Small Takes of Marine Mammals Incidental to Specified Activities; Taurus Space Launch Vehicles at Vandenberg Air Force Base, CA

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[I.D. 091396A]

Small Takes of Marine Mammals Incidental to Specified Activities;

Taurus Space Launch Vehicles at Vandenberg Air Force Base, CA

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 U.S. Air Force for an

authorization to take small numbers of seals, sea lions and fur seals

by harassment incidental to launches of Taurus space launch vehicles

(Taurus SLV) at Launch Support Complex 576E (LSC- 576E), Vandenberg Air

Force Base, CA (Vandenberg). Under the Marine Mammal Protection Act

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

incidental take, by harassment, of small numbers of Pacific harbor

seals, and other seal and sea lion species, in the vicinity of

Vandenberg for a period of 1 year.

DATES: Comments and information must be received no later than October

25, 1996.

ADDRESSES: Comments on the application should be addressed to Chief,

Marine Mammal Division (Attn: Small Take Program Manager), Office of

Protected Resources, National Marine Fisheries Service, 1315 East-West

Highway, Silver Spring, MD 20910. A copy of the application and

previous Federal Register notices on related actions may be obtained by

writing to this address or by telephoning one of the contacts listed

below.

FOR FURTHER INFORMATION CONTACT: Kenneth Hollingshead, Office of

Protected Resources at 301-713-2055, or Irma Lagomarsino, Southwest

Regional Office at 310-980-4016.

SUPPLEMENTARY INFORMATION:

Background

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

NMFS to allow, upon request, the incidental, but not intentional,

taking of marine mammals by U.S. citizens who engage in a specified

activity (other than commercial fishing) within a specified

geographical region if certain findings are made and regulations are

issued. 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.

Subsection 101(a)(5)(D) of the MMPA established an expedited

process by which U.S. citizens can apply for an authorization to

incidentally take small numbers of marine mammals by harassment for a

period of up to 1 year. The MMPA 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 August 14, 1996, NMFS received a revised application from the

U.S. Air Force, Vandenberg, requesting an authorization for the

harassment of small numbers of harbor seals and possibly California sea

lions and northern elephant seals, incidental to launches of Taurus

SLVs at LSC-576E, Vandenberg. These launches would place commercial

payloads into earth orbit. Because LSC-576E is located north of most

other launch complexes at Vandenberg and because there are oil

production platforms located off the coast to the south of LSC-576E,

missions flown from LSC-576E do not fly directly on their final

southward course. The normal trajectory for a LSC-576E launch is in a

general west-south-west direction away from the coastline. The flight

paths for each 1997 launch will proceed on an initial azimuth of

205 deg. until approximately 24 kilometers (km )(15 miles (mi)) west of

the shoreline. The Taurus SLV will then perform a dogleg maneuver left

to a final mission-specific azimuth of between 180 deg. and 197 deg..

No Taurus SLV launch from LSC-576E will proceed southeast, overflying

San Miguel (SMI) or Santa Rosa islands. Orbital Sciences Corporation

(OSC 1996) anticipates launching two Taurus SLVs during the 1-year

period of validity for this proposed authorization.

As a result of the noise associated with the launch itself and the

resultant sonic boom, there is the potential to cause a startle

response to those harbor seals that haul out on the coastline south and

southwest of Vandenberg and may be detectable to marine mammals in

waters off Vandenberg and to the west of the Channel Islands. Launch

noise would be expected to occur over the coastal habitats in the

vicinity of LSC-576E while a low-level sonic boom may be heard west of

the Channel Islands.

[[Page 50277]]

Description of Habitat and Marine Mammals Affected by Taurus

The Southern California Bight (SCB), including the Channel Islands

area, supports a diverse assemblage of pinnipeds (seals and sea lions)

and cetaceans (whales, dolphins, and porpoises). California sea lions

(Zalophus californianus), northern elephant seals (Mirounga

angustirostris), Pacific harbor seals (Phoca vitulina) and northern fur

seals (Callorhinus ursinus) breed on the Islands, with the largest

rookeries on SMI and San Nicolas Island.

A small breeding population of California sea lions occurs on

Vandenberg, and both sea lions and northern elephant seals are regular

visitors to the shoreline near LSC-576E. A small population of harbor

seals are normal residents of Purisima Point, and southern sea otters

(Enhydra lutra) were censused there during the spring of 19951.

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\1\ Sea otters are under the jurisdiction of the U.S. Fish and

Wildlife Service (USFWS) and not NMFS. Discussions between the

applicant and the USFWS have taken place. Please contact those

agencies for additional information.

