Small Takes of Marine Mammals Incidental to Specified Activities; Seismic Hazards Investigation in Southern California

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[I.D. 021699A]

Small Takes of Marine Mammals Incidental to Specified Activities;

Seismic Hazards Investigation in Southern California

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.

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

SUMMARY: NMFS has received a request from the U.S. Geological Survey

(USGS) for an authorization to take small numbers of marine mammals by

harassment incidental to collecting marine seismic-reflection data

offshore from southern California. Under the Marine Mammal Protection

Act (MMPA), NMFS is requesting comments on its proposal to authorize

the USGS to incidentally take, by harassment, small numbers of marine

mammals in the afore mentioned area for a 2-week period between May and

July 1999.

DATES: Comments and information must be received no later than April 5,

1999.

ADDRESSES: Comments on the application should be addressed to Donna

Wieting, Acting Chief, Marine Mammal Division, Office of Protected

Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910-3225.

A copy of the application may be obtained by writing to this address or

by telephoning one of the contacts listed here.

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

713-2055, or Christina Fahy, NMFS, 562-960-4017.

SUPPLEMENTARY INFORMATION:

Background

Sections 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, 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

[[Page 10645]]

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 that the permissible methods of

taking and requirements pertaining to the 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.''

Subsection 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. The MMPA now defines ``harassment'' as:

...any act of pursuit, torment, or annoyance which (a) has the

potential to injure a marine mammal or marine mammal stock in the

wild; or (b) 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.

Subsection 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

small numbers of marine mammals. Within 45 days of the close of the

comment period, NMFS must either issue or deny issuance of the

authorization.

Summary of Request

On January 15, 1999, NMFS received a request from the USGS for

authorization to take small numbers of several species of marine

mammals by harassment incidental to collecting marine seismic-

reflection data offshore from southern California. Seismic data will be

collected during a 2-week period between May and July 1999, to support

studies of the regional landslide and earthquake hazards and to

understand how saltwater invades

coastal aquifers. A revised request was received on February 11,

1999.

Background

The USGS proposes to conduct a high-resolution seismic survey

offshore from Southern California, for a 2-week period between May and

July 1999. The USGS would like to collect seismic-reflection data to

investigate: (1) the hazards posed by landslides and potential

earthquake faults in the nearshore region from Santa Barbara to San

Diego and (2) the invasion of seawater into freshwater aquifers that

are critical to the water supply for people within the Los Angeles-San

Pedro area. Both of these tasks are multi-year efforts that require

using a small airgun.

Coastal Southern California is the most highly populated urban area

along the U.S. Pacific coast. The primary objective of the USGS

research is to provide information to help mitigate the earthquake

threat to this area. The USGS emphasizes that the goal is not

earthquake prediction but rather an assistance in determining what

steps might be taken to minimize the devastation should a large quake

occur. The regional earthquake threat is known to be high, and a major

earthquake could adversely affect the well being of a large number of

people.

Important geologic information that the USGS will derive from this

project's seismic-reflection data concerns how earthquake deformation

is distributed offshore, that is, where the active faults are and what

the history of movement along them has been. This should improve

understanding of the shifting pattern of deformation that occurred over

both the long term (approximately the last 100,000 years) and short

term (the last few thousand years). The USGS seeks to identify actively

deforming structures that may constitute significant earthquake

threats. The USGS also proposes to locate offshore landslides that

might affect coastal areas. Not only major subsea landslides might

affect the footings of coastal buildings, but also very large slides

can generate local tsunamis. These large sea waves can be generated by

seafloor movement that is produced either by landslides or by

earthquakes. Knowing where large slides have occurred offshore will

help locate areas susceptible to wave inundation.

Some faults that have produced earthquakes lie entirely offshore or

extend into offshore areas where they can be studied using high-

resolution seismic-reflection techniques. An example is the Rose Canyon

fault, which extends through the San Diego area, and is considered to

be the primary earthquake threat. This fault extends northward from La

Jolla, beneath the inner continental shelf, and appears again onshore

in the Los Angeles area. This fault and others like it near shore could

generate moderate (M5-6) to large (M6-7) earthquakes.

