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THE American government is to add the polar bear to its list of endangered species.

Even though the world’s polar bear population is stable, the US Geological Survey predicts that it will fall by two-thirds by 2050 if the Arctic ice where the animals live continues to shrink.

The US Interior Department said an announcement would come “sooner rather than later”.

The plan was welcomed by environmentalists such as Andrew Wetzler, of the Natural Resources Defense Council, who said it would be a rare White House acknowledgement of damage caused by global warming.

Limits on the hunting of polar bears have led to a rise in their numbers from about 10,000 in the 1970s to 25,000 today. Their biggest problem now is the shrinking icecaps. Conservationists also believe restricting Alaskan development in sensitive areas and capping industrial pollution elsewhere would help.

WWF, the international conservation group, suspects the classification of polar bears as endangered has been delayed because the US administration is selling oil and gas exploration rights off the Alaskan coast. The sale might be impossible if the bears’ habitat were already protected.

Chris Tollefson, a government spokesman, said the timing of the two events was coincidental. “They have moved on parallel tracks, but both driven by the complexity of the science involved,” he said.

Another official, who declined to be named, said: “The decision [on polar bears] has been taken in principle, but the announcement will follow shortly.”

There are “reservations” to be digested, he said, including questions raised by Alaska’s Republican governor, Sarah Palin.

Palin, 42, favours expanding the oil business. She says polar bears could be protected under existing laws without undermining the Alaskan economy.

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