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Because it is the only species that hauls out along the Vandenberg

coast in any numbers, the harbor seal is the only marine mammal

anticipated to be incidentally harassed by Taurus SLV launches. A

description of the SCB population of harbor seals and other pinniped

species was provided in the notices published on May 10, 1995 (60 FR

24840) and August 18, 1995 (60 FR 43120), in conjunction with

publication of the previous notices of application for Vandenberg

launch activities and is, therefore, not repeated here. In addition,

new information on harbor seals has been provided more recently in

another notice (61 FR 45404, August 29, 1996) and is summarized below.

Additional information on California marine mammal populations can be

found in Barlow et al. (1995), while marine mammal information specific

to Vandenberg can be found in Roest (1995). Interested reviewers are

encouraged to refer to the documents cited above for the appropriate

discussion. These documents are also available from NMFS (see

ADDRESSES).

Hanan and Beeson (1994) reported 21,462 seals counted on the

mainland coast and islands of California during May and June 1994.

Using that count and Huber et al.'s (1993) correction factor (1.61

times the count) for animals not hauled out gives a best population

estimate of 34,554 harbor seals in California (Barlow et al. 1995). A

total of 19 distinct haulout sites are present on Vandenberg (between

Point Sal and Jalama Beach), although not all sites are used regularly

(Roest 1995). For most of the year, the average number of harbor seals

on the Vandenberg coast is about 330 individuals. This number nearly

doubles during the molting season (June) to roughly 610. The largest

population occurs on South Vandenberg, although a smaller permanent

population is present at two sites near Purisima Point on North

Vandenberg. In general, it appears that the current population of

harbor seals at all 19 haulout sites on Vandenberg peaks at roughly 600

to 800 seals (Air Force 1996).

Maximum numbers of harbor seals at Purisima Point in May/June

average about 40 while the Spur Road site seems to have an average

maximum of from 60 to 80 individuals, and Rocky Point has approximately

70 harbor seals in the spring. More than other sites, Spur Road appears

to have peak numbers in the fall (Air Force 1996, Roest 1995). However,

both the Spur Road and Purisima Point sites are submerged at high tide,

making them unavailable to harbor seals during those times.

Potential Effects of Taurus SLV Launches on Marine Mammals

The effect on harbor seals is expected to be disturbance by sound,

which is anticipated to result in a negligible short-term impact to

small numbers of harbor seals and other pinnipeds that are hauled out

at the time of Taurus SLV launches. No impacts are anticipated to

animals that are in the water at the time of launch. Detailed

descriptions and analyses of the expected impact from rocket launches

on harbor seals and other marine mammals have been provided in previous

notices (60 FR 24840, May 10, 1995; 60 FR 38308, July 26, 1995; 60 FR

43120, August 18, 1995; 60 FR 52653, October 10, 1995; and 61 FR 10727,

March 15, 1996) and are not repeated here. These documents are

available from NMFS (see ADDRESSES).

Based upon measurements made on a March 13, 1994, Taurus SLV launch

by Stewart et al. (1994), the sound exposure level (SEL) recorded at

Purisima Point (40-second duration; 2.24 km (1.4 mi) from the launch

pad) was 108.1 dB (A-weighted: re 20Pa @ 1 m) and 127.4 dB

(unweighted). Twenty of the 23 harbor seals that were hauled out at

this location before the launch fled immediately into the water within

a few seconds after launch. The A-weighted SEL of noise recorded at

Rocky Point (130-second duration; 20.4 km (12.7 mi) from the launch

pad) was 80.0 dB, while the unweighted SEL was 103.9 dB. That noise

included launch noise and possibly a sonic boom below 50 Hz. Twenty of

74 harbor seals that were monitored at Rocky Point fled into the water

within several seconds of the sound arriving there. However, none of

the four young pups that were ashore left the beach nor were they

separated from their mothers. A comparison of the reactions of harbor

seals to sound at the two study sites indicates that the intensity and

duration of reactions of harbor seals to the type of noise associated

with the Taurus SLV was directly related to the intensity of the noise

to which they were exposed (Stewart et al. 1994). Substantially more

seals reacted to the launch noise at Purisima Point than at Rocky

Point. Furthermore, seals at Purisima Point reacted much more

energetically and remained in the water substantially longer at

Purisima Point than did seals at Rocky Point.

