Small Takes of Marine Mammals Incidental to Specified Activities; Offshore Seismic Activities in the Beaufort Sea

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[I.D. 040497A]

Small Takes of Marine Mammals Incidental to Specified Activities;

Offshore Seismic Activities in the Beaufort Sea

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

Atmospheric Administration (NOAA), Commerce.

ACTION: Notice of receipt of application and proposed authorization for

a small take exemption; request for comments.

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SUMMARY: NMFS has received a request from the BP Exploration (Alaska)

900 East Benson Boulevard, Anchorage, AK 99519 (BPXA) for a renewal of

an authorization to take small numbers of marine mammals by harassment

incidental to conducting seismic surveys in and near the Northstar

Unit, in the Beaufort Sea in state and Federal waters. Under the Marine

Mammal Protection Act (MMPA), NMFS is requesting comments on its

proposal to authorize BPXA to incidentally take, by harassment, small

numbers of bowhead whales and other marine mammals in the above

mentioned areas during the open water period of 1997.

DATES: Comments and information must be received no later than May 22,

1997.

ADDRESSES: Comments on the application should be addressed to Michael

Payne, Chief, Marine Mammal Division, Office of Protected Resources,

NMFS, 1315 East-West Highway, Silver Spring, MD 20910-3225. A copy of

the application, an environmental assessment (EA), an informal section

7 consultation, the 90-day Report, and a list of references used in

this document may be obtained by writing to this address or by

telephoning one of the contacts listed below.

FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead, Office of

Protected Resources, NMFS, (301) 713-2055, Brad Smith, Western Alaska

Field Office, NMFS, (907) 271-5006.

SUPPLEMENTARY INFORMATION:

Background

Section 101(a)(5) (A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)

directs the Secretary of Commerce to allow, upon request, the

incidental, but not intentional taking of marine mammals by U.S.

citizens who engage in a specified activity (other than commercial

fishing) within a specified geographical region if certain findings are

made and either regulations are issued or, if the taking is limited to

harassment, 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), will not have an

unmitigable adverse impact on the availability of the species or

stock(s) for subsistence uses, and 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 for

activities 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 5, 1997, NMFS received an application from BPXA requesting

a 1-year renewal of their authorization for

[[Page 19554]]

the harassment of small numbers of several species of marine mammals

incidental to conducting seismic surveys during the open water season

within and near the Northstar Unit, in the Beaufort Sea between

145 deg. 30'W and 150 deg. 30'W, in U.S. waters. Weather permitting,

the survey is expected to take place between approximately July 1 and

October 20, 1997. A detailed description of the work planned is

contained in the application (BPXA 1997) and is available upon request

(see ADDRESSES). Description of Habitat and Marine Mammal Affected by

the Activity

A detailed description of the Beaufort Sea ecosystem and its

associated marine mammals can be found in the EA prepared for this

authorization (BPXA 1996b) or in other documents (Minerals Management

Service (MMS) 1992, 1996) and need not be repeated here. A copy of the

EA is available upon request (see ADDRESSES).

Marine Mammals

The Beaufort/Chukchi Seas support a diverse assemblage of marine

mammals including bowhead whales (Balaena mysticetus), gray whales

(Eschrichtius robustus), belukha (Delphinapterus leucas), ringed seals

(Phoca hispida), spotted seals (Phoca largha) and bearded seals

(Erignathus barbatus). Descriptions of the biology and distribution of

these species, and others, can be found in several other documents

(BPXA 1996b, 1997, Lentfer 1988, MMS 1992, NMFS 1990 and 1996, Small

and DeMaster 1995). Please refer to those documents for information on

these species. Potential Effects of Seismic Surveys on Marine Mammals.

Disturbance by seismic noise is the principal means of taking by

this activity. Vessels and aircraft will provide a secondary source of

noise.

Deep seismic surveys are used to obtain data about formations

several thousands of feet deep. The physical presence of vessels and

aircraft could also lead to non-acoustic effects involving visual or

other cues. The proposed seismic operation is an ocean bottom cable

(OBC) survey. OBC surveys involve dropping a cable from a ship to the

ocean bottom. Sensors (hydrophones) are attached to the cable. These

hydrophones are used to detect seismic energy reflected back from

underground rock strata. The original 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 downwards toward the seabed. After sufficient energy has

been recorded to allow accurate mapping of the rock strata, the cable

is 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, including numbers of vessels planned for this

survey, please refer to the application (BPXA 1997).

