Taking and Importing of Marine Mammals; Offshore Seismic Activities in the Beaufort Sea

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[I.D. 040799A]

Taking and Importing of Marine Mammals; Offshore Seismic

Activities in the Beaufort Sea

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and

Atmospheric Administration (NOAA), Commerce.

ACTION: Notice of issuance of an incidental harassment authorization.

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SUMMARY: In accordance with provisions of the Marine Mammal Protection

Act (MMPA) as amended, notification is hereby given that an Incidental

Harassment Authorization (IHA) to take small numbers of bowhead whales

and other marine mammals by harassment incidental to conducting seismic

surveys in the Western Beaufort Sea in state and Federal waters has

been issued to Western Geophysical/Western Atlas International of

Houston, Texas (Western Geophysical).

DATES: Effective from July 20, 1999, until November 1, 1999, unless

extended.

ADDRESSES: The application, authorization, monitoring plan,

environmental assessment (EA), and a list of references used in this

document are available by writing to Donna Wieting, Chief, Marine

Mammal Conservation Division, Office of Protected Resources, NMFS, 1315

East-West Highway, Silver Spring, MD 20910-3225, or by telephoning one

of the contacts listed here.

FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead, NMFS, (301)

713-2055, Brad Smith, NMFS, (907) 271-5006.

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 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.

Permission may be granted if NMFS finds that the taking will have a

negligible impact on the species or stock(s) and will not have an

unmitigable adverse impact on the availability of the species or

stock(s) for subsistence uses and if the permissible methods of taking

and requirements pertaining to the monitoring and reporting of such

taking are set forth.

On April 10, 1996 (61 FR 15884), NMFS published an interim rule

establishing, among other things, procedures for issuing incidental

harassment authorizations under section 101(a)(5)(D) of the MMPA in

Arctic waters. For additional information on the procedures to be

followed for this authorization, please refer to that document.

Summary of Request

On March 24, 1999, NMFS received an application from Western

Geophysical requesting an authorization for the harassment of small

numbers of several species of marine mammals incidental to conducting

seismic surveys during the open water season in the Beaufort Sea

between western Camden Bay and Harrison Bay off northern Alaska.

Weather permitting, the survey is expected to take place between

approximately July 1 and mid- to late-October, 1999. However, only a

small portion of the area between western Camden Bay and Harrison Bay

will be surveyed this year. A detailed description of the work proposed

for 1999 is contained in the application (Western Geophysical, 1999)

and is available upon request (see ADDRESSES).

Disturbance by seismic noise is the principal means of taking by

this activity. Support vessels and aircraft will provide a potential

secondary source of noise. The physical presence of vessels and

aircraft could also lead to non-acoustic effects on marine mammals

involving visual or other cues.

Seismic surveys are used to obtain data about geological formations

several thousands of feet deep. The proposed seismic operation is an

ocean bottom cable (OBC) survey. For this activity, OBC surveys involve

dropping cables from a ship to the ocean bottom, forming a patch

consisting of 4 parallel cables 8.9 kilometers (km) (4.8 nautical miles

(nm)) long, separated by approximately 600 meters (m) (1,968 feet (ft))

from each other. Hydrophones and geophones, attached to the cables, are

used to detect seismic energy reflected back from underground rock

strata. The source of this energy is a submerged acoustic source,

called a seismic airgun array, that releases compressed air into the

water, creating an acoustical energy pulse that is directed downward

toward the seabed. The source level planned for this project - a

maximum of 247 dB re 1 Pa-m or 22.3 bar-meters (zero to peak),

or a maximum of 252 dB re 1 Pa-m or 39 bar-meters (peak-to-

peak) - will be from an airgun array with a air discharge volume of

1,210 in3. This compares to the 1,500 in3 array

used on Western Geophysical's primary source vessel in 1998 and will be

the only airgun array used by Western Geophysical in the Beaufort Sea

this year.

It is anticipated that 34 seismic lines will be run for each patch,

covering an area 5.0 km by 15.7 km (2.7 nm by 8.1 nm), centered over

the patch. Source lines for one patch will overlap with those for

adjacent patches.

After sufficient data have been recorded to allow accurate mapping

of the rock strata, the cables are lifted onto the deck of a cable-

retrieval vessel, moved to a new location (ranging from several hundred

to a few thousand feet away), and placed onto the seabed again. For a

more detailed description of the seismic operation, please refer to the

1999 application from Western Geophysical.

Depending upon ambient noise conditions and the sensitivity of the

receptor, underwater sounds produced by open water seismic operations

may be detectable a substantial distance away from the activity. Any

sound that is detectable is (at least in theory) capable of eliciting a

disturbance reaction by a marine mammal or of masking a signal of

comparable frequency (Western Geophysical, 1999). An incidental

harassment take is presumed to occur when marine mammals in the

vicinity of the seismic source, the seismic vessel, other vessels, or

aircraft react to the generated sounds or to visual cues.

Seismic pulses are known to cause strong avoidance reactions by

many of the bowhead whales occurring within a distance of several

kilometers and may sometimes cause avoidance or other changes in

bowhead behavior at considerably greater distances (Richardson et al.,

1995; Rexford, 1996; MMS, 1997). It is also possible that seismic

pulses may disturb some other marine mammal species occurring in the

area.

