They tested the DNA and discovered that a large number of black and grizzly bears were using the crossings.

Sawaya and his colleagues used strands of barbed wire to collect thousands of bear hair samples both in and around 20 crossings in the Bow Valley and in the surrounding area between 20. “Those concerns should no longer be what hold people back.” “We’ve given enough evidence now to show that they work,” he added. Sawaya said the results of the study should put those doubts to rest. Because of that and the high cost, some people have questioned whether the crossings are worth it and whether more such structures should be built in other parks. Initially, grizzly bears were reluctant to use the crossings – it took five years for the bears to gradually get used to them. The crossings are used by a range of wildlife, including wolves, elk, moose, deer, bighorn sheep, coyotes, wolverines, lynx, and cougars. Sawaya said it typically costs $2 million to $4 million to build and landscape an overpass crossing, although the underpasses typically cost less than a tenth of that. Over the course of three decades, 44 wildlife crossings, including 38 underpasses and six overpasses, were built across the highway. “It was a huge safety problem,” Sawaya said in a phone interview. Subsequently, fencing was added on both sides of the highway to reduce collisions between vehicles and wildlife. While the analysis couldn’t determine whether crossing the highway made animals more successful breeders, at first glance it seemed that might be the case, the paper said.Īccording to Parks Canada, the 83 kilometres of the Trans-Canada Highway passing through Banff were upgraded to a four-lane divided highway from two lanes in 1981. That male, he observed, “certainly has found that he has increased his own breeding opportunities by having access to both sides of the highway.” One black bear male in the study, mated with at least five different females and fathered at least 11 offspring while crossing back and forth, said Michael Sawaya, lead author of the study published Tuesday in the journal Proceedings of the Royal Society B. Now, a new genetic analysis of bear hair samples by researchers at Montana State University shows the bears are indeed crossing the highway to mate with bears on the other side. That, in turn, could lead to isolation and inbreeding.Īnd while Parks Canada found that the fencing and 44 crossings did reduce wildlife collisions by 80 per cent, it wasn’t clear whether animals used the crossings to find mates. Scientists had previously been concerned that the highway, which is fenced on both sides through Banff National Park , might block animals from breeding with others of their species on the other side of the highway.

Grizzly and black bears are looking for love on both sides of the Trans-Canada Highway, and using wildlife crossings to rendezvous with members of the opposite sex, a new study confirms. It took grizzlies about five years to get used to the wildlife crossings and begin using them regularly.

Underpass wildlife crossing