Four western states along with federal, tribal and university partners are combining efforts in an unprecedented inventory of one of the high country’s most elusive carnivores.
Wolverines, the largest members of the weasel family, live at low densities across some of the most remote and rugged terrain in the lower 48, Canada and Alaska. Weighing up to 40 pounds with large feet adapted for snow travel, the rare animals have long earned a reputation for their tenacity and ability to thrive where few other animals survive.
Researchers have traditionally studied wolverines anecdotally or with small-scale projects in known hotbeds in a few mountain ranges and national parks. Montana, Idaho, Wyoming, Washington and their partners are about to change that.
“It’s the first ever effort to document wolverine distribution, genetic profile and numbers across the species range in the lower 48,” said Bob Inman, Montana Fish, Wildlife and Parks carnivore-furbearer coordinator.
Called the Western States Wolverine Conservation Program, the project uses grid cells mapped over wolverine habitat across the four states. The states partnered with the U.S. Forest Service, U.S. Fish and Wildlife Service, National Park Service, Northern Arapaho, Eastern Shoshone, and the Confederated Salish and Kootenai tribes, and the University of Montana, Montana State University and Colorado State University, raising nearly $1 million to place bait stations with genetics-gathering hair traps in 180 cells.
The data will provide a baseline inventory, or snapshot in time, of current wolverine distribution and genetics comparable in the future to examine population trends.
“We need information and the truth is there really isn’t a solid plan other than the wolverines documented so far,” said Justin Gude, FWP wildlife division chief of research. “There have been lots of efforts and lots of data sets once studies have ended, but we’re looking for the bigger picture.”
Gude applauded the teamwork it took to coordinate the project and emphasized the importance of looking for opportunities to continue coordinating in the future.
Wyoming began a pilot project last winter and started sampling the southern portion of its cells this winter. Montana, Idaho, Washington and the northern Wyoming cells will all be stationed next winter.
Wolverines were considered for listing under the Endangered Species Act in 2014 due to predicted declines in high mountain snowpack from climate change and habitat fragmentation isolating small populations. In its decision not to list, U.S. Fish and Wildlife Service noted that future impacts on wolverines from climate change were not certain.
“The goal of management is to implement conservation so listing isn’t necessary,” said Bob Lanka, biologist for Wyoming Game and Fish. “In order to get that -- we think this’ll be the impact of climate change and think they’ll decline -- it’s really hard to think about that and actually do some experimental research without a baseline.”
Wyoming’s Legislature set aside special funding for nongame wildlife work and the wolverine project secured a portion, Lanka said, adding that the project overall has been pretty successful at finding grant funding.
“When the wolverine was petitioned under the ESA, the states said we don’t agree with the listing decision’s rational,” he said. “They are a state-managed wildlife species and states can do a good job managing for the foreseeable future. That’s when the states got together and committed to doing something like this because we all have a responsibility.”
The project will benefit managers both in terms of distribution and genetic data, but organizers believe it can inform conservation decisions about connectivity between core habitats, such as conservation easements and development planning. The project may also generate an estimated population size, although with less precision than other data. The current estimate of less than 300 animals in the lower 48 is based on known habitat and home range modeling.
“It’s what you have to do with an animal like this that’s so wide ranging and can move so far with huge home ranges and massive landscapes,” said Rex Sallabanks, Idaho Fish and Game Wildlife Diversity Program manager. “You can’t get a good perspective without a study of this unprecedented scale and this magnitude -- it’s really groundbreaking.”
Surveying the grid cells means first accessing them. Many of the cells fall in remote locations including some wilderness areas, which present logistical challenges. While funding is secured for the 180 cells, organizers are not opposed to including additional cells for conservation groups interested in participating.
“I think this is a great project for citizen science. There is something about wolverines and bait stations that lends itself very well to someone passionate about the resource and has the backcountry skiing experience,” Sallabanks said.
“We have this base set of cells, so anything we can add externally to that we’d love to do whether with the help of trappers or NGOs,” Inman said.
Based on the data currently available, Inman suspects most suitable habitat in Montana and Idaho likely has wolverines. Wyoming and Washington are less certain, he said.
Although the researchers cautioned that potentially transplanting wolverines is outside the prevue of the baseline study, they acknowledge that it is a necessary first step to informing any future transplant discussions.
While currently absent of wolverines, Colorado’s high elevation could roughly double the amount of suitable habitat south of Canada, Inman said. The species’ nature does not conflict with ranching as some predators do, but uncertainly about how a transplant would be handled under a potential ESA listing has stifled the conversations thus far, he added.
“You have these islands of habitat that might hold two females, and that may not be any different than 500 years ago,” Inman said. “Before we started we sat down and asked, ‘What should we do to make sure wolverines are around 100 years from now?’ It’s exciting and a great step in the right direction to be working together for a valuable piece of information to help conserve wolverines.”