4/21/2012 12:39:28 PM
Mysterious Skin Disease Affects Alaskan Polar Bears
Scientists with the U.S. Geological Survey have observed nine polar bears with skin lesions and fur loss over the past two weeks. While the bears otherwise appear healthy, the research team collected blood and tissue samples to determine if there is a relationship between the skin problems seen on the bears and those observed in ringed seals and walruses in the same area earlier this year.
The scientists discovered the symptoms as part of a long-term capture and recapture population study in the southern Beaufort Sea.
Last summer, scientists observed an unusual number of ringed seals hauled out on beaches along the northern coast of Alaska. Later on, they discovered dead and dying seals with skin lesions and hair loss. The observations led to the Unusual Mortality Event by the National Oceanic and Atmospheric Administration on December 20, 2011. Then, during the fall, Pacific walrus in the same area were observed with similar skin sores, leading the U.S. Fish and Wildlife Service to join the investigation.
Since the initial reports from northern Alaska, seals with similar symptoms have also been reported in adjacent regions of Canada and Russia and from the Bering Strait region. Scientists have tested for a wide variety of well-known infectious agents, but don't yet know the cause or whether the symptoms observed in seals, walruses, and now, polar bears, are related.