Although some limited masking of low-frequency sounds (e.g., whale

calls) is a possibility, the intermittent nature of seismic source

pulses (Parms @ 1 m). It is possible that, when

additional data are available and analyzed, it may be demonstrated that

isolated bowheads avoid seismic vessels at distance beyond 20 km (10.8

nm). Also, the ``skittish'' behavior may be related to the observed

subtle changes in the behavior of bowheads exposed to seismic pulses

from distant seismic vessels (Richardson et al., 1986).

Gray Whales

The reactions of gray whales to seismic pulses are similar to those

of bowheads, but apparently are limited to animals exposed to higher

levels of seismic pulses. Migrating gray whales along the California

coast were noted to slow their speed of swimming, turn away from

seismic noise sources, and increase their respiration rates. Malme et

al. (1983, 1984, 1988) concluded that approximately 50 percent showed

avoidance when the average received pulse level was 170 dB (re 1

Pa). By some behavioral measures, clear effects were evident

at average pulse levels of 160+dB; less consistent results were

suspected at levels of 140-160 dB. Recent research on migrating gray

whales showed responses similar to those observed in the earlier

research when the source was moored in the migration corridor 2 km (1.1

nm) from shore. However, when the source was placed offshore (4 km (2.2

nm) from shore) of the migration corridor, the avoidance response was

not evident on track plots (Tyack and Clark, 1998).

Beluga

The beluga is the only species of toothed whale (Odontoceti)

expected to be encountered in the Beaufort Sea. Because the beluga

hearing threshold at frequencies below 100 Hz (where most of the energy

from airgun arrays is concentrated) is poor (125 dB re 1 Pa)

or more depending upon frequency (Johnson et al., 1989; Richardson et

al., 1991, 1995), beluga are not predicted to be strongly influenced by

seismic noise. However, because of the high source levels of seismic

pulses, airgun sounds sometimes may be audible to beluga at distances

of 100 km (54 nm)(Richardson and Wursig, 1997). The reaction distance

for beluga, although presently unknown, is expected to be less than

that for bowheads, given the presumed poorer sensitivity of belugas

than that of bowheads for low-frequency sounds (Western Geophysical,

1999).

Ringed, Largha and Bearded Seals

No detailed studies of reactions by seals to noise from open water

seismic exploration have been published (Richardson et al., 1995).

However, there are some data on the reactions of seals to various types

of impulsive sounds (LGL and Greeneridge, 1997, 1998, 1999a; J. Parsons

as quoted in Greene, et al. 1985; Anon., 1975; Mate and Harvey, 1985).

These studies indicate that ice seals typically either tolerate or

habituate to seismic noise produced from open water sources.

Underwater audiograms have been obtained using behavioral methods

for three species of phocinid seals: ringed, harbor, and harp seals

(Pagophilus groenlandicus). These audiograms were reviewed in

Richardson et al. (1995) and Kastak and Schusterman (1998). Below 30-50

kHz, the hearing threshold of phocinids is essentially flat down to at

least 1 kHz and ranges between 60 and 85 dB (re 1 Pa @ 1 m).

There are few data on hearing sensitivity of phocinid seals below 1

kHz. NMFS considers harbor seals to have a hearing threshold of 70-85

dB at 1 kHz (60 FR 53753, October 17, 1995), and recent measurements

for a harbor seal indicate that, below 1 kHz, its thresholds

deteriorate gradually to 96 dB (re 1 Pa @ 1 m) at 100 Hz

(Kastak and Schusterman, 1998).

Recent studies have provided some data are available on the

reactions of seals to various types of impulsive sounds (see LGL and

Greeneridge, 1997,

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1998, 1999a; Thompson et al. 1998). These references indicate that it

is unlikely that pinnipeds would be harassed or injured by low

frequency sounds from a seismic source unless they were within

relatively close proximity of the seismic array. For permanent injury,

pinnipeds would likely need to remain in the high-noise field for

extended periods of time. Existing evidence also suggests that, while

seals may be capable of hearing sounds from seismic arrays, they appear

to tolerate intense pulsatile sounds without known effect once they

learn that there is no danger associated with the noise (see, for

example, NMFS/Washington Department of Wildlife, 1995). In addition,

they will apparently not abandon feeding or breeding areas due to

exposure to these noise sources (Richardson et al., 1991) and may

habituate to certain noises over time. Since seismic work is fairly

common in Beaufort Sea waters, pinnipeds have been previously exposed

to seismic noise and may not react to it after initial exposure.

For a discussion on the anticipated effects of ships, boats, and

aircraft, on marine mammals and their food sources, please refer to the

application (Western Geophysical, 1999). Information on these effects

is incorporated in this document by citation.

Numbers of Marine Mammals Expected to be Taken

Western Geophysical estimates that the following numbers of marine

mammals may be subject to Level B harassment, as defined in 50 CFR

216.3:

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

Harassment Takes in 1999

Species Population -------------------------

Size Possible Probable

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

Bowhead 9,900

160 dB criterion - 1,000 200,000 10 300,000 50 o10'N,

144oW (Kaleak, 1996). That site is approximately 40 km (21.6

nm) east of the closest part of Western Geophysical's planned seismic

exploration area for 1999 (Western Geophysical, 1999).

Whalers from the village of Barrow search for bowhead whales much

further from the planned seismic area, >200 km (>108 nm) west (Western

Geophysical, 1999).