Knowing the location and geometry of fault systems is critical to

estimating the location and severity of ground shaking. Therefore the

results of this project will contribute to decisions involving land

use, hazard zonation, insurance premiums, and building codes.

The proposed work is in collaboration with scientists at the

Southern California Earthquake Center, which analyzes faults and

earthquakes in onshore regions, and with scientists at the Scripps

Institute of Oceanography, who measure strain (incremental movement) on

offshore faults.

The USGS also wants to collect high-resolution seismic- reflection

data to locate the sources and pathways of seawater that intrudes into

freshwater aquifers below San Pedro. Ground water usage in the Los

Angeles basin began in the mid-1800s. Today, more than 44,000 acre-feet

of freshwater each year are extracted from the aquifers that underlie

just the city of San Pedro. Extracting freshwater from coastal aquifers

causes offshore salt water to flow toward areas of active pumping. To

limit this salt-water intrusion, the Water Replenishment District and

water purveyors in San Pedro are investing $2.7 million per year to

inject freshwater underground to establish a zone of high water

pressure in the aquifer. The resulting zone of high pressure will form

a barrier between the invasive saltwater and the productive coastal

aquifers.

USGS scientists in San Diego are working with the Los Angeles

County Department of Public Works and the Water Replenishment District

to develop a ground-water simulation model to predict fluid flow below

San Pedro and nearby parts of the Los Angeles Basin. This model will

eventually be used in managing water resources. The accuracy of the

present model, however, is compromised by a paucity of information

about aquifer geometry and about other geologic factors that might

affect fluid flow. Data the USGS collects will be used to improve

three-dimensional, fluid-flow models to aid management of water

resources.

Fieldwork described here will be the third airgun survey that the

USGS has conducted under close supervision by marine-mammal biologists.

In March 1998, the USGS used a large (6500 in3; 106 liters)

airgun array in and around Puget Sound to study the regional earthquake

hazard. The USGS employed 12 biologists, who worked on two ships

continuously to oversee airgun operations. On several occasions the

USGS shut off the airguns when marine mammals entered safety zones that

had been stipulated by NMFS under an Incidental Harassment

Authorization (IHA), and, when mammals left these zones, the USGS

gradually ramped up the array as required to avoid harming

[[Page 10646]]

wildlife. Marine-mammal biologists reported that, during the survey, no

overt distress was evident among the dense marine mammal populations,

and, afterward, no unexplained marine mammal strandings occurred.

In August 1998, the USGS surveyed offshore from Southern

California, using a small airgun (40 in3; 655

cm3). Two marine mammal biologists oversaw this activity,

and the survey the USGS proposes will be conducted with similar

oversight.

Experimental Design

Marine studies conducted by the USGS focus on areas where natural

hazards have their greatest potential impact on society. In Southern

California, USGS studies will concern four areas. The first area in

priority is the coastal zone and continental shelf between Los Angeles

and San Diego, where much of the hazard appears to be associated with

strike-slip faults, such as the Newport-Inglewood and Palos Verdes

faults. The second study area lies offshore, in the Santa Monica, San

Pedro, and San Diego Trough deeps, where rapid sedimentation has left a

more complete record, relative to shallow-water areas, that the USGS

can use to decipher earthquake history. The third area is the extension

into the Santa Barbara Channel of major elements of onshore geology,

including some large faults. The fourth area is the geologic boundary,

marked generally by the Channel Islands, between the inner California

Borderland (dominated by strike-slip faults) and the Santa Barbara

Channel (dominated by compressional faults). The study proposed here

focuses on the highest priority area, which lie near shore between Los

Angeles and San Diego.

The seismic-reflection survey will last 14 days. From its

experience collecting seismic-reflection data in this general area

during 1998, the USGS has decided to conduct the 1999 survey sometime

within the May through July window. The basis for this decision is its

desire to avoid the gray whale migrations and the peak arrival of other

mysticete whales during late summer.

