Walrus feeding: a re-examination

• Main Author: Sheffield, Gay Glover
• Format: Thesis
• Language: English
• Published: 1997
• Subjects: Walrus; Diet; Chukchi Sea; Bering Sea; Fairbanks; Pacific; Chukchi; Odobenus rosmarus; Alaska; walrus*
• Online Access: http://hdl.handle.net/11122/14805

Thesis (M.S.) University of Alaska Fairbanks, 1997 A new approach for analyzing walrus (Odobenus rosmarus) diet was examined. Controlled gastric digestion experiments determined the relative rates at which different kinds of food items became unidentifiable. The ability to identify prey items varied within and among prey types. The laboratory experiments provided a new basis for examining diet data by characterizing the condition of stomach samples based on the rates at which different prey types were digested. Stomach content data acquired during 1952-1991 from 798 Pacific walruses were compiled, and interpretations about feeding habits were re-examined. Walruses regularly consumed a wider assortment of benthic prey than was previously thought. The diet of the Pacific walrus varied seasonally and regionally. Males and females consumed essentially the same food items when in the same location. Biological Resources Division of the U.S. Geological Survey, the Marine Mammals Management office of the U.S. Fish and Wildlife Service