Small Takes of Marine Mammals Incidental to Specified Activities; Seismic Survey in the Beaufort Sea, Alaska, Summer and Early Fall 2008, 45969-45994 [E8-18104]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 73, Number 153 (Thursday, August 7, 2008)]
[Notices]
[Pages 45969-45994]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-18104]


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

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XJ56


Small Takes of Marine Mammals Incidental to Specified Activities; 
Seismic Survey in the Beaufort Sea, Alaska, Summer and Early Fall 2008

AGENCY:  National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION:  Notice; issuance of an incidental take authorization.

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

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 PGS Onshore, Inc. (PGS) to 
take, by harassment, small numbers of six species of marine mammals 
incidental to an exploratory three-dimensional (3D) marine seismic 
survey in the Beaufort Sea, Alaska, utilizing an ocean bottom cable/
transition zone (OBC/TZ) technique in summer and early fall 2008.

DATES: Effective July 30, 2008, through July 29, 2009.

ADDRESSES: The application containing a list of references used in this 
document, an addendum to the application, and the IHA are available by 
writing to P. Michael Payne, Chief, Permits, Conservation and Education 
Division, Office of Protected Resources, National Marine Fisheries 
Service, 1315 East-West Highway, Silver Spring, MD 20910-3225 or by 
telephoning the contact listed below (FOR FURTHER INFORMATION CONTACT) 
or online at: https://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.
    A copy of the 2006 Minerals Management Service's (MMS) Final 
Programmatic Environmental Assessment (PEA) and/or the NMFS/MMS Draft 
Programmatic Environmental Impact Statement (DPEIS) are available on 
the internet at: https://www.mms.gov/alaska/. NMFS' 2008 Supplemental 
Environmental Assessment (SEA) is available at: https://
www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.

FOR FURTHER INFORMATION CONTACT: Candace Nachman, Office of Protected 
Resources, NMFS, (301) 713-2289 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 to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103 
as ''...an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the United States 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 the authorization.

Summary of Request

    On May 9, 2008, NMFS received an application from PGS for the 
taking, by Level B harassment only, of small

[[Page 45970]]

numbers of several species of marine mammals incidental to conducting 
an exploratory 3D marine seismic survey in the Alaskan Beaufort Sea, 
utilizing an OBC/TZ technique. PGS has been contracted by ENI Petroleum 
(ENI) to conduct the seismic survey. The proposed survey is scheduled 
to occur for a period of approximately 75 days from mid-July to late-
September, 2008, barring weather delays. The proposed survey location 
is in the Nikaitchuq Lease Block (see Figure 1 of PGS' application), 
north of Oliktok Point and covering Thetis, Spy, and Leavitt Islands, 
and would extend to the 5-km (3-mi) state/Federal water boundary line 
and would not go into Federal waters. The water depth in this area 
ranges from 0-15 m (0-49 ft), and a third of the project waters are 
shallower than 3 m (10 ft). The total area covered by source or 
receiver lines is 304.6 km\2\ (117.6 mi\2\); since the islands comprise 
approximately 1.7 km\2\ (0.7 mi\2\) of this, the total marine area is 
303 km\2\ (117 mi\2\).
    The work would be divided into two parts. Data acquisition (use of 
airguns) outside the barrier islands (Thetis, Spy, and Leavitt Islands) 
would be performed first and would be completed by August 25. This 
portion of the work would begin in the east and move toward the west. 
Data acquisition inside the barrier islands would then be conducted and 
would be completed by late-September. This portion of the work would 
also move from east to west. If additional data acquisition is required 
outside of the barrier islands after August 25, it would not recommence 
until the close of the fall bowhead hunt by the Nuiqsut community.

Description of Activity

    The OBC/TZ survey involves deploying cables from small boats, 
called DIB boats, to the ocean bottom, forming a pattern consisting of 
three parallel receiver line cables, each a maximum of 17.3 km (10.7 
mi) long and spaced approximately 200 m (656 ft) apart. Hydrophones and 
geophones attached to the cables are used to detect seismic energy 
reflected back from rock strata below the ocean bottom. The energy is 
generated from a submerged acoustic source, called a seismic airgun 
array, that releases compressed air into the water, creating an 
acoustic energy pulse directed downward toward the seabed. A detailed 
overview of the activities of this survey were provided in the Notice 
of Proposed IHA (73 FR 34254, June 17, 2008). No changes have been made 
to these proposed activities. Additional information is contained in 
PGS' application and application addendum, which are available for 
review (see ADDRESSES).

Comments and Responses

    A notice of receipt of PGS' MMPA application and NMFS' proposal to 
issue an IHA to PGS was published in the Federal Register on June 17, 
2008 (73 FR 34254). That notice described, in detail, PGS' proposed 
activity, the marine mammal species that may be affected by the 
activity, and the anticipated effects on marine mammals. During the 30-
day public comment period on PGS' application, comments were received 
from the Marine Mammal Commission (Commission), the Center for 
Biological Diversity (CBD) and Pacific Environment (collectively 
``CBD''), the Alaska Eskimo Whaling Commission (AEWC), the North Slope 
Borough (NSB) Office of the Mayor and the NSB Department of Wildlife 
Management (DWM), and Resisting Environmental Destruction on Indigenous 
Lands (REDOIL) and the Native Village of Point Hope (NVPH; collectively 
``REDOIL''). CBD attached the comments submitted by the Natural 
Resources Defense Council (NRDC) on the 2006 MMS PEA as an appendix to 
its comments on the IHA. With the exception of some comments relevant 
to this specific action which are addressed here, comments on the Draft 
PEA have been addressed in Appendix D of the Final PEA and are not 
repeated here. Copies of those comment letters and the responses to 
comments can be found at: https://www.mms.gov/alaska/. CBD also attached 
the comments submitted by EarthJustice on the 2007 DPEIS. Those 
comments are not substantially different from the comments submitted on 
the PEA and do not contain comments specific to the PGS project. 
Therefore, they are not addressed separately in this document. REDOIL 
attached the declaration of Rosemary Ahtuangaruak, a Native Alaskan 
resident in Nuiqsut, submitted on behalf of the plaintiffs in Native 
Village of Point Hope et al. v. Minerals Management Service et al.. 
Several of her statements are referenced in their comment letter and 
addressed in this section of the document. The majority of her 
statement relates to issues raised by other commenters regarding 
subsistence concerns.

