Recreational trails disturb grizzly bears and wolves more than expected

A new study from the University of Alberta shows that human recreation on mountain trails is driving grizzly bears and wolves out of their natural habitats, even if the trails are hundreds of meters apart. This research aims to ensure that recreationalists and wildlife can coexist, particularly in the busy Bow River Valley, which has long served as a natural corridor connecting the prairie and the Continental Divide. , highlighting the need for more effective planning.

The research was led by Peter Thompson, a former postdoctoral fellow of the Colleen Cassady St. Clair Professor in the School of Biological Sciences. Thompson and St. Clair worked with biologists from Parks Canada and Parks Alberta to place camera traps at more than 1,600 locations in the Bow River Valley and adjacent mountain parks from 2007 to 2022.

In the study, published in the Journal of Applied Ecology, researchers analyzed more than 1 million images of humans and tens of thousands of images of bears and wolves to detect different species in areas with different levels of human use. We compared the situations.

Thompson used statistical models to estimate human use across the landscape and then determine the likelihood of grizzly bears and wolves being present in different areas.

Not surprisingly, almost all large carnivores will completely avoid areas immediately adjacent to the busiest trails. However, this migration effect appeared to persist over long distances.

Trails that are not used at all by humans have little impact on wildlife, but only half of the grizzly bears studied venture within 300 meters of trails that are heavily used by humans. This effect was more pronounced in wary wolves, whose comfort radius extended up to 600 meters from the busiest roads. Thompson says these “spheres of influence” caused by people are much larger than previously thought.

“We initially thought that bears might use hiking trails as an efficient route when humans weren’t around, but in reality, bears avoid these areas altogether,” said the researcher, now at Simon Fraser University. says Thompson, a postdoctoral researcher at . “Our results show that human recreation has significant impacts on wildlife, significantly influencing wildlife behavior even hundreds of meters away from trails.”

Thompson said the findings will help land managers in the Bow River Valley create safe and quiet areas for grizzly bears, wolves and other large carnivores that require undisturbed habitat for migration. He added that he was looking forward to it.

“When trails become crowded, people may not realize how much they are disrupting wildlife movement and habitat safety,” he explains.

St. Clair, Thompson’s former boss, emphasizes that park planning in Alberta, and particularly in the Canmore region, where this study was based, is increasingly focused on managing human-wildlife interactions. .

“Wolves are even more influenced by human recreation than grizzly bears, and are active year-round to coincide with their winter recreational activities,” Professor St Clair says. “This study highlights the critical need to manage human use in ways that allow people to share landscapes with these wary predators.”