Tracking a wilderness icon
WCS Canada has been tracking wolverines across northern Ontario in an effort to better understand where wolverines live, how many there are, and how they respond to disturbances like logging and roads.
Photo: Susan Morse ©
Wolverines are fascinating animals that have a reputation for being clever, powerful and reclusive. They are very well adapted to life in the north, with snowshoe like feet, thick coats and powerful jaws and long sharp claws for breaking apart frozen carcasses.
Despite this fierce reputation, they also have a sense of play...
And even like to take a swim sometimes!
Photo: Grant DoBel ©
Our work on wolverines started with seven years of aerial surveys across a vast section of the province’s far north that provided new insights into where wolverines were most likely to be in the province.
This map comes from our recent aerial surveys for wolverine tracks - hotter colours indicate places where you're more likely to see a wolverine.
Wolverines once existed throughout the boreal forest in Ontario and the Hudson Bay Lowlands, but human activities and developments in the south have relegated wolverines to remote regions in northwestern Ontario.
Wolverines are now considered a Threatened species in Ontario because scientists believe there are fewer than 1000 left in the province.
To help them recover, the Ontario government has identified the need to learn how many wolverines there are and what can be done to maintain or enlarge the population - especially reproductive females in areas with forestry.
WCS Canada initiated a three-year study in 2018 to address some of these research needs.
Our study takes place around Red Lake, Ontario...
And has three objectives: estimate wolverine abundance in northwestern Ontario; track female habitat use while they are denning; and learn how forestry, mining and climate change affect wolverines.
This information can then be used to better manage the wolverine population and promote population growth.
To count wolverines we need to identify how many unique individuals are in the area.
Run poles are baited with beaver carcasses donated by local trappers. When the wolverine tries to get to the beaver bait, a camera opposite the run pole takes a picture.
This wolverine has teats, meaning she likely has young. That tells us that the habitat in this area is well suited to breeding females, who are a major focus of our project.
Wolverines' unique chest markings help us tell individuals apart.
We provide the ear tags, which also help!
We also collect some hair samples for DNA analysis - more evidence to figure out how many individuals are in the area.
We also count individual wolverines by capturing them live in live traps.
Live trapping powerful wolverines requires sturdy traps. We construct some of these live traps out of logs harvested onsite and carefully assemble them to be strong enough to hold these determined escape artists.
Wolverines are attracted to live traps because of beaver bait inside.
When the wolverine goes in, the field crew is instantaneously alerted by a satellite-trap transmitter.
Wolverines caught in our live traps are carefully sedated, then measured and weighed using vetted and approved protocols. Our first priority is always the safety of the animal and of our specially trained researchers.
We record markings, sex and estimate age and then outfit the animal with a GPS collar and ear tag. The wolverine is then placed back in the trap until the anesthesia wears off, at which point it is released.
Wolverines are usually in a hurry to leave once they wake up!
But sometimes it is not a wolverine that is waiting! This lynx was attracted by a live trap’s bait.
Once we know it is not a wolverine in the trap, the animal is immediately released.
Our live traps and run poles cover an area of ~ 6,000 km². Plenty of space to count a wide ranging and rare species like wolverines!
Over two years, we have identified about 35 wolverines at our run poles and live traps.
Photo: Jerry Lee ©
In addition, our GPS collars have collected nearly 20,000 GPS locations from wolverines, which has given us a much more extensive picture of their movements.
One female wolverine traveled hundreds of kilometers into northern Ontario.
Wolverines need large areas of habitat, which makes them a good indicator species for the health of forest ecosystems.
We have tracked wolverines to 30 kill or foraging sites. Wolverines are considered scavengers, but also hunt small game like beavers and hares.
The reproductive dens we have found, like these two in a tree-root ball and rock crack, allow us to understand how females manage to reproduce in industrialized landscapes.
We even found a wolverine den in a forestry slash pile!
We worked with the Ontario Government, using our data on reproductive female habitat-use during denning to better manage forestry activity in their home ranges.
We've also been tracking wildlife use of forestry roads. In particular, we are interested in how forestry roads affect wolf movement…
…but we get lots of other species on the cameras too.
Local trappers who share our concern for sustaining healthy wildlife populations have been a big help with our research, sharing their deep landscape knowledge and wolverine sightings.
Given the vast size of our research area, we cannot do this work without the cooperation of trappers and Indigenous people who know this land so well.
We will continue to track wolverines across Ontario’s north in an effort to provide recommendations for how the province can ensure their recovery.
We are working closely with provincial authorities and the forestry company operating in the area to make adjustments to forest management based on our results. We will soon be able to provide recommendations for landscape-scale conservation of this sensitive species as well.
Despite some encouraging signs that wolverine populations are growing in Ontario, we need to make sure resource development proceeds in a way that does not hinder recovery.
Photo: Susan Morse ©
Further information on wolverines in lowland boreal forests in Canada (authored by WCS Canada Scientists):
- Wolverine: Ghost of the northern forest
- Studying the elusive wolverine, a threatened species in northern Ontario
- Searching for wolverines in a vast northern wilderness
- Why won't wolverines cross the road?
- Modelling broad-scale wolverine occupancy in a remote boreal region using multi-year aerial survey data
- Temporal patterns of wolverine (Gulo gulo luscus) foraging in the boreal forest
- Roads elicit negative movement and habitat-selection responses by wolverines (Gulo gulo luscus)
- Wolverine habitat selection in response to anthropogenic disturbance in the western Canadian boreal forest
- Distribution of female wolverines relative to snow cover, Alberta, Canada
- Roads, logging, and the large-mammal community of an eastern Canadian boreal forest
- Wolverine, Gulo gulo, home range and denning habitat in lowland boreal forest in Ontario, Canada
- Modeling wolverine occurrence using aerial surveys of tracks in snow