General Concerns

    Comment 1: CBD urges NMFS not to issue a take authorization to PGS 
for the proposed activities unless and until the agency can ensure that 
mitigation measures are in place that truly avoid adverse impacts to 
all species and their habitats and only after full and adequate public 
participation has occurred and environmental review of the cumulative 
impacts of such activities on these species and their habitats has been 
undertaken. CBD, AEWC, and NSB feel that the proposed IHA does not meet 
these standards and therefore violates the MMPA, the Endangered Species 
Act (ESA), the National Environmental Policy Act (NEPA), and other 
governing statutes and regulations.
    Response: In its proposed IHA Federal Register notice (73 FR 34254, 
June 17, 2008), NMFS outlined in detail the proposed mitigation and 
monitoring requirements. The implementation of these measures will 
reduce the impacts of the proposed survey on marine mammals and their 
surrounding environment to the lowest level practicable. The public was 
given 30 days to review and comment on these measures, in accordance 
with section 101(a)(5)(D) of the MMPA. NMFS has prepared a SEA to the 
2006 MMS PEA. The PEA was available for comment in 2006. NMFS has 
fulfilled its obligations under NEPA by completing a SEA, which is not 
required to be available for public comment prior to its finalization. 
These documents fully analyze the cumulative impacts of seismic 
activity in the Arctic region. Additionally, NMFS completed a 
Biological Opinion in July, 2008, as required by section 7 of the ESA, 
which concluded that this action is not likely to jeopardize the 
continued existence of listed species or result in the destruction or 
adverse modification of critical habitat. The 2008 seismic survey off 
Oliktok Point in the Beaufort Sea has been analyzed pursuant to the 
ESA.
    Comment 2: CBD assumes that PGS is seeking authorization from the 
U.S. Fish and Wildlife Service (USFWS) for the take of polar bears and 
Pacific walrus that will occur from their proposed activities. While 
these species are outside of NMFS' jurisdiction for purposes of take 
authorization, they are clearly part of the ``affected environment'' 
adversely impacted by NMFS' action and therefore cannot lawfully be 
simply discounted, as NMFS has done in the proposed IHA.
    Response: Since the IHA issued by NMFS can only regulate take of 
species under NMFS' jurisdiction, the Notice of Proposed IHA does not 
go into detail regarding species under the jurisdiction of other 
Federal agencies. However, NMFS does analyze the impacts to these 
species in its NEPA analysis as part of the ``affected environment.'' 
The USFWS has issued a Letter of Authorization (LOA) to PGS to take 
species under its jurisdiction (i.e., polar bears and walruses).

[[Page 45971]]

    Comment 3: The NSB and AEWC point out that several sections of PGS' 
application were poorly researched and drafted, especially the sections 
on impacts to bowhead and beluga whales. REDOIL states that the 
modeling used by PGS was inadequate.
    Response: NMFS reviewed the application and considered it complete 
after PGS submitted an addendum on May 29, 2008. While information is 
lacking, NMFS conducted relevant research and made its own calculations 
so that accurate and complete information could be provided in the 
Federal Register notice for the proposed IHA (73 FR 34254, June 17, 
2008). In addition, detailed and updated information on bowhead whales 
and other Arctic Ocean marine mammal species is provided in the MMS 
2006 PEA, the MMS/NMFS 2007 DPEIS, the NMFS 2008 SEA, and the Stock 
Assessment Reports (SARs), as referenced in the proposed IHA notice.
    The addendum to PGS' application provided NMFS with additional 
information regarding the airgun array and the modeling used. NMFS used 
this information to calculate the various isopleths, which will be 
verified through sound source verification tests prior to beginning the 
survey. NMFS then used these recalculated radii to estimate take.
    Comment 4: The NSB states that PGS' application indicates it will 
take 90 days to complete the survey while the proposed IHA notice 
states it will take 75 days. Thus, the amount of activity that will 
occur is unclear. In addition, since the IHA will not be issued before 
mid-July at the earliest, the surveys are not likely to be completed by 
mid-September. Therefore, additional monitoring would be required, and 
PGS would need to consult with AEWC and sign a Conflict Avoidance 
Agreement (CAA). Without additional monitoring plans for September and 
October, the NSB opposes an IHA that permits seismic activity during 
that time period.
    Response: PGS will begin work upon receipt of the IHA and will work 
until approximately September 15. PGS, through ENI, has an agreement to 
complete operations by September 15 to allow another seismic program to 
begin. Although the project may extend beyond September 15 if the start 
date of other projects are pushed back, it is not anticipated to 
continue much beyond that date.
    PGS has agreed to conduct additional monitoring after August 25. 
Acoustic monitoring and aerial surveys will begin in late August (see 
``Monitoring and Reporting Plan'' section later in this document). This 
additional monitoring would continue until the PGS seismic survey is 
completed. Moreover, PGS signed a CAA with the AEWC on June 23, 2008.
    Comment 5: The AEWC indicates that PGS signed the CAA on June 23, 
2008 and that language about conducting activities near Nuiqsut was 
added specifically to address the village's concerns regarding both the 
bowhead whale migration and the potential effects of PGS' operations in 
nearshore areas used by Arctic Cisco, a fish commonly harvested by the 
community. The AEWC is satisfied with the negotiations and appreciates 
PGS' and ENI's willingness to work with them and their whaling 
captains.
    Response: NMFS has reviewed the CAA and agrees that the time 
limitations placed on activities inside and outside the barrier islands 
mitigates the potential impacts to subsistence activities in the area. 
This language has been added to the IHA as well.
    Comment 6: The AEWC and REDOIL are concerned about the lack of 
traditional knowledge in the application and NMFS' apparent failure to 
include this knowledge in reaching its conclusions.
    Response: While traditional knowledge is not often included in 
applications for IHAs in the Arctic, and while NMFS encourages 
applicants to include this information, NMFS uses a wide variety of 
information when making the determinations required under section 
101(a)(5)(D) of the MMPA and does not rely solely on the application. 
Traditional knowledge, for example, is discussed in several documents 
issued by MMS under NEPA, which were used by NMFS in making its MMPA 
determinations. In the case of the 2008 PGS IHA application, the MMS 
2006 PEA and MMS' Final EIS for the Alaska Outer Continental Shelf 
Beaufort Sea Planning Area Oil and Gas Lease Sales 186, 195, and 202 
(MMS 2003-001) and subsequent supporting NEPA documents, and NMFS' 2008 
Arctic Regional Biological Opinion (ARBO) provide NMFS with information 
on traditional knowledge that can be used, as here, when making 
determinations under NEPA and the MMPA.
    Comment 7: REDOIL incorporated CBD's comments by reference in their 
entirety, and the AEWC incorporated the NSB's comments by reference.
    Response: Comments submitted by CBD and the NSB are addressed in 
this section of the document.

