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.
The Interior Department cites thinning sea ice as the big problem; outside the government, other scientists studying the issue say pollution, overhunting, development and even tourism also may be factors.
Greenland and Norway's Svalbard islands have the most polar bears, while a quarter of them live mainly in Alaska and travel to Canada and Russia.
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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 steadfast 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.
That vote put into effect a 2000 treaty that sets quotas on polar bear hunting by native populations in the two countries and establishes a bilateral commission to analyze how best to sustain sea ice. It also approved spending $2 million a year through 2010 for the polar bear program.
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, put at risk by melting sea ice, pollution, hunting, development and even tourism.
The group lists the polar bear among more than 16,000 species threatened for survival worldwide, and projects a 30 percent decline in their numbers over the next 45 years. It says sea ice is expected to decrease 50 percent to 100 percent over the next 50 years to 100 years.
The decision from Interior's Fish and Wildlife Service, which oversees endangered species, coincides with a court-ordered deadline.
After Fish and Wildlife officials missed a deadline for deciding earlier this year, the groups sued and agreed on Wednesday's deadline.
"This is a victory for the polar bear, and all wildlife threatened by global warming," said Kassie Siegel, a lawyer for the Center for Biological Diversity. "There is still time to save polar bears, but we must reduce greenhouse gas pollution immediately."