Depending upon ambient conditions and the sensitivity of the

receptor, underwater sounds produced by open water seismic operations

may be detectable some 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 masking a signal of

comparable frequency (BPXA 1997). 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 visual cues.

Seismic pulses are known to cause bowhead whales to behaviorally

respond within a distance of several kilometers (km) (Richardson et al.

1995). Although some limited masking of low-frequency sounds (e.g.,

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

source pulses (1 sec every 6-12 sec) will limit the extent of masking.

Bowhead whales are known to continue calling in the presence of seismic

survey sounds, and their calls can be heard between seismic pulses

(Richardson et al. 1986). Masking effects are expected to be absent in

the case of belukhas, given that sounds important to them are

predominantly at much higher frequencies than are airgun sounds (BPXA

1997).

Hearing damage is not expected to occur during the project. It is

not known whether a marine mammal very close to an airgun array would

be at risk of temporary or permanent hearing impairment, but temporary

threshold shift is a theoretical possibility for animals within a few

hundred meters (Richardson et al. 1995) of the source. However, planned

monitoring and mitigation measures (described below) are designed to

detect marine mammals occurring near the array and to avoid exposing

them to sound pulses that have any possibility of causing hearing

damage.

When the received levels of noise exceed some behavioral reaction

threshold, cetaceans will show disturbance reactions (BPXA 1997). The

levels, frequencies, and types of noise that will elicit a response

vary between and within species, individuals, locations and season.

Behavioral changes may be subtle alterations in surface-respiration-

dive cycles. More conspicuous responses include changes in activity or

aerial displays, movement away from the sound source, or complete

avoidance of the area. The reaction threshold and degree of response

are related to the activity of the animal at the time of the

disturbance. Whales engaged in active behaviors such as feeding,

socializing or mating are less likely than resting animals to show

overt behavioral reactions, unless the disturbance is directly

threatening (BPXA 1997).

Bowhead Whales

Various studies (Reeves et al. 1984, Fraker et al. 1985, Richardson

et al. 1986, Ljungblad et al. 1988) have reported that, when an

operating seismic vessel approaches within a few kilometers, most

bowhead whales exhibit strong avoidance behavior and changes in

surfacing, respiration, and dive cycles. Bowheads exposed to seismic

pulses from vessels more than 4.5 miles (mi) (7.5 km) away rarely

showed observable avoidance of the vessel, but their surface,

respiration, and dive cycles appeared altered in a manner similar to

that observed in whales exposed at a closer distance (BPXA 1996).

Within a 3.7-60 mi (6-99 km) range, it has not been possible to

determine a specific distance at which subtle behavioral changes no

longer occur (Richardson and Malme 1993), given the high variability

observed in bowhead whale behavior (BPX 1996).

Preliminary analysis of the results from BPXA's 1996 seismic

monitoring program does not provide conclusive evidence about the

radius of avoidance of bowheads to the seismic program. The peak number

of bowhead sightings was 10-20 km (6.2-12.3 mi) from shore during no-

seismic periods and 20-30 km (12.3-18.6 mi) from shore during periods

that may have been influenced by seismic noise. This difference was not

statistically significant, but the low numbers of sightings precluded

meaningful interpretation (BPXA 1997).

Gray Whales

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

of bowheads. 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 about 50 percent showed avoidance when the

average received pulse level was 170 dB (re 1 Pa @ 1 m). Less

consistent results were indicated at levels of 140-160 dB.

[[Page 19555]]

Belukha

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

expected to be encountered in the Beaufort Sea. Because its hearing

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

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

or more depending upon frequency (Johnson et al. 1989, Richardson 1991,

1995), belukha are not predicted to be strongly influenced by seismic

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

airgun sounds may be audible to belukha at large distances (Richardson

1991, 1995).

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 (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). 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 97

dB (re 1 Pa @ 1 m) at 100 Hz (Kastak and Schusterman, 1995a,

b).

