Pacific Walrus Monitoring

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The U.S. Fish and Wildlife Service has management authority for three species of marine mammals in Alaska: Pacific walrus, polar bears, and sea otters. This management authority came from the Marine Mammal Protection Act of 1972. The USFWS Marine Mammals Management Office currently manages Pacific walrus in Alaska. The Togiak National Wildlife Refuge's walrus monitoring program focuses on monitoring the abundance and distribution of Pacific Walrus at selected haulouts at Cape Peirce and Cape Newenham. 2006 Marine Mammal Report (PDF 1.17MB)

Togiak Refuge's rocky coast and sand beaches support a diverse and abundant marine mammal population. Cape Peirce and Cape Newenham are particularly rich in marine mammals, providing haulout areas for Pacific walrus, harbor seals, spotted seals, and Steller sea lions.

Cape Peirce is one of the two largest regularly used terrestrial haulouts for Pacific walrus in the United States. Other terrestrial haulouts in southwest Alaska include Cape Newenham, Cape Seniavin and Round Island. The female and young walrus that winter in and near Bristol Bay and Kuskokwin Bay migrate north in the spring, however, some of the males remain behind.

Cape Peirce was historically used as a haulout but was abandoned sometime during the first half of the 20th century. Walrus began reusing the haulouts in 1981 and have returned every summer since. The Togiak National Wildlife Refuge, U.S. Fish and Wildlife Service's Marine Mammals Management, the Alaska Department of Fish and Game, and Bristol Bay Native Association work jointly to determine the abundance and distribution of walrus in northern Bristol Bay. A continued cooperative effort will help ensure responsible management of this species.

In addition to the cooperative monitoring efforts, the U.S. Geological Survey's Biological Resources Division (BRD) has been studying walrus movement and feeding patterns in Bristol Bay. BRD staff have based out of the Cape Peirce field camp to attach satellite radio transmitters on walrus for this research effort. [LINK THAT FOLLOWS HAS MOVED!]  Learn more about BRD's Pacifc walrus research programs.

The Togiak Refuge walrus monitoring program works to:

  • estimate number of walrus daily from spring to fall at Cape Peirce;
  • estimate number of walrus daily from late June to late July at Cape Newenham;
  • document walrus behavioral response to aircraft, boats, research and visitor use at Cape Peirce and Cape Newenham;
  • provide support for other organizations conducting marine mammal research.

Cape Peirce: 

Walrus haulouts at Cape Peirce have been censussed from the ground from May to September since 1981. The annual peak number of walrus hauled out during a single day has ranged from 284 to 12,500 walrus, with the peak numbers occurring between June 10 and October 6. The timing of peaks may be related to males migrating north in the fall to join females at the edge of the ice pack.

The number of walrus using the Cape Peirce haulout increased during the years 1981 to 1985, when the high count of 12,500 walrus was recorded. Walrus numbers at the haulouts at Cape Peirce generally declined from 1986-1990 and have been rising, but variable, in the ensuing years. Beginning with 1989, a pattern appears of alternating higher and lower peak counts from year to year. The Pacific walrus population as a whole has remained stable throughout this time.

Within individual years, strong fluctuations in numbers of walrus onshore occur during the census period at Cape Peirce. Telemery studies suggest that these variations may be synchronous with resting and feeding cycles. Such differences in numbers may also be related to severity of storms and to human disturbances. During storms with strong onshore winds and heavy surf, hauling grounds are usually abandoned.

There are five walrus haulouts at Cape Peirce: Odobenus Cove, South Firebaugh, North Firebaugh, Parlier Beach, and Maggy Beach. From field observations it seems that when walrus arrive at Cape Peirce, they begin using Odobenus Cove, South Firebaugh, and North Firebaugh. These beaches are protected from potential predators by high, rocky cliffs. When these beaches "fill up" they begin using Maggy Beach, a large, sandy, exposed beach. A greater number of walrus can haulout at Maggy Beach than all other beaches combined.

Each year, disturbances to walrus at the Cape Peirce haulouts occur. People, aircraft, boats, and unknown factors cause these disturbances. Walrus may leave their haulouts or otherwise alter their behavior when disturbed. Staff record disturbances and the observed effects on walrus.

Cape Newenham: 

Walrus haulouts at Cape Newenham have been censussed from the ground from April to December since 1986. The annual peak number of walrus hauled out during a single day has ranged from 4 to 5,444 walrus, and has occurred between June 30 and July 21.

Walrus haulouts at Cape Newenham were monitored daily throughout the summer season in 1991-1993, 1996, and 1997. From 1998-2003, the walrus haulouts were monitored only from late June to late July as part of a cooperative Bristol Bay walrus monitoring program. Beginning in 2004, the haulouts were monitored by aerial survey on a weekly or bi-weekly schedule.

The beaches at Cape Newenham have been used sporadically by walrus during the last 10 years. From 1978 to 1984, when observations were very irregular, walrus numbers ranging from a few individuals to several thousand animals were reported. Between 1988 and 1990 few walrus were seen at Cape Newenham. In the 4 years of regular censuring (1991-1993 and 1996), annual peaks ranged from 870 to 5,444.

For more information regarding Pacific Walrus, contact the Togiak National Wildlife Refuge.