Colorado lawmakers last week overwhelmingly approved a bill to restore North American wolverines to the state’s high country.
Supporters say the wolverine is one of the last species still “missing” from Colorado after it was exterminated from the Rocky Mountains by humans in the early 1900s.
Conservation groups are celebrating the approval of the wolverine restoration bill. They see Colorado as a key piece of a strategy to ensure the survival of the extremely solitary member of the weasel family.
Between 300 and 400 wolverines are currently estimated to live in the lower 48 states. The animal was listed as threatened under the Endangered Species Act in November, sparking this year's effort at the state Capitol to begin restoration.
Wildlife officials say Colorado could eventually host as many as 180 wolverines.
Colorado Parks and Wildlife (CPW) officials are now busy dusting off and updating restoration plans they’ve had for the animal since 2010.
When can I expect to see wolverines in the high country?
No date has been announced quite yet. There’s still a lot of work left to do.
First, state officials say they need to find a place to get the donor wolverines from. They’re also still writing a reintroduction plan.
Finally, the federal government also needs to approve a request to designate the wolverines as an experimental population, which gives the state more flexibility to manage the species. That process could take as long as two years.
What’s Colorado’s history with wolverines?
It’s now been more than a century since wolverines thrived in the mountains of Colorado.
Humans exterminated them from the state in 1919.
“We think that widespread predator poisoning campaigns and unregulated trapping were the main sources of their demise,” CPW Species Conservation Unit Supervisor David Klute said last week during a briefing on potential reintroduction plans.
Surveys from the 1970s through the 1990s did not find any evidence of wolverines in the state.
Why is Colorado so important to the future of wolverines?
It’s all about the habitat. Wolverines thrive at high altitude in the cold and snow on rocky tundra. They den deep under the snow and cache their food in it. And Colorado has the biggest swath of land left in the United States where wolverines could thrive.
In fact, Parks and Wildlife says Colorado holds about 20% of the estimated wolverine habitat in the entire Western United States.
“We could be restoring a population in somewhat of a climate change refugium,” CPW’s David Klute said during a briefing last week. “Colorado's High Country is expected to weather climate change as good or possibly better than Wolverine habitat that is provided by lower elevations and other parts of the range further north.”
Will they attack cows and other livestock?
Scientists say it’s very unlikely.
“We expect the risk of livestock depredation due to wolverines to be very low,” said CPW researcher Jake Ivan.
That's largely because wolverines tend to live in high-altitude areas away from livestock.
The animals are also good scavengers. And in the summer, they turn into effective hunters, killing and eating marmots and other rodents.
Although rare, there have been instances of wolverines killing livestock in the past.
The Grand Junction Daily Sentinel reported on a 2022 incident where a wolverine was believed to have killed and eaten several sheep in northeastern Utah.
Steve Torbit, a retired wolverine researcher, told the Sentinel he suspected the wolverine was “lost and hungry” and looking for better habitat when it found the sheep.
Colorado plans to compensate ranchers for any livestock killed by wolverines.
Some ranching groups opposed the legislation to restore wolverines, citing concerns about them attacking livestock.
Where will wolverines be released?
Three release zones spanning much of the Western Slope have already been identified. The first is in northern Colorado in high altitude areas stretching from Rocky Mountain National Park west to Steamboat Springs. Other release zones include the central mountains and another large area in southwest Colorado between Alamosa and Durango.
What will the release process look like?
CPW says it will likely release up to 45 wolverines over three years. But unlike the wolf reintroduction, the animals won’t be immediately sent off into the wild after they’re captured and brought to Colorado.
Instead, CPW is suggesting that the wolverines have a sort of acclimation retreat to ease into their new surroundings. The animals would be brought to the Frisco Creek Wildlife Rehabilitation Center in Del Norte, where they’ll undergo health exams and get fitted with GPS collars. Scientists will also monitor the animals to find out which ones are paired up so they can release them in the same area together.
I still have more questions. Where can I learn more?
See the full presentation about the upcoming wolverine restoration from CPW here.
