Spotting bears in B.C.'s backcountry is fairly routine for Mike Robertson.

Spotting a black bear feasting on another bear, however, is not.

"I tell ya, I've seen a lot of bears, a lot of wildlife over the years, but that sent chills down my bones," Robertson said.

The policy adviser works with the Cheslatta Carrier Nation, south of Burns Lake, B.C. He's been doing regular helicopter flyovers of areas charred by this summer's wildfires to get a sense of the damage.

This week, Robertson saw two bears on the shoreline of Cheslatta Lake. He thought they were both dead, before the helicopter dipped closer for a better look.

The crew was horrified when they realized what they were actually seeing — a black bear hunched over the carcass of another bear, jaws bloodied.

Disturbed by the helicopter, the animal looked up and bared its teeth at the aircraft.

"That old boy was very, very, angry and protective of his kill," Robertson said.

Seasonal aggression

The B.C. Conservation Officer Service says bears are often more aggressive during the fall season as they prepare for hibernation and that it's not entirely unusual for the animals to eat their own kind.

But Robertson believes there's been an increase in strange behaviour in light of the province's worst wildfire season since record-keeping began.

"They're definitely under stress because of the fires, the lack of food," he said. "A lot of their den sites have been totally scorched."

Ash covers the ground in an area burned by the Shovel Lake wildfire, near Fort Fraser, B.C., in late August. The 2018 wildfire season was the province's most destructive on record. (Darryl Dyck/Canadian Press)

'Bear-eat-bear world'

Other bear populations have been known to resort to cannibalism when the going gets tough.

Up to eight cases of male polar bears preying on cubs and other bears were reported in Manitoba over the fall of 2009. Officials suspected climate change and diminishing habitat to be the cause.

Four years later, a group of hikers found a grizzly bear feeding on a black bear along a trail in Banff, Alta. Park rangers there agreed it wasn't out of the ordinary as the animals prepare for winter — but it is a rare sight.

The B.C. Conservation Officer Service says it's not entirely unusual for bears to eat their own kind. (Dan Ralfa/Parks Canada)

"We know it's a dog-eat-dog world out there, but we're finding out it's a bear-eat-bear world as well," Steve Michel, a human-wildlife conflict specialist with Banff National Park, said at the time.

With files from Audrey McKinnon, CBC's Daybreak North and the Canadian Press

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