Skip to Content


Taking of Marine Mammals Incidental to Specified Activities; Central California Seabird Research Operations

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble


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


Notice of proposed authorization for an incidental take authorization; request for comments.


NMFS has received a request from the PRBO Conservation Science (PRBO) for an authorization to take California sea lions, Pacific harbor seals, northern elephant seals and Steller sea lions, by harassment, incidental to central California seabird research operations on Southeast Farallon Island, Ano Nuevo Island, and Point Reyes National Seashore (NS). Under the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an authorization to PRBO to incidentally take, by harassment, small numbers of these species of pinnipeds during the next 12 months.


Comments and information must be received no later than August 27, 2007.


Comments on the application and draft Environmental Assessment (EA) should be addressed to P. Michael Payne, Chief, Permits, Conservation and Education Division, Office of Protected Resources, National Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910-3225, or by telephoning the contact listed here. The mailbox address for providing e-mail comments is Comments sent via e-mail, including all attachments, must not exceed a 10-megabyte file size. A copy of the application, NMFS' draft environmental assessment (EA), and other related documents may be obtained by writing to this address or by telephoning one of the contacts listed here (see FOR Start Printed Page 41295FURTHER INFORMATION CONTACT) and is also available at:​pr/​permits/​incidental.htm#applications.

Start Further Info


Shane Guan, NMFS, (301) 713-2289, ext 137.

End Further Info End Preamble Start Supplemental Information



Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) direct the Secretary of Commerce to allow, upon request, the incidental, but not intentional, taking of small numbers of marine mammals by U.S. citizens who engage in a specified activity (other than commercial fishing) within a specified geographical region if certain findings are made and either regulations are issued or, if the taking is limited to harassment, notice of a proposed authorization is provided to the public for review.

An authorization shall 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 that the permissible methods of taking and requirements pertaining to the mitigation, monitoring and reporting of such taking are set forth. NMFS has defined “negligible impact” in 50 CFR 216.103 as ” impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival.”

Section 101(a)(5)(D) of the MMPA established an expedited process by which citizens of the United States can apply for an authorization to incidentally take small numbers of marine mammals by harassment. Except with respect to certain activities not pertinent here, the MMPA defines “harassment” as:

any act of pursuit, torment, or annoyance which (i) has the potential to injure a marine mammal or marine mammal stock in the wild [Level A harassment]; or (ii) has the potential to disturb a marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, including, but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering [Level B harassment].

Section 101(a)(5)(D) establishes a 45-day time limit for NMFS review of an application followed by a 30-day public notice and comment period on any proposed authorizations for the incidental harassment of 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 December 15, 2006, PRBO submitted an application to NMFS requesting an Incidental Harassment Authorization (IHA) for the possible harassment of small numbers of California sea lions (Zalophus californianus), Pacific harbor seals (Phoca vitulina richardsi), northern elephant seals (Mirounga angustirostris), and Steller sea lions (Eumetopias jubatus) incidental to central

California seabird research operations on Southeast Farallon Island, Ano Nuevo Island, and Point Reyes NS. A detailed description of the proposed activity is presented below:

Southeast Farallon Island

The Southeast Farallon Island is located 28 miles (45 km) offshore of San Francisco, California (37° 41′55″N, 123° 00′10″W). Seabird research activities on the Southeast Farallon Island would involve observational and “hands on” ecological studies of breeding seabirds. Occasionally researchers may travel to coastal areas of the island to conduct observational seabird research where non breeding marine mammals are present. These sorts of tasks include viewing breeding seabirds from an observation blind or censusing shorebirds. This activity usually involves one or two observers. Access to the refuge involves landing in small, 14-18 ft (4.3 - 5.5 m) open motorboats which are hoisted onto the island using a derrick system.

Research on the Southeast Farallon Island would be conducted year round. Most intertidal areas of the island, where pinnipeds are present, would be rarely visited in seabird research. Most potential for incidental take will occur at the island's 2 landings, North Landing and East Landing. These sites would be visited approximately 1 - 3 times per day by researchers. In both locations researchers would not be approaching less than 50 ft (15 m) from any pinnipeds which may be hauled out. Most visits to these areas would be brief (approximately 15 minutes), though seabird observers would be present from 2 - 5 hours daily at North Landing from early April early August to conduct observational studies on breeding Common Murres. Boat landings to re-supply the field station, lasting 1 - 3 hours, would be conducted once every 2 weeks at one of the these locations. Activities involve launching of the boat with one operator, with 2 - 4 other researchers assisting with the operations from land. At East Landing, the primary landing site, all personnel assisting with the landing would stay on the loading platform 30 ft (9 m) above the water. At North Landing, loading operations would occur at the water level in the intertidal.

