[Federal Register Volume 77, Number 130 (Friday, July 6, 2012)]
[Notices]
[Pages 40007-40023]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-16584]
[[Page 40007]]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XY11
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to Marine Seismic Survey in the
Beaufort Sea, Alaska
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; issuance of an incidental take authorization.
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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 BP Exploration (Alaska),
Inc. (BP) to take, by harassment, small numbers of 10 species of marine
mammals incidental to ocean bottom cable (OBC) seismic surveys in the
Simpson Lagoon area of the Beaufort Sea, Alaska, during the 2012 Arctic
open-water season.
DATES: Effective July 1, 2011, through October 15, 2012.
ADDRESSES: Inquiry for information on the incidental take authorization
should be addressed to P. Michael Payne, Chief, Permits and
Conservation Division, Office of Protected Resources, National Marine
Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910. A
copy of the application containing a list of the references used in
this document, NMFS' Environmental Assessment (EA), Finding of No
Significant Impact (FONSI), and the IHA may be obtained by writing to
the address specified above, telephoning the contact listed below (see
FOR FURTHER INFORMATION CONTACT), or visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.
Documents cited in this notice may be viewed, by appointment,
during regular business hours, at the aforementioned address.
FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected
Resources, NMFS, (301) 427-8401 or Brad Smith, NMFS, Alaska Region,
(907) 271-3023.
SUPPLEMENTARY INFORMATION:
Background
Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
direct the Secretary of Commerce (Secretary) to allow, upon request,
the incidental, but not intentional taking of marine mammals by U.S.
citizens who engage in a specified activity (other than commercial
fishing) within a specified geographical region if certain findings are
made and regulations are issued or, if the taking is limited to
harassment, a notice of a proposed authorization is provided to the
public for review.
Authorization shall be granted if NMFS finds that the taking will
have a negligible impact on the species or stock(s), will not have an
unmitigable adverse impact on the availability of the species or
stock(s) for subsistence uses (where relevant), and if the permissible
methods of taking and requirements pertaining to the mitigation,
monitoring and reporting of such taking are set forth.
NMFS has defined ``negligible impact'' in 50 CFR 216.103 as:
an impact resulting from the specified activity that cannot be
reasonably expected to, and is not reasonably likely to, adversely
affect the species or stock through effects on annual rates of
recruitment or survival.
Section 101(a)(5)(D) of the MMPA established an expedited process
by which citizens of the U.S. can apply for an authorization to
incidentally take small numbers of marine mammals by 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].
Section 101(a)(5)(D) establishes a 45-day time limit for NMFS
review of an application followed by a 30-day public notice and comment
period on any proposed authorizations for the incidental harassment of
marine mammals. Within 45 days of the close of the comment period, NMFS
must either issue or deny issuance of the authorization.
Summary of Request
NMFS received an application on December 20, 2011, from BP for the
taking, by harassment, of marine mammals incidental to a 3D OBC seismic
survey in the Simpson Lagoon area of the Alaskan Beaufort Sea during
the open water season of 2012.
Description of the Specified Activity
The proposed seismic survey utilizes receivers (hydrophones and
geophones) connected to a cable that would be deployed from a vessel to
the seabed or would be inserted in the seabed in very shallow water
areas near the shoreline. The generation of 3D seismic images requires
the deployment of many parallel cables spaced close together over the
area of interest. Therefore, OBC seismic surveys require the use of
multiple vessels for cable deployment and recovery, data recording,
airgun operation, re-supply, and support. The proposed 3D OBC seismic
survey in Simpson Lagoon would be conducted by CGGVeritas.
Seismic Source Arrays
A total of three seismic source vessels (two main source vessels
and one mini source vessel) would be used during the proposed survey.
The sources would be arrays of sleeve airguns. Each main source vessel
would carry an array that consists of two sub-arrays. Each sub-array
contains eight 40 in\3\ airguns, totaling 16 guns per main source
vessel with a total discharge volume of 2 x 320 in\3\, or 640 in\3\.
This 640 in\3\ array has an estimated source level of ~223 dB re 1
[mu]Pa (rms). The mini source vessel would contain one array with eight
40 in\3\ airguns for a total discharge volume of 320 in\3\. The
estimated source level of this 320 in\3\ array is 212 dB re 1 [mu]Pa
(rms).
The arrays of the main source vessels would be towed at a distance
of ~30 feet (ft, or 10 m) from the stern at 6 ft (2 m) depth, which is
remotely adjustable if needed. The array of the mini source vessel
would be towed at a distance of ~20 ft (7 m) from the stern at 3 ft (1
m) depth, also remotely adjustable when needed. The source vessels will
travel along pre-determined lines with a speed varying from ~1 to 5
knots, mainly depending on the water depth. To limit the duration of
the total survey, the source vessels would be operating in a flip-flop
mode, with the operating source vessels alternating shots; this means
that one vessel discharges airguns when the other vessel is recharging.
Outside the barrier islands, the two main source vessels would be
operating with expected shot intervals of 8 to 10 seconds, resulting in
a shot every 4 to 5 seconds due to the flip-flop mode of operation.
Inside the barrier islands all three vessels (the two main source
vessels and the mini vessel) may be operating at the same time in this
manner. The exact shot intervals would depend on the compressor
capacity, which determines the time needed for the airguns to be
recharged. Seismic data acquisition would be conducted 24 hours per
day.
[[Page 40008]]
Receivers and Recording Units
The survey area in Simpson Lagoon has water depths of 0 to 9 ft (0
to 3 m) between the shore and barrier islands and 3 to 45 ft (1 to 15
m) depths north of the barrier islands. Because different types of
receivers would be used for different habitats, the survey area is
categorized by the terms onshore, islands, surf-zone and offshore.
Onshore is the area from the coastline inland. Islands are the barrier
islands. Surf zone is the 0 to 6 ft (0 to 2 m) water depths along the
onshore coastline. Offshore is defined as depths of 3 ft (1 m) or more.
There is a zone between 3 and 6 ft (1 and 2 m) which may be categorized
both as surf zone and as offshore.
The receivers that would be deployed in water consist of multiple
hydrophones and recorder units (Field Digitizing Units or FDUs) placed
on Sercel ULS cables. Approximately 5,000 hydrophones would be
connected to the ULS cable at a minimum of 82.5 ft (27.5 m) intervals
and secured to the ocean bottom cable. Surface markers and acoustic
pingers will be attached to the cable at various intervals to ensure
that the battery packs can be located and retrieved when needed and to
determine exact positions for the hydrophones. This equipment would be
deployed and retrieved with cable boats. The data received at each FDU
would be transmitted through the cables to a recorder for further
processing. This recorder will be installed on a boat-barge combination
and positioned close to the area where data are being acquired. While
recording, the boat- barge combination is stationary and expected to
utilize a two or four point anchoring system.
In the surf-zone, receivers (hydrophones or geophones) would be
bored or flushed up to 12 ft (4 m) below the seabed. These receivers
will transmit data through a cable (as described above) and have an
attached line to facilitate retrieval after recording is completed.
Autonomous recorders (nodes) would be used onshore and on the
islands. The node is located on the ground and its geophone would be
inserted into the ground by hand with the use of a planting pole.
Deployment of the autonomous receiver units would be done by a lay-out
crew on the ground using helicopters for personnel and equipment
transport and/or approved summer travel vehicles (onshore) and a
support boat (for the islands). Data from nodes can be remotely
retrieved from a distance (up to a kilometer). Retrieval of data may be
from a boat or a helicopter. Equipment would be picked up after
recording is complete.
Survey Design
The total area of the proposed seismic survey is approximately 110
mi\2\, which includes onshore, surf-zone, barrier islands, and offshore
(see Figure 1.2 of the BP's IHA application). For the proposed survey,
the receiver cables with hydrophones and recording units would be
oriented in an east-west direction. A total of approximately 44
receiver lines would be deployed at the seafloor with 1,100-1,650 ft
(367-550 m) line spacing. Total receiver line length would be
approximately 500 miles (825 km). The source vessel would travel
perpendicular over the offshore receiver cables along lines oriented in
a north-south direction. These lines would have a length of
approximately 3.75 miles (6.2 km) and a minimum spacing of 660 ft (220
m). The total length of all source lines is approximately 4,000 miles
(6,600 km), including line turns.
The position of each receiver deployed onshore, in the surf zone
and on the barrier islands will be determined using Global Positioning
System (GPS) positioning units. Due to the variable bathymetry of the
survey area, determining positions of receivers deployed in water may
require more than one technique. A combination of Ocean Bottom Receiver
Location (OBRL), GPS and acoustic pingers will be used. For OBRL, the
source vessel fires a precisely positioned single energy source
multiple times along either side of the receiver cables. Production
data may also be used instead of dedicated OBRL acquisition. Multiple
energy sources are used to triangulate a given receiver position. In
addition, Sonardyne acoustical pingers would be located at
predetermined intervals on the receiver lines. The pingers are located
on the ULS cables and transmit a signal to a transponder mounted on a
vessel. This allows for an interpolation of the receiver locations
between the acoustical pingers on the ULS cable and also serves as a
verification of the OBRL method. The Sonardyne pingers transmit at 19-
36 kHz and have a source level of 188-193 dB re [mu]Pa at 1m.
Vessels and Other Equipment
The proposed Simpson Lagoon OBC seismic survey would involve 14 to
16 vessels, as listed in Table 1 below.
Table 1--Summary of Number and Type of Vessels Involved in the Proposed Simpson Lagoon OBC Seismic Survey
[The dimensions provided are approximate]
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Vessel type Number Dimensions Main activity Frequency
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Source Vessel: Main............. 2 71 x 20 ft......... Seismic data acquisition 24-hr operation.
inside and outside
barrier islands.
Source Vessel: Mini............. 1 55 x 15 ft......... Seismic data acquisition 24-hr operation.
inside barrier islands.
Recorder barge with tug boat.... 1 116.5 x 24 ft Seismic data recording.. 24-hr operation.
(barge); 23 x 15
ft (tug).
Cable boats..................... 5-6 42.6 x 13 ft....... Deploy and retrieve 24-hr operation.
receiver cables (with
hydrophones/geophones).
Crew transport vessels.......... 2 44 x 14 ft......... Transport crew and Intermittently,
supplies to and from minimum every 8
the working vessels. hours.
Shallow water crew and support 2-3 34 x 10.5 ft....... Transport 2-5 people and Intermittently.
boats. small amounts of gear
for the boats operating
in the shallower parts
of the survey area.
HSSE vessel..................... 1 38 x 15 ft......... Support SSV As required.
measurements, HSSE
(health, safety,
security, and
environmental)
compliance.
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[[Page 40009]]
To deploy and retrieve receivers in water depths less than those
accessible by the cable boats (surf-zone), equipment such as airboats,
buggies or an Arktos (amphibious craft) and/or Jon boats may be used.
Helicopters and/or approved tundra travel vehicles would be used for
deployment of receiver units onshore as well on the barrier islands. In
the case of helicopters being used, the flight altitude would be at
1,500 feet for 3 to 6 times each day during gear deployment and
retrieval on barrier islands and on shore (i.e., for about 14 days in
late July and early August for deployment and for about 14 days
probably after the Cross Island hunt, which typically ends around
September 10).
Vessels and other equipment would be transported to the North Slope
in late May/early June by trucks. Equipment would be staged at the
CGGVeritas pad for preparation. Vessel preparation would include
assembly of navigation and source equipment, cable deployment and
retrieval systems and safety equipment. Once assembled, vessels would
be launched at either West Dock or Milne Point. Deployment, retrieval,
navigation and source systems will then be tested near West Dock or in
the project area prior to commencement of operations.
Crew Housing and Transfer
The total number of people that would be involved is about 220,
including crew on boats, camp personnel, mechanics, and management.
