Wolf culls do nothing to save endangered caribou, study finds

A government-sponsored wolf kill in Western Canada has had “no detectable effect” on reversing the decline of endangered caribou populations, a study says.

Scientists from Raincoast Conservation Foundation and the universities of Alberta, British Columbia and Victoria found statistical flaws in an influential 2019 report supporting a wolf cull.

The new research published in the international journal Biodiversity and Conservation found that addressing potential threats from wolves did not slow the loss of mountain caribou in B.C. and Alberta. Instead, it says factors affecting population decline include loss of habitat to logging, snowpack variation and snowmobiling.

Wolves and caribou have coexisted, interacting as predators and prey, for millennia in western North America, said Chris Darimont, co-author on the study.

But this balance began to tip around the middle of the 20th century when industrial clear-cut logging and oil and gas development took off, said Darimont, who is also a professor at the University of Victoria and science director for Raincoast Conservation Foundation. The cleared land and roads made wolves more efficient predators where they travelled large distances to search for vulnerable prey, he said.

“Despite not preferring caribou, many on average killed more caribou simply because there are more wolves,” he said.

Another factor affecting caribou population is the availability of lichen in old growth forests, which were cut for timber, Darimont said.

The logic behind wolf culls has been “somewhat seductive and compelling,” Darimont said. If you take away most or all of the wolves, the caribou should do better, but data does not support that logic, he added. The researchers found that culling wolves or putting pregnant caribou behind pens was no more effective than doing nothing, he said.