SPOKANE, Wash. (AP) — Conservation groups filed a lawsuit Monday challenging the U.S. Fish and Wildlife Service’s decision to withhold Endangered Species Act protection from wolverines in the lower 48 states, where no more than 300 of the animals are thought to remain.

The groups said wolverines face localized extinction as a result of climate change, habitat fragmentation and low genetic diversity.

The lawsuit was filed in federal court in Missoula, Montana, and contended that climate change is diminishing the mountain snowpack that wolverines rely on for their primary habitat. Wolverines in the lower 48 seek out areas with persistent spring snowpack to dig dens to birth and raise their young.

“The wolverine is a famously tough creature that doesn’t back down from anything, but even the wolverine can’t overcome climate change by itself,” said Earthjustice attorney Amanda Galvan in a press release.

Earthjustice is representing a broad coalition of groups, including the Center for Biological Diversity, Conservation Northwest, Defenders of Wildlife, Friends of the Clearwater, Idaho Conservation League, Jackson Hole Conservation Alliance, Klamath-Siskiyou Wildlands Center, Greater Yellowstone Coalition, Sierra Club and Rocky Mountain Wild.

“For years scientists have been sounding the alarm on how wolverines are severely affected by climate change,” said Andrea Zaccardi, attorney at the Center for Biological Diversity. “The future of the wolverine in the lower 48 now stands on a knife edge.''

The Fish and Wildlife Service received a petition to protect the wolverine under the Endangered Species Act in 2000, and has fought the designation for years.

The agency issued a statement Monday saying it stood by its recent decision not to list wolverines for protection.

“New research and analysis show that wolverine populations in the American Northwest remain stable, and individuals are moving across the Canadian border in both directions and returning to former territories,'' the statement said. "The species, therefore, does not meet the definition of threatened or endangered under the Endangered Species Act.''

The agency in the past has also suggested the number of wolverines is expanding, not contracting, They predict that enough snow will persist at high elevations for wolverines to den in mountain snowfields each spring despite warming temperatures.

Wolverines, also known as “mountain devils,” were wiped out across most of the U.S. by the early 1900s following unregulated trapping and poisoning campaigns.

Wildlife officials have previously estimated that 250 to 300 wolverines survive in remote areas of Montana, Wyoming, Idaho and Washington state. The animals in recent years also have been documented in California, Utah, Colorado and Oregon.

The animals need immense expanses of wildland to survive, with home ranges for adult male wolverines covering as much as 610 square miles (1,580 square kilometers), according to a study in central Idaho.