Wolverine Proposed For Listing As A Threatened Species, Could Affect Yellowstone Winter Use
Yellowstone National Park officials are monitoring the proposed listing of the wolverine as a threatened species, and will determine whether they need to reconsider snow travel over Sylvan Pass if the listing becomes formal.
"We recognize that this is a species that people have had an interest in in our ecosystem, and at the very least, should the wolverine be added to the endangered list, we’d have to look at what we might need to do with any of our environmental compliance in response," said park spokesman Al Nash. "But at this point we just don’t know more than that.”
The U.S. Fish and Wildlife Service announced Friday the listing proposal under the Endangered Species Act. A 90-day public comment period on the proposal opens today.
If the listing is approved, the most immediate affect would be a halt to Montana's wolverine trapping season, which allows an annual take of five animals. The proposed listing also includes language that would permit a "nonessential experimental population" of wolverines to be established in southern Colorado, southern Wyoming, and northern New Mexico through a recovery program.
“By allowing them to reclaim those places, that can help the overall population last longer," Kylie Paul, the Rockies and Plains representative for Defenders of Wildlife, said Friday in reference to the high, snowy elevations being eyed as wolverine recovery zones.
Climate change is the major obstacle to wolverine recovery. These opportunistic carnivores -- they are known to scour avalanche chutes for animals killed in slides -- once roamed wide and far across the continental United States. Historical populations were found in the coastal mountains of California, Oregon, and Washington, and they roamed the Rocky Mountains from Glacier National Park on the Canadian border all the way south to Taos, New Mexico, east into the Great Lakes region, and even in the Northeast.
But female wolverines build their dens in snowﬁelds, and warmer winters are shrinking those snowfields.
“Their primary threat is climate change, and habitat loss due to climate change. By the end of this century, they could lose two-thirds of their habitat in the lower 48," said Ms. Paul.
At Earthjustice, the law firm that represented conservation organizations in suing the Fish and Wildlife Service to consider listing the wolverine, Timothy Preso said the wolverine, like the polar bear, is the proverbial canary in the coal mine whose fate will be determined by climate change.
“Our biological heritage is at risk as we start cooking the planet, as we as a society are doing right now," he said. “If we continue on the path we are on right now, burning all the fossil fuels we can get our hands on, it’s going to be too late for a lot of things, the wolverine being the least of them.”
Fortunately, much of the remaining habitat that might be appealing to wolverines is found in high, alpine settings already within the federal lands kingdom and which see few humans.
In Friday's announcement regarding the proposed listing, Fish and Wildlife officials estimated the current wolverine population in the Lower 48 states at between 250 and 300 individuals.
While areas considered to be critical habitat for threatened or endangered species often is delineated by the wildlife agency, in its proposed listing announcement it said more time was needed "to assess the potential impact of a critical habitat designation and to identify specific areas that may be appropriate for critical habitat designation."
"The Service seeks comments on the reasons we should or should not designate critical habitat for the wolverine, and what specific areas might be considered for designation," the announcement added.
Parts of the greater Yellowstone ecosystem, which encompasses Yellowstone and Grand Teton national parks and the surrounding national forests, have been recognized as suitable for wolverines.
A four-year search, from 2005 into 2009, for wolverines in Yellowstone and the ecosystem neighboring the eastern half of the park detected surprisingly few of the carnivores. And yet, the researchers concluded that the park has increasingly valuable habitat that could help the species avoid extinction in the contiguous United States.
The goal of the study was to better define presence of the small, but feisty, carnivore in the park and greater Yellowstone ecosystem. But the results were disappointingly small. Just four wolverines were captured during the study period, although biologists were also able to monitor three others that previously had been captured and fitted with transmitters by Wildlife Conservation Society biologists.
Along with the seven individuals that turned up in the greater Yellowstone search, in recent years wolverines have been tracked in Grand Teton National Park, found on the landscape containing North Cascades National Park, and photographed in Rocky Mountain National Park. Glacier National Park boasts the highest densities of wolverines in the 48 contiguous states, with between 40 and 50 individuals estimated.
Though Yellowstone doesn't feature as much optimal wolverine habitat as does Glacier, the park is twice as large, and does contain habitat that should support at least 8-10 individuals, according to wildlife biologists.
What is known about the wolverine in Yellowstone these days is that there are precious few. And that they on occasion pass through the Sylvan Pass area, as evidenced in 2009 when wolverine tracks were spotted on the pass, according to one of Yellowstone's winter-use environmental impact studies.
In that EIS, park officials acknowledged that bombing the avalanche chutes above Sylvan Pass to permit safe passage of recreational snowmobiles and snowcoaches isn't the best thing for wolverines. They noted that "(Over-snow vehicle) use and maintenance (particularly avalanche control methods) may cause wolverines using the area to leave, and/or cause females to abandon their dens for poorer den sites, increasing kit mortality and decreasing the reproductive success of wolverines."
In the end, though, those who prepared the report concluded that avalanche control and snowmobile use over Sylvan Pass would result in "minimal disturbance to wolverines."
If the current proposal to list the wolverine as a threatened species, Yellowstone officials might have to revisit their thinking on keeping Sylvan Pass open in winter.
“We’d have to look at our existing, and ongoing, and proposed compliance to see what we would need to do to be approrpirately responsive to that," said Mr. Nash on Friday.
From Mr. Preso's viewpoint, "Detonating explosives in the middle of wolverine habitat is probably not something that will make wolverines stick around.”
The Fish and Wildlife Service has scheduled three informational sessions and public hearings on this proposed rule:
* Boise, Idaho: March 13, 2013 at the Boise Centre on the Grove, 850 West Front Street, Boise, ID 83702.
* Lakewood, Colorado: March 19, 2013 at the Hampton Inn, 137 Union Boulevard, Lakewood, CO 80228.
* Helena, Montana: March 27, 2013 at the Red Lion Colonial Inn, 2301 Colonial Drive, Helena, MT 59601.
At all three locations the public informational session will run from 2 p.m. to 5 p.m., followed by public speaker registration at 6 p.m., and then the public hearing for oral testimony from 7 p.m. to 9 p.m.