Gaspésie National Park in Quebec is well-known for its beautiful views of the mountains and diverse wildlife. Skiers and hikers might even catch a glimpse of the iconic woodland caribou, featured prominently on Canada’s 25-cent coins. But it turns out that what may seem like harmless encounters with wildlife are actually a catalyst for caribou endangerment.

A recent paper in the journal Biological Conservation studied the response of Atlantic-Gaspésie mountain caribou (an endangered population of woodland caribou) to backcountry skiers in the Gaspésie. It suggests that even a relatively subtle human activity, like skiing, can contribute to the mass decline of these animals. In fact, this herd of caribou could vanish from the area within two decades if it isn’t properly protected, lead author Martin-Hugues St-Laurent told me.

While caribou are under threat across Canada, this specific herd is the only population that exists south of the St. Lawrence River, according to St-Laurent, a professor of animal ecology at the Université du Québec à Rimouski. In the past 30 years, the population has shrunk 63 percent because of increased predation by coyotes and black bears. St-Laurent estimates there are only around 70 individuals left.

Caribou in the Gaspésie. Image: Chris Johnson

In this study, he and his team used GPS collars to monitor the movements of Gaspésie caribou across a portion of their range for 2.5 years. They found these caribou moved away from the ski area for approximately 42 hours after encountering skiers, and only returned when they felt the humans had left. The problem is the caribou are moving to lower elevations, where they’re more likely to encounter predators.

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“People are saying, ‘I was out skiing and I saw a caribou, so caribou are not avoiding skiers.’ But that’s not the truth,” said St-Laurent. “We are seeing the same pattern: skiers are there, caribou are there, but after a couple of hours the caribou are leaving. When there are no skiers, the caribou come back.”

Image: Claude Isabel

St-Laurent said that in the last 35 years an “ecological trap” has emerged. There’s an abundance of predators in the valleys, like coyotes and black bears, he explained, and this has forced caribou to stick to the mountain tops—where they will find skiers.

“By responding to skiers, the animals are going to lower elevations, where the probability of encountering coyotes is higher than on the summits,” said St-Laurent.

Image: Denis Desjardins

St-Laurent said that the head office of the Gaspésie National Park is considering restricting access by hikers and skiers when caribou are on the land. The park’s governing body, la Société des établissements de plein air du Québec, has a conservation strategy for caribou, which includes moderating the access to certain mountains.

“The additional pressure that skiers are putting on caribou is [not negligible],” said St-Laurent. “If we are losing one or two females every year, in 20 years there [will be] no more caribou out there.”