The location of the proposed seismic activity is south of the

center of the westward migration route of bowhead whales, but there is

some overlap. Seismic monitoring results from 1996-1998 indicate that

most bowheads avoid the area within about 20 km (11 nm) around the

array when it is operating. In addition, bowheads may be able to hear

the sounds emitted by the seismic array out to a distance of 50 km (27

nm) or more, depending on the ambient noise level and the efficiency of

sound propagation along the path between the seismic vessel and the

whale (Miller et al., 1997). Western Geophysical (1999) believes it is

unlikely that changes in migration route will occur at distances

greater than 25 km (13 nm) from an array of maximum volume of 1,210

in3 operating in water less than 30 m (100 ft) deep.

However, subtle changes in behavior might occur out to longer

distances. Inupiat whalers believe that bowheads begin to divert from

their normal migration path more than 35 miles (56 km) away (MMS,

1997).

It is recognized that it is difficult to determine the maximum

distance at which reactions occur (Moore and Clark, 1992). As a result,

Western Geophysical are participating in a C&AA with the whalers to

reduce any potential interference with the hunt. Also, it is believed

that the monitoring plan proposed by Western Geophysical (1999; also

see LGL Ltd. and Greeneridge Sciences Inc, 1999b) will provide

information that will help resolve uncertainties about the effects of

seismic exploration on the accessibility of bowheads to hunters.

Many Nuiqsut hunters hunt seals intermittently year-round. However,

during recent years, most seal hunting

[[Page 41387]]

has been during the early summer in open water. In summer, boat crews

hunt ringed, spotted and bearded seals. The most important sealing area

for Nuiqsut hunters is off the Colville delta, extending as far west as

Fish Creek and as far east as Pingok Island. This area overlaps with

the westernmost portion of the planned seismic area. In this area,

during summer, sealing occurs by boat when hunters apparently

concentrate on bearded seals. However, these subsistence hunters have

not perceived any interference from recent open-water seismic

activities in the Alaskan Beaufort Sea. Therefore, because Western

Geophysical is proposing similar mitigation and consultation procedures

this year, it is unlikely that seismic activities would have more than

a negligible impact on Nuiqsut seal hunting.

Comments and Responses

A notice of receipt of the application and proposed authorization

was published on May 28, 1999 (64 FR 28992), and a 30-day public

comment period was provided on the application and proposed

authorization. During the comment period, comments regarding this

application were received from the Marine Mammal Commission (MMC), LGL

Ltd. environmental research associates on behalf of the applicant, and

Greenpeace Alaska (Greenpeace).

MMPA Concerns

Comment 1: LGL Ltd provided information updating and correcting the

Federal Register notice that Western has no intention to use an array

larger than 1,210 in3 during 1999.

Response: Thank you for providing this information.

Comment 2: LGL Ltd questioned the statement in the Federal

Register document that the proposed seismic activity occurs in waters

generally too shallow and distant from the edge of the pack ice for

most marine mammals, and that this statement is not consistent with the

IHA Application and the EA. LGL notes that 5 of the 6 marine mammal

species requested for taking occur within the seismic area; only the

beluga remains (with a few exceptions) far offshore near the ice edge.

Response: NMFS agrees.

Comment 3: Greenpeace believes that NMFS and Western Geophysical

have failed to provide the evidence necessary to justify issuance of

the IHA by relying on outdated, incomplete and inaccurate information

on the zone of influence of seismic operations on bowhead whales.

Response: To make a determination of negligible impact on marine

mammal stocks or a finding of not having an unmitigable adverse impact

on subsistence uses of marine mammals, NMFS relies on the best

scientific information available. The latest scientific information has

been obtained through a 3-year program of data collection and analysis,

including aerial surveys and acoustic monitoring. Greenpeace does not

identify any additional sources of information not already considered

by NMFS or Western Geophysical. Western Geophysical's IHA application

and the notice of proposed authorization note that, in addition to the

known responses of bowhead whales out to a distance of several

kilometers, less conspicuous and/or less frequent effects may extend to

greater distances. The draft final monitoring report describing the

1996 through 1998 monitoring results (Richardson [ed.], 1999) shows

that (1) 1996, 1997 and 1998 seismic programs did not greatly influence

the position of the overall migration corridor; (2) the aerial surveys

showed avoidance of the area within 20 km (12 mi) of seismic

operations, plus partial avoidance of the area 20-30 km (12-19 mi)

away, and (3) based on 1998 research, there is no evidence that bowhead

disturbance extended 37 km (23 mi) offshore of the northern edge of the

seismic exploration area. For additional information on the estimated

zones that seismic airgun noise may have an effect on bowhead whales,

please refer to the proposed authorization notice mentioned in this

document.

Scientists, at least, recognize that it is difficult (for to

determine the maximum distance at which disturbance and avoidance

reactions may have an adverse impact on subsistence needs (Moore and

Clark, 1992). Inupiat whalers, on the other hand, believe that whales

exhibit avoidance reactions as far as 30 miles (48 km) away (MMS,

1997). As a result, Western Geophysical has developed a C&AA with the

whalers to reduce any potential interference with the hunt.

Also, it is believed that the monitoring plan proposed by Western

Geophysical (LGL Ltd., LGL Alaska Research Associates, and Greeneridge,

1999), revised on the basis of comments received during this public

comment period and at the Peer-Review Workshop, will provide

information that will help resolve uncertainties about the effects of

seismic exploration on the bowhead whales and the accessibility of

bowheads to hunters.