MMPA Concerns

    Comment 8: CBD and the NSB state that because the proposed seismic 
activity carries the real potential to cause injury or death to marine 
mammals, neither an IHA nor a LOA (because NMFS has not promulgated 
regulations for mortality by seismic activities) can be issued for PGS' 
proposed activities.
    Response: Section 101(a)(5)(D) of the MMPA authorizes Level A 
(injury) harassment and Level B (behavioral) harassment takes. While 
NMFS' regulations indicate that a LOA must be issued if there is a 
potential for serious injury or mortality, NMFS does not believe that 
PGS' seismic surveys require issuance of a LOA. As explained throughout 
this Federal Register Notice, it is highly unlikely that marine mammals 
would be exposed to sound pressure levels (SPLs) that could result in 
serious injury or mortality. The best scientific information indicates 
that an auditory injury is unlikely to occur as apparently sounds need 
to be significantly greater than 180 dB for injury to occur (Southall 
et al., 2007). NMFS has determined that exposure to several seismic 
pulses at received levels near 200-205 dB (rms) might result in slight 
temporary threshold shift (TTS) in hearing in a small odontocete, 
assuming the TTS threshold is a function of the total received pulse 
energy. Seismic pulses with received levels of 200-205 dB or more are 
usually restricted to a radius of no more than 200 m (656 ft) around a 
seismic vessel operating a large array of airguns. PGS' airgun array is 
considered to be of moderate size. For baleen whales, while there are 
no data, direct or indirect, on levels or properties of sound that are 
required to induce TTS, there is a strong likelihood that baleen whales 
(bowhead and gray whales) would avoid the approaching airguns (or 
vessel) before being exposed to levels high enough for there to be any 
possibility of onset of TTS. For pinnipeds, information indicates that 
for single seismic impulses, sounds would need to be higher than 190 dB 
rms for TTS to occur while exposure to several seismic pulses indicates 
that some pinnipeds may incur TTS at somewhat lower received levels 
than do small odontocetes exposed for similar durations. Consequently, 
NMFS has determined that it would be lawful to issue an IHA to PGS for 
the 2008 seismic survey program.
    Comment 9: CBD and the NSB state that while PGS' application does 
generally describe the location and duration of the seismic activities 
themselves, there is minimal description and no analysis of the impacts 
on marine mammals of the transport and deployment of the 13 vessels 
that will be involved in the

[[Page 45972]]

survey. By failing to adequately specify the activities and impacts of 
these vessels, PGS has failed to comply with 16 U.S.C. 1371(a)(5)(D)(i) 
and 50 CFR 216.104(a)(2).
    Response: The specified activity that has been proposed and for 
which an IHA has been requested is the use of seismic airguns to 
conduct oil and gas exploration. While the support vessels play a role 
in facilitating seismic operations, NMFS does not expect these 
operations to result in the incidental take of marine mammals. The 
majority of the vessels to be used in the seismic survey will be 
transported to the North Slope via trucks. Moreover, any vessels to be 
used in the seismic survey are typically slow-moving, and therefore, 
any risk of vessel collisions with marine mammals is expected to be 
minimal. Additionally, since marine mammal observers (MMOs) will be 
scanning the area for marine mammals during seismic operations, this 
further reduces the risk of a collision with cetaceans or pinnipeds. 
PGS has also agreed to hire Inupiat speakers to work on the seismic 
vessels. As part of their duties, the Inupiat speakers will be required 
to watch for marine mammals. Finally, normal shipping and transit 
operations do not rise to a level requiring an authorization under the 
MMPA. To require IHAs and LOAs for standard shipping would reduce the 
ability of NMFS to review activities that have a potential to cause 
harm to marine mammal populations.
    Comment 10: The NSB and CBD are concerned that NMFS has not made 
separate findings for both small numbers and negligible impact (16 
U.S.C. 1371(a)(5)(D)(i)(I); 50 CFR 206.107). CBD states that the 
closest thing to a separate ``small numbers'' finding is a single 
sentence in the Preliminary Conclusions section of the proposed IHA. In 
recent proposed IHAs, NMFS has directly cited its invalid ``small 
numbers'' definition. In the current IHA, NMFS does not directly cite 
to the regulatory definition of ``small numbers'', but nevertheless 
conducts its analysis according to this invalid standard. Yet neither 
the Federal Register document nor PGS' application provide any support 
whatsoever for this ``conclusion.'' The CBD continues that for PGS' 
proposed seismic surveys in the Beaufort Sea, the number of marine 
mammals likely to be exposed to sounds of 160 dB re 1 microPa (rms) or 
greater, and therefore ``harassed'' according to NMFS' operative 
thresholds, is almost 1,600. In absolute terms this number cannot be 
considered ``small.'' The proposed seismic surveys simply are not 
designed to avoid impacting more than small numbers of marine mammals, 
and, therefore, the IHA must be denied.
    Response: NMFS believes that the small numbers requirement has been 
satisfied. The species most likely to be harassed during seismic 
surveys off Oliktok Point in the Beaufort Sea is the ringed seal, with 
an ``average estimate'' of 3,551 exposures to SPLs of 160 dB or 
greater. (The estimate contained in the proposed IHA notice (73 FR 
34254, June 17, 2008) was 1,467 ringed seals. However, this estimate 
was based on exposures to SPLs of 170 dB or greater.) This does not 
mean that this is the number of ringed seals that will actually exhibit 
a disruption of behavioral patterns in response to the sound source; 
rather, it is simply the best estimate of the number of animals that 
potentially could have a behavioral modification due to the noise. For 
example, Moulton and Lawson (2002) indicate that most pinnipeds exposed 
to seismic sounds lower than 170 dB do not visibly react to that sound, 
and, therefore, pinnipeds are not likely to react to seismic sounds 
unless they are greater than 170 dB re 1 microPa (rms). In addition, 
these estimates are calculated based upon line miles of survey effort, 
animal density, and the calculated zone of influence (ZOI). While this 
methodology is valid for seismic surveys that transect long distances, 
for those surveys that ``mow the lawn'' (that is, remain within a 
relatively small area, transiting back and forth while shooting 
seismic), the take estimate numbers tend to be highly inflated because 
animals that might have been affected (taken) are likely to have moved 
out of the area to avoid additional annoyance from the seismic sounds 
(assuming they were taken in the first place).
    The Level B harassment take estimate of 3,551 ringed seals is a 
small number, at least in relative terms, in that it represents only 
1.4 percent of the regional stock size of that species (249,000), if 
each ``exposure'' at 160 dB represents an individual ringed seal. The 
percentage would be even lower if a higher SPL is required for a 
behavioral reaction (as is expected) or, if as expected, animals move 
out of the seismic area. As a result, NMFS believes that these 
``exposure'' estimates are conservative, and seismic surveys will 
actually affect less than 1.4 percent of the Beaufort Sea ringed seal 
population.
    The ``average estimates'' of exposures for the remaining species 
that could potentially occur in the project area (i.e., beluga, 
bowhead, and gray whales and bearded and spotted seals) are only 
between 25 and 178 animals, which constitute at most 0.3 percent of any 
of these five species populations in the Arctic. Additionally, the 
presence of beluga, bowhead, and gray whales in the shallow water 
environment within the barrier islands is possible but expected to be 
very limited.
    Further, NMFS believes that it is incorrect to add the number of 
exposures together to support an argument that the numbers are not 
``small.'' The MMPA is quite clear ''...taking by harassment of small 
numbers of marine mammals of a species or population stock...'' does 
not refer to an additive calculation (small numbers, not small number).
    Separate detailed analyses on the levels of take by noise exposure 
and cumulative impacts to these marine mammal species and stocks from a 
wide spectrum in the past, current, and foreseeable future were also 
conducted and described in the Federal Register notice of the proposed 
IHA (73 FR 34254, June 17, 2008), the MMS 2006 PEA, and the NMFS 2008 
SEA. These analyses led NMFS to conclude that while behavioral 
modifications, including temporarily vacating the area during the 
project period may be made by these species to avoid the resultant 
acoustic disturbance, NMFS nonetheless found that this action would 
result in no more than a negligible impact on the affected marine 
mammal species and/or stocks.
    In sum, NMFS concludes that PGS' 3D OBC/TZ seismic survey will only 
result in the taking, by incidental harassment, of small numbers of 
marine mammals of a species or stock and would result in a negligible 
impact on such species or stock(s).
    Comment 11: CBD states that in 2006, NMFS required surveys of a 
120-dB safety zone for bowhead cow/calf pairs and ``large groups'' 
(greater than 12 individuals). If 12 bowheads constitute a ``large 
group,'' we do not see how the numerous bowheads that will be harassed 
by PGS are a ``small number.'' This displacement and the disruption of 
pod integrity clearly constitute harassment under the MMPA. PGS' 
activities can be expected to have similar effects. NMFS' determination 
that PGS' activities will have a ``negligible impact'' does not 
withstand scrutiny. First, as explained above and in our NEPA comments, 
the calculation of numbers of marine mammals harassed by PGS is likely 
an underestimate as it relies on a received sound threshold (160/170 
dB) that is too high. Any negligible impacts determination based on 
such flawed data is itself unsupportable. Moreover, NMFS has previously 
recognized a harassment threshold of 120 dB for

