MISSOULA, Mont. (CN) - Just 35 breeding wolverines remain in the United States yet the U.S. Fish and Wildlife refuses to list the species as threatened, environmentalists claim in court.
The Defenders of Wildlife sued the Secretary of the Interior and the U.S. Fish and Wildlife on Monday in Federal Court.
The ferocious animal with an ornery disposition is the largest terrestrial member of the family Mustelidae, which includes otters, weasels, badgers, ferrets and minks. Known by many names, including the "skunk bear," the powerful animal weighs from 17 to 40 lbs. and resembles a small bear with a bushy tail.
The wolverine has historically been found in the Northern United States, where snowpack is vital for reproductive and rearing purposes.
But the Defenders of Wildlife say wolverine populations are dwindling as habitat shrinks through climate change, and because of extremely low reproductive rates and lack of genetic diversity.
"The metapopulation of wolverines in the contiguous United States ... consists of a network of small subpopulations on mountaintops, some consisting of fewer than 10 individuals," the Defenders said in its 28-page lawsuit.
"The total wolverine metapopulation is estimated to contain 250-300 individuals. The effective population - that part of the population that reproduces - is estimated to be just 35 breeding individuals."
The Defenders sued the Department of the Interior and the U.S. Fish and Wildlife Service in 2000, hoping to compel the agencies to list the wolverine as a threatened species under the Environmental Species Act.
It took 13 years, but Fish and Wildlife finally issued a proposed rule in February 2013, declaring the wolverine threatened based "principally on the expected decrease and fragmentation of the species' habitat and range due to climate change."
But the agency had a change of heart in August this year and withdrew its decision to list the wolverine.
"In its 2014 withdrawal decision, the Service stated that it no longer believes that existing scientific information supported a determination that the wolverine is a threatened species," according to the complaint. "In particular, the Service stated that it no longer believes that the best scientific data available supports its earlier conclusion that wolverine habitat and range are threatened by climate change."
The Defenders claim the decision was based on the same evidence the agency used to determine that the wolverine's habitat was indeed in danger.
"The Service went on to determine, without citing any new or better scientific information addressing the foreseeable impacts of climate change on wolverine habitat and survival that, 'based upon our re-evaluation of the best scientific data available, we no longer find that the existing scientific information supports our conclusions in the proposed rule,'" the complaint states.
The Defenders claims Uncle Sam violated the Endangered Species Act and the Administrative Procedures Act.
They want the court to vacate the Service's decision to withdraw the proposed rule, and to remand the matter for further consideration "in accordance with all requirements of the ESA within six months" of the court's judgment.
The Defenders are represented by house counsel Michael Senatore, in Washington, D.C., and by Summer Nelson with Gentry & Nelson Merrill Law Group, in Missoula, Mont.
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