Comment 4: Greenpeace believes the scientific evidence remains

inadequate to determine whether hearing or behavior of marine mammals

may be damaged temporarily or permanently by seismic operations. This

makes it impossible to put adequate mitigation measures into place when

there is inadequate knowledge about the impacts of seismic operations

on cetaceans' hearing and behavior.

Response: The impact of airguns on bowhead hearing and behavior has

been addressed in several documents, including Western Geophysical's

application, the supporting EA, and in LGL Ltd and Greeneridge Sciences

(1998) and most recently in LGL Ltd, LGL Alaska Research Associates,

and Greeneridge Sciences (1999). Without an ability to collect

empirical information on physical impacts from airguns on large marine

mammals, scientists must rely on surrogate species and make

conservative assumptions based upon findings for those species. For

bowhead and beluga whales, NMFS and Western Geophysical use the best

scientific information available which indicates that a safety zone set

at the 180 dB (re 1 Pa) isopleth will protect bowhead and

beluga whales from potential serious injury. Furthermore, the avoidance

reactions by bowheads and the offshore migration corridor of belugas

minimize the number of bowheads and belugas entering or approaching the

180 dB zone. Only one bowhead and no belugas have been seen in that

zone during the 1996, 1997, and 1998 monitoring projects (Richardson et

al., 1999). Because there are potential behavioral effects on bowhead

whales by seismic activities, an IHA is warranted. Under the IHA, NMFS

will require Western Geophysical to incorporate mitigation and

monitoring measures approved by the 1999 Peer Review Workshop

participants to reduce potential impacts on whales and seals to the

lowest level practicable.

Comment 5: Greenpeace notes that NMFS fails to place restrictions

on seismic operations during times of limited or zero visibility.

Response: Observers monitor the safety zones and zones of potential

harassment around the seismic source whenever visibility permits, and

the source is either on or within 30 minutes of powering up. This year

observers will be aided by high-intensity lighting for monitoring the

safety zone at night. Assessments of takes by harassment will be made

based upon the percentage of time spent observing in relation to the

total time for seismic operations. Because: (1) relatively few marine

mammals are expected in the area during the time of the survey, (2) the

vessels are underway at low speeds while conducting seismic surveys,

theoretically allowing animals sufficient time to move away from any

[[Page 41388]]

annoyances, and (3) documented observations indicate that bowhead

whales avoid active seismic survey areas, few marine mammals, and no

bowheads, are expected to approach the vessel. Therefore, terminating

surveys at night and during inclement weather is not warranted, in part

since to do so could extend the seismic season into the peak bowhead

migration period resulting in an increased level of harassment of that

species.

Comment 6: Greenpeace states that the issuance of an IHA will

result in significant and unmitigable impacts to subsistence

communities and the Arctic marine environment.

Response: Section 101(a)(5)(D)(i)(II) of the MMPA requires NMFS to

ensure that any taking will not have an unmitigable adverse impact on

the availability of the species or stock(s) for subsistence uses. NMFS

relies on two factors in determining if there will be an unmitigable

adverse impact on subsistence uses: First, the impact resulting from

the specified activity must be likely to reduce the availability of the

species to a level insufficient for a harvest to meet subsistence needs

by (1) causing the marine mammals to abandon or avoid hunting areas,

(2) directly displacing subsistence users, or (3) placing physical

barriers between the marine mammals and subsistence hunters. Second, it

must be an impact that cannot be sufficiently mitigated by other

measures to increase the availability of marine mammals to allow

subsistence needs to be met (50 CFR 216.103). This standard of

determining impact does not require the elimination of adverse impacts,

but it does require mitigation sufficient to meet subsistence

requirements. However, the MMPA also requires that, where applicable,

the measures will ensure the least practicable impact on the

availability of marine mammals for taking for subsistence uses. In

previous years, these conditions were met through the AEWC/oil

industry's C&AA which required seismic operations to move west of Cross

Island no later than September 1 or when whalers commenced the bowhead

hunting season, whichever was earlier. A signed C&AA allows NMFS to

conclude that there will not be an unmitigable adverse impact on the

subsistence needs of the Arctic Slope whalers this year due to seismic

activities.

Comment 7: LGL Limited notes that the mitigation section of the

Federal Register document does not mention that Western Geophysical

plans to participate in a C&AA with the whalers in order to avoid

interference with the autumn bowhead hunt. While the C&AA is mentioned

in the previous section (regarding impacts on subsistence uses),

Western Geophysical and LGL Ltd view the C&AA as one of the primary

mitigation measures, as it addresses the requirement to identify

measures to ensure the ``least practicable adverse impact on

...availability for subsistence uses.''

Response: Thank you for the comment.

Comment 8: Greenpeace contends that Western Geophysical's proposed

marine mammal monitoring program fails to adequately monitor the impact

of seismic operations on marine mammals.

Response: NMFS disagrees. Section 101(a)(5)(D)(ii)(II) of the MMPA

requires authorizations issued under this section to prescribe, where

applicable, requirements pertaining to the monitoring and reporting of

such taking by harassment, including requirements for independent peer

review of proposed monitoring plans or other research proposals where

the proposed activity may affect the availability of a species or stock

for taking for subsistence purposes.

