This grizzly bear in Canada’s Banff National Park isn’t ambling along just any path—it’s walking over the Trans-Canada Highway on a wildlife crossing, a semi-natural bridge that provides animals secure passage across the busy, four-lane highway. The park now has 24 such bridges and tunnels. And grizzlies aren’t the only beasts that walk on the safe side: Since 1996, 10 large-mammal species (including elk, cougar, and wolf) have used the crossings more than 95,000 times. The structures prevent animals from becoming roadkill and also connect habitat divided by roadways, which can help boost genetic diversity. Wildlife crossings are increasingly popular in North America: Their numbers doubled in the last decade, and more than 600 now dot the continent.

Story by Alisa Opar. This article originally appeared in Plenty in February 2008. This story was published on

Copyright Environ Press 2008

Grizzly crossing
Semi-natural bridges provide animals secure passage across busy highways.