Wolverine Loses Ground


     WASHINGTON (CN) - Despite its public image as a fierce fighter, the wolverine is no match for the relentless march of climate change that is steadily melting away the spring snowpack the animals use for denning. The U.S. Fish and Wildlife Service has released twin proposals to protect the diminishing North American wolverine population, according to the agency's press release.
     A proposal to establish a nonessential experimental population (NEP) in Colorado to reintroduce the species into part of its historical range is dependant on the finalization of a separate proposed rule to designate the wolverine as a threatened species under the Endangered Species Act, the agency said.
     In the early 1900s, the ferocious weasel-family member was trapped and poisoned to the brink of extinction in North America. Since that time, the population has recovered somewhat due to state protections. The current estimated population for the lower 48 states is 250 to 300 animals. Now the species is most threatened by climate warming.
     "Wolverines require habitats with near-arctic conditions wherever they occur. In the contiguous United States, wolverine habitat is restricted to high-elevation areas in the West. Wolverines are dependent on deep persistent snow cover for successful denning, and they concentrate their year-round activities in areas that maintain deep snow into spring and cool temperatures throughout summer," the proposed rule noted.
     The distinct population segment of wolverines in the contiguous United States is considered a metapopulation which is "composed of a network of semi-isolated subpopulations, each occupying a suitable patch of habitat in a landscape of otherwise unsuitable habitat." In addition to providing appropriate denning sites, the dense snowpack facilitates movement of individuals between subpopulations to prevent inbreeding. Subpopulations can contain as few as ten individuals, according to the action.
     The listing proposal is in response to a settlement with the Center for Biological Diversity (CBD) requiring the federal agency to speed listing decisions for 757 species. Once the proposed listing is finalized, the proposed NEP in Colorado can be established.
     "Endangered Species Act protection for wolverines will likely put an end to plans by the state of Montana to allow wolverine trapping. It also will mean a likely reintroduction of the animals to Colorado, with [the] rule allowing for wolverines to be moved to the state under relaxed regulations that defines released animals as experimental and nonessential. Similar rules have been used to reintroduce wolves to Yellowstone National Park and the Southwest and black-footed ferrets to several areas," the CBD noted in its statement.
     Once a species has listing protection under the Endangered Species Act, a special section of the act allows for the establishment of experimental populations to reintroduce animals into parts of its historic range. These experimental populations contribute to the conservation of the species, but are considered to be nonessential if the loss the experimental population would not endanger the overall survival of the species, as in this case, the agency said.
     Comments on the listing proposal are due May 6. Three public information sessions and hearings will be held in Colorado, Idaho and Montana.
     Comments on the proposed NEP are also due May 6, and one public hearing will be held in Colorado.