Abstract: Under conditions of rapid sea-ice retreat and dissolution, we observed at least nine Pacific walrus calves separated from adult females in waters as deep as 3,000 m in July and August 2004 in the Canada Basin of the Arctic Ocean. Given limited sea surface visibility from the ship, we surmise that many additional calves may have been separated in the overall study area. These conditions appear to have been related to the transport of unusually warm (7° C) Bering Sea water into this area north of Alaska. Walruses invest considerable maternal resources while caring for calves on seasonally ice-covered continental shelves for periods of up to 2 y or more and only rarely separate from their young. Therefore, these observations indicate that the Pacific walrus population may be ill-adapted to rapid seasonal sea-ice retreat off Arctic continental shelves.

Key Words: Pacific walrus, Odobenus rosmarus divergens, marine mammal strandings, marine mammal recruitment, global warming, Arctic, sea-ice, Chukchi Sea, Beaufort Sea

Document Type: Research article

DOI: 10.1578/AM.32.1.2006.98

Page Numbers: 98-102

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