Ano Nuevo Island

Ano Nuevo Island is located 0.25 mi (0.4 km) offshore of Ano Nuevo Point in San Mateo County, California (37°06′N, 122°20′W). All seabird research work on the Ano Nuevo Island would be in collaborations with Oikonos - Ecosystem Knowledge and through a collaborative agreement with the California State Parks. Procedures include accessing the island by a 12 ft (3.7 m) Zodiac boat. Non-breeding pinnipeds may occasionally be present on the small beach in the center of the island where the boat would be landed. Sea lions may also occasionally be present near a small group of subterranean seabird nest boxes on the island terrace. There are usually 2 - 3 researchers involved in island visits.

Research on the Ano Nuevo Island would be conducted once per week from April to August, and occasional intermittent visits would be made during the rest of the year. A component of the seabird research involves nesting habitat restoration and monitoring, which requires sporadic visits from September to November, between the seabird breeding season and the elephant seal pupping season. Most intertidal areas of the island where marine mammals are present will not be visited during seabird research, excepting the landing beach. Most likely, marine mammal incidental take would occur at this location as well as just north of this beach up on the island's terrace where a small number of seabird nest boxes are located. The landing beach would be visited upon arrival and departure during the weekly visit, and the nest boxes would be checked once on the day of visit. In both locations researchers would not approach less than 50 ft (15 m) away from any pinnipeds which may be hauled out. Landings and visits to nest boxes would be brief (approximately 15 minutes).

Point Reyes National Seashore

Point Reyes NS is located 40 miles (64 km) north of San Francisco Bay, California. The National Park Service (NPS) conducts research, resource management and routine maintenance services at Point Reyes NS. Research along the seashore includes monitoring seabird breeding and roosting colonies. Seabird monitoring usually would involve one or two observers. Surveys Start Printed Page 41296would be conducted in small, 14 - 22 ft (4.3 - 6.7 m) open motorboats that survey along the shoreline. These activities could result in the incidental harassment of pinnipeds. Additionally, NPS would also conduct habitat restoration of the seashore, which would include removal of non-native plants and restoration of coastal dune habitat. Non-native plant removal would be timed to avoid the breeding seasons of pinnipeds, however, on occasion non-breeding animals may be present at various beaches throughout the year.

Description of the Marine Mammals Potentially Affected by the Activity

The marine mammals most likely to be found in the proposed seabird research areas are the California sea lions, Pacific harbor seals, Steller sea lions, and northern elephant seals. General information of these species can be found in Caretta et al. (2007), which is available at the following URL:​pr/​pdfs/​sars/​po2006.pdf. Refer to that document for information on these species. Additional information on these species is presented below.

Northern Elephant Seal

The northern elephant breeding population is distributed from central Baja California, Mexico, to the Point Reyes Peninsula in northern California. Along this coastline there are 13 major breeding colonies. The northern elephant seal was exploited for its oil during the 18th and 19th centuries and by 1900 the population was reduced to 20-30 individuals on Guadalupe Island (Hoelzel et al., 1993; Hoelzel, 1999). As a result of this bottleneck the genetic diversity found in this species is extremely low (Hoelzel, 1999). The recent formation of most rookeries indicates that there is no genetic differentiation among populations. Although movement and genetic exchange occurs among colonies, most seals return to their natal site to breed (Huber et al., 1991). Recolonization of their former breeding range progressed north from the San Benito and Guadalupe Islands off Baja California to the most recent northernmost breeding site at Point Reyes Headlands. In the last three decades, annual pup production has increased at the rate of 9.43 + or −0.51 percent per year in California and 5.19 + or −0.33 percent per year over the entire range (Barlow et al., 1993). A complete population count of elephant seals is not possible because all age classes are not ashore at the same time. Elephant seal population size is usually estimated by counting the number of pups produced and multiplying by the inverse of the expected ratio of pups to total animals (McCann, 1985). Stewart et al. (1994) used McCann's multiplier of 4.5 to extrapolate from 28,164 pups to a population estimate of 127,000 elephant seals in the U.S. and Mexico in 1991. The multiplier of 4.5 was based on a stable population. Boveng (1988) and Barlow et al. (1993) argue that a multiplier of 3.5 is more appropriate for a rapidly growing population such as the California stock of elephant seals. Based on the estimated 28,450 pups born in California and this 3.5 multiplier, the California stock was approximately 101,000 in 2001 (Carretta et al., 2002). At Point Reyes, the population grew at 32.8 percent per year between 1988 and 1997 (Sydeman and Allen, 1999) and around 10 percent per year since 2000 (S. Allen, unpubl. data), and in 2006 around 700 pups were born at three primary breeding areas. The population on the Farallon Islands has declined by 3.4 percent per year since 1983, and in recent years numbers have fluctuated between 100 and 200 pups (W. Sydeman, D. Lee, unpubl. data).