There are no accommodations available on the source vessels or cable
boats for the crew directly involved in the seismic operations, so
crews would be changed out every 8 to 12 hours. Two vessels would be
used for crew transfers.
The recorder barge/boat (M/V Alaganik and Hook Point) may
accommodate up to 10 people. The barge portion is dedicated to
recording and staging of cables, hydrophones and batteries and fuelling
operations.
Refueling of vessels would be via other vessels at sea, and from
land based sources located at West Dock and Milne Point Unit following
approved U.S. Coast Guard procedures. Sea states and the vessel's
function will be the determining factors on which method is used.
Dates, Duration and Action Area
BP seeks an incidental harassment authorization for the period July
1 to October 15, 2012. Anticipated duration of seismic data acquisition
is approximately 50 days, depending on weather and other circumstances.
Transportation of vessels to West Dock would occur by road in late May/
early June. It is not anticipated that vessels would need to transit by
sea; however, in case this does occur the transit would take place when
ice conditions allow and in consideration of the spring beluga and
bowhead hunt in the Chukchi Sea.
The project area encompasses 110 mi\2\ in Simpson Lagoon, Beaufort
Sea, Alaska. The approximate boundaries of the total surface area are
between 70[deg]28' N and 70[deg]39' N and between 149[deg]24' W and
149[deg]55' W (Figure 1.2 of BP's IHA application). About 46 mi\2\
(41.8%) of the survey area is located inside the barrier islands in
water depths of 0 to 9 ft (0 to 3 m), and 36 mi\2\ (32.7%) outside the
barrier islands in water depths of 3 to 45 ft (1 to 15 m). The
remaining 28 mi\2\ (25.5%) of the survey area is located on land
(onshore and barrier islands), which is solely being used for
deployment of the receivers. The planned start date of seismic data
acquisition offshore of the barrier islands is July 1, 2012, depending
on the presence of ice. Open water seismic operations can only start
when the project area is ice free (i.e. < 10% ice coverage), which in
this area normally occurs around mid-July ( 14 days).
However, BP will not start seismic surveys with airgun operations
within the barrier islands before July 25, 2012. Limited layout of
receiver cables might be possible on land and barrier islands before
the ice has cleared. To limit potential impacts to the bowhead whale
migration and the subsistence hunt, no airgun operations would take
place in the area north of the barrier islands after August 25, 2012.
Surf zone geophone retrieval may continue for a brief period after
airgun operations are complete.
Comments and Responses
A notice of NMFS' proposal to issue an IHA to BP was published in
the Federal Register on May 1, 2012 (77 FR 25830). That notice
described, in detail, BP's proposed activity, the marine mammal species
that may be affected by the activity, and the anticipated effects on
marine mammals and the availability of marine mammals for subsistence
uses. During the 30-day public comment period, NMFS received three
comment letters from the following: The Marine Mammal Commission
(Commission), the Alaska Eskimo Whaling Commission (AEWC), and ten
private citizens, and a petition letter requesting denial of BP's IHA
application.
Any comments specific to BP's application that address the
statutory and regulatory requirements or findings NMFS must make to
issue an IHA are addressed in this section of the Federal Register
notice.
Comment 1: The Commission and AEWC recommended that NMFS continue
to include proposed incidental harassment authorization language at the
end of Federal Register notices but ensure that the language is
consistent with that referenced in the main body of the Federal
Register notice.
Response: NMFS agrees that this is a good recommendation and will
try to include proposed incidental harassment authorization language at
the end of Federal Register notices if there is sufficient time
allowing for drafting the IHA language before the proposed IHA Federal
Register notice is issued. NMFS will also try to ensure that the
language is consistent with that referenced in the main body of the
Federal Register notice.
Comment 2: The Commission recommends NMFS use species-specific
maximum density estimates or average estimates adjusted by a
precautionary correction factor as a basis for (1) estimating the
expected number of takes and (2) making its determination regarding
whether the total taking would have a negligible impact on the species
or stocks. Further, the Commission points out that NMFS used Brandon et
al. (2011) data for bowhead whale density estimates but not for belugas
summer density of 0.0018 whales/km\2\. The Commission questions why
NMFS uses the summer density estimate for belugas of 0.0008 whales/
km\2\, which was derived from aerial surveys conducted in 1982 to 1986
(Moore et al. 2000).
Response: To provide some allowance for the uncertainties, BP
calculated both ``maximum estimates'' as well as ``average estimates''
of the numbers of marine mammals that could potentially be affected.
For a few marine mammal species, several density estimates were
available, and in those cases the mean and maximum estimates were
determined from the survey data. In other cases, no applicable estimate
(or perhaps a single estimate) was available, so adjustments were used
to arrive at ``average'' and ``maximum'' estimates. The species-
specific estimation of these numbers is provided in the Federal
Register notice for the proposed IHA (77 FR 25830; May 1, 2012). NMFS
has determined that the average density data of marine mammal
populations will be used to calculate estimated take numbers because
these numbers are based on surveys and monitoring of marine mammals in
the vicinity of the proposed project area. For several species whose
average densities are too low to yield a take number due to extra-
[[Page 40010]]
limital distribution in the vicinity of the proposed Beaufort Sea
survey area, but whose chance occurrence has been documented in the
past, such as gray and killer whales and harbor porpoises, NMFS
allotted a few numbers of these species to allow unexpected takes of
these species.
The determination regarding whether the total taking would have a
negligible impact on the species or stocks is based on the species-
specific average density, or based on allotted number from past chance
occurrence, as described above and in the proposed Federal Register
notice for the proposed IHA (77 FR 25830).
Regarding the reason for using older data for beluga whales summer
density, there were several reasons for using the data reported in
Moore et al. (2000):
(1) It has been common practice to use data published in peer
reviewed journals if these are available for the area and time period
of the proposed activity.
(2) Since the Simpson Lagoon seismic survey data will take place
mainly in water depths of <=10 m, the data from 11,985 km of effort
collected in water depths of <=50 m (Moore et al. 2000) was thought to
be the most representative.
Comment 3: The Commission requested NMFS provide additional
justification for its preliminary determination that the proposed
monitoring program will be sufficient to detect, with a high level of
confidence, all marine mammals within or entering the identified
exclusion and disturbance zones.
Response: The proposed visual monitoring measures for open water
seismic and geophysical surveys is a standard mitigation method used by
industry and research institutes to reduce potential impacts to marine
mammals that might be present in the vicinity of the action area.
However, as noted in the Federal Register notice for the proposed IHA,
there is no guarantee that all marine mammals within or entering the
identified exclusion and disturbance zones would be immediately
detected. Monitoring reports from the past have indicated that
individual marine mammals have been found within the exclusion zone
during the survey, which prompted timely power-down and shut down of
seismic airguns. Other means to reduce marine mammal injury and TTS
include pre-activity ramp-up and restricting cold start during darkness
and inclement weather when the entire 180-dB zone is not visible
without using night vision devices (NVDs) and/or forward looking
infrared (FLIR). Therefore, although there is no guarantee that all
marine mammals within or entering the identified exclusion zones would
be immediately detected, NMFS is confident that it is very unlikely a
marine mammal could be injured or receive TTS from exposure to a
seismic impulse.
Comment 4: The Commission recommends NMFS restrict the commencement
of ramp-up from a full shut-down at night or in periods of poor
visibility, regardless of whether the entire 180-dB re 1 [mu]Pa
exclusion zone is visible. The Commission states that it is questioning
the effectiveness of using vessel lights, night vision devices, and/or
forward looking infrared to monitor the exclusion zones prior to ramp-
up procedures at night or in periods of poor visibility.
Response: NMFS agrees with the Commission's recommendation that no
ramp-up from a full shut-down should occur at night or in periods of
poor visibility. NMFS further clarified with the Commission that if the
entire 180-dB exclusion zone is not visible without using vessel
lights, night vision devices, and/or forward looking infrared, then BP
should not ramp up from a full shut-down. However, if the entire 180-dB
zone is visible without using these devices, then a ramp-up from the
full shut-down can be commenced.
Comment 5: The Commission recommends that NMFS specify reduced
vessel speeds of 9 knots or less when whales are within 300 m or when
weather conditions reduce visibility.
Response: NMFS agrees with the Commission's recommendation that
vessels should reduce speed to 9 knots or less when weather conditions
reduce visibility. NMFS has specified this additional condition in the
final IHA issued to BP. Consistent with the proposed IHA, NMFS is also
requiring BP to reduce vessel speed to less than 5 knots within 300
yards (900 feet or 274 m) of any whale(s).
Comment 6: The Commission recommends that NMFS require BP to report
injured and dead marine mammals to NMFS and local stranding network
using NMFS' phased approach to reporting, as outlined in the proposed
incidental harassment authorization language at the end of the Federal
Register notice for the proposed IHA (77 FR 25830; May 1, 2012).
Response: NMFS agrees with and is implementing the Commission's
recommendation.
Comment 7: The AEWC states that it is not clear on the limitation
on geophysical activity inside the barrier islands prior to July 25th.
The AEWC states that the activities proposed by BP are governed by
Section 502(a)(2)(A) of the Conflict Avoidance Agreement (CAA), and
that BP is not to conduct geophysical activity inside the barrier
islands prior to July 25, 2012. However, the AEWC points out that the
Federal Register notice for the proposed IHA (77 FR 25830; May 1, 2012)
only poses restrictions on BP's seismic activities after August 25,
2012, outside the barrier islands.
Response: After clarifying with BP, NMFS confirmed that BP will not
conduct seismic surveys using airguns within the barrier islands prior
to July 25, 2012, as agreed in the CAA. NMFS has included this
additional condition in the final IHA issued to BP.
Comment 8: The AEWC recommends NMFS consider incorporating an
alternative based off of the CAA process into the final Effects of Oil
and Gas Activities in the Arctic Ocean Environmental Impact Statement
(EIS) on the effects of oil and gas activities in the Arctic Ocean, as
they requested in their comments, and this IHA provides an example of
how the process can and should function properly to the benefit of the
local community, offshore operators, and the federal government.
Response: This recommendation is not directly related to the
issuance of the IHA to BP for the take of marine mammals incidental to
its OBC seismic survey in the Simpson Lagoon area of the Beaufort Sea.
However, NMFS will continue to work with the AEWC, other Alaska Native
marine mammal commissions, and other stakeholders on this issue and
others during preparation of the Environmental Impact Statement.
Comment 9: The AEWC states that NMFS's preliminary decision of not
requiring BP to have PAM is questionable because the issue of acoustic
monitoring has been on the table for many years. AEWC supports the peer
review recommendation that PAM needs to be included to monitor for
calling marine mammals, and to evaluate calling rates relative to
seismic operations or received levels of seismic sounds.
Response: NMFS does not agree with the AEWC's recommendation. The
Simpson Lagoon project was designed to avoid the use of airguns outside
of the barrier islands during the bowhead whale migration. Because
airgun use will be restricted to areas inside the barrier islands
during the bowhead migration north of Simpson Lagoon, and because the
barrier islands block much of the sound from airguns and the depths
inside the barrier islands are not sufficient to efficiently carry the
long wavelength (low frequency) sounds that dominate airgun spectra,
sounds above 120 dB are not expected to reach the
[[Page 40011]]
migration corridor when whales are present. While methods using
directional hydrophones to localize whale calls can offer a powerful
means of detecting subtle changes in whale call distributions related
to industrial activities, the sounds being introduced by the Simpson
Lagoon project during the migration will be weak and the number of days
of exposure will be small. With that in mind, operations such as that
at Simpson Lagoon would be very unlikely to add anything to our
understanding of bowhead whale responses to industrial sounds. Other
work that has already been completed (such as the work at Northstar
Island for sounds associated with production and the work done by Shell
and others to assess responses to airgun sounds) have the capacity to
add to our understanding of bowhead whale responses to industrial
sounds, but the circumstances surrounding the Simpson Lagoon project
suggest that it would fail to produce meaningful (statistically
significant) results.