Western Geophysical's proposed monitoring plan for 1999 and the

results from Western Geophysical's 1998 Beaufort Sea research were the

subject of a scientific peer-review workshop held in Seattle, WA, on

June 30 and July 1, 1999. As a result of that workshop, Western

Geophysical is amending its monitoring plan and will submit that plan

to NMFS for approval prior to commencement of the bowhead season.

Modifications to the original plan for monitoring during the bowhead

season (if seismic surveys are continuing at that time) include (1) an

extension of the aerial survey grid by an extra 15 km (8 nm) east and

west to approximately 65 km (35 nm) westward and 65 km eastward of the

seismic survey; this will address the issues (a) how far west of the

seismic area do bowhead whales remain farther offshore than usual if

bowheads are displaced offshore by seismic and (b) where the bowhead

whale deflection from the migration track due to seismic noise begins;

(2) an increase in the number of aerial survey track lines from 14 to

18; and (3) commencing the aerial surveys on September 1, rather than

September 4; and (4) additional autonomous seafloor acoustic recorders

offshore from the area of seismic operations.

Comment 9: The MMC recommends that the peer-review group

established to review the proposed monitoring and mitigation programs

be asked to consider the following questions: (1) Whether continuation

of the marine mammal observations in association with seismic surveys

in the nearshore waters of the Alaska Beaufort Sea beyond 1999 is

likely to produce significant new information on either the short- or

long-term effects of seismic surveys on marine mammals that occur in

the area, (2) whether the types of site-specific monitoring programs

conducted to date are sufficient to verify that seismic surveys and

related activities have negligible effects on the distributions, sizes,

and populations, and (3) if the answer to either issue is no, how

should the monitoring requirements be revised to better meet the intent

and provisions of the MMPA?

Response: NMFS believes that at a minimum, shipboard monitoring of

the safety zone must continue to implement mitigation measures to

protect marine mammals from potential serious injury. The Scientific

Peer Review Workshop participants concluded that the current research

and monitoring proposed here by Western Geophysical and by BPX for oil

development at Northstar (see 64 FR 9965, March 1, 1999), coupled with

existing projects to monitor bowhead population abundance (trends in

abundance) should provide information necessary to determine overall

cumulative impacts on bowhead whales. Existing projects include those

by the North Slope Borough (spring bowhead census), the MMS autumn

aerial survey, and the MMS-funded photo-identification of bowhead

whales being conducted as part of an on-going (1998-2000) bowhead

feeding study. Provided trends in bowhead abundance continue to be

positive, NMFS presumes industrial development on the North Slope is

not adversely affecting the bowhead population. Similar work is

underway for ringed seals.

Comment 10: Greenpeace believes that NMFS ignores cumulative

impacts from oil exploration and development in the Arctic on

subsistence communities, the bowhead whale, other marine mammals, and

the Arctic marine environment.

Response: Information on the cumulative impacts on the marine

environment from Beaufort Sea oil and gas leasing and development

activities, including seismic, in the area under discussion has been

addressed previously in several environmental impact statements (EIS)

prepared by the Minerals Management Service (MMS) (Final EISs for Lease

Sale 124 and 144 completed in 1990 and 1996). More recently, cumulative

impacts from oil exploration and development were extensively discussed

and evaluated in the U.S. Army Corps of Engineer's Final Environmental

Impact Statement (FEIS) on the Northstar Oil Development

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Project (Corps, 1999). NMFS was a cooperating agency under the National

Environmental Policy Act (NEPA) in the preparation of that document.

Additional discussion on cumulative impacts from seismic activities in

conjunction with offshore oil and gas exploration and development can

be found in the EA prepared for this action (NMFS, 1999). NMFS notes

that because the Northstar Project construction has been delayed until

after the 1999 open water season, other than commercial barge traffic,

there are no identified activities that might cause a cumulative impact

on the whales, seals or subsistence needs of the North Slope this

season.

Comment 11: Noting that the activity for which an IHA

authorization is requested is part of an effort likely to be continued

in subsequent years and to eventually lead to drilling and other

activities associated with oil and gas exploration and production, the

MMC questions whether there is sufficient basis for concluding that

this year's activities, coupled with past and possible future

activities will not have a non-negligible cumulative effects on any of

the potentially affected marine mammal species or their availability to

Alaska Natives for subsistence uses. As a result, the MMC recommends

that NMFS, if it has not already done so, assess whether the monitoring

required as a condition of this and possible future IHAs will be

adequate to detect possible non-negligible cumulative effects and, if

not, what needs to be done to ensure that any such effects will be

detected before they reach significant levels and could be

irreversible.

Response: Please see response to comment 9.

Comment 12: Greenpeace noted that the results of Western

Geophysical's 1998 marine mammal monitoring program are not available

for review along with its 1999 IHA application. The results of the 1998

monitoring program should be available for public review prior to the

close of the public comment period.

Response: The preliminary results of the 1998 monitoring program

are contained in the 90-day report, which was issued in January 1999,

and in the IHA application. The draft final report for 1998 was due on

April 30, 1999. Because the draft final report was expanded to contain

an analysis of several previous years' data, the availability of this

report was delayed until late May, when it was reviewed by NMFS

scientists and participants at the peer review workshop. While

monitoring reports are available to the public for review, there is no

requirement for these documents to be made available for formal public

review and comment. Reviewers are encouraged to rely on the 90-day

report and reports from prior years if they wish to analyze the

previous years' data. As noted by Greenpeace in their letter, the 1996

and 1997 monitoring reports have been reviewed by them.

