WASHINGTON -- Polar bears are in jeopardy and need stronger government protection because of melting Arctic sea ice related to global warming, the Bush administration said Wednesday.

Pollution and overhunting also threaten their existence. Greenland and Norway have the most polar bears, and a quarter of them live mainly in Alaska and travel to Canada and Russia.

		AP
	This undated file photo released by the U.S. Fish and Wildlife Service shows a sow polar bear resting with her cubs on the pack ice in the Beaufort Sea in northern Alaska. Polar bears are in deep trouble because of global warming and other factors and deserve federal protection under the Endangered Species Act, the Bush administration is proposing Wednesday.

Interior Secretary Dirk Kempthorne on Wednesday proposed listing polar bears as a "threatened" species on the government list of imperiled species. The "endangered" category is reserved for species more likely to become extinct.

"Polar bears are one of nature's ultimate survivors, able to live and thrive in one of the world's harshest environments," Kempthorne said.

"But we are concerned the polar bear's habitat may literally be melting."

A final decision on whether to add the polar bears to the list is a year away, after the government finishes more studies.

Such a decision would require all federal agencies to ensure that anything they authorize that might affect polar bears will not jeopardize their survival or the sea ice where they live. That could include oil and gas exploration, commercial shipping or even releases of toxic contaminants or climate-affecting pollution.

Kempthorne, however, said his department's studies indicate that coastal and offshore oil and gas exploration -- heavily promoted by the Bush administration, particularly in Alaska -- shouldn't be curtailed.

"It's very clear that the oil and gas activity in that area does not pose a threat to the polar bears," he said.

Similarly, Alaskan natives and other people who depend on hunting the bears as part of their subsistence diet probably will not be affected, Kempthorne said.

Sen. Barbara Boxer, D-Calif., the incoming head of the Senate Environment and Public Works Committee, said the polar bear's plight reflects the health of the planet.

"Global warming is melting polar ice at an alarming rate, and we are now beginning to realize the consequences of this," she said. "This news serves as a wake-up call to the U.S. Congress and the administration that we must quickly begin to address global warming through legislative action."

Environmentalists hope that invoking the Endangered Species Act protections eventually might provide impetus for the government to cut back on its emissions of carbon dioxide and other heat-trapping "greenhouse" gases blamed for warming the atmosphere.

The proposed listing also marks a potentially significant departure for the administration from its cautious rhetoric about the effects of global warming.

Kempthorne cited the thinning sea ice brought about by global warming as the main culprit, although he said his department wasn't required by the endangered species law to study climate change.

President Bush's refusal to go along with United Nations-brokered mandatory controls on carbon dioxide, the chief global warming gas, has contributed to tensions between the United States and other nations.

Polar bears, an iconic and cold weather-dependent animal, are dropping in numbers and weight in the Arctic. In July, the House approved a U.S.-Russia treaty to help protect polar bears from overhunting and other threats to their survival.

The Polar Bear Specialist Group of the World Conservation Union, based in Gland, Switzerland, has estimated the polar bear population in the Arctic is about 20,000 to 25,000.