The polar bear should be removed from the endangered species list because its protected status will hamper drilling for oil and gas in Alaska, the state's Republican Governor has demanded.

Sarah Palin is suing the Bush Administration over its decision last week to place the animal under the protection of the Endangered Species Act, claiming that climate models predicting the continued loss of sea ice - the main habitat of polar bears - are unreliable.

The lawsuit came as a surprise because most of the outcry after last week's decision came from environmental groups. Although pleased that the Bush Administration had singled out climate change as a reason to place an animal under the protection of the Endangered Species Act, the green lobby were dismayed about restrictions attached to the listing.

The listing came with a big caveat: that it should not be misused to harm the economy and “set backdoor climate policy”. Some environmentalists also accused the Administration of deliberately delaying the ruling to make it easier for oil companies to finalise $2.7 billion (£ 1.35 billion) in offshore oil leases in the Chukchi Sea, an area that is home to about 20 per cent of the world's polar bears. Numerous lawsuits were threatened by the green lobby.

Yet the Governor of Alaska - a state whose residents overwhelmingly support oil exploration - is arguing that the polar bear does not need added protection, and the bear populations have increased significantly over the past 30 years because of conservation. Ms Palin maintains that any commercial development in Alaska requiring federal permits or funding would have to go through a consultation process - described by Steven Daugherty, Alaska's assistant Attorney-General, as “basically a big time-and-money waster”.

He added: “We believe that the listing was unwarranted and that it is unprecedented to list a currently healthy population based on uncertain climate models.”

There are an estimated 20,000-25,000 polar bears in the Arctic, but scientists from the US Geological Survey predict that two thirds of the world's bears will disappear in the next 50 years because of a decline in the Arctic sea ice.

In a stark warning last year, scientists at the National Snow and Ice Data Centre said that the total Arctic ice cover had melted to its lowest level in modern times, and that if melting rates continued the summertime Arctic could be ice-free within 80 years.

Kassie Siegel, of the Centre for Biological Diversity, said that it was unconscionable for Ms Palin to ignore overwhelming evidence of global warming's threat to the polar bear's habitat. “Even the Bush Administration cannot deny the reality of global warming,” she said. “The Governor is aligning herself and the state of Alaska with the most discredited, fringe, extreme viewpoints by denying this. “She is either grossly misinformed or intentionally misleading, and both are unbecoming. ”

Dirk Kempthorne, the US Interior Secretary, who made the listing, said that it was based on three findings. “First, sea ice is vital to polar bear survival; second, the polar bear's habitat has dramatically melted; third, sea ice is likely to further recede in the future.”

Changing list

48 species have been removed from the endangered list since 1976

17 of these were taken off after errors in the original data

9 species have been been delisted because of extinction

Rocky mountain grey wolves were removed from the list this year after controversial reintroduction programmes increased their numbers to more than 1,500

Idaho springsnail was removed from the list last year after the Fish and Wildlife service responded to a petition from the Idaho Governor’s Office arguing that its listing in 1992 was in error

Yellowstone grizzly bear was removed from the list last year. In 1975 their numbers in the Yellowstone ecosystem dwindled and the species was in danger of total disappearance. But by 2007 there were more than 500 — no longer meeting the Endangered Species Act’s definition of threatened or endangered

Source: US Fish and Wildlife Service

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