The elusive wolverine, long since extinct from the Southern Rockies, could be returning under a plan being floated by state wildlife officials. Meanwhile, the mammal is also being considered for protection under the Endangered Species Act in its existing habitats in Wyoming and Montana. The designation likely would have little effect io the Colorado reintroduction, which would be classified as an “experimental, nonessential” population./Photo courtesy Colorado Parks and Wildlife

Bringing back the wolverine

State wildlife officials explore possibilities of reintroduction
by Allen Best

If the climate continues to warm, as global warming theory says will most certainly happen, what better place for the wolverine, a snow-loving ball of ferocious fur, to make a stand than in Colorado’s high mountains and adjoining areas of Wyoming and New Mexico?

“Colorado will certainly lose snowpack, but at a slower rate” than other, lower-elevation regions of the West where wolverine are currently found, said Eric Odell, species conservation coordinator for Colorado Parks and Wildlife. He called Colorado a “climate-safe refuge” for the snow-loving mammal.

Odell, working with representatives of the U.S. Fish and Wildlife Service, has been mapping a plan to transplant several dozen wolverines from Canada and Alaska into Colorado in the hope of achieving a sustainable population of more than 100.

This, state and federal wildlife biologists say, would make the population of wolverines in the lower 48 more resilient in the faces of warming temperatures.

The reintroduction in Colorado must still be approved by both the state’s Wildlife Commission, a board appointed by the governor, and the state Legislature.

“It’s a big ‘if’ whether we will do this,” Odell said in a presentation at the Denver Zoo sponsored by Rocky Mountain Wild, a Durango-based advocacy group. “We have to have political, social and economic concerns addressed before we do this.”

U.S. wildlife officials estimate that only 250 to 300 wolverines exist in the lower 48, with the largest concentration in Glacier National Park and adjoining areas of Montana. Wolverines also roam parts of Wyoming, Idaho, Oregon and Washington state. Western Canada has an estimated 13,000 adults, and Alaska has at least several thousand more, according to a Feb. 4 filing in the Federal Register. This compares with the 1,000 wolverines killed annually by trapping.

If the reintroduction goes forward, Colorado would translocate 10 to 20 individuals annually for at least four years, at a ratio of five females for every two males. They would be released at various locations, as wolverine require vast amounts of territory.

Colorado originally had wolverines, but the last confirmed animal died in 1919. Like Canada lynx, which remained at least until the 1970s, wolverines were killed by trappers but were also collateral damage in a broad campaign to kill all predators through traps and poison.

Then, in spring 2009, a young male wolverine that had been fitted with a radio collar in Grand Teton National Park was observed by radio telemetry wandering south toward Colorado. Two months later, he reached Rocky Mountain National Park, and he has remained in Colorado since.

Wildlife biologists say another male might also come to Colorado, but not females, who would be more cautious about crossing Wyoming’s high deserts.

Sometimes mistaken for small bears, wolverines weigh 25 to 35 pounds and are about 3 to 3 ½ feet long, with stocky bodies, rounded ears and broad heads. Their fur is brown with a yellowish-brown swath down their sides and across their foreheads.

Opportunistic carnivores, they eat everything from small rodents to deer, if the latter is weakened by illness or bogged down in deep snow. Mostly, however, they eat carrion. Because of large paws, which are as big as those of a wolf, they thrive in deep snow. They also have a sharp sense of smell, able to pick up the scent of an animal killed by an avalanche 20 feet below the snow. As a PBS movie noted, avalanche country is wolverine country.

But the places they call home have a thin menu. Because they have such a hard time scaring up dinner, they have to wander far and wide, which they do well. The home range for one wolverine can be close to 40 square miles – not exactly a studio apartment.

Stories abound of the amazing physical abilities of wolverines. In Glacier National Park, a wolverine ran to the summit of the park’s highest mountain in 90 minutes, a climb of 4,000 feet. The reason? Perhaps, like Edmund Hillary, “because it’s there.”

Wolverines need snow and cold. Females den in places where snow lingers into mid-May, serving as a thermal barrier and a deterrent to predators.

And Colorado, despite global warming, offers that. Biologists estimate that Colorado has 11,500 square miles of high-elevation terrain suitable for wolverines, most on Forest Service land.

In early February, federal wildlife officials proposed protection for the wolverine under the Endangered Species Act, which was twice denied under the Bush administration and then postponed by the Obama administration. If the listing occurs, trapping for fur in Montana, which is now allowed, would cease. However, Colorado and federal wildlife officials say they see little or no impact to timber harvesting, ski areas and other uses is the animal is listed.

Colorado has been approaching the reintroduction much more cautiously than that of the Canada lynx, which began in 1999 and has now been deemed a success. But there were snarls and scratches at the outset. Ranchers were apprehensive, and so were recreation businesses and users, worried that the presence of the species would curtail activities.

Then, when the first lynx were released, they promptly died of starvation, affirming the biases of those who had argued there had been a reason lynx disappeared from Colorado. Before the next lynx from the northern boreal forests were released, they were fattened up, to better prepare them for their new surroundings. Once established, however, they have been finding plenty of rabbits and other prey. There has been mortality, with roadkill being significant, but very little starvation.

To prevent similar miscues this time, Colorado officials have outlined plans to provide denning wolverines with carrion upon their release, to ensure they don’t go hungry while becoming familiar with their surroundings.

State wildlife officials have also convened meetings of stakeholder groups, including the ski industry, off-road vehicle groups and environmental advocates.

Odell said wolverine would be unlikely to kill cattle, but sheep might be targeted occasionally. However, because wolverine range so broadly, no one part of Colorado would have large numbers, and any impacts would be minimized, say officials.

If the reintroduction program does go forward, wolverines in Colorado would be classified as an experimental, nonessential population, meaning the wolverines would have fewer protections than is normally the case under the Endangered Species Act.

Colorado, in a sense, is making the counter argument that the reintroduction is needed to help wolverines remain in the lower 48 states.

Catilin Balch-Burnett, a representative of Defenders of Wildlife, say the reduced protections would be a compromise, but the reintroduction would be “our best chance for getting wolverines on the ground” in Colorado.

Allen Best can be found at http://mountaintownnews.net