KODIAK (AP) -- A survey conducted this summer indicates that Kodiak's otter population is down 40 percent.
Angie Doroff of the U.S. Fish and Wildlife Service said the agency is still seeking supplemental information before the results are finalized. But she expects adjustments to the overall estimate to be slight.
The magnitude of the decline is worrisome, Doroff said.
The Kodiak survey was part of an effort to determine the eastern extent of sea otter declines. Surveys in the Aleutian Islands last year show otter populations in that area have dropped 70 to 90 percent since the 1970s.
Kodiak sea otters are primarily descendents of a group of otters from Shuyak Island that survived massive fur-trade hunts in the 19th century. Most otters in the Kodiak archipelago live around Shuyak and Afognak Islands and in Marmot and Chiniak Bays. Small populations also are scattered around most of Kodiak Island.
Doroff said she had hoped to see Kodiak otters colonizing more areas, in keeping with the historical population expansion.
Fish and Wildlife is waiting for results from surveys in the Cook Inlet area to help determine if those populations also are declining.
''Our primary goal with our work right now is to identify the scope of the problem,'' Doroff said.
Otter populations in Prince William Sound are known to be stable, Doroff said. The population in that area has been surveyed regularly since the Exxon Valdez oil spill.
Theories for the cause of the sea otter decline in Western Alaska include killer whale and shark predation.
''What we're seeing is fairly consistent with that hypothesis,'' Doroff said. ''We continue to get incidental reports from fishermen and other (people) where they've seen killer whales interacting with sea otters and sometimes killing them.''
But the link between predation and otter declines is not simple to establish. Many of the sea otter/killer whale interactions have been reported from Prince William Sound, where the otter population is healthy.
What's more, the Sound has a huge shark population. While the Kodiak population drop is disturbing, it is not nearly as distressing as the drop in the Western region, Doroff said.
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