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 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 species 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 that the Fish and Wildlife Service did a careful and comprehensive analysis before deciding that 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 for the bears to find food.
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.