Elephant seals congregate in central California to breed from late November to March. Females typically give birth to a single pup and attend the pup for up to 6 weeks. Breeding occurs after the pup is weaned by attending males. After breeding, seals migrate to the Gulf of Alaska or deeper waters in the eastern Pacific. Adult females and juveniles return to terrestrial colonies to molt in April and May, and males return in June and July to molt, remaining onshore for around 3 weeks.

Pacific Harbor Seal

Harbor seals are one of the most widely distributed northern hemisphere pinnipeds and are found in coastal, estuarine and some times fresh water of both the Atlantic Ocean and Pacific Oceans. There is considerable regional genetic differentiation between harbor seal populations as they are generally limited in migratory movements. Under the MMPA, six stocks of Pacific harbor seals are identified within the U.S. waters (Angliss and Lodge, 2004; Carretta et al., 2006). Only the California stock of harbor seal is found in the proposed project area, and its abundance is estimated to be 34,233 (Carretta et al., 2006). There is some question whether the San Francisco Bay population may be a separate stock based on genetic analyses (D. German, Sonoma State University, pers. com.). At Point Reyes, the harbor seal population is estimated to be 7,524 for the molt season based on a correction factor of 1.65 (Lowry et al., 2005; Manna et al., 2006).

In central California, harbor seals breed annually from March through May and molt in June and July. Females give birth to a single pup and attend the pup for around 30 days, at which time they wean pups. Mating occurs in the water around the time of weaning. Harbor seals are resident year round at terrestrial colonies, however, juveniles may disperse to other colonies ranging up to 500 km (311 mi). Individual adult seals may also migrate widely from breeding colonies.

California Sea Lion

California sea lions range from southern Mexico up to British Columbia and breed almost entirely on islands in southern California, Western Baja California and the Gulf of California. In recent years, California sea lions have begun to breed annually in small numbers at Ano Nuevo Island and South Farallon Island, California. One abandoned pup was found at Point Reyes NS at Wildcat Beach in 2003. This species is separated into three recognized stocks based on three geographic regions (U.S. stock, Western Baja stock, and the Gulf of California stock; Lowry et al. 1992). Some movement has been documented between these geographic stocks, but rookeries in the U.S. are widely separated from major rookeries of western Baja California, Mexico (Barlow et al., 1995). The U.S. stock of California sea lion is the only stock present in the proposed research area. The California sea lion has the largest population of any sea lion species and is the only sea lion whose population is showing a healthy growth rate of 5 to 6.2 percent per annum. Annual incidental takes in fisheries is approximately 915 individuals; however, the population is growing by 8.2 percent per year and fishing mortality is declining (Barlow et al., 1995). Current U.S. population estimates range from 237,000 to 244,000 (Carretta et al., 2007).

California sea lions give birth in May through July and breeding occurs in July and August. Females and pups are resident at breeding colonies year round and males migrate north to feeding areas from central California to British Columbia, Canada. During years of low food availability (e.g., El Nino Southern Oscillation, or ENSO), females and juveniles may also migrate north in search of prey; and in some particularly poor years (1997 - 1998), there can be mass mortality of pups at rookeries.

