Polar Bear Population Seen Declining

[EV_Ares]

By JOHN HEILPRIN, Associated Press Writer



A mother polar bear and her cub sleep near the ice outside Churchill, Canada Nov. 4, 2006. Computer predictions of a dramatic decline of sea ice in regions of the Arctic are confirmed by actual observations, according to scientists for the National Oceanic and Atmospheric Administration and could have profound effects on marine mammals dependent on the sea ice such as polar bears, now under consideration by the U.S. Fish and Wildlife Service for "threatened" status under the Endangered Species Act. (AP Photo/CP/Jonathon Hayward, File)


WASHINGTON - Two-thirds of the world's polar bears will be killed off by 2050 _ including the entire population in Alaska _ because of thinning sea ice from global warming in the Arctic, government scientists forecast Friday.

Only in northern Canada and northwestern Greenland are polar bears expected to survive through the end of the century, said the U.S. Geological Survey, which is the scientific arm of the Interior Department.

USGS projects that polar bears during the next half-century will lose 42 percent of the Arctic range they need to live in during summer in the Polar Basin when they hunt and breed.

Polar bears depend on sea ice as a platform for hunting seals, which is their primary food. They rarely catch seals on land or in open water. But the sea ice is decreasing due to climate change _ and the latest forecasts of how much they are shrinking are, if anything, an underestimate, scientists said.

"There is a definite link between changes in the sea ice and the welfare of polar bears," said USGS scientist Steven Amstrup, the lead author of the new studies. "As the sea ice goes, so goes the polar bear."

Scientists do not hold out much hope that the buildup of carbon dioxide and other industrial gases blamed for heating the atmosphere like a greenhouse can be turned around in time to help the polar bears anytime soon.

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