The USGS has not yet determined the exact tracklines for the

survey, but the USGS does know the areas where airgun use will be

concentrated. Two of these areas are southwest and southeast of Los

Angeles, and the third and largest one is west and northwest of San

Diego. In these areas seismic-reflection data will be collected along a

grid of lines that are about 2 km (1.2 mi) apart.

The USGS proposes to use a small airgun and 200-m (656-ft) long

streamer to collect seismic-reflection data. The potential effect on

marine mammals is from the airgun; mammals cannot become entangled in

the streamer. The USGS will also use a low-powered, high-resolution

seismic system to obtain detailed information about the very shallow

geology. The seismic- reflection system will be aboard a vessel owned

by a private contractor. Ocean-bottom seismometers will be deployed to

measure the velocity of sound in shallow rocks to help unravel the

recent history of fault motion. These seismometers are passive

recorders and pose no threat to the environment.

Ship navigation will be accomplished using satellites of the Global

Positioning System. The survey ship will be able to report accurate

positions, which is important to mitigating the airgun's effect on

marine mammals and to analyzing what impact, if any, airgun operations

had on the environment.

The Seismic Sound Sources

During this survey the USGS will operate two sound sources--an

airgun and a high-resolution Huntec(TM) system. The main

sound source will be a single small airgun of special type called a

generator-injector, or GI-gun (trademark of Seismic Systems, Inc.,

Houston, TX). This type of airgun consists of two small airguns within

a single steel body. The two small airguns are fired sequentially, with

the precise timing required to stifle the bubble oscillations that

typify sound pulses from a single airgun of common type. These

oscillations impede detailed analysis of fault and aquifer structure.

For arrays consisting of many airguns, bubble oscillations are

cancelled by careful selection of airgun sizes. The GI-gun is a mini-

array that is carefully adjusted to achieve the desired bubble

cancellation. Airguns and GI-guns with similar chamber sizes have

similar peak output pressures.

The GI-gun for this survey has two equal-sized chambers of 35

in3 (57 mm3), and the gun will be fired every 12

seconds. Compressed air delivered to the GI-gun will have a pressure of

about 3000 psi. The gun will be towed 12 meters (39.4 ft) behind the

vessel and suspended from a float to maintain a depth of about 1 m (3.3

ft).

The manufacturer's literature indicates that a GI-gun of the size

the USGS will use has a sound-pressure level (SPL) of about 220 dB re 1

Pa-m. In comparison, a 40-in3 (65 mm3)

airgun has an SPL of 216 dB re 1 Pa-m (Richardson et al.,

1995). The GI-gun's output sound pulse has a duration of about 10 ms.

The amplitude spectrum of this pulse, as shown by the manufacturer's

data, indicates that most of the sound energy is at frequencies below

500 Hz. Field measurements by USGS personnel indicate that the GI-gun's

output is low amplitudes at frequencies above 500 Hz. Thus high-

amplitude sound from this source is at frequencies that are outside the

main hearing band of odontocetes and pinnipeds (Richardson et al.,

1995).

The high-resolution Huntec(TM) system uses an

electrically powered sound source. In operation, the sound producing

and recording hardware are towed behind the ship near the seabottom.

The unit emits sound about every 0.5 sec. This system provides highly

detailed information about stratified sediment, so that dates obtained

from fossils in sediment samples can be correlated with episodes of

fault offset. The SPL for this unit is 210 dB re 1 Pa-m. The

output-sound bandwidth is 0.5 kHz to 8 kHz, with the main peak at 4.5

kHz.

