Pronghorn using wildlife overpasses

Nov 11, 2013

Conservationists are relieved that migrating animals are using the recently-built overpasses on U-S Highway 191 near Pinedale. The highway cuts across major wildlife migration routes, and vehicle collisions with animals have been a problem in the area for years.

The Wyoming Department of Transportation finished six underpasses and two overpasses for the wildlife last year, inspired by similar structures in Banff National Park. They were the first ever built for pronghorn antelope, which can't jump roadside fences, and they avoid enclosed spaces. 

Tall fences discourage the migrating animals from trying to walk on the highway, and funnel them toward the over- and underpasses.

John Lund is the Department of Game and Fish Regional Wildlife Supervisor in Pinedale. He says the structures also have wildlife-friendly gates that are sometimes closed to keep grazing cattle from crossing the highway.

“Even though it functions to keep cattle out, deer and antelope can easily navigate those,” says Lund. “They’re low enough a deer can jump right over the top of them, and the bottom fence line is high enough that antelope can crawl right underneath them.”

Jon Beckmann of the Wildlife Conservation Society says he was relieved to find that – although the pronghorns approached the overpasses with trepidation at first – they are using the structures to cross the highway. Beckmann says it’s a “win-win” for wildlife and motorists.

“ People can continue to move up and down the roadway more safely, and animals can move across the landscape between their winter and summer areas safely as well,” Beckmann says.

Beckmann says experts are still collecting data on how many animals cross the overpasses, and how many animal-vehicle collisions still happen in the area.