Endangered Species Act (ESA) Concerns

Comment 13: Without clarification, Greenpeace believes that

issuance of the IHA would violate the ESA.

Response: NMFS disagrees, noting that the issuance of an IHA to

Western Geophysical triggers section 7 of the ESA, as the issuance of

the IHA is a Federal action (please refer to the section titled ESA

later in this document). However, the major Federal agency for offshore

oil and gas lease activities is the MMS. Consultation under section 7

for lease sale 144 was concluded on November 16, 1995 with a finding

that the action was not likely to jeopardize the continued existence of

listed species under the jurisdiction of NMFS. This finding is

consistent with the conclusions and recommendations contained within

the Arctic Region Biological Opinion issued to MMS under section 7 of

the ESA by NMFS on November 23, 1988.

Reinitiation of formal consultation under section 7 is warranted

only when there is new scientific information that has the potential to

call into question the scientific and commercial data used in the

previous biological opinion. At this time, NMFS does not consider the

recent findings on impacts to listed marine species from the

disturbance from seismic surveys sufficient to reinitiate consultation.

NEPA Concerns

Comment 14: Greenpeace believes that the EA fails to adequately

analyze the full scope and cumulative impacts of current and proposed

offshore exploration and development activities in the Beaufort Sea.

Greenpeace maintains that the impacts from seismic operations cannot be

assessed separately from cumulative impacts from offshore exploratory

drilling, development and transportation activities that may follow or

are already occurring. This includes the impact of global warming on

the Arctic environment.

Response: Please see response to comment 10.

Mitigation

This year, Western Geophysical will reduce its airgun array from

the 1,500 in3 used in 1998 to 1,210 in3 and

investigate whether it is practical to modify the design to reduce

horizontal propagation of sound. These changes are expected to result

in lower received levels and, therefore, smaller safety ranges and

reduced takes by harassment than in 1998. However, because the 1,210

in3 array is a subset (with some minor variations) of the

1,500 in3 array (with 4 guns not firing), NMFS is limiting

the IHA authorization for a taking by harassment to no more than 12

airguns totaling 1,210 in3 during the 1999 open water

seismic survey. Vessel-based observers will monitor marine mammal

presence in the vicinity of the seismic array throughout the seismic

program. To avoid the potential for serious injury to marine mammals,

Western Geophysical will power down the seismic source if pinnipeds are

sighted within the area delineated by the 190 dB isopleth or 240 m

(787.4 ft) from the array operating at 5 m (16.4 ft) depth or 80 m

(262.5 ft) from the array operating at 2 m (6.6 ft) depth.

Western Geophysical will power down the seismic source if bowhead,

gray, or beluga whales are sighted within the area delineated by the

180 dB isopleth or within 750 m (2,460.6 ft) of the array operating at

5 m ( 16.4 ft) depth or 360 m (1,181.1 ft) of the array operating at 2

m (6.6 ft) depth. However, because these safety zones were based on

measurements near the 1998 seismic array plus theoretical adjustments

for the smaller array size in 1999, within the first 10 days of

Beaufort Sea operations in 1999, Western Geophysical will measure and

analyze the sounds from Western's 1999 array operating at both 5 m

(16.4 ft) and 2 m (6.6 ft) depths. This information will be provided to

NMFS, along with the contractor's recommendation as to whether any

adjustments in the safety radii are needed to meet the 190 and 180

dBrms shutdown criteria.

In addition, Western Geophysical will ramp-up the seismic source to

operating levels at a rate no greater than 6 dB/min anytime the array

has not been firing for 1-2 minutes (depending upon vessel speed).

Ramp-up will begin with an air volume discharge not exceeding 80

in3 with additional guns added at intervals appropriate to

limit the rate of increase to 6 dB/min.

Monitoring

As part of its application, Western Geophysical provided a

monitoring plan for assessing impacts to marine mammals from seismic

surveys in the Beaufort Sea. This monitoring plan is described in

Western Geophysical (1999) and in LGL Ltd., LGL Alaska Research

Associates, and Greeneridge Sciences (1999). This monitoring plan

[[Page 41390]]

has been peer-reviewed by NMFS, AEWC and industry scientists and others

at a workshop held in Seattle, WA on June 30 and July 1, 1999.

Suggested modifications to the monitoring plan as a result of the

workshop (most notably those summarized previously in the response to

comment 8) will need to be incorporated into the Plan prior to formal

acceptance by NMFS. During the 1999 open-water season, Western

Geophysical will conduct the following:

Vessel-based Visual Monitoring

One or two biologist-observers aboard the seismic vessel will

search for and observe marine mammals whenever seismic operations are

in progress, and for at least 30 minutes prior to planned start of

shooting. These observers will scan the area immediately around the

vessels with reticle binoculars during the daytime supplemented with

night-vision equipment during the night (prior to mid-August, there are

no hours of darkness). In addition, Western Geophysical will experiment

with illumination of the safety zone with high-intensity lighting.

