British Columbia

Low salmon stocks cause increased interactions between bears and humans: study

A B.C. research study has found a 50-per-cent drop in salmon stocks led to an average 20-per-cent increase in bears being killed due to interactions with humans.

Study also found that hunting, killing problem bears had no effect on the frequency of human-bear conflicts

A grizzly bear is seen fishing for salmon along the Atnarko river in Tweedsmuir Provincial Park near Bella Coola, B.C. Saturday, Sept 11, 2010. A B.C. study has found a link between the availability of salmon for bears, and the frequency of interactions between bears and humans. (The Canadian Press)

 Low salmon stocks in B.C. waterways cause an increase in conflicts between humans and bears, and killing problem bears doesn't actually reduce the frequency of human-bear interactions.

That's according to a new study by B.C. researchers — published in Scientific Reports — which looked at 35 years of data relating to conflicts between humans and grizzly bears in B.C.

For bear populations that feed on spawning salmon, the study found that for every 50-per-cent decrease in salmon populations, the annual number of bears killed per square kilometre increased by an average of 20 per cent.

Sam Craven of Athens, Ga., left, moves away from one of two young grizzly bears that were feeding on salmon at Bird Creek along the Seward Highway in Alaska, Friday, July 28, 2006. (AP)

"We might expect that in any areas if you have a food-poor year, bears — or again any carnivore — might be forced to take greater risks to obtain nourishment and this might bring them closer to humans," said the study's lead author Kyle Artelle, a biologist with the Raincoast Conservation Foundation and a PhD candidate at Simon Fraser University.

"And coming closer to humans of course comes with a lot of risks for humans and bears alike."

Hunting, killing problem bears 

The study found that 82 per cent of conflicts occurred when the bears were preparing for hibernation — a time when the animals have to consume a lot of food.

The study also found that killing problem bears did not decrease the number of interactions between bears and humans, and hunting had no overall effect.

"Hunting kills have absolutely no measurable impact across these 35 years of data on conflict … and the same with management kills of bears," Artelle said.

"So killing problem individuals doesn't reduce overall patterns of conflict in areas across the province."

Artelle said the results of the study could be used to stress the importance of people preventing conflicts with these wild animals by keeping their garbage well managed, being cautious in areas where they might encounter bears and having enough fish in the first place.

"'We could use that information to better predict when bear-human conflict might be particularly severe. So if you know there is a bad salmon year coming, you might be able to predict conflicts are going to be worse in areas where bears are reliant on that salmon."

With files from CBC's The Early Edition

To hear the full story listen to the audio labelled: Low salmon stocks lead to more conflicts between bears and humans, study suggests