The future of wolverines

By Kylie Paul, Defenders of Wildlife

After more than a decade of legal hand-wringing, the U.S. Fish and Wildlife Service (FWS) finally proposed on Feb. 1 to protect wolverines in the lower 48 states as a threatened species. But invoking the Endangered Species Act alone is not going to save wolverines from looming threats on a warming planet.

Scientists believe there are as few as 250 to 300 wolverines across the entire lower 48. Those numbers sound alarmingly low, though wolverines naturally exist in low numbers because they have large home ranges and reproduce slowly. But this small population is facing an even greater challenge: climate change. Wolverines need deep springtime snow for denning – and scientists predict that wolverines will lose 63 percent of their suitable snowy habitat in the lower 48 by 2099. Further, if that remaining habitat becomes too fragmented, then reduced genetic diversity is likely, and the resulting tiny isolated populations will be at risk of disappearing altogether.

So what do we do? With many endangered species there is a clear path to recovery based on addressing immediate threats. For instance, with bald eagles and other birds of prey, banning harmful pesticides like DDT made recovery a reality. For other plants and animals, protecting habitat can provide enough relief to allow species to recover on their own. Not so with the wolverine. The best bet for securing a future for wolverines is to help them reclaim habitat they once occupied, especially where their historic habitat is most likely to persist into the future.

Enter Colorado. Based on climate and habitat models, much of the Colorado Rockies is expected to retain the kind of deep snowpack wolverines need to successfully rear their young. The problem is there’s only one known wolverine currently living in Colorado. In 2009, researchers with the Wildlife Conservation Society tracked a lone male wolverine known as M56 as he traveled 500 miles from near Grand Teton National Park into north-central Colorado. M56 is thought to be the region’s first wolverine in over 90 years, but he can’t start a new population on his own. And with so few wolverines in the lower 48, it’s unlikely that a female companion is going to find him without a little help. That’s why the FWS proposal includes provisions to pave the way for a wolverine reintroduction program in Colorado, though a decision to move forward on such an effort has not yet been made.

A key part of the listing proposal would designate the southern Rockies as a “nonessential, experimental” population area. This basically means that current land uses and activities can continue unchanged if wolverines are reintroduced to Colorado in the future—a compromise that should help Colorado Parks and Wildlife get the necessary approval for a reintroduction from the Colorado legislature and the state wildlife commission.

A wolverine reintroduction in Colorado is something everyone can support. Wolverines naturally exist at very low densities. They are not a threat to livestock or big game. And the vast majority of wolverine habitat in the lower 48 (94% according to FWS) is already federally owned and managed.  In the proposed listing, federal biologists determined activities like winter recreation, timber management, and development are not a threat to the overall wolverine population, so those activities will not be curtailed across any part of its range, whether in Colorado or elsewhere.   A potential reintroduction in Colorado (and hopefully elsewhere over time) simply will not impact most of us at all -- beyond knowing that wolverines will have more places to call home and a better chance of surviving for generations to come.

Federal protections for wolverines will ensure an end to wolverine trapping in Montana and will provide more attention and resources to wolverine conservation. But getting them listed and protected from direct trapping mortality is still just the first step. Now is the time to work on the long-term effort of helping wolverines reclaim snowy alpine refuges that are likely to persist in a warming world. In the bigger picture, the more complicated effort of combating climate change will be even more important, not just for wolverines, but for all of us.

Essays in the Range blog are not written by High Country News. The authors are solely responsible for the content.

Kylie Paul is Rockies and Plains representative for Defenders of Wildlife in Montana. She thinks wolverines are the coolest critters this side of the Mississippi.

NOTE: Three public hearings will be held in March to provide more information about the federal listing proposal. Visit the U.S. Fish and Wildlife Service’s wolverine page to learn more about how you can participate and submit comments on the proposal.