Human development restricts wildlife movement: study
Thursday, Mar 01, 2018 06:00 am
It’s long been known that human-modified landscapes impact how animals travel in the Bow Valley, but a new study has confirmed it also affects how far they travel.
According to a global study which included 803 individual animals across 57 species, mammals across the world move distances that are about two to three times shorter on average in areas of high human activity than they do in wilder places.
“People have studied animal movement for many, many years, but this study is really interesting because it’s the first time data on so many different species across the world has been brought together,” said Dr. Aerin Jacob, a conservation scientist with Yellowstone to Yukon Conservation Initiative (Y2Y).
Published in the Journal of Science, the findings indicate that regardless of the species or the location, human development reduces long distance movements, such as migration.
“In some ways our study is unsurprising because it’s predicted completely by the principals of island biogeography theory, which we’ve known about for 40 years. But what’s so striking is that it’s truly this consistent global signature on everything from a possum to an elephant,” said Dr. Mark Hebblewhite, one of the coauthors of the study and a wildlife biology professor with the University of Montana.
Locally, he pointed to the decline in migration of elk and wolves in the Bow Valley as a prime example.
“Most of the elk in Banff don’t live in the Bow Valley, they come from Ya Ha Tinda, the winter range that is on the northeast boundary of the national park on the Red Deer River,” said Hebblewhite, who is also a board member with Y2Y.
“Twenty years ago there were 2,000 elk at Ya Ha Tinda. Ninety per cent of those elk migrated into Banff National Park. Now there’s 500 elk and only 30 per cent of those migrate, so migration allows caribou and elk to achieve higher abundances, have larger population sizes and are less vulnerable to extinction,” said Hebblewhite.
In the case of wolves, he said they’ve also seen wolf movement decline in areas of high human activity.
“When you look at the wolf data from the Bow Valley, even just visually it’s very constrained, they’re hemmed in. They’re stuck between the highway, the railway and the townsite,” said Hebblewhite.
As fewer animals migrate, he said, the risk of inbreeding increases, reducing survial rates.
To reduce the human impact on animals he said it’s important to improve habitat connectivity.