Could roadkill stop the spring kill of cattle by Alberta's grizzly bear population?
That was the question behind an analysis of a 15-year provincial project, undertaken by Andrea Morehouse, a wildlife biologist with the University of Alberta.
The study, known as the intercept feeding program, ran from 1998 to 2013 in southwestern Alberta.
"The goal of the program was to reduce spring incidents of grizzly bears killing livestock," Morehouse said on the Calgary Eyeopener.
In an effort to alter the grizzlies' behaviour pattern, roadkill ungulates were collected during the winter, then dropped by a helicopter at a dozen remote sites.
The thinking behind the provincial project was straightforward enough.
Morehouse said it was done "with the hope that when bears emerged from hibernation, they would feed on these piles of roadkill as opposed to going to lower elevation areas where vegetation was beginning to green up, but cattle were calving."
Morehouse devised a unique methodology in order to monitor the bears in her study
"We wanted to identify how many bears were actually using these sites and to do that we collected DNA samples from those bears," she said.
At each site, there would be a pile of roadkill and they would select "two trees that were near that site and we sprayed those trees with WD-40 and wrapped them in barbed wire.
"For whatever reason, that I don't know, WD-40 elicits a rub response from bears and so they would come into the sites, feed on the roadkill and then rub on these artificial rub trees that we had collected."
The team would then collect the hair samples and extract the DNA to identify how many bears were using the sites.
In addition to the greased up trees, the researchers worked with Fish and Wildlife officers and residents to collect hair samples from conflict sites to identify which bears were involved.
The number of events and the costs were also tracked.
The results? It turns out the grizzlies ate the roadkill. And then when spring calving season arrived, they ate cattle — just as many as they ever did.
As to reasons why, she can only speculate, including more bears.
She added that researchers are seeing these sorts of incidents happening farther and farther east, which would involve grizzlies with no access to the roadkill dropped at the sites in the southwest.
"There's of course, changes in natural food availability or natural food abundance and weather that could have also played a role in this, but we didn't monitor those things directly in this project," said Morehouse.
After suspending the project for several years, the data has revealed no measurable change in the bears' behavior. At a cost of $44,000 a year, it's difficult to make a case to continue it, the biologist said.
"I can't speak for the province, but it's my understanding that it's unlikely that they will be re-instituting the program," she said.
