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Estimating the harvest of Pacific walrus, Odobenus rosmarus divergens, in Alaska

01/1999;

ABSTRACT for J. L. Garlich-Miller): Joel_GarlichMiller@mail.fws.gov Manuscript accepted 13 January 1999 Fish. Bull. 97(4):1043–1046 (1999). For thousands of years, walrus hunting has been an important component of the economy and cul-ture of Native communities along the Bering and Chukchi Sea coasts (Ray, 1975). Today, the Pacific wal-rus (Odobenus rosmarus divergens) remains a valuable resource to coastal natives in Alaska (United States) and Chukotka (Russia) as a source of food and raw materials for traditional equipment and handicrafts. Accurate information regarding the number of animals removed annually from the population is fundamental for the conservation and management of any species. As the agency responsible for manag-ing Pacific walrus in U.S. waters, the U.S. Fish and Wildlife Service (FWS) gathers data on the size and composition of the subsistence wal-rus harvest in Alaska. The FWS presently administers two separate harvest monitoring programs: the Walrus Harvest Monitoring Project (WHMP) and the Marking Tagging and Reporting Program (MTRP). The WHMP is an observer pro-gram carried out at select walrus hunting villages in Alaska. Each spring, as the pack ice recedes northward, hunters from coastal communities in the Bering Strait region have access to herds of wal-rus as they migrate to their sum-mer range. Historical harvest infor-mation indicates that approxi-mately 80% of the annual reported walrus harvest in Alaska occurs in this region (Fay and Bowlby 1). WHMP monitors stationed at the primary walrus hunting villages in the Bering Strait region (Gambell, Savoonga, Little Diomede and Wales; Fig. 1) collect information on the size and composition of the wal-rus harvest. Harvest monitors meet boats as they return from walrus hunting trips in order to collect bio-logical samples and harvest infor-mation at the boat landing site (Garlich-Miller 2). The goal of the WHMP is to identify and record the gender and age class of every wal-rus retrieved by hunters from these villages during the monitoring pe-riod. Although there is no way of evaluating the degree to which this goal is achieved, WHMP monitors meet most of the returning boats, and the number of retrieved ani-mals not recorded during the har-vest monitoring period is believed to be small (Dickerson 3). The MTRP is a Federally man-dated year-round, statewide pro-gram (Fig. 1). The marking and tag-ging rule requires that all hunters certify (tag) walrus ivory (tusks) and report all walruses that are taken. The objectives of the MTRP are to collect harvest information and to certify specified marine mammal parts to help control ille-gal harvests and trade. Hunters are required to bring walrus tusks to a MTRP tagger within 30 days of the kill. The tagger attaches individu-ally numbered wire tags to the tusks and records the numbers on a tagging certificate. MTRP tags are not attached to calf walruses (or other walruses that may be miss-ing tusks); however, hunters are required to report all animals taken. The age class, gender, kill date, and kill location of each wal-rus are recorded on the certificate (Stephensen et al. 4). These two programs indepen-dently provide information on the size and composition of the harvest. Except in the case of the village of Wales, WHMP and MTRP staff are different people. Each of the two monitoring programs has its strengths and weaknesses. The WHMP benefits from the presence of on-site staff to collect accurate biological information from every walrus retrieved in a community during the monitoring period. Un-fortunately, the monitoring period is seasonal (restricted to the spring hunt) and operates only in four coastal villages. The MTRP is a statewide, year-round program; however hunter compliance with the MTRP rule is variable and ani-mals lacking tusks (e.g. calves, yearlings, and animals with broken tusks) often go unreported (Burn, 1998).

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