A total of four observers (three trained biologists and one Inupiat

observer/communicator) will be based aboard the seismic vessel. Use of

four observers is an increase over 1998 and will allow two observers to

be on duty simultaneously for up to 50 percent of the active airgun

hours. Use of two observers will increase the probability of detecting

marine mammals and two observers will be required to be on duty

whenever the seismic array is ramped up. Individual watches will

normally be limited to no more than 4 consecutive hours.

When mammals are detected within or about to enter the safety zone

designated to prevent injury to the animals (see Mitigation), the

geophysical crew leader will be notified so that shutdown procedures

can be implemented immediately.

Aerial Surveys

If the seismic program continues after August 31, Western

Geophysical will conduct daily aerial surveys, weather permitting, from

September 1, 1999, for a period of 13-14 days, or, if seismic work ends

before September 13, until one day after seismic work ends. The primary

objective will be to document the occurrence, distribution, and

movements of bowhead and (secondarily) beluga and gray whales in and

near the area where they might be affected by the seismic pulses. These

observations will be used to estimate the level of harassment takes and

to assess the possibility that seismic operations affect the

accessibility of bowhead whales for subsistence hunting. Pinnipeds will

be recorded when seen. Aerial surveys will be at an altitude of 300 m

(1,000 ft) above sea level. Western Geophysical will fly at 457 m (1500

ft) altitude over areas where whaling is occurring on that date to

avoid direct overflights of whaleboats and Cross Island, where whalers

from Nuiqsut are based during their fall whale hunt.

The daily aerial surveys are proposed to cover a grid of 18 north-

south lines spaced 8 km (4.3 nm) apart and will extend seaward to about

the 100 m (328 ft) depth contour (typically about 65 km (35 nm)

offshore. This grid will extend from about 65 km (35 nm) east to 65 km

(35 nm) west of the area in which seismic operations are underway on

that date. This design will provide extended coverage to the west to

determine the westward extent of the offshore displacement of whales by

seismic. In 1999, the additional ``intensive'' grid survey will not be

conducted as in previous years.

Detailed information on the survey program can be found in Western

Geophysical (1999) and in LGL Ltd., LGL Alaska Research Associates, and

Greeneridge Sciences Inc. (1999), which are incorporated in this

document by citation.

Acoustical Measurements

The acoustic measurement program for 1999 is designed to continue

the acoustic work conducted in 1996 through 1998 (see LGL and

Greeneridge Sciences Inc., 1997, 1998, 1999). The acoustic measurement

program is planned to include (1) vessel-based acoustic measurements,

(2) OBC-based acoustic measurements, and, if seismic operations

continue into September, (3) use of air-dropped sonobuoys and (4)

bottom-mounted acoustical recorders.

(1) A vessel-based acoustical measurement program will be conducted

for a few days early in the seismic program. The objectives of this

survey will be as follows: (a) to measure the levels and other

characteristics of the horizontally propagating seismic survey sounds

from the type of airgun array to be used in 1999 as a function of

distance and aspect relative to the seismic source vessel and in

relation to the operating depth of the airguns, and (b) to measure the

levels and frequency composition of the vessel sounds emitted by

vessels used regularly during the 1999 program in those cases when

these vessels have not previously been measured adequately.

(2) Western Geophysical and Greeneridge Sciences will use recorded

signals from Western's OBC system to help document horizontal

propagation of the seismic survey pulses.

(3) Sonobuoys will be dropped and monitored from bowhead survey

aircraft during September 1 through 13, 1999 (if the seismic operations

are continuing at that time). Sonobuoys will provide data on

characteristics of seismic pulses (and signal-to-ambient ratios) at

offshore locations, including some of those places where bowhead whales

are observed.

(4) Autonomous seafloor acoustic recorders will be placed on the

sea bottom at two locations offshore of the seismic operation area, and

at one location about 40 km (25 mi) to the east, to record low-

frequency sounds nearly continuously for up to 3 weeks at a time during

September (if seismic operations are continuing at that time).

Information includes characteristics of the seismic pulses, ambient

noise, and bowhead calls.

For a more detailed description of planned monitoring activities,

please refer to the application and supporting document (Western

Geophysical, 1999; LGL Ltd., LGL Alaska Research Associates, and

Greeneridge Sciences, 1999).

Estimates of Marine Mammal Take

Estimates of takes by harassment will be made through vessel and,

if seismic operations continue into September, aerial surveys. Western

Geophysical will estimate the number of (a) marine mammals observed

within the area ensonified strongly by the seismic vessel; (b) marine

mammals observed showing apparent reactions to seismic pulses (e.g.,

heading away from the seismic vessel in an atypical direction); (c)

marine mammals subject to take by type (a) or (b) when no monitoring

observations were possible; and (d) bowheads displaced seaward from the

main migration corridor.

Reporting

Western Geophysical will provide an initial report on 1999

activities to NMFS within 90 days of the completion of the seismic

program. This report will provide dates and locations of seismic

operations, details of marine mammal sightings, estimates of the amount

and nature of all takes by harassment, and any apparent effects on

accessibility of marine mammals to subsistence users.

A final technical report will be provided by Western Geophysical

within 20 working days of receipt of the document from the contractor,

but no later than April 30, 2000. The final

[[Page 41391]]

technical report will contain a description of the methods, results,

and interpretation of all monitoring tasks. This report will be subject

to review and comment by NMFS. Any recommendations made by NMFS will

need to be addressed in the final report prior to formal acceptance by

NMFS.

