Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To Delist the Southern Sea Otter (Enhydra lutris nereis

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Notice of 90-day petition finding.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), announce a 90-day finding for a petition to remove the southern sea otter (Enhydra lutris nereis), throughout its range, from the Federal List of Endangered and Threatened Wildlife, pursuant to the Endangered Species Act of 1973, as amended (ESA) (16 U.S.C. 1531 et seq.). We reviewed the petition and supporting documentation, information in our files, and other available information, and find that there is not substantial information indicating that delisting of the southern sea otter may be warranted. We will not be initiating a further status review in response to the petition to delist. We ask the public to submit to us any new information that becomes available concerning the status of this species. This information will help us monitor and promote the conservation of this species.

DATES:

The finding announced in this document was made on November 14, 2003. You may submit new information concerning this species for our consideration at anytime.

ADDRESSES:

Data, information, written comments and materials, or questions concerning this petition and finding should be submitted to the Field Supervisor, U.S. Fish and Wildlife Service, Ventura Fish and Wildlife Office, 2493 Portola Road, Suite B, Ventura, California 93003. The petition finding and supporting data are available for public inspection, by appointment, during normal business hours at the above Ventura address.

FOR FURTHER INFORMATION CONTACT:

Lilian Carswell, Biologist, Southern Sea Otter Recovery Program, at the above Ventura address, or telephone 805-644-1766.

SUPPLEMENTARY INFORMATION:

Background

We listed the southern sea otter as a threatened species in 1977 (42 FR 2968; January 14, 1977) because of its small population size, its limited distribution, and potential risk to its habitat and population from oil spills. Critical habitat was not proposed. We approved the first recovery plan for the southern sea otter in 1982, and we published a final revised recovery plan in 2003 (Service 2003).

Because the southern sea otter is listed as a threatened species, it is also recognized as depleted under the Marine Mammal Protection Act of 1972, as amended (16 U.S.C. 1361-1407). Under the Marine Mammal Protection Act, Federal agencies are charged with managing marine mammals to their optimum sustainable population level. The estimated optimum sustainable population level for southern sea otters is greater than that required for delisting consideration under the ESA. We estimate that the lower limit of the optimum sustainable population level for the southern sea otter is approximately 8,400 animals (Service 2003).

The petition to delist the southern sea otter under the ESA, dated July 30, 1998, was submitted by Nancy E. Gregg to the National Marine Fisheries Service along with four petitions to delist other marine mammal species under the ESA: the California sea lion (Zalophus californianus), the Pacific harbor seal (Phoca vitulina), the polar bear (Ursus maritimus), and the Pacific walrus (Odobenus rosmarus divergens). Although these four species are protected by the Marine Mammal Protection Act, they are not currently listed under the ESA and consequently cannot be considered for delisting. The southern sea otter is a listed species under the ESA and is under the jurisdiction of the Service. Therefore, the National Marine Fisheries Service forwarded the petition to delist the southern sea otter to us. The petition, which we received on May 13, 1999, requested that we remove the southern sea otter from the List of Endangered and Threatened Wildlife and Plants.

Section 4(b)(3)(A) of the ESA requires that we make a finding on whether a petition to list, delist, or reclassify a species presents substantial scientific or commercial information indicating that the petitioned action may be warranted. We base the finding on information in the petition and its supporting documentation, information in our files, and other information available to us at the time the finding is made. To the maximum extent practicable, we make this finding within 90 days of receipt of the petition and promptly publish notice of the finding in the Federal Register. If we find that substantial information was presented, we are required to commence a review of the status of the species promptly, if one has not already been initiated (50 CFR 424.14).

The factors for listing, delisting, or reclassifying species are described at 50 CFR 424.11. We may delist a species only if the best scientific and commercial data available substantiate that it is neither endangered nor threatened for one or more of the following reasons: (1) Extinction; (2) recovery; and/or (3) a determination that the original data used for classification of the species as endangered or threatened were in error.

In response to the petitioner's request to delist the southern sea otter, we sent a letter to the petitioner on June 8, 1999, acknowledging our receipt of the petition. We were unable to act upon the petition due to the low priority assigned to delisting petitions in accordance with our Listing Priority Guidance for Fiscal Years 1998 through 1999, which was published in the Federal Register on May 8, 1998 (63 FR 25502). Since 1999, higher priority work has not allowed us to examine or to act upon the petition to delist the southern sea otter.

Discussion

The petition offers no information on the population trends or status of the southern sea otter to support the proposed administrative action. Much of the material offered in support of the petition to delist the southern sea otter refers to pinnipeds (seals, sea lions, and walruses), marine mammals in general, or the Marine Mammal Protection Act. The petition mentions sea otters only in passing, in a quote from the April 7, 1981, testimony of C. Dale Snow, who testified on behalf of the Oregon Department of Fish and Wildlife before the Subcommittee on Fisheries and Wildlife Conservation and the Environment of the House Committee on Fisheries and Wildlife. Mr. Snow's testimony was given in the context of congressional hearings on the reauthorization of the Marine Mammal Protection Act. The excerpted testimony reads as follows: “(6) Seals, Sea Lions, Polar Bears, Walrus, and Sea Otters: If these animals were removed from the [Marine Mammal Protection] Act, it might solve Oregon's problems, and probably those of several other states. The Act would still afford the desired protection for whales and manatees and yet allow management of a valuable natural resource.” Although the petitioner included the full text of this testimony with the petition as supporting documentation, this remark constitutes its sole mention of sea otters.