Because of doubts regarding the value of an acoustic localization
study undertaken in association with the Simpson Lagoon project, and
because timing would have made study design and implementation
challenging, BP explored other opportunities to contribute to our
collective understanding of potential acoustic impacts in the Beaufort
Sea. Although BP measured sound field propagation through barrier
islands during its 2008 Liberty seismic operation, the company proposed
to undertake recordings that will yield more data regarding propagation
of airgun sounds in the presence of barrier islands and shallow water.
That work is currently planned to occur during the Simpson Lagoon
seismic operation.
Comment 10: Five private citizens requested NMFS deny BP's IHA
application due to concerns about the potential for an oil spill.
Response: As described in detail in the Federal Resister notice for
the proposed IHA (77 FR 28530; May 1, 2012), BP's proposed Simpson
Lagoon project would only involve OBC seismic surveys using airguns and
ocean bottom recorders. There will be no oil and gas related drilling
or production.
Comment 11: Six private citizens request NMFS deny BP's IHA
application because they think seismic impulse would kill marine
mammals in the area.
Response: As described in detail in the Federal Resister notice for
the proposed IHA (77 FR 28530; May 1, 2012), as well as in this
document, NMFS does not believe that BP's Simpson Lagoon OBC seismic
surveys would cause injury or mortality to marine mammals. The required
monitoring and mitigation measures being implemented would further
reduce the adverse effect on marine mammals to the lowest levels
practicable. Therefore, NMFS expects that only a small number of marine
mammals would be taken by Level B harassment in the forms of temporary
behavioral modification and displacement from the survey area. No
injury and/or mortality of marine mammals is expected, and none was
authorized.
Comment 12: One private citizen requested NMFS deny BP's IHA
application for fear that intensive sound could cause mortality to
cephalopods and other invertebrates, which are important prey for
marine mammals. Citing Andre et al. (2011), this person states that
immediately following exposure to low frequency sound, the cephalopods
showed hair cell damage within the statocysts. Overy time, nerve fibers
became swollen and, eventually, large holes appeared.
Response: NMFS is aware of the paper by Andre et al. (2011), which
was published in the journal Frontier of Ecology and the Environment.
However, NMFS does not believe the results of the study represent what
would happen in a natural environment. In their experiment, Andre et
al. (2011) used 50-400 Hz sinusoidal wave sweeps with 100% duty cycle
and 1-second sweep period for 2 hours in either a 2.000-liter
fiberglass reinforced plastic tank or a 200-liter (glass-walled) tank
occupied by one individual of one of the four cephalopod species. The
sweep was produced and amplified through an in-air loudspeaker, while
the level received was measured by a calibrated B&K 8106 hydrophone
(received sound pressure level: 157 5 dB re 1 [mu]Pa, with
peak levels at 175 dB re 1 [mu]Pa). Therefore, the cephalopod in the
small tank was exposed to a long-lasting intensive standing wave,
instead of propagating waves from short airgun impulses in a free
field. In addition, there was no mention of the total sound exposure
level (SEL) over the 2-hour exposure period. For these reasons, NMFS
did not consider this study in the analysis of acoustic impacts to
marine mammal habitat, including prey species.
Description of Marine Mammals in the Area of the Specified Activity
The marine mammal species under NMFS jurisdiction most likely to
occur in the seismic survey area include three cetacean species, beluga
(Delphinapterus leucas), bowhead whales (Balaena mysticetus), and gray
whales (Eschrichtius robustus), and three pinniped species, ringed
(Phoca hispida), spotted (P. largha), and bearded seals (Erignathus
barbatus).
Four additional cetacean species and one pinniped species: Harbor
porpoise (Phocoena phocoena), killer whale (Orcinus orca), humpback
whale (Megaptera novaeangliae) and minke whale (Balaenoptera
acutorostrata), and Ribbon seals (Histriophoca fasciata) could also
occur in the project area. Though their occurrence is considered
extralimital.
The bowhead and humpback whales are listed as ``endangered'' under
the Endangered Species Act (ESA) and as depleted under the MMPA.
Certain stocks or populations of gray and beluga whales and spotted
seals are listed as endangered or proposed for listing under the ESA;
however, none of those stocks or populations occur in the proposed
activity area. Additionally, the ribbon seal is considered a ``species
of concern'', meaning that NMFS has some concerns regarding status and
threats to this species, but for which insufficient information is
available to indicate a need to list the species under the ESA. Bearded
and ringed seals are ``candidate species'' under the ESA, meaning they
are currently being considered for listing.
BP's application contains information on the status, distribution,
seasonal distribution, and abundance of each of the species under NMFS'
jurisdiction mentioned. Please refer to the application for that
information (see ADDRESSES). Additional information can also be found
in the NMFS Stock Assessment Reports (SAR). The Alaska 2011 SAR is
available at: http://www.nmfs.noaa.gov/pr/pdfs/sars/ak2011.pdf.
Potential Effects of the Specified Activity on Marine Mammals
Operating active acoustic sources such as airgun arrays, pinger
systems, and vessel activities have the potential for adverse effects
on marine mammals.
Potential Effects of Airgun Sounds on Marine Mammals
The effects of sounds from airgun pulses might include one or more
of the following: Tolerance, masking of natural sounds, behavioral
disturbance, and temporary or permanent hearing impairment or non-
auditory effects (Richardson et al. 1995). As outlined in previous NMFS
documents, the effects of noise on marine mammals are highly variable.
The Notice of Proposed IHA (77 FR 28530; May 1, 2012) included a
discussion of the effects of airguns on
[[Page 40012]]
marine mammals, which is not repeated here. That discussion did not
take into consideration the monitoring and mitigation measures proposed
by BP and NMFS. No cases of temporary threshold shift (TTS) are
expected as a result of BP's activities given the small size of the
source, the strong likelihood that baleen whales (especially migrating
bowheads) would avoid the approaching airguns (or vessel) before being
exposed to levels high enough for there to be any possibility of TTS,
and the mitigation measures required to be implemented during the
survey described later in this document. Based on the fact that the
sounds produced by BP's operations are unlikely to cause TTS in marine
mammals, it is extremely unlikely that permanent hearing impairment
would result. No injuries or mortalities are anticipated as a result of
BP's operations, and none are authorized to occur. Only Level B
harassment is anticipated as a result of BP's activities.
Potential Effects of Pinger Signals
A pinger system (Sonardyne Acoustical Pingers) and acoustic
releases/transponders would be used for BP's 2012 open water OBC
seismic survey in the Beaufort Sea. The specifications of this pinger
system (source levels and frequency ranges) were provided in the Notice
of Proposed IHA (77 FR 28530; May 1, 2012). The source levels of the
pinger are much lower than those of the airguns, which are discussed
above. It is unlikely that the pinger produces pulse levels strong
enough to cause temporary hearing impairment or (especially) physical
injuries even in an animal that is (briefly) in a position near the
source.
Anticipated Effects on Habitat
The primary potential impacts to marine mammals and other marine
species are associated with elevated sound levels produced by airguns
and other active acoustic sources. However, other potential impacts to
the surrounding habitat from physical disturbance are also possible.
Potential Impacts on Prey Species
With regard to fish as a prey source for cetaceans and pinnipeds,
fish are known to hear and react to sounds and to use sound to
communicate (Tavolga et al. 1981) and possibly avoid predators (Wilson
and Dill 2002). Experiments have shown that fish can sense both the
strength and direction of sound (Hawkins 1981). Primary factors
determining whether a fish can sense a sound signal, and potentially
react to it, are the frequency of the signal and the strength of the
signal in relation to the natural background noise level.
The level of sound at which a fish will react or alter its behavior
is usually well above the detection level. Fish have been found to
react to sounds when the sound level increased to about 20 dB above the
detection level of 120 dB (Ona 1988); however, the response threshold
can depend on the time of year and the fish's physiological condition
(Engas et al. 1993). In general, fish react more strongly to pulses of
sound rather than a continuous signal (Blaxter et al. 1981), and a
quicker alarm response is elicited when the sound signal intensity
rises rapidly compared to sound rising more slowly to the same level.
Investigations of fish behavior in relation to vessel noise (Olsen
et al. 1983; Ona 1988; Ona and Godo 1990) have shown that fish react
when the sound from the engines and propeller exceeds a certain level.
Avoidance reactions have been observed in fish such as cod and herring
when vessels approached close enough that received sound levels are 110
dB to 130 dB (Nakken 1992; Olsen 1979; Ona and Godo 1990; Ona and
Toresen 1988). However, other researchers have found that fish such as
polar cod, herring, and capelin are often attracted to vessels
(apparently by the noise) and swim toward the vessel (Rostad et al.
2006). Typical sound source levels of vessel noise in the audible range
for fish are 150 dB to 170 dB (Richardson et al. 1995).
Some mysticetes, including bowhead whales, feed on concentrations
of zooplankton. Some feeding bowhead whales may occur in the Alaskan
Beaufort Sea in July and August, and others feed intermittently during
their westward migration in September and October (Richardson and
Thomson [eds.] 2002; Lowry et al. 2004). However, by the time most
bowhead whales reach the Chukchi Sea (October), they will likely no
longer be feeding, or if it occurs it will be very limited. A reaction
by zooplankton to a seismic impulse would only be relevant to whales if
it caused concentrations of zooplankton to scatter. Pressure changes of
sufficient magnitude to cause that type of reaction would probably
occur only very close to the source. Impacts on zooplankton behavior
are predicted to be negligible, and that would translate into
negligible impacts on feeding mysticetes. Thus, the activity is not
expected to have any habitat-related effects that could cause
significant or long-term consequences for individual marine mammals or
their populations.
Potential Impacts on Availability of Affected Species or Stock for
Taking for Subsistence Uses
Seismic surveys have the potential to impact marine mammals hunted
by Native Alaskans. In the case of cetaceans, the most common reaction
to anthropogenic sounds (as noted previously in this document) is
avoidance of the ensonified area. In the case of bowhead whales, this
often means that the animals could divert from their normal migratory
path by up several kilometers. Additionally, general vessel presence in
the vicinity of traditional hunting areas could negatively impact a
hunt.
In the case of subsistence hunts for bowhead whales in the Beaufort
Sea, there could be an adverse impact on the hunt if the whales were
deflected seaward (further from shore) in traditional hunting areas.
The impact would be that whaling crews would have to travel greater
distances to intercept westward migrating whales, thereby creating a
safety hazard for whaling crews and/or limiting chances of successfully
striking and landing bowheads.
The proposed seismic survey would take place between July and
September. The project area is located approximately 35 miles northeast
from Nuiqsut, 35 miles west from Cross Island, 150 miles west from
Kaktovik and 180 miles east from Barrow. Potential impact from the
planned activities is expected mainly from sounds generated by the
vessel and during active airgun deployment. Due to the timing of the
project and the distance from the surrounding communities, it is
anticipated to have no effects on spring harvesting and little or no
effects on the occasional summer harvest of beluga whale, subsistence
seal hunts (ringed and spotted seals are primarily harvested in winter
while bearded seals are hunted during July-September in the Beaufort
Sea), or the fall bowhead hunt. The community of Nuiqsut may begin fall
whaling activities in late August to early September from Cross Island
(east of the survey area), and their efforts are typically focused on
whales approaching Cross Island so that any harvest would occur before
whales approached the survey area. As part of the planned mitigation
measures (see below), BP will not start airgun operations within the
barrier islands before July 25, 2012, and plans to complete those
portions of the survey area outside of the barrier islands prior to
August 25, 2012. All seismic activities after this date would take
[[Page 40013]]
place inshore of the barrier islands, thus avoiding the subsistence
bowhead hunt in the area.
