14 Aug 2013:
Bears Using Wildlife Corridors
In Canadian Park, Genetic Tests Show
Genetic testing has revealed that bears in Canada’s Banff National Park routinely cross the bridges and underpasses along the Trans-Canada Highway
, evidence that the ecological corridors provide safe
A grizzly passes through a Banff underpass
passage along a busy roadway that otherwise threatens to fragment wildlife habitat
. Using 420 wire snag “hair traps” and 497 rub trees at 20 crossings to collect hair from passing bears, researchers from Montana State University determined that 15 individual grizzly bears and 17 individual black bears used the passages over a three-year period. According to researchers, those accounted for about 20 percent of the park’s bear populations, suggesting that the passageways are providing enough connectivity to maintain a healthy ecosystem for the bears and other large mammals. Twenty-five passages were installed during the 1990s
when the government widened the highway that crosses the country, including a 100-mile stretch that bisects Banff. “We knew that bears used the crossings, we just didn’t know how many,” said Tony Clevenger, a wildlife biologist and one of the authors of the study published in the journal Conservation Biology
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