Mr. Snow's testimony relates primarily to the management of marine mammals in Oregon under the Marine Mammal Protection Act and focuses specifically on pinnipeds and salmon (Oncorhynchus spp.) in Oregon. It does not provide any information about the status of southern sea otters. Southern sea otters do not currently occur in northern California or Oregon. Historically, southern sea otters ranged from about mid-Baja California, Mexico, to at least northern California (Wilson et al. 1991), and possibly as far north as Prince William Sound in Alaska (reviewed in Riedman and Estes 1990). Currently, however, southern sea otters occur only in central and southern California. The mainland range of the southern sea otter extends from about Point Conception, Santa Barbara County, to Half Moon Bay, San Mateo County. A small experimental colony of southern sea otters also exists at San Nicolas Island, Ventura County.

The petition does not provide a narrative justification for delisting the southern sea otter under the ESA. We infer that the petitioner advocates delisting the southern sea otter in the belief that it would allow for the control of predation on anadromous salmonids. In addition to the congressional testimony of Mr. Snow, the petitioner cites as supporting information two reports concerning anadromous salmonids. The petitioner states: “These reports clearly show that the Federal government's failure to delist these species is the reason for the endangerment of the west coast salmon.”

We have no information to indicate that southern sea otters are implicated in the decline of anadromous salmonids as the petitioner suggests. Southern sea otters are not known predators of anadromous salmonids. The diet of southern sea otters is composed almost entirely of nearshore invertebrates (Riedman and Estes 1990). Although sea otters of the subspecies Enhydra lutris lutris and E. l. kenyoni consume fishes as well as invertebrates in areas of their range in Russia and Alaska, predation on fishes in California, where the southern sea otter occurs, is extremely rare (reviewed in Riedman and Estes 1990).

Regardless, the effects of predation by a listed species are not a relevant consideration in determining whether a species should be considered for delisting under the ESA. As noted above, we may delist a species only if the best scientific and commercial data available substantiate that it is neither endangered nor threatened. The petitioner provided no scientific or commercial data to substantiate that the southern sea otter is extinct, has recovered, or that the original data used to classify the southern sea otter as threatened were in error.

Information in our files, and other information available to us, does not support a finding that delisting of the southern sea otter should be considered at this time. We recently published a final revised recovery plan for the southern sea otter (Service 2003), which reviews the current status of the species. Continuing threats to the southern sea otter include disease, exposure to environmental contaminants, intentional take (shooting), and potential entanglement in fishing gear. Oil spills, which could occur at any time, threaten the southern sea otter with catastrophic decimation or localized extinction (Service 2003). The recovery plan gives recovery criteria for the southern sea otter and states that the species will be considered for delisting under the ESA when the average population level over a 3-year period exceeds 3,090 animals. The most recent spring survey recorded 2,505 southern sea otters (U.S. Geological Survey, unpublished data), and the latest available 3-year running average (for 2002) is only 2,268 animals.

Finding

We have reviewed the petition and its supporting documentation, information in our files, and other available information. We find that there is not substantial information indicating that delisting of the southern sea otter may be warranted.

Information Solicited

When we find that there is not substantial information indicating that the petitioned action may be warranted, initiation of a status review is not required by the ESA. However, we regularly assess the status of species listed as threatened or endangered and welcome any information concerning the status of the southern sea otter. You may submit any information at any time to the Field Supervisor, Ventura Fish and Wildlife Office (see ADDRESSES).

References Cited

Riedman, M.L. and J.A. Estes. 1990. The sea otter (Enhydra lutris): behavior, ecology, and natural history. U.S. Fish and Wildlife Service, Biol. Rep. 90(14). 126 pp.

U.S. Fish and Wildlife Service. 2003. Final Revised Recovery Plan for the Southern Sea Otter (Enhydra lutris nereis). Portland, Oregon. xi + 165 pp.

U.S. Geological Survey, Biological Resources Division. 2003. Spring 2003 mainland California sea otter survey results. Memorandum from B. Hatfield dated 9 June 2003.

Wilson, D. E., M. A. Bogan, R. L. Brownell, Jr., A. M. Burdin, and M. K. Maminov. 1991. Geographic variation in sea otters, Enhydra lutris. J. Mamm., 72(1):22-36.

Author

The primary author of this document is Lilian Carswell, Fish and Wildlife Biologist, U.S. Fish and Wildlife Service, Ventura Fish and Wildlife Office (see ADDRESSES section).

Authority: The authority for this action is the Endangered Species Act of 1973 as amended (16 U.S.C. 1531 et seq.).