Because no studies to date have focused on pinniped reaction to

underwater noise from pulsed, seismic arrays in open water (Richardson

et al. 1991, 1995), as opposed to in-air exposure to continuous noise,

substantive conclusions are not possible at this time. However,

assuming a sound pressure level needed to be 80-100 dB over its

threshold in order to cause annoyance and 130 dB for injury (pain), as

is the current thought based upon human studies (ARPA and NMFS 1995),

then it appears unlikely that pinnipeds would be harassed or injured by

low frequency sounds from a seismic source unless they were within

close proximity of the array. For permanent injury, marine mammals

would need to remain in the high noise field for extended periods of

time. Existing evidence also suggests that, while they may be capable

of hearing sounds from seismic arrays, seals 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/WDFW 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 Western Beaufort Sea waters, pinnipeds have previously been

exposed to seismic noise, and may not react to it, after initial

exposure.

Numbers of Marine Mammals Expected To Be Taken

Based upon calculations provided in their application, BPXA

estimates that the following numbers of marine mammals may be subject

to Level B harassment, as defined in 50 CFR 216.3:

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Harassment takes in 1997

Species Population size ------------------------------------------------

Possible Probable

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Bowhead.............................. 8,000................... 400 200

Gray whale........................... 23,000.................. 200,000................ 10 5

Bearded seal......................... >300,000................ 50 30

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Effects of Seismic Noise and Other Activities on Subsistence Needs

The disturbance and potential displacement of marine mammals by

sounds from seismic activities is the principle concern related to

subsistence use of the area. The harvest of marine mammals (mainly

bowhead whales, ringed seals, and bearded seals) is central to the

culture and subsistence economies of the coastal North Slope

communities (BPXA 1997). In particular, if migrating bowhead whales are

displaced farther offshore by elevated noise levels, this could make

harvest of these whales more difficult and dangerous for hunters. The

harvest could also be affected if bowheads are more skittish when

exposed to seismic noise (BPXA 1997).

Nuiqsut is the community closest to the area of the proposed

activity, and only harvests bowhead whales during the fall whaling

season. Nuiqsut whalers typically take zero to three whales each season

(four in 1995; two in 1996), with a trend toward larger harvests in the

most recent years (BPXA 1997). Nuiqsut whalers concentrate their

efforts on areas north and east of Cross Island, generally in water

depths greater than 65 ft (20 m). Cross Island is the principle field

camp location for Nuiqsut whalers and is located within the general

area of the proposed seismic area. Thus, the possibility and timing of

potential seismic operations in the Cross Island area requires BPXA to

provide NMFS with a Plan of Cooperation with North Slope residents

(also called the Communications and Avoidance Agreement) to avoid any

unmitigable adverse impact on subsistence needs.

Whalers from the village of Kaktovik search for whales east, north

and west of the village. Kaktovik is located 45 mi (72 km) east of the

easternmost end of the planned seismic exploration area. The

westernmost reported harvest location was about 13 mi (21 km) west of

Kaktovik, near 70 deg.10' N, 144 deg.W. That site is about 32 mi (51

km) east of the closest part of the primary seismic exploration area

(BPXA 1997). However, it should be noted that the eastern portion of

the geographic area noted by BPXA for the authorization extends

considerably closer to this harvest area.

Whalers from the village of Barrow search for bowhead whales much

further from the planned seismic area, >125 mi (>200 km) west (BPXA

1997).

The location of the proposed seismic activity is south of the main

westward migration route of bowhead whales. BPXA (1997) believes that

although

[[Page 19556]]

whales may be able to hear the sounds emitted by the seismic array out

to a distance of 30 mi (50 km) or more, it is unlikely that changes in

migration route will occur at distances of >15 miles (>25 km).

It is recognized that it is difficult to determine the maximum

distance at which reactions occur (Moore and Clark 1992), although

whalers believe that some migrating bowheads are deflected by seismic

operations at distances greater than those documented by scientific

studies done to date. As a result, BPXA is developing a Communications

and Avoidance Agreement with the whalers (see BPXA 1997) to reduce any

potential interference with the hunt. Also, it is believed that the

monitoring plan proposed by BPXA (LGL and Greeneridge 1997) will

provide information that will help resolve uncertainties about the

effects of seismic exploration on the accessibility of bowheads to

hunters.

