BILLINGS, Mont. (AP) - The tenacious wolverine, a snow-loving carnivore sometimes called the "mountain devil," could soon join the list of species threatened by climate change - a dubious distinction putting it in the ranks of the polar bear and several other animals that could see their habitats shrink drastically due to warming temperatures.
Federal wildlife officials on Friday will propose Endangered Species Act protections for the wolverine in the Lower 48 states. That's a step twice denied under the Bush administration.
The Associated Press obtained details of the government's long-awaited ruling in advance of Friday's announcement.
It's likely to mean an end to trapping the animals for their fur.
But federal officials said they won't use the animal's status as a means to regulate the greenhouse gases blamed in climate change. And other human activities - from snowmobiling and skiing to infrastructure development and transportation corridors - would not be curtailed because they do not appear to be significant threats to wolverines, officials said.
There are an estimated 250 to 300 wolverines in the contiguous U.S., clustered in small, isolated groups primarily in the Northern Rockies of Montana, Idaho, Wyoming and Washington. Larger populations persist in Alaska and Canada.
Maxing out at 40 pounds and tough enough to stand up to grizzly bears, the animals will be no match for anticipated declines in deep mountain snows female wolverines need to establish dens and raise their young, scientists said.
In some areas, such as central Idaho, suitable habitat could disappear entirely, officials said.
Yet because those losses could take decades to unfold, federal wildlife officials said there's still time to bolster the population, including by reintroducing them to the high mountains of Colorado.
"This is a species there is still time to do something about," said Mike Thabault, ecological services director for the U.S. Fish and Wildlife Service's mountain-prairie region.
Wildlife advocates, who sued to force the government to act on the issue, said the animal's plight should be used by the Obama administration to leverage tighter restrictions on greenhouse gas emissions.
As with the polar bear, the government is seeking to sidestep that thorny proposition by not addressing threats outside the wolverine's immediate range.
Thabault said the agency would be on tenuous scientific grounds if it tried to draw a link between specific emission sources and impacts on wolverines.
Advocates expressed disappointment, with Noah Greenwald from the Center for Biological Diversity saying the administration "should not be exempting greenhouse gas emissions from the Endangered Species Act."
John Martin, a Washington, D.C., attorney for the energy industry during litigation over polar bears, said he doesn't expect any change in the administration's policy against using endangered wildlife to regulate emissions.
Friday's proposal would allow Colorado's wildlife agency to reintroduce an experimental population of wolverines that eventually could spill into neighboring portions of New Mexico and Wyoming.
But the proposal would shut down wolverine trapping in Montana, the only one of the Lower 48 states where the practice is still allowed.
In recent weeks state officials said they wanted Montana exempted from future trapping restrictions. Montana Fish Wildlife and Parks spokesman Ron Aasheim said Friday the state will review the federal proposal and had not settled on a response.
Once found throughout the Rocky Mountains and in California's Sierra Nevada mountain range, wolverines were wiped out across most of the U.S. by the 1930s due to unregulated trapping and poisoning campaigns, said Bob Inman, a wolverine researcher with the Wildlife Conservation Society.
In the decades since, they have largely recovered in the Northern Rockies but not in other parts of their historical range.
While reintroducing the animals further south might seem counterintuitive, Inman said Colorado's abundance of 14,000-foot mountains make it ideally suited as a refuge for the animals as warmer temperatures set in at lower elevations.
Only one wolverine currently inhabits the state, a male that wandered down several years ago from northern Wyoming. Inman said the state has enough high-mountain territory to support up to 100 more.
"That's like a 30 percent increase in their population size," he added.
Any reintroduction into Colorado would require approval from state wildlife commissioners and the Legislature, Colorado Parks and Wildlife spokesman Randy Hampton said.
Representatives of the state's ski and agriculture industries have previously raised concerns about the potential impacts of wolverines being brought back. Hampton said no decision has been made and it could take years to work out all the details.
Other areas where wolverines once roamed also could serve as future refuges.
Those include portions of Utah, Oregon's Cascade Range, Wyoming's Big Horn Mountains and the Sierra Nevada, said Shawn Sartorius, a biologist with the Fish and Wildlife Service based in Montana.