A federal appeals court has rejected the state of Alaska's attempt to remove polar bears from the threatened species list.
Friday's decision by the U.S. Court of Appeals for the District of Columbia has major implications, because polar bears were the first species to be listed solely on the basis of threats to their survival from global warming.
The D.C. appeals court affirmed a lower court ruling supporting the U.S. Fish and Wildlife Service's decision to put polar bears on the federal threatened list.
Polar bears are not today on the brink of extinction. But the Fish and Wildlife Service says melting sea ice means two-thirds of the world's polar bears could be gone by 2050.
The appeals court ruled Friday that the Fish and Wildlife Service did a careful and comprehensive analysis before deciding the bears deserve protection.
"Its scientific conclusions are amply supported by data and well within the mainstream on climate science and polar bear biology," said the ruling, which was written for the court by Judge Harry Edwards.
The court said there's no dispute that sea ice is melting. The ice reached a record low this summer, according to the National Snow and Ice Data Center. Polar bears spend much of their lives hunting seals from sea ice.
The Fish and Wildlife Service said the anticipated further loss of sea ice habitat will make it harder to find food and force the bears to swim tremendous distances between ice, putting them at risk for drowning.
The D.C. appeals court said the agency considered what's already happening in areas where the sea ice loss has been most severe, such as a population decline in the Western Hudson Bay population of polar bears.
The state of Alaska had joined with hunting groups and others in fighting the threatened listing. The appeals court said Friday that several of the challenges "rely on portions of the record taken out of context and blatantly ignore FWS's published explanations."
Other challenges amount to just competing views about policy and science, the appeals court said, adding that it defers to the Fish and Wildlife Service on those.
The Alaska governor's office did not have an immediate response to its court loss. The Center for Biological Diversity, which petitioned for the polar bears to be listed, called the ruling the latest legal confirmation of the threat that climate change poses to them.
"What we need now is for the Obama administration to cut greenhouse pollution and save the bears," said Kassie Siegel, senior counsel for the group.
Murray Feldman, a private attorney who represented Alaska and the other appellants, said during October oral arguments that the bears are doing fine overall. "Polar bears occupy the entirety of their historic range, with population at an all-time high," Feldman said.
Among Feldman's arguments was that the Fish and Wildlife Service used flawed population models. But the court found those models were simply used to confirm other findings and were not a central part of the decision to list the bears. He also argued that the Fish and Wildlife Service inadequately explained how the predicted decrease in habitat would likely lead to such a dramatic population decline in the coming decades.
The court disagreed. "The agency carefully and clearly explained how this particular habitat loss leaves this particular species likely to become endangered," Judge Edwards wrote in Friday's ruling.
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