Consultation

Under section 7 of the ESA, NMFS has completed consultation on the

issuance of this authorization.

NEPA

In conjunction with the 1996 notice of proposed authorization (61

FR 26501, May 28, 1996) for open water seismic operations in the

Beaufort Sea, NMFS released an EA that addressed the impacts on the

human environment from issuance of the authorization and the

alternatives to the proposed action. No comments were received on that

document and, on July 18, 1996, NMFS concluded that neither

implementation of the proposed authorization for the harassment of

small numbers of several species of marine mammals incidental to

conducting seismic surveys during the open water season in the U.S.

Beaufort Sea nor the alternatives to that action would significantly

affect the quality of the human environment. As a result, the

preparation of an EIS on this action is not required by section 102(2)

of NEPA or its implementing regulations.

While this year's activity is a continuation of the seismic work

conducted between 1996 and 1998, NMFS determined that a new EA was

warranted based on the proposed construction of the Northstar project,

the collection of data from 1996 through 1998 on Beaufort Sea marine

mammals and the impacts of seismic activities on these mammals, and the

analysis of scientific data indicating that bowheads avoid nearshore

seismic operations by up to about 20 km (10.8 nm). Accordingly, a

review of the impacts expected from the issuance of an IHA has been

assessed in detail in the EA and in this document, and NMFS has

determined that there will be no more than a negligible impact on

marine mammals from the issuance of the harassment authorization and

that there will not be any unmitigable impacts to subsistence

communities, provided the mitigation measures required under the

authorization are implemented. As a result, NMFS has again determined

that neither implementation of the authorization for the harassment of

small numbers of several species of marine mammals incidental to

conducting seismic surveys during the open water season in the U.S.

Beaufort Sea nor the alternatives to that action would significantly

affect the quality of the human environment. As a result, the

preparation of an EIS on this action is not required by section 102(2)

of NEPA or its implementing regulations.

Conclusions

Based on the evidence provided in the application, the EA, and this

document, and taking into consideration the comments submitted on the

EA, application, and proposed authorization notice, NMFS has determined

that there will be no more than a negligible impact on marine mammals

from the issuance of the harassment authorization to Western

Geophysical and that there will not be any unmitigable adverse impacts

to subsistence communities, provided the mitigation measures required

under the authorization are implemented. NMFS has determined that the

short-term impact of conducting seismic surveys in the U.S. Beaufort

Sea will result, at worst, in a temporary modification in behavior by

certain species of cetaceans and possibly pinnipeds. While behavioral

and avoidance reactions may be made by these species in response to the

resultant noise, this behavioral change is expected to have a

negligible impact on the animals.

While the number of potential incidental harassment takes will

depend on the distribution and abundance of marine mammals (which vary

annually due to variable ice conditions and other factors) in the area

of seismic operations, the number of potential harassment takings is

estimated to be small. In addition, no take by death and/or serious

injury is anticipated, and the potential for temporary or permanent

hearing impairment will be avoided through the incorporation of the

mitigation measures mentioned in this document and required by the

authorization. No rookeries, mating grounds, areas of concentrated

feeding, or other areas of special significance for marine mammals

occur within or near the planned area of operations during the season

of operations.

Because bowhead whales are east of the seismic area in the Canadian

Beaufort Sea until late August/early September, seismic activities are

not expected to impact bowhead whales or the subsistence hunting of

bowhead whales prior to that date. After September 1, 1999, if seismic

activities continue beyond that date, aerial survey flights for bowhead

whale assessments will be initiated. Depending upon the date of

cessation of seismic activities (expected to be no later than September

10, 1999), NMFS estimates that fewer than 750 bowheads will be harassed

incidental to seismic-related activities.

Appropriate mitigation measures to avoid an unmitigable adverse

impact on the availability of bowhead whales for subsistence needs have

been the subject of consultation between Western Geophysical and

subsistence users. This C&AA, which consists of three main components:

(1) Communications, (2) conflict avoidance, and (3) dispute resolution,

has been concluded for the 1999 open-water seismic season.

Also, while open-water seismic exploration in the U.S. Beaufort Sea

has some potential to influence seal hunting activities by residents of

Nuiqsut, because (1) the peak sealing season is during the winter

months, (2) the main summer sealing is off the Colville Delta, and (3)

the zone of influence by seismic sources on seals and beluga is fairly

small, NMFS believes that Western Geophysical's seismic survey will not

have an unmitigable adverse impact on the availability of these stocks

for subsistence uses.

Since NMFS is assured that the taking would not result in more than

the incidental harassment (as defined by the MMPA Amendments of 1994)

of small numbers of certain species of marine mammals, would have only

a negligible impact on these stocks, would not have an unmitigable

adverse impact on the availability of these stocks for subsistence

uses, and would result in the least practicable impact on the stocks,

NMFS has determined that the requirements of section 101(a)(5)(D) of

the MMPA have been met and the authorization can be issued.

Authorization

Accordingly, NMFS has issued an IHA to Western Geophysical for the

herein described seismic survey during the 1999 open water season

provided the mitigation, monitoring, and reporting requirements

described in this document and in the IHA are undertaken.

Dated: July 20, 1999.

Art Jeffers,

Acting Director, Office of Protected Resources, National Marine

Fisheries Service.

[FR Doc. 99-19462 Filed 7-29-99; 8:45 am]

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