Finally, BP has signed a Conflict Avoidance Agreement (CAA), and
prepared a Plan of Cooperation (POC) under 50 CFR 216.104 to address
potential impacts on subsistence hunting activities. The CAA identifies
what measures have been or will be taken to minimize adverse impacts of
the planned activities on subsistence harvesting. BP met with the AEWC
and communities' Whaling Captains' Associations as part of the CAA
development, and established avoidance guidelines and other mitigation
measures to be followed where the activities may have an impact on
subsistence.
Mitigation Measures
In order to issue an incidental take authorization 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 on the availability of such species
or stock for taking for certain subsistence uses.
For the BP open-water seismic survey in the Beaufort Sea, NMFS is
requiring BP to implement the following mitigation measures to minimize
the potential impacts to marine mammals in the project vicinity as a
result of the marine seismic survey activities.
The mitigation measures are divided into the following major
groups: (1) Sound source measurements, (2) Establishing exclusion and
disturbance zones, (3) Vessel and helicopter related mitigation
measures, and (4) Mitigation measures for airgun operations. The
primary purpose of these mitigation measures is to detect marine
mammals within, or about to enter designated exclusion zones and to
initiate immediate shutdown or power down of the airgun(s), therefore
it's very unlikely potential injury or TTS to marine mammals would
occur, and Level B behavioral of marine mammals would be reduced to the
lowest level practicable.
(1) Sound Source Measurements
The acoustic monitoring program has two objectives: (1) To verify
the modeled distances to the exclusion and disturbance zones from the
640 in\3\ and 320 in\3\ airgun arrays and to provide corrected
distances to the PSOs; and (2) to measure vessel sounds (i.e., received
levels referenced to 1 m from the sound source) of each representative
vessel of the seismic fleet, to obtain information on the sounds
produced by these vessels.
Verification and Establishment of Exclusion and Disturbance Zones
Acoustic measurements to calculate received sound levels as a
function of distance from the airgun sound source will be conducted
within 72 hours of initiation of the seismic survey. These measurements
will be conducted according to a standard protocol for the 640-in\3\
array, the 320-in\3\ array and the 40-in\3\ gun, both inside and
outside the barrier islands.
The results of these acoustic measurements will be used to re-
define, if needed, the distances to received levels of 190, 180, 160
and 120 dB. The distances of the received levels as a function of the
different sound sources (varying discharge volumes) will be used to
guide power-down and ramp-up procedures. A preliminary report
describing the methodology and results of the verification for at least
the 190 dB and 180 dB (rms) exclusion zones will be submitted to NMFS
within 14 days of completion of the measurements.
Measurements of Vessel Sounds
BP intends to measure vessel sounds of each representative vessel.
The exact scope of the source level measurements (back-calculated as
received levels at 1 m from the source) will follow a pre-defined
protocol to eliminate the complex interplay of factors that underlie
such measurements, such as bathymetry, vessel activity, location,
season, etc. Where possible and practical the monitoring protocol will
be developed in alignment with other existing vessel source level
measurements.
(2) Establishing Exclusion and Disturbance Zones
Under current NMFS guidelines, the ``exclusion zone'' for marine
mammal exposure to impulse sources is customarily defined as the area
within which received sound levels are >=180 dB re 1 [mu]Pa (rms) for
cetaceans and >=190 dB re 1 [mu]Pa (rms) for pinnipeds. These safety
criteria are based on an assumption that SPL received at levels lower
than these will not injure these animals or impair their hearing
abilities, but that at higher levels might have some such effects.
Disturbance or behavioral effects to marine mammals from underwater
sound may occur after exposure to sound at distances greater than the
exclusion zones (Richarcdson et al. 1995).
An acoustic propagation model, i.e., JASCO's Marine Operations
Noise Model (MONM), was used to estimate the distances to received
sound levels of 190, 180, 170, 160, and 120 dB re 1[mu]Pa (rms) for
pulsed sounds from the 640-in\3\ and 320-in\3\ airgun arrays. Modeling
methodology and results are described in detail in the appendix of the
BP's IHA application (Warner and Hipsey 2011). Table 2 summarizes the
distances from the source to specific received sound levels based on
MONM modeling.
Table 2--Estimated Distances to Specified Received SPL (rms) From Airgun Arrays With a Total Discharge Volume of 640-in\3\, 320-in\3\, and 40-in\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Distance in meters (inside barrier islands) Distance in meters (outside
------------------------------------------------------ barrier islands)
Received Levels (dB re 1 [mu]Pa rms) -----------------------------------
640-in\3\ 320-in\3\ 40-in\3\ 640-in\3\ 40-in\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
190........................................................... 310 160 16 120 <50
180........................................................... 750 480 59 950 <50
170........................................................... 1,200 930 300 2,500 120
160........................................................... 1,800 1,500 700 5,500 810
120........................................................... 6,400 5,700 3,700 44,000 16,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Values are based on 2 m-tow depth for the 640-in\3\ and 40-in\3\ array, and a 1 m-tow depth for the 320-in\3\ array.
The distances to received sound levels of 160 dB re 1 [mu]Pa (rms)
of the 640-in\3\ airgun array were used to calculate the numbers of
marine mammals potentially harassed by the activities. The distances to
received
[[Page 40014]]
levels of 180 dB and 190 dB re 1 [mu]Pa (rms) are mainly relevant as
exclusion radii to avoid level A harassment of marine mammals through
implementation of shut down and power down measures (see details
below).
(3) Vessel and Helicopter Related Mitigation Measures
This proposed mitigation measures apply to all vessels that are
part of the Simpson Lagoon seismic survey, including crew transfer
vessels.
Vessel operators shall avoid concentrations or groups of
whales and vessels shall not be operated in a way that separates
members of a group. In proximity of feeding whales or aggregations,
vessel speed shall be less than 10 knots.
When within 900 feet (300 m) of whales vessel operators shall
take every effort and precaution to avoid harassment of these animals
by:
[cir] Reducing speed to 5 knots or less when within 300 yards of
whales and steering around (groups of) whales if circumstances allow,
but never cutting off a whale's travel path;
[cir] Avoiding multiple changes in direction and speed.
Vessel operators shall check the waters immediately adjacent
to a vessel to ensure that no marine mammals will be injured when the
vessel's propellers (or screws) are engaged.
To minimize collision risk with marine mammals, vessels shall
not be operated at speeds that would make collisions with whales
likely. When weather conditions require, such as when visibility drops,
vessels shall reduce speed to 9 knots or below to avoid the likelihood
of injury to whales.
Sightings of dead marine mammals would be reported immediately
to the BP representative. BP is responsible for ensuring reporting of
the sightings according to the guidelines provided by NMFS.
In the event that any aircraft (such as helicopters) are used
to support the planned survey, the mitigation measures below would
apply:
[cir] Under no circumstances, other than an emergency, shall
aircraft be operated at an altitude lower than 1,000 feet above sea
level (ASL) when within 0.3 mile (0.5 km) of groups of whales.
[cir] Helicopters shall not hover or circle above or within 0.3
mile (0.5 km) of groups of whales.
(4) Mitigation Measures for Airgun Operations
The primary role for airgun mitigation during seismic survey is to
monitor marine mammals near the seismic source vessel during all
daylight airgun operations and during any nighttime start-up of the
airguns. During the seismic survey PSOs will monitor the pre-
established exclusion zones for the presence of marine mammals. When
marine mammals are observed within, or about to enter, designated
safety zones, PSOs have the authority to call for immediate power down
(or shutdown) of airgun operations as required by the situation. A
summary of the procedures associated with each mitigation measure is
provided below.
Ramp Up Procedure
Ramp up procedures for an airgun array involve a step-wise increase
in the number of operating airguns until the required discharge volume
is achieved. The purpose of a ramp up (sometimes also referred to as
soft start) is to provide marine mammals in the vicinity of the
activity the opportunity to leave the area and thus avoid any potential
injury or impairment of their hearing abilities.
The rate of ramp up shall be no more than 6 dB of source level per
5-min period.
A common procedure is to double the number of operating airguns at
5-min intervals, starting with the smallest gun in the array. BP states
that it intends to double the number of airguns operating at 5 minute
intervals during ramp up. For the 640-cu-in airgun array of the Simpson
Lagoon seismic survey this is estimated to take 20 minutes, and for the
320-in\3\ array 15 minutes. During ramp up, the safety zone for the
full airgun array will be observed.
The ramp up procedures will be applied as follows:
A ramp up, following a cold start, can be applied if the
exclusion zone has been free of marine mammals for a consecutive 30-
minute period. The entire exclusion zone must have been visible during
these 30 minutes. If the entire exclusion zone is not visible, then
ramp up from a cold start cannot begin.
Ramp up procedures from a cold start will be delayed if a
marine mammal is sighted within the exclusion zone during the 30-minute
period prior to the ramp up. The delay will last until the marine
mammal(s) has been observed to leave the exclusion zone or until the
animal(s) is not sighted for at least 15 or 30 minutes. The 15 minutes
applies to small toothed whales and pinnipeds, while a 30 minute
observation period applies to baleen whales and large toothed whales.
A ramp up, following a shutdown, can be applied if the
marine mammal(s) for which the shutdown occurred has been observed to
leave the exclusion zone or until the animal(s) is not sighted for at
least 15 minutes (small toothed whales and pinnipeds) or 30 minutes
(baleen whales and large toothed whales). This assumes there was a
continuous observation effort prior to the shutdown and the entire
exclusion zone is visible.
If, for any reason, electrical power to the airgun array
has been discontinued for a period of 10 minutes or more, ramp-up
procedures need to be implemented. Only if the PSO watch has been
suspended, a 30-minute clearance of the exclusion zone is required
prior to commencing ramp-up. Discontinuation of airgun activity for
less than 10 minutes does not require a ramp-up.
The seismic operator and PSOs will maintain records of the
times when ramp-ups start and when the airgun arrays reach full power.
Power-Down Procedures
A power down is the immediate reduction in the number of operating
airguns such that the radii of the 190 dB and 180 dB (rms) zones are
decreased to the extent that an observed marine mammal is not in the
applicable safety zone of the full array. During a power down, one
airgun (or some other number of airguns less than the full airgun
array) continues firing. The continued operation of one airgun is
intended to (a) alert marine mammals to the presence of airgun
activity, and (b) retain the option of initiating a ramp up to full
operations under poor visibility conditions.
The airgun array shall be immediately powered down
whenever a marine mammal is sighted approaching close to or within the
applicable exclusion zone of the full array, but is outside the
applicable exclusion zone of the single mitigation airgun.
If a marine mammal is already within the exclusion zone
when first detected, the airguns will be powered down immediately.
Following a power-down, ramp up to the full airgun array
will not resume until the marine mammal has cleared the exclusion zone.
The animal will be considered to have cleared the exclusion zone if it
is visually observed to have left the exclusion zone of the full array,
or has not been seen within the zone for 15 minutes (pinnipeds or small
toothed whales) or 30 minutes (baleen whales or large toothed whales).
[[Page 40015]]
Shutdown Procedures
The operating airgun(s) will be shutdown completely if a
marine mammal approaches or enters the 190 or 180 dB (rms) exclusion
zone of the smallest airgun.
Airgun activity will not resume until the marine mammal
has cleared the exclusion zone of the full array. The animal will be
considered to have cleared the exclusion zone as described above under
ramp up procedures.
Poor Visibility Conditions
BP plans to conduct 24-hour operations. PSOs will not be on duty
during ongoing seismic operations during darkness, given the very
limited effectiveness of visual observation at night (there will be no
periods of darkness in the survey area until mid-August). The proposed
provisions associated with operations at night or in periods of poor
visibility include the following:
If during foggy conditions, heavy snow or rain, or
darkness (which may be encountered starting in late August), the full
180 dB exclusion zone is not visible without using vessel lights, night
vision devices, and/or forward looking infrared, the airguns cannot
commence a ramp-up procedure from a full shut-down.
