ACS Public Policies

POLICY

The American Cetacean Society (ACS) supports the listing of the Eastern North Pacific (ENP) southern resident killer whale population (J, K, and L pods) as a threatened or endangered species under the U.S. Endangered Species Act (ESA) of 1973, as amended. Further, ACS supports measures for conservation, education and research regarding the habitat of this genetically distinct population of killer whales. (Notably, per section 3(15) of the ESA the term "species" includes any subspecies, and any distinct population segment of any species which interbreeds when mature.)

The National Marine Fisheries Service (NMFS) would evaluate whether the ENP southern resident killer whale population should be listed as threatened or endangered once a petition for listing is filed. Per section 3 of the ESA, an endangered species is defined as any species in danger of extinction throughout all or a significant portion of its range. A threatened species is defined as any species likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range. A proposed species is defined as a species that has been proposed for listing as endangered or threatened, for which a final determination of status is to be completed within 12 months.

BACKGROUND:

Elevated concern for the ENP southern resident killer whale population has recently been expressed in a number of publications, as well as at an April 2000 southern resident killer whale workshop held at the National Marine Mammal Laboratory of the NMFS (Dahlheim et al. 2000). In addition, this population of killer whales was recently listed as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). (COSEWIC is comprised of various federal and provincial Canadian agencies, as well as non-profit groups). The primary factors that have led to elevated concern for this killer whale population are summarized briefly below for the purpose of providing background information in support of this ACS policy.

Killer whales in the inland waters of Washington State and southern British Columbia have been intensively studied using photo-identification techniques since the mid-1970s; this research has provided substantial understanding of the whale's stock structure, behaviors and movements (e.g., Ford et al. 1994, Barlow et al. 1997). Based on photo-identification studies as of October 1999, including identification of dead individual whales, the ENP southern resident killer whale population has decreased by more than 15 percent over the last four years (1995 to 1999), from 98 to 83 whales (Dahlheim et al. 2000). This decrease may be due to an increased death rate (van Ginneken and Ellifrit 1998, Baird 1999). This loss of 16 individuals over the last four years (i.e., average of 4 animals/year) is more than double the "potential biological removal" (1.9 animals per year) identified by the NMFS as the allowable take that, combined with known natural mortality, ensures that the stock is not reduced below its optimum sustainable population level (Barlow et al. 1997).

Studies indicate that, based on mitochondrial and other DNA tests, the ENP southern resident killer whales are genetically distinct from the transients and northern residents of the ENP and are considered a separate population by the NMFS for management purposes (Barlow et al. 1997, Hoelzel et al. 1998). ACS believes that continued decreases in the population numbers may increase the vulnerability of the population to disease and reduce the gene pool of the population.

Per Section 4 of the ESA, the Secretary of Commerce shall determine whether any species (under the jurisdiction of the NMFS) is an endangered or threatened species based on any one of the following factors: (a) the present or threatened destruction, modification, or curtailment of its habitat or range; (b) over-utilization for commercial, recreational, scientific, or educational purposes; (c) disease or predation; (d) the inadequacy of existing regulatory mechanisms; or (e) other manmade factors affecting its continued existence. ACS believes that items (a), (c), and (e) of Section 4 of the ESA warrant listing of the ENP southern resident population of killer whales as threatened or endangered as summarized below.

ESA Section 4, Item a (Habitat):

Currently, 26 evolutionarily significant units (ESUs) of salmonids inhabiting the Pacific coast of the U.S. are listed as threatened or endangered under the ESA, 1 ESU is proposed for listing, and 6 ESUs are candidates for listing (NMFS website, June 2000). (A PDF file of this report can be downloaded from the NMFS website.) These include the threatened Puget Sound chinook salmon and the threatened Hood Canal chum salmon inhabiting Puget Sound where these killer whales are known to reside. Salmon are the preferred prey of this population of killer whales (Ford et al. 1994, 1998). There is also evidence of killer whales being opportunistic feeders and preying upon a variety of fish species, including rockfish and other bottom fish and possibly herring (Baird et al. 1999, Ford et al. 1998). Other fish species inhabiting the range of these whales and being considered for listing as endangered or threatened species under the ESA are the Pacific herring, Pacific cod, Pacific hake, walleye pollock, and brown, copper, and quillback rockfish.

