The Bear Maximum

Most people want to avoid bears. Sarah Rovang, on the other hand, wants to attract as many as she can find. The graduate student with the University of Alberta's Department of Renewable Resources is developing better methods for understanding the size, health and status of bear populations in a given area.

To do so, Rovang draws bears to a specific zone using a pungent mixture of rancid beef blood, canola oil, logs and moss. The area is marked off with a single strand of barbed wire. The barbed wire is positioned low enough for the bear to step over, but catches a bit of hair as the bear passes by. This hair, often from the inner and outer coat, leaves behind a calling card, of sorts—their DNA. Analysis in a lab can reveal a rich source of data on gender, lineage and overall well-being.

"The DNA can be used to identify specific bears so we can get a better idea of how many are roaming in a given area," says Rovang. "Using the samples, we can also detect certain hormones, such as those related to stress, and learn about factors impacting their health."

With grizzly bears now listed as a threatened species, it's more important than ever for wildlife stewards and other researchers to have cost-effective ways of taking stock of bear populations. One advantage of Rovang's approach is that her field study ran for four months starting in spring 2011, nearly two months longer than previous studies, resulting in more than 650 hair samples.

"To take conservation action, we need to know what the local population is doing, so it's important to find responsible, cost-effective ways for long-term monitoring. A network of fixed sample plots could be one way to do that," says Rovang.

Rovang's work is supervised by Scott Nielsen and funded by grants from the Natural Sciences and Engineering Research Council of Canada and other partners. Her future research directions will look into identifying the eastern range of the Rocky Mountain grizzly bear.