[[Page 45973]]

continuous sounds. Given that PGS is using 13 vessels, the engine and 
operating noise from these vessels should be treated as ``continuous'' 
for purposes of estimating harassment thresholds. The MMPA is 
precautionary. In making its determinations, NMFS must give the benefit 
of the doubt to the species. As the D.C Circuit has repeatedly stated, 
``it is clear that ``the Act was to be administered for the benefit of 
the protected species rather than for the benefit of commercial 
exploitation'' (Kokechik Fishermen's Association v. Secretary of 
Commerce, 839 F.2d 795, 800 (D.C. Cir. 1988) citing Committee for 
Humane Legislation, Inc. v. Richardson, 540 F.2d 1141, 1148 (D.C. Cir. 
1976)). NMFS seems to be ignoring this mandate in analyzing the impacts 
of PGS' activities.
    Response: On CBD's first point, there is no relationship between 
the term ``large group'' and ``small numbers.'' The first term refers 
to a number of 12 or more in order to implement additional mitigation 
measures, the second to a concept found in the MMPA, which has been 
addressed previously in this notice. NMFS agrees that while the 
``displacement and the disruption of pod integrity constitute 
harassment under the MMPA,'' NMFS is unaware of any information that 
seismic survey operations will result in bowhead whale pod integrity 
disruption. On the contrary, traditional knowledge indicates that when 
migrating bowhead whales encounter anthropogenic noises, as a group 
they all divert away from the noise and continue to do so even if the 
noise ceases.
    Secondly, NMFS does not agree that the sources used in PGS' 
activity should be considered ``continuous.'' The airgun arrays are the 
primary noise source that could potentially impact marine mammals. As 
stated previously in this document, NMFS does not issue IHAs for simple 
vessel traffic.
    The decision in Kokechik Fishermen's Association v. Secretary of 
Commerce, 839 F.2d 795 (D.C. Circ. 1988), does not apply to this case 
because it is factually and legally distinguishable. The incidental 
take permit challenged in Kokechik was for commercial fishing 
operations, governed by section 101(a)(2) of the MMPA, whereas the 
incidental authorization that is the subject of this IHA is for an 
activity other than commercial fishing and is appropriately authorized 
pursuant to section 101(a)(5)(D). Consequently, as discussed throughout 
this document, it is not unlawful for NMFS to apply section 
101(a)(5)(D) when issuing an IHA to PGS for the take of marine mammals 
incidental to seismic surveys.
    Comment 12: Additionally, CBD and NSB state that NMFS has no idea 
of the actual population status of several of the species subject to 
the proposed IHA. For example, in the most recent SARs prepared 
pursuant to the MMPA, NMFS acknowledges it has no accurate information 
on the status of ribbon, spotted, bearded, and ringed seals. CBD and 
NSB both indicate that without this data, NMFS cannot make a rational 
``negligible impact'' finding. This is particularly so given there is 
real reason to be concerned about the status of these populations. Such 
concerns were raised in a recent letter to NMFS from the Commission 
following the Commission's 2005 annual meeting in Anchorage, Alaska 
(Commission, January 25, 2006 Letter). With regard to these species, 
the MMC cautioned against assuming a stable population.
    On December 20, 2007, CBD petitioned NMFS to list the ribbon seal 
under the ESA due to the loss of its sea-ice habitat from global 
warming and the adverse impacts of oil industry activities on the 
species. On May 27, 2008, CBD submitted a similar petition seeking 
listing of the spotted, bearded, and ringed seals. We request that NMFS 
consider the information contained in these petitions, as well as other 
information in its files on the status of these species, when analyzing 
the impacts of the proposed IHA on these increasingly imperiled 
species. Because the status of the ribbon, spotted, ringed, and bearded 
seals and other stocks is unknown, NMFS cannot conclude that surveys 
which will harass untold numbers of individuals of each species will 
have no more than a ``negligible effect'' on the stocks.
    Response: As required by the MMPA implementing regulations at 50 
CFR 216.102(a), NMFS has used the best scientific information available 
in making its determinations required under the MMPA. The Alaska SAR 
provides population estimates based on past survey work conducted in 
the region. PGS' survey is not expected to have adverse impacts on ice 
seals. The activity will last for approximately 75 days in the open-
water environment of the Beaufort Sea. On March 28, 2008, NMFS 
published a notice of a 90-day petition finding, request for 
information, and initiation of status reviews of ribbon, bearded, 
ringed, and spotted seals (73 FR 16617). The comment period for this 
action closed on May 27, 2008. NMFS is currently reviewing all relevant 
information and within 1 year of receipt of the petition, NMFS shall 
conclude the review with a finding as to whether or not the petitioned 
action is warranted. The ribbon seal petition submitted in December, 
2007, is not relevant for this survey, as ribbon seals are not found in 
the project area. Information contained in the May, 2008, petition does 
not provide sufficient evidence that NMFS' preliminary determination 
that only small numbers of ringed, bearded, and spotted seals would be 
affected as a result of PGS' seismic activity is invalid.
    Comment 13: CBD states that the analyses in the proposed IHA are 
largely confined to looking at the immediate effects of PGS' airgun 
surveys in the Beaufort Sea on several marine mammal species. However, 
there is no analysis of the impacts of the 13 vessels and any related 
aircraft participating in the surveys on marine mammals. The impacts of 
these activities must be analyzed and mitigated before any ``negligible 
impact'' finding can be made. CBD and NSB believe that NMFS must 
consider these effects together with other oil and gas activities that 
affect these species, stocks and local populations, other anthropogenic 
risk factors such as climate change, and the cumulative effect of these 
activities over time. The effects should be analyzed with respect to 
their potential population consequences at the species level, stock 
level, and at the local population level.
    Response: Under section 101(a)(5)(D) of the MMPA, NMFS is required 
to determine whether the taking by the applicant's specified activity 
will have a negligible impact on the affected marine mammal species or 
population stocks. Cumulative impact assessments are NMFS' 
responsibility under NEPA, not the MMPA. In that regard, the MMS Final 
PEA and NMFS 2008 SEA address cumulative impacts. The Final PEA's 
cumulative activities scenario and cumulative impact analysis focused 
on oil and gas-related and non-oil and gas-related noise-generating 
events/activities in both Federal and State of Alaska waters that were 
likely and foreseeable. Other appropriate factors, such as Arctic 
warming, military activities, and noise contributions from community 
and commercial activities were also considered. Appendix D of the Final 
PEA addresses similar comments on cumulative impacts, including global 
warming. That information was incorporated into and updated in the NMFS 
2008 SEA and into this document by citation. NMFS adopted the MMS Final 
PEA, and it is part of NMFS' Administrative Record.
    NMFS does not require authorizations under section 101(a)(5) of the 
MMPA for normal shipping or transit. A further

