Wolverines may finally be getting the federal protections they need. After more than a decade of advocacy by Defenders of Wildlife and our conservation partners, the U.S. Fish and Wildlife Service (FWS) announced in February its proposal to list the wolverine as a threatened species in the lower 48 states under the Endangered Species Act (ESA). (You can share your opinion on the listing proposal with the FWS until Monday, May 6, 2013.)
Three-feet long and weighing around 40 pounds, the wolverine is the largest -- and arguably the toughest -- member of the weasel family. This incredible animal treks through the rugged alpine environment near or above timberline all year long and is considered by many to be the living embodiment of wilderness. Wolverines are specially adapted for winter existence. They survive in their snow-covered environment with the help of large paws that act like snowshoes and crampon-like claws that help them to climb up and over steep cliffs and snow-covered peaks.
Wolverines are fearless. They have been known to drive grizzly bears away from carcasses and have been documented climbing 5,000 vertical feet in the middle of winter in less than two hours! Despite their tough reputation, wolverines also have a surprisingly social side. They have strong family bonds, and males will spend time interacting with their young after they leave their mother.
Unfortunately, the wolverine isn't invincible. Scientists estimate that there are 250 to 300 wolverines in the entire lower 48 states. But it's not just a small population that is threatening the wolverine. They face an even greater challenge: climate change. Wolverines need deep snow to remain on the ground through mid-spring for denning and to provide warmth and shelter for their young. Unfortunately, scientists predict that wolverines will lose 63 percent of their suitable snowy habitat in the lower 48 by 2099.
To give this remarkable species a chance to adapt to the warming climate, wolverines need a well-connected, robust population and the opportunity to move into quality former habitat that is most likely to retain spring snow into the future.
And that is where Colorado comes into play.
In 2009, a lone male wolverine, known as M56, traveled 500 miles from near Grand Teton National Park in Wyoming into north-central Colorado. Before M56 was spotted in Rocky Mountain National Park, the last confirmed wolverine sighting in Colorado was in 1919. Colorado has quality wolverine habitat and enough food to support a population, but M56 can't start a family on his own, and it's unlikely that a female companion is going to find him without a little help.
Additionally, some climate models show that Colorado -- with the highest average elevation of any state in the lower 48, including 54 peaks over 14,000 feet -- will likely retain the continuous cold temperatures and snow cover necessary for the wolverine to reproduce and survive. That is why, in addition to the proposed listing, the FWS also announced its proposal to designate the southern Rocky Mountains (southern Wyoming, Colorado and northern New Mexico) as an experimental population area for wolverines, which opens up the possibility of a wolverine reintroduction into Colorado.
Though a decision by Colorado Parks and Wildlife (CPW) to move forward with an reintroduction effort has not yet been made, an experimental population designation should help CPW get the necessary approval for a reintroduction from the state wildlife commission and the Colorado state legislature.
The FWS listing proposal is cause for hope for these imperiled carnivores as federal protections will provide more attention and resources to wolverine conservation. However, listing the wolverine as a threatened species is simply the first step. Now is the time to work on the long-term effort of helping wolverines reclaim snowy alpine refuges that are unlikely to persist in a warming world.