Although monitoring was apparently not conducted at Spur Road

(approximately 0.5 mi (804 m) from LSC-576E) in 1994, based upon

measurements for Delta II (Aerospace Corporation 1996) and comparing

these results with Taurus (Stewart et al. 1994), an SEL can be

estimated for Spur Road to be approximately 115 dBA (129 dB

unweighted). While an SPL of 115-120 dBA (re 20Pa @ 1 m) may

cause a short-term (minutes to hours), temporary threshold shift (TTS)

injury to hearing (Richardson et al. 1995), due to the infrequency of

launches at LSC-576E and nearby LSC-2W, TTS-injuries are not expected

to be serious and the animals will recover.

Rocket engine noise over the Northern Channel Islands (NCI) from

the just-launched Taurus SLVs traveling at supersonic speeds should not

affect pinnipeds hauled out on these islands. The Taurus SLV flight

paths will be to the west-southwest away from the California coast.

Sonic boom noise developed as a result of these launches is not

expected to reach the Channel Islands. Low intensity rumbling noise may

reach the Channel Islands with the effect ranging from a simple alert

response to a startle response, which, while unlikely, could result in

movement into the water. The initial Taurus SLV launch from LSC-576E

did not cause a sonic boom over SMI, and there was no response by

pinniped species on SMI (OSC 1996) from launch noise.

Mitigation

Unless constrained by other factors including, but not limited to,

human safety, national security, or launch trajectories, efforts to

ensure minimum negligible impacts of Taurus SLV

[[Page 50278]]

launches on harbor seals and other pinnipeds are proposed for inclusion

in the Incidental Harassment Authorization. These proposals include:

1. Avoidance, whenever possible, of launches during the harbor seal

pupping season of February through May (the scheduled 1997 Taurus SLV

launches are presently scheduled outside this period); and

2. Preference for night launches during the period of the year when

harbor seals are hauled out in any numbers along the coast of North

Vandenberg.

Monitoring and Reporting

The holder of the Incidental Harassment Authorization has proposed

a monitoring program to assess the impact of Taurus SLV launches on the

harbor seal haulouts in the vicinity of Spur Road and Purisima Point.

The applicant proposes to monitor the harbor seal population at these

locations for a period of 3 days prior to launch, immediately following

launch, and for a 3-day period following launch. The monitoring will

consist of a population assessment to determine if there is any

reduction in numbers of animals or a notable change in behavior. Video

and photographic monitoring of daylight launches would also be

conducted if any launch takes place between February and September

1997. The applicant will also perform additional post-launch monitoring

for any launches conducted during the harbor seal pupping season. OSC

will conduct an acoustic (sound propagation) monitoring program for the

first Taurus SLV launch at LSC-576E and the applicant will continue its

program for prediction and monitoring focused sonic boom impacts on the

NCI.

A report on this monitoring program would be required to be

submitted prior to next year's authorization request, unless the

monitoring indicated that serious injuries or mortalities had occurred

that might relate to the launching. In this case, the authorization

would require immediate notification of this fact to the Southwest

Regional Director, NMFS.

Conclusions

Based upon information provided by the applicant, the results from

monitoring a previous Taurus SLV launch, and previous reviews of the

incidental take of harbor seals by this activity, NMFS believes that

the short-term impact of the launching of Taurus SLVs is expected to

result at worst, in a temporary reduction in utilization of the haulout

as seals leave the beach for the safety of the water and may result in

a non-serious TTS injury to those harbor seals hauled out or on the

water surface within approximately 3,000 ft of LSC-576E. The launching

is not expected to result in any reduction in the number of harbor

seals, and they are expected to continue to occupy the same area. In

addition, there will not be any impact on the habitat itself. Based

upon studies conducted for previous space vehicle launches at

Vandenberg, significant long-term impacts on harbor seals at Vandenberg

are unlikely but may eventually be determined by the frequency and

timing of all launches at Vandenberg.

Proposed Authorization

NMFS proposes to issue an incidental harassment authorization for 1

year for launches of Taurus SLV at LSC-576E provided the monitoring and

reporting requirements are implemented. NMFS has preliminarily

determined that the proposed launches of Taurus SLVs at LSC-576E would

result in the Level A harassment taking of only small numbers of harbor

seals, will have a negligible impact on the harbor seal stock and will

not have an unmitigable adverse impact on the availability for

subsistence uses.

Information Solicited

NMFS requests interested persons to submit comments, information,

and suggestions concerning this request (see ADDRESSES).

Dated: September 19, 1996.

Rennie S. Holt,

Acting Director, Office of Protected Resources, National Marine

Fisheries Service.

[FR Doc. 96-24509 Filed 9-24-96; 8:45 am]

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