The Need for 24-hour Seismic Operations

Operating less than 24 hours each day incurs substantially

increased cost for the leased ship, which the USGS cannot afford. The

ship schedule provides a narrow time window for this project; other

experiments are already scheduled to precede and follow this one. Thus,

the USGS is not able arbitrarily to extend the survey time to include

large delays for dark or poor visibility. Reasons for around-the-clock

operation that benefit the environment are (1) when the airgun ceases

to operate, marine mammals might move back into the survey area and

incur an increased potential for harm when operations resume and (2)

daylight-only operations prolong activities in a given area, thus

increasing the likelihood that marine mammals will be harassed. The

1999 survey will require only 2 weeks, and it will be spread out

geographically from Los Angeles to San Diego, so no single area will

see long-term activity. In the view of the USGS, the best course is to

complete the experiment as expeditiously as possible. For these

reasons, the USGS requests that the IHA allow 24-hour operations.

Description of Habitat and Marine Mammals Affected by the Activity

The Southern California Bight supports a diverse assemblage of 29

species of cetaceans (whales, dolphins and porpoises) and 6 species of

pinnipeds (seals and sea lions). The species of marine mammals that are

likely to be present in the seismic research area include the

bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus

delphis), killer

[[Page 10647]]

whale (Orcinus orca), Pacific white-sided dolphin (Lagenorhynchus

obliquidens), northern right whale dolphin (Lissodelphis borealis),

Risso's dolphin (Grampus griseus), pilot whales (Globicephala

macrorhynchus), Dall's porpoise (Phocoenoides dalli), sperm whale,

humpback whale (Megaptera novaengliae), gray whale (Eschrichtius

robustus), blue whale, minke whale (Balaenoptera acutorostrata), fin

whales (Balaenoptera physalus), harbor seal (Phoca vitulina), elephant

seal (Mirounga angustirostris), northern sea lion (Eumetopias jubatus),

and California sea lion (Zalophus californianus), northern fur seal

(Callorhinus ursinus) and sea otters (Enhydra lutris). General

information on these latter species can be found in the USGS

application and in Barlow et al. (1997). Please refer to those

documents for information on the biology, distribution, and abundance

of these species.

Potential Effects of Seismic Surveys on Marine Mammals

Discussion

Seismic surveys are used to obtain data about rock formations up to

several thousands of feet deep. These surveys are accomplished by

transmitting sound waves into the earth, which are reflected off

subsurface formations and recorded with detectors in the water column.

A typical marine seismic source is an airgun array, which releases

compressed air into the water creating an acoustical energy pulse that

is directed downward toward the seabed. Hydrophones spaced along a

streamer cable just below the surface of the water receive the

reflected energy from the subsurface formations and transmit data to

the seismic vessel. Onboard the vessel, the signals are amplified,

digitized, and recorded on magnetic tape.

Disturbance by seismic noise is the principal means of taking by

this activity. Vessel noise may provide a secondary source. Also, the

physical presence of vessel(s) could also lead to some non-acoustic

effects involving visual or other cues.

Depending upon ambient conditions and the sensitivity of the

receptor, underwater sounds produced by open-water seismic operations

may be detectable some 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. An incidental harassment take is presumed to

occur when marine mammals in the vicinity of the seismic source (or

vessel) react to the generated sounds or to visual cues.

Seismic pulses are known to cause some species of whales, including

gray whales, to behaviorally respond within a distance of several

kilometers (Richardson et al., 1995). Although some limited masking of

low-frequency sounds is a possibility for those species of whales using

low frequencies for communication, the intermittent nature of seismic

source pulses will limit the extent of masking. Bowhead whales, for

example, 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).

When the received levels of noise exceed some behavioral reaction

threshold, cetaceans will show disturbance reactions. The levels,

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

between and within species, individuals, locations and seasons.

Behavioral changes may be subtle alterations in surface-dive-

respiration 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.

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

it is not known whether a marine mammal very close to the airgun would

be at risk of permanent hearing impairment, temporary threshold shift

is a theoretical possibility for animals very close to the airgun.

However, planned monitoring and mitigation measures (described later in

this document) are designed to detect marine mammals occurring near the

seismic source(s) and to avoid, to the greatest extent practicable,

exposing them to sound pulses that have any possibility of causing

hearing damage.

