Wildlife advocates want a United States judge to force the government into deciding if the snow-loving wolverine should be federally protected as it becomes vulnerable to a warming planet.

The request came in a lawsuit filed Wednesday, almost four years after the judge ordered wildlife officials to take swift action to protect the rare animal.

Also known as “mountain devils,” wolverines are fierce but elusive predators once found throughout the Rocky Mountains. They were wiped out across most of the U.S. by the 1930s following unregulated trapping and poisoning campaigns.

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An estimated 250 to 300 wolverines survive in the Lower 48 states, with populations also in Alaska and Canada.

In Washington state, a population of 13 wolverines has been studied in the North Cascades from 2005 to 2013. Wolverines have recently been seen near Mount Adams and in the Goat Rocks Wilderness in the South Cascades, according to the Washington Department of Fish and Wildlife.

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