On the Farallon Islands California sea lions haul out in many intertidal areas year round, fluctuating from several Start Printed Page 41297hundred to several thousand animals. Breeding animals are concentrated in areas where researchers would not visit (PRBO, unpublished data).

California sea lions at Point Reyes haul out at only a couple locations, but will occur on human structures such as boat ramps. The annual population averages around 300 - 500 during the fall through spring months, although on occasion, several thousand sea lions can arrive depending upon local prey resources (S. Allen, unpublished data).

Steller Sea Lion

Steller sea lions breed from the Kuril Islands and Okhotsk Sea through the Aleutian Islands and the Gulf of Alaska, and south to central California (Merrick et al., 1987). Two separate stocks are recognized within U.S. waters: an eastern U.S. stock that includes animals east of Cape Suckling, Alaska (144° W), and a western U.S. stock that includes animals' west of Cape Suckling. In 1990, the Steller sea lion was listed as a threatened species under the Endangered Species Act (ESA), and the western stock was listed as endangered in 1997.

The eastern stock of Steller sea lions breeds on rookeries located in southeast Alaska, British Columbia, Oregon, and California (including the proposed research area). Steller sea lions give birth in May through July and breeding occurs a couple of weeks after birth. Non-reproductive animals congregate at a few haul out sites, including at Ano Nuevo and Point Reyes Headland. Pups are weaned during the winter and spring of the following year. On the Farallon and Ano Nuevo Islands, Steller sea lion breeding colonies are located in closed areas where researchers never visited, eliminating any risk of disturbing breeding animals.

Count of pups on rookeries conducted near the end of the birthing season are nearly complete counts of pup production. Using the most recent 2005 pup counts available by region from aerial surveys across the range of the eastern stock, the total population of the eastern stock of Steller sea lions is estimated to be 47,885. This is based on multiplying the total number of pups counted in southeast Alaska (5,519), British Columbia (3,281), Oregon (1,128), and California (713) by 4.5 (Angliss and Outlaw, 2007). Because the eastern stock of Steller sea lions is increasing within most of its range, using the 4.5 multiplier is a reasonable approach to estimating abundance from pup counts (Angliss and Outlaw, 2007).

Steller sea lion numbers in California, especially in southern and central California, have declined from historic numbers. Counts in California between 1927 and 1947 ranged between 5,000 and 7,000 non-pups with no apparent trend, but have subsequently declined by over 50 percent, remaining between 1,500 and 2,000 non-pups during 1980-2001. Limited information suggests that counts in northern California appear to be stable (NMFS, 1995). At Ano Nuevo Island, a steady decline in ground counts started around 1970, resulting in an 85 percent reduction in the breeding population by 1987 (LeBoeuf et al., 1991). In vertical aerial photographic counts conducted at Ano Nuevo, pups declined at a rate of 9.9 percent from 1990 to 1993, while non-pups declined at a rate of 31.5 percent over the same time period (Westlake et al., 1997). Pup counts at Ano Nuevo have been steadily declining at about 5 percent annually since 1990 (W. Perryman, NMFS-SWFSC, pers. comm.). On Southeast Farallon Island, the abundance of Steller sea lion females declined an average of 3.6 percent per year from 1974 to 1997 (Sydeman and Allen, 1999). Pup counts on the Farallon Islands have generally varied from 5 - 15 (Hastings and Sydeman, 2002,; PRBO unpublished data). The most recent pup counts at Ano Nuevo Island and the Farallones are 349 in 2000 and 287 in 2001 (M. Lowry, NMFS-SWFSC, pers. comm.). Pups have not been born at Point Reyes Headland since the 1970s and Steller sea lions are seen in very low numbers there currently (S. Allen, unpubl. data).

Potential Effects on Marine Mammals and Their Habitat

The only anticipated impacts would be temporary disturbances caused by the appearance of researchers near the pinnipeds. The potential disturbance might alter pinniped behavior and cause animals to flush from the area. Animals may return to the same site once researchers have left or go to an alternate haul out site, which usually occurs within 30 minutes (Allen et al., 1985). Long term effects of this disturbance are unlikely, as very few breeding animals will be present in the vicinity of the proposed seabird research areas. The proposed seabird research would not result in the physical altering of marine mammal habitat. No marine mammal habitat is expected to be affected by the proposed action. No marine mammal critical habitat is found within the proposed research area.

