CANMORE – Wolverines are facing increasing pressure from development and human activity as wilderness continues to shrink.
Researchers are just beginning to understand the distribution, population genetics and land use of the solitary at-risk species, but little is known about the exact locations of maternal denning sites.
Canmore-based wildlife ecologist Nikki Heim believes it’s important to gather that information, noting protections at maternity denning locations, like for many wildlife species, are considered critical for conservation of wolverines.
“There isn’t a lot of information out there on wolverine reproductive dens and very, very few have been identified in Canada,” she said.
“Knowing where the dens are could be a significant first step in protecting these critical areas in which they reside.”
The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) highlights the importance of wolverine denning sites.
The versatile predators and scavengers breed between late April and early September, but embryos do not implant until January. Sometime between late February and mid-April, females give birth to anywhere from one to three or four kits.
The young nurse for eight to 10 weeks before leaving the den, but they stay with their mother throughout summer, fall and winter learning to hunt before dispersing the following spring.
Based on some work already underway in the Kootenay region of British Columbia, Heim wanted to test the use of low-noise drones as a non-invasive approach to investigating and locating wolverine maternal dens in the Canadian Rocky Mountains.
Unlike in the past, when snowmobiles or helicopters may have been used for wolverine research, Heim said new drone technology is offering researchers an alternative to survey high probability den areas in a stealth manner not possible previously.
Working with a drone company operator, Alex Taylor, they came up with a plan for the research using established drone protocols for low-noise and not flying lower than 100 metres.
“To be completely honest, as a wildlife biologist myself, when people started using drones for wildlife, I was like ‘I don’t know about this’ and I had a lot of reservations, but it’s more disturbance for me skiing in to find that den,” Heim said.
“It’s kind of a trade-off. If we want to identify these locations to protect wolverines, what can we do that causes the minimal amount of disturbance – and drones are definitely the lesser.”
Heim pinned her hopes on an area near Talus Lodge, a commercial recreational operation situated in an alpine environment just west of Kananaskis Country in Alberta and to the south of Mount Assiniboine Provincial Park in B.C.
Every year, the operators of the backcountry skiing and hiking lodge, Canmore couple Sara Renner and Thomas Grandi, report wolverine sightings and tracks – both singles and pairs.
In addition, the rugged landscape had all the habitat characteristics Heim was looking for to make it easier to potentially find wolverines – north facing slopes, large talus and boulders, persistent spring snowpacks and proximity to avalanche paths.
Heim said there was also evidence in the region of an abundant marmot colony, which is a preferred prey by female wolverine with young.
“When she comes out of her den with kits, she really needs to have access to a good food source for the months while they’re growing,” she said.
“They seem to be in areas where there is a strong marmot colony, which isn’t surprising, because that’s kind of good bang for your buck. Scavenging works, but it’s not as easy.”
Working in cooperation with Talus Lodge, Heim and Taylor did surveys over two trips with the support of Alpine Helicopters to get them there – one in mid-March for reconnaissance and to test methodology, and the second in mid-April to look for tracks of wolverines to and from potential wolverine denning sites.
“Basically what you’re doing is you’re flying a drone over an area you suspect that there might be a wolverine den,” Heim said. “You’re looking for tracks that go to one single point – back in and out.”
The day before the second survey, Renner and Grandi let Heim know that they had seen fresh wolverine tracks.
“If you can’t be up there all the time, it was so helpful having those partners out there saying ‘hey, I’ve seen lots of tracks,’ ” Heim said. “It was so advantageous they saw fresh tracks.”
Heim couldn’t believe her luck, when fresh wolverine tracks were detected on April 15 – a single adult wolverine track and two smaller juvenile tracks, suggesting a family group.
“There’s a lot of ifs in detecting a den site, so this was totally amazing, particularly because I’ve also never tried this before,” she said.
“I felt like I was searching for a needle in a haystack, even though I’ve narrowed down a part of the haystack.”
Heim will head into the area again this summer to confirm 100 per cent it is a maternal den site.
“I’ll go back when they’re gone and have a look around – so look for hair, they’ll kind of soften the area,” she said.
If she confirms it is a den, Heim will set up remote cameras to determine if wolverines come back to the same denning site in future.
“We could then see if she’s using it year after year and Talus is totally onboard to help us do that,” she said.
“The term is site fidelity and some researches don’t think they do use the same den and some are starting to find more evidence that they do.”
Heim hopes that increased knowledge of wolverine den locations will allow land managers, commercial operators, and recreationalists to avoid these sensitive areas, and thus reduce the potential negative impacts of human disturbance.
“We’ve had discussions with Talus about where the den is and long-term monitoring for continued use and revaluation of where they are skiing,” she said.
Renner and Grandi are more than willing to continue working with Heim and to do whatever they can to adjust their backcountry operation to protect wolverines.
When they began operating Talus in 2018, Renner said the first step was to reach out to their neighbours, including the Ktunaxa Indigenous peoples as well as hunting, forestry and mining industries.
“But we knew our closest, closest neighbour was the wolverine because we had sightings of them and had seen tracks of them,” she said.
“We knew it would be very valuable for us, if they are in fact denning in the area, that we know where to stay away from and which times,” she added.
“I hope through Nikki’s advice that we’ll really be able give that wolverine a chance to be a good mama.”
From the beginning, Renner said the ski product at Talus Lodge has been defined as: “We don’t count vertical feet, we count wolverine tracks”.
Renner said it is so important to move through the wilderness in the quietest and most respectful way possible.
“We really feel like we are in a wildlife corridor and it’s a privilege to be there, it’s not our right,” Renner said.
“This space belongs to the Ktunaxa, to the wolverines and the grizzly bears.”
Heim said the plan is to continue to use drones to find other denning sites throughout the Rocky Mountains of Alberta and B.C. to help guide management and related landscape-scale conservation for wolverines.
She hopes the partnership at Talus Lodge can be used as an example to encourage other mountain operators and recreational enthusiasts to take individual actions to minimize disturbance of critical wolverine habitat, such as maternal dens.
“For a wolverine to be in that area so often, and then consider having her kits there, is a testament to having an operation that is low intensity. It shows that you can strike that balance,” Heim said.
“In the conservation world these days, I feel like it’s hard to find a win, and it might be a small one, but working with Talus Lodge and how they’re more than happy to mitigate the way they need to, is so great.”
Wolverines are considered a species of concern in Alberta and B.C. They require large swaths of territory to roam, naturally occur in low numbers, reproduce very slowly and survival rate is low.
Their struggles are made even tougher because they are sensitive to human pressures such as various forms of recreation, like skiing and snowmobiling, industrial development like logging, mining and oil and gas, and transportation corridors that bisect their home ranges.
"They are identified as a species whose numbers are decreasing," Heim said. "I think that's why finding out where some of these den sites are is even that much more critical."
Wolverine sights or tracks can be reported online through wolverinewatch.org, which is a central repository for wolverine sightings and research in western Canada.