If one or more airguns have been operational before
nightfall or before the onset of poor visibility conditions, they can
remain operational throughout the night or poor visibility conditions.
In this case ramp-up procedures can be initiated, even though the
exclusion zone may not be visible, on the assumption that marine
mammals will be alerted by the sounds from the single airgun and have
moved away.
In addition, airguns shall not be fired during long transits when
exploration activities are not occurring, including the common firing
of one airgun (also referred to as the ``mitigation gun'' in past
IHAs). This does not apply to turns when starting a new track line.
Keeping an airgun firing unnecessarily for long periods of time would
only introduce more noise into the water.
Mitigation Measures for Subsistence Activities
(1) Subsistence Mitigation Measures
To limit potential impacts to the bowhead whale migration and the
subsistence hunt, BP would not conduct airgun operations inside the
barrier islands before July 25, and will not conduct airgun operations
in the area north of the barrier islands after 25 August.
(2) Plan of Cooperation (POC) and Conflict Avoidance Agreement (CAA)
Regulations at 50 CFR 216.104(a)(12) require IHA applicants for
activities that take place in Arctic waters to provide a POC or
information that identifies what measures have been taken and/or will
be taken to minimize adverse effects on the availability of marine
mammals for subsistence purposes.
BP has signed a Conflict Avoidance Agreement (CAA) with the Alaska
Eskimo Whaling Commission (AEWC) and communities' Whaling Captains'
Associations for the proposed 2012 Simpson Lagoon OBV seismic survey.
The main purpose of the CAA is to provide (1) equipment and procedures
for communications between subsistence participants and industry
participants; (2) avoidance guidelines and other mitigation measures to
be followed by the industry participants working in or transiting in
the vicinity of active subsistence hunters, in areas where subsistence
hunters anticipate hunting, or in areas that are in sufficient
proximity to areas expected to be used for subsistence hunting that the
planned activities could potentially adversely affect the subsistence
bowhead whale hunt through effects on bowhead whales; and (3) measures
to be taken in the event of an emergency occurring during the term of
the CAA.
In the CAA, BP agrees to employ a Marine Mammal Observer/Inupiat
Communitor (MMO/IC) on board each primary sound source vessel owned or
operated by BP in the Beaufort Sea, and that native residents of the
eleven villages represented by the AEWC shall be given preference in
hiring for MMO/IC positions.
The CAA states that all vessels (operated by BP) shall report to
the appropriate Communication Center (Com-Center) at least once every
six hours commencing with a call at approximately 06:00 hours. The
appropriate Com-Center shall be notified if there is any significant
change in plans, such as an unannounced start-up of operations or
significant deviations from announced course, and such Com-Center shall
notify all whalers of such changes.
The CAA further states that each Com-Center shall have an Inupiat
operator (``Com-Center operator'') on duty 24 hours per day from August
15, or one week before the start of the fall bowhead whale hunt in each
respective village, until the end of the bowhead whale subsistence
hunt.
The CAA also states that following the end of the fall 2012 bowhead
whale subsistence hunt and prior to the 2013 pre-season introduction
meetings, the industry participant that establishes the Deadhorse and
Kaktovik Com Center will offer to the AEWC Chairman to host a joint
meeting with all whaling captains of the villages of Nuiqsut, Kaktovik,
and Barrow, the Marine Mammal Observer/Inupiat Communicators stationed
on the industry participants' vessels in the Beaufort Sea, and with the
Chairman and Exective Director of the AEWC, at a mutually agreed upon
time and place on North Slope of Alaska, to review the results of the
2012 Beaufort Sea open water season.
In addition, BP has developed a ``Plan of Cooperation'' (POC) for
the proposed 2012 seismic survey in the Simpson Lagoon of the Alaskan
Beaufort Sea in consultation with representatives of Nuiqsut Community
on the Beaufort Sea coast on issues related to subsistence seal
hunting. Mitigation measures similar to those listed in the CAA have
been identified in the POC, and a final POC has been delivered to NMFS.
Mitigation Conclusions
NMFS has carefully evaluated these mitigation measures and
considered a range of other measures in the context of ensuring that
NMFS prescribes the means of effecting the least practicable impact on
the affected marine mammal species and stocks and their habitat. Our
evaluation of potential measures included consideration of the
following factors in relation to one another:
The manner in which, and the degree to which, the
successful implementation of the measure is expected to minimize
adverse impacts to marine mammals;
The proven or likely efficacy of the specific measure to
minimize adverse impacts as planned; and
The practicability of the measure for applicant
implementation.
Based on our evaluation of the applicant's proposed measures, as
well as other measures considered by NMFS and proposed by the
independent peer review panel, NMFS has determined that the proposed
mitigation measures provide the means of effecting the least
practicable impact on marine mammal species or stocks and their
habitat, paying particular attention to rookeries, mating grounds, and
areas of similar significance.
Monitoring and Reporting Measures
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
[[Page 40016]]
regulations at 50 CFR 216.104(a)(13) indicate that requests for ITAs
must include the suggested means of accomplishing the necessary
monitoring and reporting that will result in increased knowledge of the
species and of the level of taking or impacts on populations of marine
mammals that are expected to be present in the proposed action area.
Monitoring Measures
(1) Monitoring Measures
The following monitoring measures are required for BP's 2012 open-
water seismic survey in the Beaufort Sea.
There will be two vessel-based monitoring programs during the
Simpson Lagoon OBC seismic survey. One program involves the presence of
protected species observers (PSOs) on the seismic source vessels during
the entire seismic survey period. The other vessel-based program
involves two PSOs on a monitoring vessel outside the barrier islands
after 25 August.
Visual Monitoring From Source Vessels
Two PSOs will be present on each seismic source vessel. Of these
two PSOs, one will be on watch at all times during daylight hours to
monitor the 190 and 180 dB exclusion zones for the presence of marine
mammals during airgun operations. During the fall bowhead whale
migration season the 160 dB disturbance zone will also be monitored for
the presence of groups of 12 or more baleen whales. The 120 dB
disturbance zone for bowhead cow/calf pairs will be monitored from
another vessel (see section ``Visual Monitoring Outside the Barrier
Islands''). The main objectives of the vessel-based marine mammal
monitoring program from the source vessels are as follows:
To implement mitigation measures during seismic operations
(e.g. course alteration, airgun power-down, shut-down and ramp-up);
To record all marine mammal data needed to estimate the
number of marine mammals potentially affected, which must be reported
to NMFS within 90 days after the survey;
To compare the distance and distribution of marine mammals
relative to the source vessel at times with and without seismic
activity; and
To obtain data on the behavior and movement patterns of
marine mammals observed and compare those at times with and without
seismic activity.
Marine Mammal Observer Protocol
BP intends to work with experienced PSOs that have had previous
experience working on seismic survey vessels, which will be especially
important for the lead PSO on the source vessels. At least one Alaska
Native resident, who is knowledgeable about Arctic marine mammals and
the subsistence hunt, is expected to be included as one of the team
members aboard the vessels. Before the start of the seismic survey the
crew of the seismic source vessels will be briefed on the function of
the PSOs, their monitoring protocol, and mitigation measures to be
implemented. They will also be aware of the monitoring objectives of
the dedicated monitoring vessel, and how their observations can affect
the operations.
On all source vessels, at least one observer will monitor for
marine mammals at any time during daylight hours (there will be no
periods of total darkness until mid-August). PSOs will be on duty in
shifts of a maximum of 4 hours at a time, although the exact shift
schedule will be established by the lead PSO in consultation with the
other PSOs.
The three source vessels will offer suitable platforms for PSOs.
Observations will be made from locations where PSOs have the best view
around the vessel. During daytime, the PSO(s) will scan the area around
the vessel systematically with reticle binoculars (e.g., 7x50 Fujinon)
and with the naked eye. Laser range-finding binoculars (Leica LRF 1200
laser rangefinder or equivalent) will be available to assist with
distance estimation, using other vessels in the area as targets. Laser
range finding binoculars are generally not useful in measuring
distances to animals directly.
Communication Procedures
When marine mammals in the water are detected within or about to
enter the designated safety zones, the airgun(s) power-down or shut-
down procedures will be implemented immediately. To assure prompt
implementation of power-downs and shut-downs, multiple channels of
communication between the PSOs and the airgun technicians will be
established. During the power-down and shut-down, the PSO(s) will
continue to maintain watch to determine when the animal(s) are outside
the safety radius. Airgun operations can be resumed with a ramp-up
procedure (depending on the extent of the power down) if the observers
have visually confirmed that the animal(s) moved outside the exclusion
zone, or if the animal(s) were not observed within the safety zone for
15 minutes (pinnipeds and small toothed whales) or for 30 minutes (for
baleen whales and large toothed whales). Direct communication with the
airgun operator will be maintained throughout these procedures.
Data Recording
All marine mammal observations and any airgun power-down, shut-down
and ramp-up will be recorded in a standardized format. Data will be
entered into a custom database using a notebook computer. The accuracy
of the data entry will be verified by computerized validity data checks
as the data are entered and by subsequent manual checking of the
database after each day. 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, or
other programs for further processing and archiving.
Visual Monitoring Outside the Barrier Islands
The main purpose of the PSOs on the monitoring vessel that will
operate outside the barrier islands is to monitor the 120 dB
disturbance zone during daylight hours for the presence of four or more
bowhead cow/calf pairs. The predicted distances to received levels of
120 dB are 6.4 km for the 640 in\3\ array and 5.7 km for the 320 in\3\
array. The distance to the 160 dB disturbance zone is small enough (1.8
km for the 640 in\3\ and 1.5 km for the 320 in\3\ array) to be covered
by the PSOs on the source vessels. Of the two PSOs on the monitoring
vessel, one will be on watch at all times during daylight hours to
monitor the disturbance zones and to communicate any sightings of four
bowhead cow/calf pairs to the PSOs on the source vessels. The shift
schedule and observer protocol will be similar to that of the PSOs on
the source vessels.
Channels of communication between the lead PSOs on the source
vessels and the dedicated monitoring vessel will also be established.
If four or more bowhead cow/calf pairs are observed within or entering
the 120 dB disturbance zone the lead PSO on monitoring vessel will
immediately contact the lead PSO on the source vessel, who will ensure
prompt implementation of airgun power downs or shutdowns. The lead PSO
of the monitoring vessel will continue monitoring the 120 dB zone and
notify the PSO on the source vessel when the cow/calf pairs have left
the safety zone or when they haven't been observed within the safety
zone for 30 minutes. Under these conditions ramp-up can be initiated.
These vessel based surveys outside the barrier islands will be
conducted up to 3 days per week, weather depending.
[[Page 40017]]
Anticipated start date is August 25, 2012, and these surveys will be
continuing until the end of the data acquisition period. During this
period data acquisition will take place only inside the barrier
islands. The vessel will follow transect lines within the 120 dB zone
that are designed in such a way that the area ensonified by 120 dB or
more will be covered. The exact start and end point will depend on the
area to be covered by the source vessels during that particular day.
Monitoring Plan Peer Review
The MMPA requires that monitoring plans be independently peer
reviewed ``where the proposed activity may affect the availability of a
species or stock for taking for subsistence uses'' (16 U.S.C.
1371(a)(5)(D)(ii)(III)). Regarding this requirement, NMFS' implementing
regulations state, ``Upon receipt of a complete monitoring plan, and at
its discretion, [NMFS] will either submit the plan to members of a peer
review panel for review or within 60 days of receipt of the proposed
monitoring plan, schedule a workshop to review the plan'' (50 CFR
216.108(d)).
