New research into wolverines in the Canadian Rockies suggests landscape development may be placing considerable stress on the animals, causing them to alter their hunting behaviour.
Researchers with Alberta Innovates studied wolverines in the Kananaskis, Banff, and Willmore Wilderness Park regions and discovered strong variations in animal behaviour depending on the level of protected versus developed habitat.
"There's something about developed landscapes that wolverines perceive as risky. We don't know what that is yet, but we're trying to figure that out," said senior research scientist Jason Fisher.
The wolverine's wildlife status is listed as "special concern," in Canada, and over the past century, wolverines have lost roughly 40 per cent of their North American habitat, he said.
The bait experiment
The iconic predators are known for their strong jaws and sharp teeth, but little is actually known about their behaviour patterns, Fisher said.
In order to study this, the researchers designed an experiment to "take advantage of a wolverine fact, and that is that wolverines are always hungry," said Fisher.
In winter, the animals patrol huge territories up to 1,000 km² to find carcasses.
"We oblige that by nailing a lovely, large beaver carcass to a tree," said Fisher.
Scientists then wrapped the tree with barb wire and placed a camera triggered by infrared movement sensors.
When a patrolling wolverine climbs the tree for its free meal, the barbed wire snags a DNA hair sample, which researchers later analyze.
The camera also captures each wolverine's unique chest markings for future identification and records the animals' predatory behaviour.
Camera reveals all
To the surprise of the researchers, there were wide variations in how the animals approached the bait.
"Some wolverines were downright casual," said Fisher.
"They get to a site, take their time to check it out, lounge about, sometimes even play-fight with their siblings if they're kids."
"At other sites, wolverines didn't trust the bait at all. They just came into the camera and left without a second glance."
Upon analysing the data, researchers concluded that "loungers" were far more likely to be found in protected parks, whereas the cautious "cat burglars" were found in areas with developed road networks and concentrated petroleum or forest harvesting activity.
Fisher plans to continue his work in Alberta and B.C. to map out wolverine habitat and get a better idea of how stable their populations are.