Maximum Sound-Exposure Levels for Marine Mammals

At this time, the USGS lacks detailed measurement of sound-

transmission loss for the southern California offshore, so the USGS

estimated how SPL varies with distance from the airgun by assuming that

sound decays according to 25log(R). The coefficient 25 accounts

approximately for the attenuation that is caused by the sound

interacting with the seabottom. The USGS used this procedure to derive

safety zone estimates based on the 220 dB SPL produced by the GI-gun,

the larger of the two sound sources the USGS plans to use.

Loud continuous sounds can damage the hearing of marine mammals.

However, the adverse effects of sound on mammals have been documented

for exposure times that last for tens of seconds or minutes, but

effects have not been documented for the brief pulses typical of the

GI-gun (10 ms) and the Huntec(TM) system (0.3 ms). NMFS

considers that the maximum SPLs to which marine mammals can be exposed

from impulse sounds are 180 dB re 1 Pa-m RMS for mysticetes

and sperm whales, and 190 dB re 1 Pa-m RMS for odontocetes and

pinnipeds.

Assuming that the 25LogR decay that the USGS used to estimate safe

distances from the airgun is correct, this indicates that an SPL of 190

dB re 1 Pa-m is attained about 16 m (52.5 ft) away from the

airgun, and an SPL of 180 dB re 1 Pa-m is attained at about 40

m (131 ft) away. However, for precautionary reasons during field

operations, the USGS proposes that, at all times, the safe distance for

odontocetes and pinnipeds be 50 m (164 ft) and for mysticetes, 100 m

(328 ft).

Estimated Number of Potential Harassments of Marine Mammals

The zone of influence for the GI-gun is defined to be the circle

whose radius is the distance from the gun where the SPL reduces to 160

dB re 1 Pa-m. For the assumed 25LogR, the zone of influence is

a circle with a radius of 250 m (820 ft). Based on estimated marine

mammal populations within the survey area and on the number of

individuals that were observed during the 1998 survey, the USGS

estimates that up to 5 killer whales, 10 minke whales, 10 sea otters,

50 northern sea lions, 100 northern fur seals, 100 northern elephant

seals, 100 Dall's porpoise, 100 Risso's dolphins, 100 northern right-

whale dolphins, 100 Pacific white-sided dolphins, 100 bottlenosed

dolphins, 200 California sea lions, 200 Pacific harbor seals, and 6,000

common dolphins may be harassed incidental to the USGS survey. No

marine mammals will be seriously injured or killed as a result of the

survey.

Proposed Mitigation of Potential Environmental Impact

To avoid potential harassment of marine mammals, a safety zone will

be established and monitored continuously by biologists, and the USGS

will shut off the airguns whenever the ship and a marine mammal

converge closer than

[[Page 10648]]

the previously mentioned safety distance. For pinnipeds, if the seismic

vessel approaches a pinniped, the 50 m (164 ft) safety radius will be

maintained; however, if a pinniped approaches the towed airgun, NMFS

proposes that it will not require the USGS to shutdown the airgun, but

will require the USGS to monitor the interaction to ensure the animal

does not show signs of distress. Experience indicates that pinnipeds

will come from great distances to inspect seismic operations. Seals

have been observed swimming within airgun bubbles, 10 m (33 ft) away

from active arrays, apparently unaffected. Although airgun oprations

will be terminated if the pinnipeds show obvious distress, the USGS

will conduct observations on effects the airguns may have on the

animals.

The USGS plans to have marine biologists aboard the ship who will

have the authority to stop airgun operations when a mammal enters the

safety zone.

During seismic-reflection surveying, the ship's speed will only be

4 to 5 knots, so that when the airgun is being discharged, nearby

marine mammals will have gradual warning of the vessel's approach and

can move away. Finally, NMFS will coordinate with the local stranding

network to determine whether strandings can be related to the seismic

operation.

Monitoring and Reporting

Biologists who oversaw the previous USGS airgun surveys were

affiliated with the Cascadia Research Collective in Olympia,

Washington. Because of their experience with the operations, the USGS

prefer to employ these scientists again, but this preference is subject

to contracting arrangements.