NMFS convened an independent peer review panel to review BP's
mitigation and monitoring plan in its IHA application for taking marine
mammals incidental to the proposed OBC seismic survey in the Simpson
Lagoon of the Alaskan Beaufort Sea, during 2012. The panel met on
January 5 and 6, 2012, and provided their final report to NMFS on
February 29, 2012. The full panel report can be viewed at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.
The peer review panel report contains recommendations that the
panel members felt were applicable to BP's monitoring plans.
Specifically the panel commented on issues related to: (1) Vessel-based
marine mammal observers (MMOs), (2) MMO training, (3) Data recording,
(4) Data analysis, and (5) Acoustical monitoring.
NMFS has reviewed the report and evaluated all recommendations made
by the panel. NMFS has determined that there are several measures that
BP can incorporate into its 2012 OBC seismic survey. Additionally,
there are other recommendations that NMFS has determined would also
result in better data collection, and could potentially be implemented
by oil and gas industry applicants, but which likely could not be
implemented for the 2012 open water season due to technical issues (see
below). While it may not be possible to implement those changes this
year, NMFS believes that they are worthwhile and appropriate
suggestions that may require a bit more time to implement, and BP
should consider incorporating them into future monitoring plans should
BP decide to apply for IHAs in the future.
The following subsections lay out measures that NMFS is requiring
BP to implement as part of its 2012 OBC seismic survey and measures for
future implementation.
To Be Implemented for Inclusion in the 2012 Monitoring Plan
(1) Vessel-Based Marine Mammal Observers
Utilize crew members to assist the MMOs. Crew members
should not be used as primary MMOs because they have other duties and
generally do not have the same level of expertise, experience, or
training as MMOs, but they could be stationed on the fantail of the
vessel to observe the near field, especially the area around the airgun
array and implement a rampdown or shutdown if a marine mammal enters
the safety zone (or exclusion zone).
If crew members are to be used as MMOs, they should go
through some basic training consistent with the functions they will be
asked to perform. The best approach would be for crew members and MMOs
to go through the same training together.
As BP plans to have a marine mammal survey vessel outside
the barrier islands after 25 August, the panel recommends BP use MMOs
on the vessel to monitor for the presence and behavior of marine
mammals in the offshore area projected to be exposed to seismic sounds.
(2) MMO Training
BP could improve its MMO training by implementing panel
recommendations from previous years (on other seismic survey programs).
These recommendations include:
[cir] Observers should be trained using visual aids (e.g., videos,
photos), to help them identify the species that they are likely to
encounter in the conditions under which the animals will likely be
seen.
[cir] Observer teams should include Alaska Natives, and all
observers should be trained together. Whenever possible, new observers
should be paired with experienced observers to avoid situations where
lack of experience impairs the quality of observations.
[cir] Observers should understand the importance of classifying
marine mammals as ``unknown'' or ``unidentified'' if they cannot
identify the animals to species with confidence. In those cases, they
should note any information that might aid in the identification of the
marine mammal sighted. For example, for an unidentified mysticete
whale, the observers should record whether the animal had a dorsal fin.
[cir] Observers should use the best possible positions for
observing (e.g., outside and as high on the vessel as possible), taking
into account weather and other working conditions.
BP should train its MMOs to follow a scanning schedule
that consistently distributes scanning effort according to the purpose
and need for observations. For example, the schedule might call for 60
percent of scanning effort to be directed toward the near field and 40
percent at the far field. All MMOs should follow the same schedule to
ensure consistency in their scanning efforts.
MMOs also need training in documenting the behaviors of
marine mammals. MMOs should simply record the primary behavioral state
(i.e., traveling, socializing, feeding, resting, approaching or moving
away from vessels) and relative location of the observed marine
mammals.
(3) Data Recording
MMOs should record observations of marine mammals hauled
out on barrier islands. Because of the location of BP's proposed
survey, most (if not all) of the marine mammals observed in the lagoon
will be pinnipeds. It is feasible that the surveys may alter the
hauling out patterns of pinnipeds, so observations of them should be
recorded.
BP should work with its observers to develop a means for
recording data that does not reduce observation time significantly.
Possible options include the use of a voice recorder during
observations followed by later transcriptions, or well- designed
software programs that minimize the time required to enter data. Other
techniques also may be suitable.
(4) Data Analysis and Presentation of Data in Reports
Estimation of potential takes or exposures should be
improved for times with low visibility (such as during fog or darkness)
through interpolation or possibly using a probability approach. For
instance, for periods of fog or darkness one could use marine mammal
observations obtained during a specified period of time before or after
the time when visibility was restricted. Those data could be used to
interpolate possible takes during periods of restricted visibility.
[[Page 40018]]
Simpson Lagoon is relatively shallow, and marine mammal
distribution likely will be closely linked to water depth. To account
for this confounding factor, depth should be continuously recorded by
the vessel and for each marine mammal sighting. Water depth should be
accounted for in the analysis of take estimates.
BP should be very clear in their report about what periods
are considered ``non-seismic'' for analyses.
BP should examine data from BWASP and other such programs
to assess possible impacts from their seismic survey.
The panel states that it believes the best ways to present
data and results are described in peer-review reports from previous
years. These recommendations include:
[cir] To better assess impacts to marine mammals, data analysis
should be separated into periods when a seismic airgun array (or a
single mitigation airgun) is operating and when it is not. Final and
comprehensive reports to NMFS should summarize and plot:
[ssquf] Data for periods when a seismic array is active and when it
is not; and
[ssquf] The respective predicted received sound conditions over
fairly large areas (tens of km) around operations.
[cir] To help evaluate the effectiveness of MMOs and more
effectively estimate take, reports should include sightability curves
(detection functions) for distance-based analyses.
[cir] To better understand the potential effects of oil and gas
activities on marine mammals and to facilitate integration among
companies and other researchers, the following data should be obtained
and provided electronically in the 90- day report:
[ssquf] The location and time of each aerial or vessel-based
sighting or acoustic detection;
[ssquf] Position of the sighting or acoustic detection relative to
ongoing operations (i.e., distance from sightings to seismic operation,
drilling ship, support ship, etc.), if known;
[ssquf] The nature of activities at the time (e.g., seismic on/
off);
[ssquf] Any identifiable marine mammal behavioral response
(sighting data should be collected in a manner that will not detract
from the MMO's ability to detect marine mammals); and
[ssquf] Adjustments made to operating procedures.
BP should improve take estimates and statistical inference
into effects of the activities by incorporating the following measures:
[ssquf] Reported results from all hypothesis tests should include
estimates of the associated statistical power.
[ssquf] Estimate and report uncertainty in all take estimates.
Uncertainty could be expressed by the presentation of confidence
limits, a minimum-maximum, posterior probability distribution, etc.;
the exact approach would be selected based on the sampling method and
data available.
(5) Acoustical Monitoring
BP should also use the offshore vessel to monitor
(periodically) the propagation of airgun sounds from within the lagoon
into offshore areas during its marine mammal survey using a dipping
hydrophone.
To help verify the propagation model results, the panel
also recommends additional acoustic monitoring with bottom mounted
recorders. Recorders should be deployed throughout the seismic survey.
One suggestion is to deploy instruments including: One at the cut, or
break, between Leavitt and Spy islands at about the 5 m isobath; one
north of the center of Leavitt Island at the 10 m isobath; and one off
the east end of Pingok Island at the 10 m isobath.
Recommendations To Be Considered for Future Monitoring Plans
In addition, the panelists recommended that (1) BP continue to
develop and test observational aids to assist with visibility during
night, poor light conditions, inclement weather, etc.; and (2) BP
conduct additional acoustic monitoring with bottom mounted recorders to
monitor for calling marine mammals. It may be possible to evaluate
calling rates relative to seismic operations or received levels of
seismic sounds. Additionally, Shell will have several acoustic arrays
in the general area. Those arrays will provide a basis for determining
locations of calling marine mammals. NMFS should encourage BP to
request data from Shell to help examine impacts of the seismic survey
on the distribution of calling bowheads and other marine mammals.
After discussion with BP, NMFS decided not to implement these two
recommendations for BP's 2012 OBC seismic survey because most of BP's
survey would occur during the time when there will be very short low-
light hours. As for the second recommendation, NMFS realized that given
the complexity in marine mammal passive acoustic localization, BP will
not have the time to implement this recommendation for its 2012 survey.
(2) Reporting Measures
Sound Source Verification Reports
A report on the preliminary results of the sound source
verification measurements, including the measured 190, 180, 160, and
120 dB (rms) radii of the airgun sources, shall be submitted within 14
days after collection of those measurements at the start of the field
season. This report will specify the distances of the exclusion zones
that were adopted for the survey.
Technical Reports
The results of BP's 2012 vessel-based monitoring, including
estimates of ``take'' by harassment, shall be presented in the ``90-
day'' and Final Technical reports. The Technical Reports should be
submitted to NMFS within 90 days after the end of the seismic survey.
The Technical Reports will include:
(a) Summaries of monitoring effort (e.g., total hours, total
distances, and marine mammal distribution through the study period,
accounting for sea state and other factors affecting visibility and
detectability of marine mammals);
(b) Analyses of the effects of various factors influencing
detectability of marine mammals (e.g., sea state, number of observers,
and fog/glare);
(c) Species composition, occurrence, and distribution of marine
mammal sightings, including date, water depth, numbers, age/size/gender
categories (if determinable), group sizes, and ice cover;
(d) To better assess impacts to marine mammals, data analysis
should be separated into periods when a seismic airgun array (or a
single mitigation airgun) is operating and when it is not. Final and
comprehensive reports to NMFS should summarize and plot:
Data for periods when a seismic array is active and when
it is not; and
The respective predicted received sound conditions over
fairly large areas (tens of km) around operations;
(e) Sighting rates of marine mammals during periods with and
without airgun activities (and other variables that could affect
detectability), such as:
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;
Distribution around the survey vessel versus airgun
activity state; and
Estimates of take by harassment;
(f) Reported results from all hypothesis tests should include
[[Page 40019]]
estimates of the associated statistical power when practicable;
(g) Estimate and report uncertainty in all take estimates.
Uncertainty could be expressed by the presentation of confidence
limits, a minimum-maximum, posterior probability distribution, etc.;
the exact approach would be selected based on the sampling method and
data available;
(h) The report should clearly compare authorized takes to the level
of actual estimated takes; and
Notification of Injured or Dead Marine Mammals
In the unanticipated event that survey operations clearly cause the
take of a marine mammal in a manner prohibited by this Authorization,
such as an injury (Level A harassment), serious injury or mortality
(e.g., ship-strike, gear interaction, and/or entanglement), BP shall
immediately cease survey operations and immediately report the incident
to NMFS and the Alaska Regional Stranding coordinators. The report must
include the following information: (1) Time, date, and location
(latitude/longitude) of the incident; (2) the name and type of vessel
involved; (3) the vessel's speed during and leading up to the incident;
(4) description of the incident; (5) status of all sound source use in
the 24 hours preceding the incident; (6) water depth; (7) environmental
conditions (e.g., wind speed and direction, Beaufort sea state, cloud
cover, and visibility); (8) description of marine mammal observations
in the 24 hours preceding the incident; (9) species identification or
description of the animal(s) involved; (10) the fate of the animal(s);
and (11) photographs or video footage of the animal (if equipment is
available).
Activities shall not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS shall work with BP to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. BP may not resume their
activities until notified by NMFS via letter, email, or telephone.
In the event that BP 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), BP
shall immediately report the incident to NMFS and the NMFS Alaska
Stranding Hotline and/or by email to the Alaska Regional Stranding
Coordinators, within 24 hours of the discovery. The report must include
the same information identified above. Activities may continue while
NMFS reviews the circumstances of the incident. NMFS will work with BP
to determine whether modifications in the activities are appropriate.