[[Page 45974]]

explanation was addressed in the response to Comment 9.
    Comment 14: NSB and CBD are both concerned about cumulative impacts 
from multiple operations. PGS' proposal is only one of numerous oil 
industry activities recently occurring, planned, or ongoing in the U.S. 
portions of the Chukchi and Beaufort Seas. No analysis of seismic 
surveys in the Russian or Canadian portions of the Chukchi and Beaufort 
seas is mentioned either. Similarly, significant increases in onshore 
oil and gas development with attendant direct impacts and indirect 
impacts on marine mammals such as through increased ship traffic are 
also occurring and projected to occur at greater rates than in the past 
(e.g., NMFS' IHA for barge traffic to NPR-A; IHA for barge operations 
in the Beaufort Sea; and a notice regarding new oil and gas development 
in the NPR-A). CBD states that further cumulative effects impacting the 
marine mammals of the Beaufort and Chukchi Seas are outlined in their 
NEPA comments on the MMS PEA and the DPEIS.
    The NSB points out that in addition to the proposed offshore 
industrial operations listed above, there will be supply and fuel 
barging to villages, barging for support of onshore development and 
exploration, scientific cruises, climate change studies, USCG 
operations, tourist vessel traffic, and other activities as well. The 
cumulative impacts of all these activities must be factored into any 
negligible impact determination. Further, without an analysis of the 
effects of all of the planned operations, it is impossible to determine 
whether the monitoring plans are sufficient.
    Response: See the response to the previous comment. The issue of 
cumulative impacts has been addressed in the 2006 MMS Final PEA and the 
2008 NMFS SEA.
    Comment 15: According to CBD, another factor causing NMFS' 
``negligible impact'' findings to be suspect is the fact that the 
Beaufort Sea area is undergoing rapid change as a result of global 
warming. For species under NMFS' jurisdiction, and therefore subject to 
the proposed IHA, seals are likely to face the most severe 
consequences. The Arctic Climate Impact Assessment (ACIA) concluded 
that ringed, spotted, and bearded seals would all be severely 
negatively impacted by global warming this century. The ACIA stated 
that ringed seals are particularly vulnerable (ACIA, 2004). In 2003, 
the NRC noted that oil and gas activities combined with global warming 
presented a serious cumulative impact to the species. NMFS' failure to 
address global warming as a cumulative effect renders its negligible 
impact findings invalid.
    Response: Under section 101(a)(5)(D) of the MMPA, ``the Secretary 
shall authorize... taking by harassment of small numbers of marine 
mammals of a species or population stock by such citizens while 
engaging in that activity within that region if the Secretary finds 
that such harassment during each period concerned (I) will have a 
negligible impact on such species or stock, and (II) will not have an 
unmitigable adverse impact on the availability of such species or stock 
for taking for subsistence uses.'' Section 101(a)(5)(D) of the MMPA 
does not require NMFS to base its negligible impact determination on 
the possibility of cumulative effects of other actions.
    As stated in previous responses, cumulative impact assessments are 
NMFS' responsibility under NEPA, not the MMPA. In that regard, the MMS 
2006 Final PEA and NMFS' 2008 SEA address cumulative impacts. The PEA's 
cumulative activities scenario and cumulative impact analysis focused 
on oil and gas-related and non-oil and gas-related noise-generating 
events/activities in both Federal and State of Alaska waters that were 
likely and foreseeable. Other appropriate factors, such as Arctic 
warming, military activities, and noise contributions from community 
and commercial activities were also considered. Appendix D of the PEA 
addresses similar comments on cumulative impacts, including global 
warming. That information was incorporated into and updated in the NMFS 
2008 SEA and into this document by citation. NMFS adopted the MMS Final 
PEA, and it is part of NMFS' Administrative Record.

Marine Mammal Impact Concerns

    Comment 16: CBD states that they referenced the scientific 
literature linking seismic surveys with marine mammal stranding events 
in its comments to MMS on the 2006 Draft PEA and in comments to NMFS 
and MMS on the 2007 DPEIS. NMFS' failure to address these studies and 
the threat of serious injury or mortality to marine mammals from 
seismic surveys renders NMFS' conclusory determination that serious 
injury or morality will not occur from PGS' activities arbitrary and 
capricious.
    Response: MMS briefly addressed the humpback whale stranding in 
Brazil on page PEA-127 in the Final PEA. Marine mammal strandings are 
also discussed in the NMFS/MMS DPEIS. A more detailed response to the 
cited strandings has been provided in several previous IHA issuance 
notices for seismic surveys (e.g., 71 FR 50027, August 24, 2006; 73 FR 
40512, July 15, 2008). Additional information has not been provided by 
CBD or others regarding these strandings. As NMFS has stated, the 
evidence linking marine mammal strandings and seismic surveys remains 
tenuous at best. Two papers, Taylor et al. (2004) and Engel et al. 
(2004), reference seismic signals as a possible cause for a marine 
mammal stranding. Taylor et al. (2004) noted two beaked whale stranding 
incidents related to seismic surveys. The statement in Taylor et al. 
(2004) was that the seismic vessel was firing its airguns at 1300 hrs 
on September 24, 2004, and that between 1400 and 1600 hrs, local 
fishermen found live-stranded beaked whales some 22 km (12 nm) from the 
ship's location. A review of the vessel's trackline indicated that the 
closest approach of the seismic vessel and the beaked whales' stranding 
location was 33 km (18 nm) at 1430 hrs. At 1300 hrs, the seismic vessel 
was located 46 km (25 nm) from the stranding location. What is unknown 
is the location of the beaked whales prior to the stranding in relation 
to the seismic vessel, but the close timing of events indicates that 
the distance was not less than 33 km (18 nm). No physical evidence for 
a link between the seismic survey and the stranding was obtained. In 
addition, Taylor et al. (2004) indicate that the same seismic vessel 
was operating 500 km (270 nm) from the site of the Galapagos Island 
stranding in 2000. Whether the 2004 seismic survey caused two beaked 
whales to strand is a matter of considerable debate (see Cox et al., 
2004). NMFS believes that scientifically, these events do not 
constitute evidence that seismic surveys have an effect similar to that 
of mid-frequency tactical sonar. However, these incidents do point to 
the need to look for such effects during future seismic surveys. To 
date, follow-up observations on several scientific seismic survey 
cruises have not indicated any beaked whale stranding incidents.
    Engel et al. (2004), in a paper presented to the International 
Whaling Commission (IWC) in 2004 (SC/56/E28), mentioned a possible link 
between oil and gas seismic activities and the stranding of eight 
humpback whales (seven off the Bahia or Espirito Santo States and one 
off Rio de Janeiro, Brazil). Concerns about the relationship between 
this stranding event and seismic activity were raised by the 
International Association of Geophysical Contractors (IAGC). The IAGC 
(2004) argues that not enough