ESA Section 4 (Item c) (Disease):

The ENP southern resident killer whale population has been shown to have very high (up to 146 parts per million) levels of PCBs (Ross et al. 2000). Studies indicate that high levels of these toxic chemicals impair the reproduction and immune systems of marine mammals (Ross et al. 1996). Ross et al. (2000) found that the ENP southern resident population of killer whales is 2 to 3 times more contaminated with PCBs than the St.Lawrence beluga whale population. Fairly solid evidence exists that contaminants have adversely affected reproduction in this population of belugas, led to tumors (45% of all tumors ever found in cetaceans world-wide have been described in the St. Lawrence belugas, where the population is only 500-700 animals), and played a role in disease through immunosuppression (De Guise et al. 1995, Ross et al. 1996).

ESA Section 4 (Item e) (Manmade Factors):

A number of manmade factors have been identified as sources of potential concern with respect to the continued existence of the ENP southern resident killer whale population (Bain and Balcomb 1999, Baird 1999, Dahlheim et al. 2000). For example, heavy commercial and private vessel traffic has been identified as a potential stressor to this population (Baird 1999, Dalheim et al. 2000, Trites and Bain 2000). In addition, a large number of oil tankers occur in Haro Strait. The impact of an Exxon Valdez scale event would be especially devastating to a small population such as the ENP southern resident killer whales (pers. comm., D. Bain, Six Flags Marine World, Vallejo, CA, May 2000).

LITERATURE CITED

Bain, D.E. and K.C. Balcomb. 1999. Population Trends of Southern Resident Killer Whales (Orcinus orca) from 1960-1999. Unpublished Report Submitted to the November 1999 Scientific Review Group Meeting, Maui, HI.

Baird, R.W. 1999. Status of Killer Whales in Canada. Species Status Report: Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Ottawa.

Barlow, J., K.A. Forney, P.S. Hill, R.L. Brownell, Jr., J.V. Carretta, D.P. DeMaster, F. Julian, M.S. Lowry, T. Ragen, and R.R. Reeves. 1997. U.S. Pacific Marine Mammal Stock Assessments: 1996. U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries Science Center, La Jolla, CA. NOAA Technical Memorandum NOAA-TM-NMFS-SWFSC-248.

Dahlheim, M., D. Bain, D. DeMaster, and C. Sims. 2000. Proceedings from the Southern Resident Killer Whale Workshop, National Marine Mammal Laboratory, National Marine Fisheries Service, Seattle, WA, 1-2 April 2000. Available from the National Marine Mammal Laboratory, National Marine Fisheries Service, Seattle, WA.

De Guise, S., D. Martineau, P. Beland, and M. Fournier. 1995. Possible Mechanisms of Action of Environmental Contaminants on St. Lawrence Beluga Whales (Delphinapterus leucas). Environmental Health Perspectives Supplements 103:73-77.

Ford, J.K., G.M. Ellis, and K.C. Balcomb. 1994. Killer Whales. University of Washington Press, Seattle, WA, and University of British Columbia Press, University of British Columbia, Vancouver, British Columbia.

Ford, J.K., G.M. Ellis, L.G. Barrett-Lennard, A. Morton, R. Palm, and K.C. Balcomb III. 1998. Dietary Specialization in Two Sympatric Populations of Killer Whales (Orcinus orca) in Coastal British Columbia and Adjacent Waters. Canadian Journal of Zoology 76:1456-1471.

Hoelzel, A.R., M. Dahlheim, and S. J. Stern. 1998. Low Genetic Variation Among Killer Whales (Orcinus orca) in the Eastern North Pacific and Genetic Differentiation Between Foraging Specialists. Journal of Heredity 89(2):121-128.

Ross, P.S., R. De Swart, R. Addison, H. van Loveren, J. Vos, and A. Osterhaus. 1996. Contaminant-induced Immunotoxicity in Harbor Seals: Wildlife at Risk? Toxicology 112:157-169.

Ross, P.S., G.M. Ellis, M.G. Ikonomou, L.G. Barrett-Lennard, and R.F. Addison. 2000. High PCB Concentrations in Free-Ranging Pacific Killer Whales, Orcinus orca: Effects of Age, Sex, and Dietary Preferences. Marine Pollution Bulletin 40(6):504-515.

Trites, A. W. and D. E. Bain. 2000. Short- and Long-term Effects of Whalewatching on Killer Whales (Orcinus orca) in British Columbia. Unpublished manuscript. Marine Mammal Research Centre, University of British Columbia, Vancouver, British Columbia.

Van Ginneken, A.M. and D.K. Ellifrit. 1998. Orca Survey: Field Guide to Orcas of the Pacific Northwest--the Southern Resident Community. Center for Whale Research, Friday Harbor, WA.