In the event that BP 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 IHA (e.g., previously
wounded animal, carcass with moderate to advanced decomposition, or
scavenger damage), BP shall report the incident to NMFS and the NMFS
Alaska Stranding Hotline and/or by email to the Alaska Regional
Stranding Coordinators, within 24 hours of the discovery. BP shall
provide photographs or video footage (if available) or other
documentation of the stranded animal sighting to NMFS and the Marine
Mammal Stranding Network. BP can continue its operations under such a
case.
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]. Only take by Level B behavioral
harassment is anticipated as a result of the proposed open-water marine
survey program. Anticipated impacts to marine mammals are associated
with noise propagation from the survey airgun(s) used in the OBC
seismic survey.
The full suite of potential impacts to marine mammals was described
in detail in the ``Potential Effects of the Specified Activity on
Marine Mammals'' section found in the Notice of Proposed IHA (77 FR
28530; May 1, 2012). The potential effects of sound from the open-water
seismic survey might include one or more of the following: Tolerance;
masking of natural sounds; behavioral disturbance; non-auditory
physical effects; and, at least in theory, temporary or permanent
hearing impairment (Richardson et al. 1995). As discussed earlier in
this document, the most common impact will likely be from behavioral
disturbance, including avoidance of the ensonified area or changes in
speed, direction, and/or diving profile of the animal. For reasons
discussed previously in this document, hearing impairment (TTS and PTS)
is highly unlikely to occur based on the required mitigation and
monitoring measures that would preclude marine mammals being exposed to
noise levels high enough to cause hearing impairment.
For impulse sounds, such as those produced by airgun(s) used in the
shallow hazards survey, NMFS uses the 160 dBrms re 1 [mu]Pa
isopleth to indicate the onset of Level
B harassment. BP provided calculations for the 160- and 120-dB
isopleths produced by these activities and then used those isopleths to
estimate takes by harassment. NMFS used the calculations to make the
necessary MMPA findings. BP provided a full description of the
methodology used to estimate takes by harassment in its IHA application
(see ADDRESSES), which was also provided in the Notice of Proposed IHA
(77 FR 28530; May 1, 2012). A summary of that information is provided
here, as it has not changed from the proposed notice.
BP has requested an authorization to take 11 marine mammal species
by Level B harassment. These 11 marine mammal species are: beluga whale
(Delphinapterus leucas), killer whale (Orcinus orca), harbor porpoise
(Phocoena phocoena), bowhead whale (Balaena mysticetus), gray whale
(Eschrichtius robustus), humpback whale (Megaptera novaeangliae), minke
whale (Balaenoptera acutorostrata), bearded seal (Erignathus barbatus),
ringed seal (Phoca hispida), spotted seal (P. largha), and ribbon seal
(Histriophoca fasciata). However, due to the extralimital distribution
of humpback whales, NMFS considers that the occurrence of this species
in the vicinity of BP's seismic survey area is unlikely.
Basis for Estimating ``Take by Harassment''
As stated previously, it is current NMFS policy to estimate take by
Level B harassment for impulse sounds at a received level of 160
dBrms re 1[mu]Pa. However, not all animals react to sounds
at this low level, and many will not show strong reactions (and in some
cases any reaction) until sounds are much stronger. 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)). Tables 7, 9, and 11 in Southall et al. (2007) outline the
numbers of low-frequency cetaceans, mid-frequency cetaceans, and
pinnipeds in water, respectively, reported as
[[Page 40020]]
having behavioral responses to multi-pulses in 10-dB received level
increments. These tables illustrate that for the studies summarized the
more severe reactions did not occur until sounds were much higher than
160 dBrms re 1[mu]Pa.
As described earlier in the document, two main source vessels and a
mini source vessel would be used to conduct the OBC seismic surveys in
the Simpson Lagoon. Each of the main source vessels would be equipped
with two subarrays containing eight 40 in\3\ airguns, with a total
volume displacement of 640 in\3\. The mini source vessel would be
equipped with one subarray containing eight 40 in\3\ airguns, with a
total displacement volume of 320 in\3\. Modeling results show that the
160 dB isopleths for the 640 in\3\, 320 in\3\, and 40 in\3\ airgun
arrays inside the barrier islands are approximately 1,800 m, 1,500 m,
and 700 m from the source, respectively; the 160 dB isopleths for the
640 in\3\ and 40 in\3\ airgun arrays outside the barrier islands are
approximately 5,500 m and 810 m fromthe source, respectively (Please
see above for detailed description of the exclusion and disturbance
zones).
The radii associated with received sound levels of 160 dB re 1
[mu]Pa (rms) or higher are used to calculate the number of potential
marine mammal ``exposures'' to airgun sounds. The potential number of
each species that might be exposed to received pulsed sound levels of
>=160 dB re 1 [mu]Pa (rms) is calculated by multiplying the expected
species density with the anticipated area to be ensonified to that
level during airgun operations. Bowhead and beluga whales are migrating
through the area, so every encounter likely involves a new individual.
Although seal species are also known to cover large distances, they are
expected to linger longer within a certain area, and so one individual
might be exposed multiple times.
The area expected to be ensonified was determined by entering the
seismic survey lines into a MapInfo Geographic Information System
(GIS). GIS was then used to identify the relevant areas by ``drawing''
the applicable 160-dB buffer of the 640-in\3\ array around each seismic
source line and calculating the total area within the buffers. This was
done for the survey area outside the barrier islands and inside the
barrier islands separately. The area ensonified with pulsed sound
levels of >=160 dB re 1 [mu]Pa (rms) from airgun operations outside the
barrier islands is estimated as 197.5 mi\2\ (512 km\2\) and from airgun
operations inside the barrier islands 105 mi\2\ (272 km\2\).
Summer density (see below) estimates of marine mammals will be
applied to all (100%) survey effort outside the barrier islands and to
60% survey effort inside the barrier islands. Fall densities are not
applied to the outside barrier islands survey effort, since no survey
effort is planned after August 25. Fall densities are applied to 100%
survey effort inside the barrier islands activity, because some of the
source lines will be rerun in order to image the full fold area
adequately.
Marine Mammal Density Estimates
Because most cetacean species show a distinct seasonal
distribution, density estimates for the central Beaufort Sea have been
derived for the summer period (covering July and August) and the fall
period (covering September and October). Animal densities encountered
in the Beaufort Sea during both of these time periods will further
depend on the presence of ice. However, if ice cover within or close to
the seismic survey area is more than approximately 10%, seismic survey
activities may not start or be halted. Cetacean and pinniped densities
related to ice conditions are therefore not included in BP's IHA
application. Pinniped species in the Beaufort Sea do not show a
distinct seasonal distribution during the period July-early-October and
as such density estimates derived for seal species are used for both
the summer and fall periods.
In addition to seasonal variation in densities, spatial
differentiation is an important factor for marine mammal densities,
both in latitudinal and longitudinal gradient. Taking into account the
size and location of the proposed seismic survey area and the
associated area of influence, only the nearshore zone (defined as the
area between the shoreline and the 50 m [164 ft] bathymetry line) of
the Beaufort Sea was considered to be relevant for the calculation of
densities.
Density estimates are based on best available scientific data. In
cases where the best available data were collected in regions,
habitats, or seasons that differ from the proposed survey activities,
information from monitoring results collected in similar habitats,
regions or seasons was used. Some sources from which densities were
used include correction factors to account for perception and
availability bias in the reported densities. Perception bias is
associated with diminishing probability of sighting with increasing
lateral distance from the trackline, where an animal is present at the
surface but could be missed. Availability bias refers to the fact that
the animal might be present but is not available at the surface. The
uncorrected number of marine mammals observed is therefore always lower
than the actual numbers present. Unfortunately, for most marine mammals
not enough information is available to calculate these two correction
factors. The density estimates provided in the BP's IHA request are
therefore based on uncorrected data, unless mentioned otherwise.
Because the available density data is not always representative for
the area of interest, and correction factors were not always known,
there is some uncertainty in the data and assumptions used in the
density calculations. To provide allowance for these uncertainties,
maximum density estimates have been provided in addition to average
density estimates. The marine mammal densities presented are believed
to be close to, and in most cases higher than, the densities that are
expected to be encountered during the proposed survey.
Detailed density information of marine mammal species present in
the vicinity of BP's OBC seismic area is described in detail in the
Federal Register notice for the proposed IHA (77 FR 28530; May 1,
2012). Table 3 is the summary of the marine mammal density used to
calculate estimated takes.
Table 3--Expected Densities of Marine Mammals in the Simpson Lagoon
Survey Area
------------------------------------------------------------------------
Summer Autumn
densities densities
Species (/ (/
km\2\) km\2\)
------------------------------------------------------------------------
Bowhead whale................................. 0.0065 0.1226
Beluga whale.................................. 0.0008 0.0136
Ringed seal................................... 0.1680 0.1680
Bearded seal.................................. 0.0124 0.0124
Spotted seal.................................. 0.0020 0.0020
------------------------------------------------------------------------
Potential Number of Takes by Harassment
Numbers of marine mammals that might be present and potentially
taken are summarized in Table 4 based on available data about mammal
distribution and densities at different locations and times of the year
as described above.
Some of the animals estimated to be exposed, particularly migrating
bowhead whales, might show avoidance reactions before being exposed to
>=160 dB re 1 [mu]Pa (rms). Thus, these calculations actually estimate
the number of individuals potentially exposed to >=160 dB (rms) that
would
[[Page 40021]]
occur if there were no avoidance of the area ensonified to that level.
For beluga whales and spotted seals that may form groups,
additional takes were requested on top of the density-based take
calculation in the event a large group is encountered during the
survey. For marine mammal species that are extralimital and for which
no density estimates are available in the vicinity of the proposed
project area (such as gray, minke, and killer whales, harbor porpoise,
and ribbon seal), a small number of takes have been requested in case
they are encountered (Table 4).
Table 4--Estimates of the Possible Numbers of Marine Mammals Taken by Level B Harassment (Exposed to >=160 dB re
1 [mu]Pa (rms)) During BP's Proposed Seismic Program in the Beaufort Seas, July-October 2012
----------------------------------------------------------------------------------------------------------------
Outside barrier Inside barrier islands
islands ------------------------------------ Total estimated
Species ------------------ takes
Summer Summer Autumn
----------------------------------------------------------------------------------------------------------------
Bowhead whale........................... 3 1 33 37
Beluga whale............................ 0 0 4 50 *
Gray whale.............................. ................ ................ ................ 3
Minke whale............................. ................ ................ ................ 2
Killer whale............................ ................ ................ ................ 3
Harbor porpoise......................... ................ ................ ................ 3
Ringed seal............................. 60 19 32 111
Bearded seal............................ 9 3 5 17
Spotted seal............................ 1 0 1 20 *
Ribbon seal............................. ................ ................ ................ 3
----------------------------------------------------------------------------------------------------------------
* Additional takes were requested in the event that a large group of beluga whales and spotted seals is
encountered.
Estimated Take Conclusions
Cetaceans--Effects on cetaceans are generally expected to be
restricted to avoidance of an area around the seismic survey and short-
term changes in behavior, falling within the MMPA definition of ``Level
B harassment''.
Using the 160 dB criterion, the average estimates of the numbers of
individual cetaceans exposed to sounds = 160 dB (rms) re 1
[mu]Pa represent varying proportions of the populations of each species
in the Beaufort Sea and adjacent waters. For species listed as
``Endangered'' under the ESA, the estimates include approximately 37
bowheads. This number is approximately 0.24% of the Bering-Chukchi-
Beaufort population of over 15,232 assuming 3.4% annual population
growth from the estimate of over 10,545 animals in 2001 (Zeh and Punt
2005). For other cetaceans that might occur in the vicinity of the
Simpson Lagoon survey area, they also represent a very small proportion
of their respective populations. The average estimates of the number of
belugas (with additional takes to account for a chance encounter of a
large group) that might be exposed to 160 dB re 1 [mu]Pa is 50, which
represents 0.13% of the Beaufort Sea population (or 1.35% of the
Eastern Chukchi Sea population, or a mix between these two populations)
of the beluga whales. In addition, the average estimates of gray,
minke, and killer whales, and harbor porpoise that might be exposed to
=160 dB re 1 [mu]Pa are 3, 2, 3, and 3. These numbers
represent 0.02%, 0.20%, 0.96%, and 0.0062% of these species of their
respective populations in the proposed action area.