[[Page 45975]]

evidence is presented in Engel et al. (2004) to assess whether or not 
the relatively high proportion of adult strandings in 2002 is 
anomalous. The IAGC contends that the data do not establish a clear 
record of what might be a ``natural'' adult stranding rate, nor is any 
attempt made to characterize other natural factors that may influence 
strandings. As stated previously, NMFS remains concerned that the Engel 
et al. (2004) article appears to compare stranding rates made by 
opportunistic sightings in the past with organized aerial surveys 
beginning in 2001. If so, then the data are suspect.
    Second, strandings have not been recorded for those marine mammal 
species expected to be harassed by seismic in the Arctic Ocean. Beaked 
whales and humpback whales, the two species linked in the literature 
with stranding events with a seismic component are not located in the 
area of the Beaufort Sea where seismic activities would occur (although 
humpback whales have been spotted in the Chukchi Sea and much farther 
west in the Beaufort Sea). Moreover, NMFS notes that in the Beaufort 
Sea, aerial surveys have been conducted by MMS and industry during 
periods of industrial activity (and by MMS during times with no 
activity). No strandings or marine mammals in distress have been 
observed during these surveys; nor reported by NSB inhabitants. 
Finally, if bowhead and gray whales react to sounds at very low levels 
by making minor course corrections to avoid seismic noise and 
mitigation measures require PGS to ramp-up the seismic array to avoid a 
startle effect, strandings are highly unlikely to occur in the Arctic 
Ocean. Ramping-up of the array will allow marine mammals the 
opportunity to vacate the area of ensonification and thus avoid any 
potential injury or impairment of their hearing capabilities. In 
conclusion, NMFS does not expect any marine mammals will incur serious 
injury or mortality as a result of seismic surveys in the Beaufort Sea 
in 2008.
    Comment 17: CBD states that seismic surveys pose the risk of 
permanent hearing loss by marine mammals, which itself is a ``serious 
injury'' likely to lead to the death of these animals. Seismic pulses 
of sufficient volume, such as those proposed to be used by PGS, have 
the potential to cause temporary and permanent hearing loss in marine 
mammals.
    Response: NMFS does not expect that animals will be injured, or for 
that matter seriously injured or killed, if they are within the 180 dB 
(cetaceans) and 190 dB (pinnipeds) isopleths. These criteria were set 
to approximate where Level A harassment (defined as ``any act of 
pursuit, torment or annoyance which has the potential to injure a 
marine mammal or marine mammal stock in the wild'') from acoustic 
sources begins. NMFS has determined that a TTS, which is the mildest 
form of hearing impairment that can occur during exposures to a strong 
sound may occur at these levels. For sound exposures at or somewhat 
above TTS, hearing sensitivity recovers rapidly after exposure to the 
noise ends. Few data on sound levels and durations necessary to elicit 
mild TTS have been obtained for marine mammals, and none of the 
published data concern TTS elicited by exposure to multiple pulses of 
sound. TTS is not an injury, as there is no injury to individual cells.
    As NMFS has published several times in Federal Register notices 
regarding issuance of IHAs for seismic survey work or in supporting 
documentation for such authorizations, for whales exposed to single 
short pulses, the TTS threshold appears to be a function of the energy 
content of the pulse. Given the data available at the time of the IHA 
issuance, the received level of a single seismic pulse might need to be 
approximately 210 dB re 1 Pa rms in order to produce brief, mild TTS. 
Exposure to several seismic pulses at received levels near 200-205 dB 
(rms) might result in slight TTS in a small odontocete, assuming the 
TTS threshold is a function of the total received pulse energy. Seismic 
pulses with received levels of 200-205 dB or more are usually 
restricted to a radius of no more than 200 m (656 ft) around a seismic 
vessel operating a large array of airguns. Since PGS is operating a 
moderate-sized array, this radius would be even smaller. For baleen 
whales, there are no data, direct or indirect, on levels or properties 
of sound that are required to induce TTS. However, there is a strong 
likelihood that baleen whales (bowhead and gray whales) would avoid the 
approaching airguns (or vessel) before being exposed to levels high 
enough for there to be any possibility of onset of TTS.
    A marine mammal within a radius of 100 m (328 ft) or less around a 
typical large array of operating airguns may be exposed to a few 
seismic pulses with levels greater than or equal to 205 dB and possibly 
more pulses if the marine mammal moves with the seismic vessel. When 
permanent threshold shift (PTS) occurs, there is physical damage to the 
sound receptors in the ear. In some cases, there can be total or 
partial deafness, whereas in other cases, the animal has an impaired 
ability to hear sounds in specific frequency ranges. However, there is 
no specific evidence that exposure to pulses of airgun sound can cause 
PTS in any marine mammal, even with airgun arrays larger than that 
proposed to be used in PGS' survey. Given the possibility that mammals 
close to an airgun array might incur TTS, there has been further 
speculation about the possibility that some individuals occurring very 
close to airguns might incur PTS. Single or occasional occurrences of 
mild TTS are not indicative of permanent auditory damage in terrestrial 
mammals. Relationships between TTS and PTS thresholds have not been 
studied in marine mammals but are assumed to be similar to those in 
humans and other terrestrial mammals.
    The information provided here regarding PTS is for large airgun 
arrays. PGS is proposing to use an 880 in3 array, which is considered 
mid-size. Therefore, animals would have to be very close to the vessel 
to incur serious injuries. Because of the monitoring and mitigation 
measures required in the IHA (i.e., MMOs, ramp-up, power-down, 
shutdown, etc.), it is expected that appropriate corrective measures 
can be taken to avoid any injury, including serious injury.
    Comment 18: The NSB DWM states that humpback and fin whales were 
seen in the Beaufort and Chukchi Seas in 2007. Therefore, it is 
reasonable to expect that both of these species could occur in the 
vicinity of Harrison Bay in 2008. Given that both species are 
endangered, NMFS should include an evaluation of potential impacts to 
humpback and fin whales from PGS' proposed seismic activities and other 
oil and gas activities planned for 2008. Narwhals have also been seen 
in the vicinity of PGS' operations. Several years ago, hunters observed 
several narwhals in the vicinity of Thetis Island (E. Nukapigak, pers. 
comm.), which is in the area proposed for seismic surveys. Potential 
impacts to narwhals should also be evaluated.
    Response: As an initial matter, NMFS prepared a Biological Opinion 
in July, 2008, to assess the effects of oil and gas exploration in the 
Arctic Ocean, particularly in light of new sightings data for fin and 
humpback whales. Until 2007, historic and recent information did not 
indicate humpback whales inhabit northern portions of the Chukchi Sea 
or enter the Beaufort Sea. No sightings of humpback whales were 
reported during aerial surveys of endangered whales in summer (July) 
and autumn (August-October) of 1979-1987 in the Northern Bering Sea 
(from north of St. Lawrence Island), the