There is no subsistence harvest of marine mammals in the proposed research area, therefore, there will be no impact of the activity on the availability of the species or stocks of marine mammals for subsistence uses.

Number of Marine Mammals Expected to Be Taken

It is expected that approximately 2,422 California sea lions, 500 harbor seals, 273 northern elephant seals, and 14 Steller sea lions could be potentially affected by Level B harassment. This estimate is based on previous research experiences, with the same activities conducted in the proposed research area, and on marine mammal research activities in these areas. These incidental harassment take numbers represent approximately 1 percent of the U.S. stock of California sea lion, 1.5 percent of the California stock of Pacific harbor seal, 0.3 percent of the California breeding stock of northern elephant seal, and 0.03 percent of the eastern U.S. stock of Steller sea lion. All of the potential takes are expected to be Level B behavioral harassment only. No injury or mortality to pinnipeds is expected or requested.

Mitigation, Monitoring, and Reporting

The researchers would take all possible measures to reduce marine mammal disturbance for the activities described above. Researchers would keep their voices hushed and bodies low in the visual presence of pinnipeds. Seabird observations at North Landing on Southeast Farallon Island would be conducted in an observation blind where researchers are shielded from the view of hauled out pinnipeds. Beach landings on Ano Nuevo Island would only occur after any pinnipeds that might be present on the landing beach have entered the water. Ano Nuevo Island researchers accessing seabird nest boxes would crawl slowly if pinnipeds are within view.

Visits to intertidal areas of Southeast Farallon Island during research activities would be coordinated to reduce potential take. All research goals on Ano Nuevo Island would be coordinated to minimize the necessary number of trips to the island. Once on Ano Nuevo Island, researchers would coordinate monitoring schedules so areas near any pinnipeds would be accessed only once per visit. The lead biologist would always serve as an observer to evaluate incidental take and halt any research activities should the potential for incidental take be too great.

Researchers would take notes of sea lions and seals observed within the proposed research area during studies. The notes would provide dates, time, tidal height, species, numbers of sea lions and seals present, and any disturbances. PRBO would submit a final report, including these notes, to Start Printed Page 41298NMFS within 90 days after the expiration of the IHA, if it is issued.

National Environmental Policy Act (NEPA)

NMFS has prepared a draft EA for public review and comment (see ADDRESSES), that describes the impact on the human environment that would result from implementation of this action. NMFS has concluded, preliminarily, that no significant impact on the human environment would result.


NMFS is conducting a Section 7 consultation under the ESA to make a determination whether the proposed research project would be likely to jeopardize the continued existence of the eastern U.S. stock of Steller sea lions.

Preliminary Determinations

For the reasons discussed in this document and in the identified supporting documents, NMFS has preliminarily determined that the impact of seabird research on Southeast Farallon Island, Ano Nuevo Island, and Point Reyes NS would result, at worst, in the Level B harassment of small numbers of California sea lions, Pacific harbor seals, northern elephant seals, and Steller sea lions hauled out in the vicinity of the proposed research area. While behavioral modifications, including temporarily vacating the area during the survey period, may be made by these species to avoid the resultant visual disturbance, the availability of alternate areas within these areas and haul-out sites has led NMFS to preliminarily determine that this action will have a negligible impact on California sea lions, Pacific harbor seals, northern elephant seals, and Steller sea lions.

In addition, no take by Level A harassment (injury) or death is anticipated and harassment takes should be at the lowest level practicable due to incorporation of the mitigation measures described in this document.

Proposed Authorization

NMFS proposes to issue an IHA to PRBO for the potential harassment of small numbers of California sea lions, harbor seals, northern elephant seals, and Steller sea lions incidental to conducting of seabird research on Southeast Farallon Island, Ano Nuevo Island, and Point Reyes NS, provided the previously mentioned mitigation, monitoring, and reporting requirements are incorporated.

NMFS requests interested persons to submit comments, information, and suggestions concerning this request (see ADDRESSES).

Start Signature

Dated: July 23, 2007.

Helen Golde,

Deputy Director, Office of Protected Resources, National Marine Fisheries Service.

End Signature End Supplemental Information

[FR Doc. E7-14584 Filed 7-26-07; 8:45 am]