British Columbia

Climate change could harm relationships between predator and prey, says researcher

A new UBC study has found that extended summers and shortened winters can alter the relationship between great horned owls and the snowshoe hare, leading to the extinction of both.

Shortening and lengthening of seasons could upset the balance between co-dependent species, says study

Climate change could drive the great horned owl and snowshoe hare populations to extinction in Canada's boreal forests, according to a UBC Okanagan researcher. (Debra Beaton)

Climate change could negatively impact the relationship between predator and prey relationships, according to a UBC Okanagan study.

UBC mathematics researcher Rebecca Tyson studied the relationship between the predatory great horned owl and its prey, the snowshoe hare, and found that warming temperatures could drive the hare, and ultimately the owl, into extinction.

"It looks as though just by increasing the length of the summer relative to the lengths of the winter, that a previously stable predator-prey relationship could become unstable — driving one species extinct," she told host Audrey McKinnon on CBC's Radio West.

"They can't coexist if the summer is too long," she said.

According to Tyson, in the boreal forests great horned owls feed heavily on snowshoe hares in both the summer and winter.

"The hare is considered a keystone species because it's the biggest meal up there, especially in the wintertime." she said.

The hare is considered a keystone species, according to Tyson, as it's one of the largest meals in the boreal forests. (Yukon government)

But if the length of the summer increases, the owls could drive the hare population to near extinction, meaning that animals that depend on hares throughout the wintertime — when food is much more scarce — would be extremely vulnerable.

"The great horned owl population wouldn't make it through the winter," she said. "And there are several populations in the North that depend on the hare."

Other species, like the lynx, would also be vulnerable if the hare population collapses in the region, said Tyson.

"There's a big web involved that eventually needs to be looked at," she said.

While the population shift would take time, Tyson says it would require human intervention to keep the populations healthy.

"It looks as though climate change is happening so quickly that the more complex species can't evolve fast enough," she said.

With files from CBC's Radio West

To listen to the full interview, click on the audio labelled: Climate change could harm relationships between predator and prey, says researcher