8%). See Table 5 for the requested authorized take numbers of marine
mammals.
Endangered Species Act
Of the species of marine mammals that may occur in the survey area,
several are listed as endangered under the ESA, including the humpback,
sei, fin, blue, and sperm whales. NSF and ASC did not request take of
endangered Southern right whales due to the low likelihood of
encountering this species during the cruise. Under section 7 of the
ESA, NSF, on behalf of ASC and five other research institutions,
initiated formal consultation with the NMFS, Office of Protected
Resources, Endangered Species Act Interagency Cooperation Division, on
this low-energy seismic survey. NMFS's Office of Protected Resources,
Permits and Conservation Division, also initiated formal consultation
under section 7 of the ESA with the Endangered Species Act Interagency
Cooperation Division, to obtain a Biological Opinion evaluating the
effects of issuing the IHA under section 101(a)(5)(D) of the MMPA on
threatened and endangered marine mammals. These two consultations were
consolidated and addressed in a single Biological Opinion addressing
the effects of these actions. NMFS's Biological Opinion concluded that
the action and issuance of the IHA are not likely to jeopardize the
continued existence of listed species and included an Incidental Take
Statement incorporating the requirements of the IHA as Terms and
Conditions. The Biological Opinion also concluded that designated
critical habitat of these species does not occur in the action area.
National Environmental Policy Act
NSF and ASC provided NMFS a ``Initial Environmental Evaluation/
Environmental Assessment to Conduct Marine-Based Studies of the Totten
Glacier System and Marine Record of Cryosphere--Ocean Dynamics,'' (IEE/
EA) prepared by AECOM on behalf of NSF and ASC. The IEE/EA analyzes the
direct, indirect, and cumulative environmental impacts of the planned
specified activities on marine mammals including those listed as
threatened or endangered under the ESA. NMFS, after review and
evaluation of the NSF and ASC IEE/EA for consistency with the
regulations published by the Council of Environmental Quality (CEQ) and
NOAA Administrative Order 126-6, Environmental Review Procedures for
Implementing the National Environmental Policy Act, prepared an
independent Environmental Assessment (EA) titled ``Environmental
Assessment on the Issuance of an Incidental Harassment Authorization to
the National Science Foundation and Antarctic Support Contract to Take
Marine Mammals by Harassment Incidental to a Low-Energy Marine
Geophysical Survey in the Dumont d'Urville Sea off the Coast of East
Antarctica, January to March 2014.'' NMFS has determined that the
issuance of the IHA is not likely to result in significant impacts on
the human environment and issued a Finding of No Significant Impact
(FONSI).
Authorization
NMFS has issued an IHA to NSF and ASC for the take, by Level B
harassment, of small numbers of marine mammals incidental to conducting
a low-energy marine seismic survey in the Dumont d'Urville Sea off the
coast of East Antarctica, provided the previously mentioned mitigation,
monitoring, and reporting requirements are incorporated.
Dated: March 4, 2014.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2014-05396 Filed 3-12-14; 8:45 am]
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