In addition, while seismic exploration in the Northstar Unit has

some potential to influence subsistence seal hunting activities, the

peak season for seal hunting is during the winter months when the

harvest consists almost exclusively of ringed seals (BPXA 1997). In

summer, boat crews hunt ringed, spotted and bearded seals (BPXA 1997).

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 (BPXA 1997). 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 (BPXA

1997).

Mitigation

BPXA proposes to continue the mitigation program carried out in

1996. BPXA plans to use biological observers to monitor marine mammal

presence in the vicinity of the seismic array. To avoid the potential

for serious injury to marine mammals, BPXA will power down the seismic

source if pinnipeds are sighted:

(a) within 260 m (853 ft) of an array of >720 in3 and

1,320 in3 at 2.5 m (8.3 ft) depth;

(b) within 130 m (426 ft) of that array operating at >2.5 m (8.3

ft) depth;

(c) within 130 m (426 ft) of an array of >120 in3 and

720 in3 operating at 2.5 m (8.3 ft)

depth;

(d) within 60 m (197 ft) of that array operating at 120 in3.

BPXA will power down the seismic source if bowhead, gray, or

belukha whales are sighted:

(a) within either 1020 m (3346 ft) of an array >720 in3

and 1,320 in3 operating at 2.5m (8.3

ft) depth; or

(b) within 640 m (2100 ft) of that array operating at <2.5 m (8.3

ft) depth or of any smaller airgun source operating at any depth (BPXA

1997).

In addition, BPXA proposes to ramp-up the seismic source to

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

includes airguns of different sizes, the smallest gun will be fired

first. Additional guns will be added at intervals appropriate to limit

the rate of increase in source level to a maximum of 6 dB/min.

Monitoring

As part of their application BPXA has provided a monitoring plan

for assessing impacts to marine mammals from seismic surveys in the

Beaufort Sea (LGL and Greeneridge 1997). As required by the MMPA, this

monitoring plan will be subject to a peer-review panel of technical

experts prior to formal acceptance by NMFS.

Preliminarily, BPXA plans to conduct the following.

Vessel-based Visual Monitoring

A minimum of two biologist-observers aboard each 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 reticulated binoculars during the daytime and with night-

vision equipment during the night (prior to mid-August, there are no

hours of darkness). Individual watches will normally be limited to no

more than 4 consecutive hours. When mammals are detected within a

safety zone designated to prevent injury to the animals (see above),

the geophysical crew leader will be notified so that shutdown

procedures can be implemented immediately.

Aerial Surveys

From September 1, 1997, until the seismic program ends, aerial

surveys will be conducted daily, weather permitting. The primary

objective will be to document the occurrence, distribution, and

movements of bowhead and belukha 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 for assessing 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 1,000 ft (300 m) above sea

level. BPXA proposes to avoid overflights of the Cross Island area

where whalers from Nuiqsut are based during their fall whale hunt.

The daily aerial surveys are proposed to cover two grids: A grid of

12 north-south lines spaced 5 mi (8 km) apart and extending from about

12.5 mi (20 km) west of the western side of the then-current seismic

exploration area to 30 mi (50 km) east of its eastern edge, and from

the barrier islands north to approximately the 100 m (328 ft) depth

contour;

A grid of 4 survey lines within the above region, also spaced 5 mi

(8 km) apart and mid-way between the longer lines, to provide more

intensive coverage of the area of the seismic operations and immediate

surrounding waters.

Acoustical Measurements

The acoustic measurement program proposed for 1997 is designed to

be a sequel to the program conducted at Northstar in 1996 (see BPXA

1996a and 1997, LGL and Greeneridge 1996b and 1997 for a description of

the work proposed). The acoustic measurement program is planned to

include (1) retrieval of bottom recorders deployed in 1996 and analysis

of usable data contained in those recorders, (2) boat-based acoustic

measurements, and (3) OBC-based acoustic measurements. Two differences

between the 1996 and 1997 programs are that BPXA does not plan to

deploy sonobuoys during the 1997 aerial surveys, and will not redeploy

the bottom-mounted recorders (5 of the 10 units remain non-functional

on the sea bottom).