Although humpback whales are not likely to be encountered in BP's
proposed seismic survey area, NMFS has analyzed the possibility of an
occasional exposure of up to 2 humpback whales to received noise levels
by Level B behavioral harassment. This would represent 0.21% of the
Western North Pacific stock of approximately 938 humpback whales in the
proposed action area. Based on the analysis, NMFS has determined that
such level of take will have negligible impacts to the humpback whales.
Since analysis conducted by NMFS' Alaska Regional Office (AKRO) on
section 7 consultation on ESA-listed species showed that humpback
whales would not be affected, no humpback whale take is authorized by
AKRO, therefore, the final IHA does not include takes of humpback whale
as well.
Seals--A few seal species are likely to be encountered in the study
area, but ringed seal is by far the most abundant in this area. The
average estimates of the numbers of individuals exposed to sounds at
received levels =160 dB (rms) re 1 [mu]Pa during the
proposed shallow hazards survey are as follows: ringed seals (111),
bearded seals (17), spotted seals (20, with additional takes to count
for chance encounter of a group), and ribbon seals (2). These numbers
represent 0.05%, 0.01%, 0.03%, and 0.0033% of Alaska stocks of ringed,
bearded, spotted, and ribbon seals, respectively.
Negligible Impact and Small Numbers Analysis and Determination
NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``* * *
an impact resulting from the specified activity that cannot be
reasonably expected to, and is not reasonably likely to, adversely
affect the species or stock through effects on annual rates of
recruitment or survival.'' In making a negligible impact determination,
NMFS considers a variety of factors, including but not limited to: (1)
The number of anticipated mortalities; (2) the number and nature of
anticipated injuries; (3) the number, nature, intensity, and duration
of Level B harassment; and (4) the context in which the takes occur.
No injuries or mortalities are anticipated to occur as a result of
BP's 2012 OBC seismic survey in the Simpson Lagoon of the Alaskan
Beaufort Sea, and none are authorized. In addition, these surveys will
use relatively small 640 in\3\ airgun arrays, which have much less
acoustic power outputs compared to conventional airgun arrays with
displacement volume in the range of thousands cubic inches.
Additionally, the survey areas are in shallow waters, with
approximately 42% of the survey area located inside the barrier islands
(depth: 0-9 ft, or 0-3 m) and 33% located outside the barrier islands
(depth: 3-45 ft, or 1-15 m), where horizontal sound propagation of low
frequency airgun pulses is severely limited. For the seismic survey
inside the barrier islands, the islands provide a natural barrier that
would effectively reduce sound propagation out to the open ocean, if
not completely
[[Page 40022]]
eliminate its propagation. The modeled isopleths at 160 dB within the
barrier islands is expected to be approximately 1.8 km, and 5.5 km
outside barrier islands, from an airgun array of 640 in\3\ (see
discussion earlier). Additionally, animals in the area are not expected
to incur hearing impairment (i.e., TTS or PTS) or non-auditory
physiological effects. Takes will be limited to Level B behavioral
harassment. Although it is possible that some individuals of marine
mammals may be exposed to sounds from the proposed seismic survey
activities more than once, the expanse of these multi-exposures are
expected to be less extensive since both the animals and the survey
vessels will be moving constantly in and out of the survey areas.
Most of the bowhead whales encountered during the summer will
likely show overt disturbance (avoidance) only if they receive airgun
sounds with levels >= 160 dB re 1 [mu]Pa. Odontocete reactions to
seismic energy pulses are usually assumed to be limited to shorter
distances from the airgun(s) than are those of mysticetes, probably in
part because odontocete low-frequency hearing is assumed to be less
sensitive than that of mysticetes. However, at least when in the
Canadian Beaufort Sea in summer, belugas appear to be fairly responsive
to seismic energy, with few being sighted within 6-12 mi (10-20 km) of
seismic vessels during aerial surveys (Miller et al. 2005). Belugas
will likely occur in small numbers in the Beaufort Sea during the
survey period and few will likely be affected by the survey activity.
In addition, due to the constant moving of the survey vessel, the
duration of the noise exposure by cetaceans to seismic impulse would be
brief. For the same reason, it is unlikely that any individual animal
would be exposed to high received levels multiple times.
Taking into account the mitigation measures that are planned,
effects on cetaceans are generally expected to be restricted to
avoidance of a limited area around the survey operation and short-term
changes in behavior, falling within the MMPA definition of ``Level B
harassment''. The many reported cases of apparent tolerance by
cetaceans of seismic exploration, vessel traffic, and some other human
activities show that co-existence is possible. Mitigation measures such
as controlled vessel speed, dedicated marine mammal observers, non-
pursuit, and shut downs or power downs when marine mammals are seen
within defined ranges will further reduce short-term reactions and
minimize any effects on hearing sensitivity. In all cases, the effects
are expected to be short-term, with no lasting biological consequence.
Of the eleven marine mammal species with possible occurrence in the
proposed marine survey area, only the bowhead and humpback whales are
listed as endangered under the ESA. These species are also designated
as ``depleted'' under the MMPA. Despite these designations, the Bering-
Chukchi-Beaufort stock of bowheads has been increasing at a rate of 3.4
percent annually for nearly a decade (Allen and Angliss 2010).
Additionally, during the 2001 census, 121 calves were counted, which
was the highest yet recorded. The calf count provides corroborating
evidence for a healthy and increasing population (Allen and Angliss
2010). The occurrence of humpback whales in the proposed marine survey
areas is considered extralimital, and therefore no takes are included
in the IHA. There is no critical habitat designated in the U.S. Arctic
for the bowhead and humpback whale. The Alaska stock of bearded seals,
part of the Beringia distinct population segment (DPS), and the Arctic
stock of ringed seals, have been proposed by NMFS for listing as
threatened under the ESA (bearded seals: 75 FR 77496; December 10,
2011; ringed seal: 75 FR 77476; December 10, 2011). None of the other
species that may occur in the project area are listed as threatened or
endangered under the ESA or designated as depleted under the MMPA.
Potential impacts to marine mammal habitat were discussed
previously in this document (see the ``Anticipated Effects on Habitat''
section). Although some disturbance is possible to food sources of
marine mammals, the impacts are anticipated to be minor enough as to
not affect rates of recruitment or survival of marine mammals in the
area. Based on the vast size of the Arctic Ocean where feeding by
marine mammals occurs versus the localized area of the marine survey
activities, any missed feeding opportunities in the direct project area
would be minor based on the fact that other feeding areas exist
elsewhere.
The authorized takes represent 0.13% of the Beaufort Sea population
of approximately 39,258 beluga whales (or 1.35% of the Eastern Chukchi
Sea population of approximately 3,710 beluga whales, or a mix of each
population; Allen and Angliss 2010), 1.59% of Aleutian Island and
Bering Sea stock of approximately 314 killer whales, 0.004% of Bering
Sea stock of approximately 48,215 harbor porpoises, 0.02% of the
Eastern North Pacific stock of approximately 19,126 gray whales, 0.24%
of the Bering-Chukchi-Beaufort population of 15,232 bowhead whales
assuming 3.4 percent annual population growth from the estimate of
10,545 animals (Zeh and Punt, 2005), and 0.20% of the Alaska stock of
approximately 1,003 minke whales. The take estimates presented for
bearded, ringed, spotted, and ribbon seals represent 0.01, 0.05, 0.03,
and 0.0033% of U.S. Arctic stocks of each species, respectively. These
take numbers represent the percentage of each species or stock that
could be taken by Level B behavioral harassment if each animal is taken
only once. In addition, the mitigation and monitoring measures
(described previously in this document) that are included in the IHA
(if issued) are expected to reduce even further any potential
disturbance to marine mammals.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the mitigation and monitoring
measures, NMFS finds that BP's proposed 2012 OBC seismic survey in the
Simpson Lagoon of the Alaskan Beaufort Sea may result in the incidental
take of small numbers of marine mammals, by Level B harassment only,
and that the total taking from the marine surveys will have a
negligible impact on the affected species or stocks.
Unmitigable Adverse Impact Analysis and Determination
NMFS has determined that BP's proposed 2012 OBC seismic survey in
the Beaufort Sea will not have an unmitigable adverse impact on the
availability of species or stocks for taking for subsistence uses. This
determination is supported by information contained in this document
and BP's CAA and draft POC. BP has adopted a spatial and temporal
strategy for its Simpson Lagoon operations that should minimize impacts
to subsistence hunters. Specifically, BP's Simpson Lagoon OBC seismic
survey would occur during the July to October open water season, would
not start its airgun operations within the barrier islands before July
25, and will terminate its operations outside the barrier islands after
August 25 before the fall bowhead whale hunt. Due to the timing of the
project and the distance from the surrounding communities
(approximately 35 miles northeast from Nuiqsut, 35 miles west from
Cross Island, 150 miles west from Kaktovik and 180 miles east from
Barrow), it is anticipated to have no effects on spring harvesting and
little or no effects on the occasional summer harvest of beluga
[[Page 40023]]
whale, subsistence seal hunts (ringed and spotted seals are primarily
harvested in winter while bearded seals are hunted during July-
September in the Beaufort Sea), or the fall bowhead hunt.
In addition, based on the measures described in BP's POC and CAA,
the proposed mitigation and monitoring measures (described earlier in
this document), and the project design itself, NMFS has determined that
there will not be an unmitigable adverse impact on subsistence uses
from BP's OBC seismic survey in the Simpson Lagoon of the Beaufort Sea.
Endangered Species Act (ESA)
There are two marine mammal species listed as endangered under the
ESA with confirmed or possible occurrence in the project area: The
bowhead and humpback whales. In addition, there are two marine mammal
species that are currently being proposed for listing under the ESA
with confirmed occurrence in the proposed project area: Ringed and
bearded seals. NMFS' Permits and Conservation Division consulted with
NMFS' Alaska Regional Office Division of Protected Resources under
section 7 of the ESA on the issuance of an IHA to BP under section
101(a)(5)(D) of the MMPA for this activity. A Biological Opinion was
issued on June 21, 2012, which concludes that issuance of the IHA is
not likely to jeopardize the continued existence of the ESA-listed
marine mammal species and species proposed for ESA-listing. In
addition, analysis by NMFS AKRO showed that humpback whale will not be
affected, therefore, no take was authorized. NMFS will issue an
Incidental Take Statement under this Biological Opinion which contains
reasonable and prudent measures with implementing terms and conditions
to minimize the effects of take of listed species.
National Environmental Policy Act (NEPA)
NMFS prepared an EA that includes an analysis of potential
environmental effects associated with NMFS' issuance of an IHA to BP to
take marine mammals incidental to conducting its OBC seismic survey in
the Simpson Lagoon area of the Beaufort Sea during the 2012 open water
season. NMFS has finalized the EA and prepared a FONSI for this action.
Therefore, preparation of an EIS is not necessary.
Authorization
As a result of these determinations, NMFS has issued an IHA to BP
to take marine mammals incidental to its 2012 OBC open-water seismic
survey in the Simpson Lagoon area of the Beaufort Sea, Alaska, provided
the previously mentioned mitigation, monitoring, and reporting
requirements are incorporated.
Dated: June 29, 2012.
Helen M. Golde,
Acting Director, Office of Protected Resources, National Marine
Fisheries Service.
[FR Doc. 2012-16584 Filed 7-5-12; 8:45 am]
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