Monitoring marine mammals while the airguns are active will be

conducted 24 hours each day. Two trained marine mammal observers will

be aboard the seismic vessel to mitigate the potential environmental

impact from airgun use and to gather data on the species, number, and

reaction of marine mammals to the airgun. Each observer will work 6

hours during daylight and 6 hours at night. During daylight, observers

will use 7x50 binoculars with internal compasses and reticules to

record the horizontal and vertical angle to sighted mammals. Night-time

operations will be conducted with a commercial hand-held light

magnification scope. Monitoring data to be recorded during airgun

operations include the observer on duty, weather conditions (such as

Beaufort sea state, wind speed, cloud cover, swell height,

precipitation, and visibility). For each mammal sighting, the observer

will record the time, bearing and reticule readings, species, group

size, and the animal's surface behavior and orientation. Observers will

instruct geologists to shut off the airgun array whenever a marine

mammal enters its respective safety zone.

Possible Modifications or Alternatives to the Proposed Survey

The instructions for this permit request stipulate that the USGS

consider alternatives to the proposed experiment. Options to change the

activity are limited, but the USGS might conduct it in some other way,

such as with a low-powered source or in a different season.

To abandon this study altogether is a poor option. In the

introductory section of this application, the USGS described the

societal relevance of this project and the benefits to scientists in

understanding the regional earthquake hazard and to city planners in

establishing building codes. Another facet of this study is

understanding coastal aquifers and knowing how to stem the intrusion of

salt water into them. If the project were canceled, such information

would be unavailable.

The source strength might be reduced to limit the environmental

impact. However, the proposed airgun size is already small, and the

problem with this option is that the USGS cannot significantly reduce

the source strength without jeopardizing the success of this survey.

This judgment is based on USGS decades-long experience with seismic-

reflection surveys, but especially on the 1998 survey that was

conducted in the same general area as outlined here. If the USGS were

to reduce the airgun size and then fail to obtain the required

information, another survey would need to be conducted, and this would

double the potential impact on marine mammals.

This project could be carried out at some other time of year, and

the USGS is open to suggestions. In this pursuit, the USGS talked with

biologists to find out the best time for the project to be conducted.

The USGS wants to avoid the gray whale migrations and the mid-summer

arrival of other mysticete species because, while these other species

remain mostly in the area of the Channel Islands, some individuals

venture closer to the mainland. An important point is that biologists

can best prevent harm to mammals when daylight is long, that is, near

the solstice.

Consultation

Under section 7 of the Endangered Species Act, NMFS has begun

consultation on the proposed issuance of an IHA. Consultation will be

concluded upon completion of the comment period and consideration of

those comments in the final determination on issuance of an

authorization.

Conclusions

NMFS has preliminarily determined that the short-term impact of

conducting marine seismic-reflection data in offshore southern

California will result, at worst, in a temporary modification in

behavior by certain species of pinnipeds and cetaceans. While

behavioral modifications may be made by certain species of marine

mammals to avoid the resultant noise from the seismic airgun, this

behavioral change is expected to have a negligible impact on the

animals.

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

takes will be at the lowest level practicable due to the incorporation

of the mitigation measures previously mentioned. No known 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.

Proposed Authorization

NMFS proposes to issue an IHA to the USGS for the possible

harassment of small numbers of several species of marine mammals

incidental to collecting marine seismic-reflection data offshore from

southern California, provided the above-mentioned mitigation,

monitoring, and reporting requirements are incorporated. NMFS has

preliminarily determined that the proposed activities would result in

the harassment of only small numbers of each of several species of

marine mammals and will have no more than a negligible impact on these

marine mammal stocks.

Information Solicited

NMFS requests interested persons to submit comments, information,

and suggestions concerning this request (see ADDRESSES).

Dated: March 1, 1999.

P. Michael Payne,

Acting Deputy Director, Office of Protected Resources, National Marine

Fisheries Service.

[FR Doc. 99-5497 Filed 3-4-99; 8:45 am]

BILLING CODE 3510-22-F