[[Page 45976]]

Chukchi Sea north of lat. 66[deg] N. and east of the International Date 
Line, and the Alaskan Beaufort Sea from long. 157[deg] 01' W. east to 
long. 140[deg] W. and offshore to lat. 72[deg] N. (Ljungblad et al., 
1988). Humpbacks have not been observed during annual aerial surveys of 
the Beaufort Sea conducted in September and October from 1982-2007 
(e.g., Monnett and Treacy, 2005; Moore et al., 2000; Treacy, 2002; 
Monnett, 2008, pers. comm.). During a 2003 research cruise in which all 
marine mammals observed were recorded from July 5 to August 18 in the 
Chukchi and Beaufort Seas, no humpback whales were observed (Bengtson 
and Cameron, 2003). One observation of a single humpback whale was 
recorded in 2006 by MMOs aboard a vessel in the southern Chukchi Sea 
outside of the Chukchi Sea Planning Area (Patterson et al., 2007; MMS, 
2006, unpublished data). During summer 2007 between August 1 and 
October 16, humpback whales were observed during seven observation 
sequence events in the western Alaska Beaufort Sea (1 animal) and 
eastern and southeastern Chukchi Sea (6 animals; MMS, 2007, unpublished 
data) and one other observation in the southern Chukchi Sea in 2007 
(Sekiguchi, In prep.). The one humpback sighting in the Beaufort Sea in 
2007 was in Smith Bay, which is more than 150 km (100 mi) west of the 
PGS project area. Therefore, humpback whales are not expected to occur 
in the location of PGS' survey.
    Additionally, there is no indication that fin whales typically 
occur within the project area. There have been only rare observations 
of fin whales into the eastern half of the Chukchi Sea. Fin whales have 
not been observed during annual aerial surveys of the Beaufort Sea 
conducted in September and October from 1982-2007 (e.g., Monnett and 
Treacy, 2005; Moore et al., 2000; Treacy, 2002; Monnett, 2008, pers. 
comm.). During a research cruise in the Chukchi and Beaufort seas (from 
July 5-August 18, 2003), in which all marine mammals observed were 
recorded, no fin whales were observed (Bengtson and Cameron, 2003). 
Therefore, fin whales are not expected to occur in the location of PGS' 
survey.
    Discussions at this year's Open-water Meeting in Anchorage, Alaska, 
in April, in which the NSB participated, indicated that narwhals are 
extremely unlikely to occur in the U.S. Beaufort Sea and mainly inhabit 
the Canadian Beaufort Sea. At present, NMFS does not have a SAR 
available for narwhal, making it difficult to assess distribution and 
abundance of the narwhal in the Alaskan Beaufort Sea. Therefore, it is 
highly unlikely that narwhals would be affected by the survey.
    Comment 19: The NSB DWM states that contrary to the information 
contained in PGS' application, some bowhead whales spend the summer in 
the Beaufort Sea. Thus, evaluation of the potential for impact from 
seismic surveys on summering whales is needed.
    Response: NMFS conducted this analysis in its NEPA documents. 
Although it is possible that bowhead whales could occur inside the 
barrier islands, the extremely shallow water in which PGS will operate 
(less than 15 m, 49 ft) is not suitable bowhead habitat. Mitigation and 
monitoring measures required in the IHA will also help to reduce 
impacts to bowheads throughout the entire time period of the survey.
    Comment 20: CBD and the NSB state that NMFS' estimate of the number 
of marine mammals that may be harassed under the proposed authorization 
is based on the assumption that sounds below 160 dB re 1 microPa (rms) 
do not constitute harassment. This assumption is incorrect, and 
therefore PGS' and NMFS' estimated take numbers represent an 
underestimate of the possible true impact. In our NEPA comments on the 
2006 PEA, we pointed out the numerous studies showing significant 
behavioral impacts from received sounds well below 160 dB. Even the 
2006 PEA itself acknowledges that impacts to bowheads occur at levels 
of 120 dB and below. This clearly meets the statutory definition of 
harassment and demonstrates that the numbers of bowhead estimated in 
the proposed IHA to be taken by PGS' activities likely constitute a 
significant underestimate. NMFS' ``small numbers'' conclusion is 
therefore arbitrary and capricious for this reason as well.
    The NSB DWM questions why PGS does not acknowledge that bowheads 
avoided an area around active seismic to much lower sound levels, down 
to 120 dB or lower (Richardson et al., 1999). Bowheads' sensitivity to 
very low level of industrial sounds must be considered in assessing 
impacts from one industrial operation, as well as impacts from 
cumulative impacts from multiple operations.
    Response: On the first point, NMFS uses the best science available 
when making its determinations under section 101(a)(5)(D) of the MMPA. 
On the second point, CBD misunderstands the purpose of ``potential to 
harass'' in the MMPA. This was not meant to mean that highly 
speculative numbers of marine mammals could ``potentially be harassed'' 
but that Congress intended for U.S. citizens to apply for an MMPA 
authorization prior to its activity taking marine mammals, not waiting 
until after the taking occurred and someone needed to ``prove'' that 
the taking happened.
    As stated previously, the ``take'' numbers provided in the proposed 
IHA notice (73 FR 34254, June 17, 2008) and subsequently amended herein 
are considered the numbers of animals that could potentially be 
``exposed'' to the sounds based on species density, the area 
potentially affected, and the length of time the noise would be 
expected to last. This does not necessarily indicate that all animals 
will have a significant behavioral reaction to that sound at the level 
of 160 dB. In addition, CBD took the maximum number of marine mammals 
(based on animal density), instead of the expected density (as 
explained in PGS' application). Using maximum density estimates is 
problematic as it tends to inflate harassment take estimates to an 
unreasonably high number and is not based on empirical science. As a 
result, NMFS believes that far fewer marine mammals would receive SPLs 
sufficient to cause a significant biological reaction by the species. 
In regard to bowhead whales, while this species reacts to sounds at 
levels lower than 160 dB, during its fall westward migration (but not 
while in a non-migratory behavior), those reactions are not detectable 
by MMOs and that information is obtained only later during computer 
analysis of collected data.
    Richardson et al. (1999) monitored the reactions of migrating 
bowhead whales and found that most avoided the area of seismic activity 
within 20 km (12.4 mi) of the source at levels as low as 120-130 dB 
(rms). Also, the Northstar recordings are conducted during the fall 
migration westward across the Beaufort. Since some of the work to be 
conducted by PGS will overlap with the bowhead migration period, 
beginning on August 25, PGS will be required to monitor out to the 120-
dB isopleth. This will be done via vessel and aerial surveys. PGS will 
be required to shutdown operations if 4 or more cow/calf pairs are seen 
within this radius. PGS will conduct sound source verification tests at 
the beginning of the survey to determine the exact distances to the 
190-, 180-, 160-, and 120-dB isopleths both inside and outside the 
barrier islands.
    Lastly, the requirement to assess cumulative impacts is required 
under NEPA, not the MMPA. Cumulative impacts were assessed and analyzed 
in both the 2006 PEA and the 2008 SEA.
    Comment 21: The NSB DWM, CBD, and REDOIL state that a 160-dB 
threshold for belugas is similarly