The boat-based acoustical measurement program is proposed for a 7-

day period in mid-to late-August 1996. 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(s)

of airgun array(s) to be used in 1977 as a function of distance and

aspect relative to the seismic source vessel(s) and relative to water

depth.

(b) To measure the levels and frequency composition of the vessel

sounds emitted by vessels used regularly during the 1977 program,

excluding vessels whose sounds were characterized adequately in 1996.

(c) To obtain additional site-specific ambient noise data, which

determine signal-to-noise ratios for seismic and

[[Page 19557]]

other acoustic signals at various ranges from their sources.

New to the acoustic measurement program for 1997 is a plan to test

the feasibility to use the hydrophones in the OBC to measure received

levels and characteristics of airgun pulses over a large area (about

3.3X5.9 km) simultaneously. If practical, this would provide more

comprehensive data while at the same time reducing the need for labor-

intensive boat-based acoustic measurements.

Estimates of Marine Mammal Take

Estimates of takes by harassment will be made through vessel and

aerial surveys. Preliminarily, BPXA 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) above when no monitoring observations were possible; and (d)

bowheads displaced seaward from the main migration corridor.

Reporting

BPXA will provide an initial report on 1997 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 BPXA within 20 working

days of receipt of the document from the contractor, but no later than

April 30, 1998. The final technical report will contain a description

of the methods, results, and interpretation of all monitoring tasks.

Consultation

Under section 7 of the Endangered Species Act, NMFS completed an

informal consultation on the issuance of an incidental harassment

authorization for this activity on July 15, 1996. A copy of that

document is available upon request (see ADDRESSES).

National Environmental Policy Act (NEPA)

In conjunction with the 1996 notice of proposed authorization (61

FR 26501, May 28, 1996), 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 to BPXA for the harassment

of small numbers of several species of marine mammals incidental to

conducting seismic surveys during the open water season in the

Northstar Unit and nearby waters 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 environmental

impact statement on this action is not required by section 102(2) of

NEPA or its implementing regulations. A copy of the EA is available

upon request (see ADDRESSES).

Conclusions

NMFS has preliminarily determined that the short-term impact of

conducting seismic surveys in the Northstar Unit of the Beaufort Sea

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

certain species of cetaceans. While behavioral modifications may be

made by these species of cetaceans to avoid the resultant noise, this

behavioral change is expected to have a negligible impact on the

animals.

As 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, due to the distribution and abundance of marine

mammals during the projected period of activity and the location of the

proposed seismic activity in waters generally too shallow and distant

from the edge of the pack ice for most marine mammals of concern, the

number of potential harassment takings is estimated to be small. In

addition, no take by injury and/or death is anticipated and the

potential for temporary or permanent hearing impairment will be avoided

through incorporation of the mitigation measures mentioned above. 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 subsistence hunting of bowhead whales prior to

that date. After August 31, 1997, BPXA will initiate aerial survey

flights for bowhead whale assessments. Appropriate mitigation measures

to avoid an unmitigable adverse impact on the availability of bowhead

whales for subsistence needs will be the subject of consultation

between BPXA and subsistence users.

Also, while summer seismic exploration in the Northstar Unit 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 (west and

inshore of Northstar), and (3) the zone of influence by seismic sources

on belukha and seals is fairly small, NMFS believes the Northstar

seismic survey will not have an unmitigable adverse impact on the

availability of these stocks for subsistence uses.

Proposed Authorization

NMFS proposes to issue an incidental harassment authorization for

the 1997 Beaufort Sea open water season for a seismic survey in and

near the Northstar Unit provided the above mentioned mitigation,

monitoring and reporting requirements are incorporated. NMFS has

preliminarily determined that the proposed seismic activity would

result in the harassment of only small numbers of bowhead whales, gray

whales, and possibly belukha whales, bearded seals, and largha seals;

will have a negligible impact on these marine mammal stocks; and will

not have an unmitigable adverse impact on the availability of these

stocks for subsistence uses.

Information Solicited

NMFS requests interested persons to submit comments, information,

and suggestions concerning this request (see ADDRESSES).

Dated: April 16, 1997.

Hilda Diaz-Soltero,

Acting Director, Office of Protected Resources, National Marine

Fisheries Service.

[FR Doc. 97-10254 Filed 4-21-97; 8:45 am]

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