[[Page 45977]]

flawed. As NMFS is aware, belugas are among the most sensitive of 
marine mammals to anthropogenic sound. In previous IHA notices, NMFS 
has acknowledged the impacts of sounds on belugas even at significant 
distances from a sound source. For example, in a recent proposed take 
authorization related to seismic surveys by NSF, NMFS noted that 
belugas can be displaced at distances of up to 20 km (12.4 mi) from a 
sound source. Aerial surveys during seismic operations in the 
southeastern Beaufort Sea recorded much lower sighting rates of beluga 
whales within 10-20 km (6.2-12.4 mi) of an active seismic vessel. These 
results were consistent with the low number of beluga sightings 
reported by observers aboard the seismic vessel. Such displacement 
clearly meets the statutory definition of harassment and demonstrates 
that the number of belugas estimated to be taken by PGS' activities 
constitutes a significant underestimate. Belugas are also extremely 
sensitive to ships. A study of Canadian belugas showed flight responses 
from ice-breakers at received sound levels as low as 94 dB. Presumed 
alarm vocalizations of belugas indicated that they were aware of an 
approaching ship over 80 km (50 mi) away and they showed strong 
avoidance reactions to ships approaching at distances of 35-50 km (22-
31 mi) when received noise levels ranged from 94 to 105 dB re 1 Pa in 
the 20-1000 Hz band. The ``flee'' response of the beluga involved large 
herds undertaking long dives close to or beneath the ice edge; pod 
integrity broke down and diving appeared asynchronous. Belugas were 
displaced along ice edges by as much as 80 km (50 mi; Finley et al., 
1990). The NSB DWM states that the 120-dB zone should be used for 
estimating numbers of beluga whales that may be taken during seismic 
operations in the Beaufort Sea.
    The NSB DWM notes that while most beluga whales are found near the 
shelf break, they are also regularly seen in shallower nearshore waters 
of the Beaufort Sea.
    Response: Much of the Beaufort Sea seasonal population of belugas 
enters the Mackenzie River estuary (in Canada) for a short period from 
July through August to molt their epidermis, but they spend most of the 
summer in offshore waters of the eastern Beaufort Sea, Amundsen Gulf, 
and more northerly areas (Davis and Evans, 1982; Harwood et al., 1996; 
Richard et al., 2001). Belugas are rarely seen in the central Alaskan 
Beaufort Sea during the early summer. During late summer and autumn, 
most belugas migrate westward far offshore near the pack ice (Frost et 
al., 1988; Hazard, 1988; Clarke et al., 1993; Miller et al., 1999), 
with the main fall migration corridor approximately 160 km (100 mi) or 
more north of the coast. Therefore, most belugas migrate well offshore 
away from the proposed project area, although there is a small 
possibility that they could occur near the project area in small 
numbers. MMOs will be monitoring the exclusion zones for all marine 
mammals. Therefore, in the event that belugas are sighted in the 
project area, the appropriate mitigation measures (described later in 
this document) will be implemented. Additionally, as PGS does not 
intend to use ice-breakers during its seismic survey, statements 
regarding beluga reactions to ice-breaker noise are not relevant to 
this activity.
    Comment 22: The NSB DWM points out that while ringed seals may be 
the most common marine mammal species in the area, since the seismic 
shoot is near a spotted seal haulout in the Colville River Delta, PGS 
should expect to encounter and expose spotted seals to seismic sounds. 
Additional information is needed about impacts from seismic activities 
on spotted seals, including impacts to seals at haulouts.
    Response: Both the application and proposed IHA notice analyze the 
distribution, density, and potential impacts to spotted seals. NMFS 
estimates that 178 spotted seals may be exposed to sound levels of 160 
dB (rms) or greater and thereby possibly taken as a result of PGS' 
seismic survey. Impacts to spotted seals are not expected to be all 
that different than those to the other ice seals in the area. While 
there may be some behavioral disturbance, for reasons stated earlier in 
this document, TTS and PTS are not expected for spotted seals or any 
other marine mammal species. Additionally, if the animals are hauled 
out during seismic shooting, then they would not be exposed to 
underwater noise.
    Comment 23: The NSB is concerned about the potential impacts of 
PGS' seismic survey to the food sources of marine mammals. Part of the 
survey occurs in productive nearshore waters. Additional information is 
needed about impacts from seismic surveys to marine mammal prey and the 
resulting impacts to the marine mammals themselves.
    Response: PGS has modified the project timeline to address concerns 
from local subsistence users regarding impacts to fish. PGS has agreed 
not to begin work inside the barrier islands prior to August 5. 
Additionally, NMFS does not expect the proposed action to have a 
substantial impact on biodiversity or ecosystem function within the 
affected area. The potential for the PGS activity to affect ecosystem 
features and biodiversity components, including fish and invertebrates, 
is fully analyzed in the 2006 PEA and incorporated by reference into 
the 2008 SEA. NMFS' evaluation indicates that any direct, indirect, or 
cumulative effects of the action would not result in a substantial 
impact on biodiversity or ecosystem function. In particular, the 
potential for effects to these resources are considered here with 
regard to the potential effects on diversity or functions that may 
serve as essential components of marine mammal habitat. Most effects 
are considered to be short-term and unlikely to affect normal ecosystem 
function or predator/prey relationships; therefore, NMFS believes that 
there will not be a substantial impact on marine life biodiversity or 
on the normal function of the nearshore or offshore Beaufort Sea 
ecosystems.
    During the seismic survey, only a small fraction of the available 
habitat would be ensonified at any given time. Disturbance to fish 
species would be short-term, and fish would return to their pre-
disturbance behavior once the seismic activity in a specific area 
ceases. Thus, the proposed survey would have little, if any, impact on 
the ability of marine mammals to feed in the area where seismic work is 
conducted.
    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). A react