Wildlife mortality hotspots, connectivity along U.S. Highway 287

Prior to the Madison County Planning Board meeting on April 24, Renee Callahan from the Center for Large Landscape Conservation gave a presentation about the effects of roads on wildlife.

“Roads are one of the most disruptive forces on the planet,” Callahan said. “Nationally, the number of overall collisions on roadways have stayed stable over the last 15 years, but collisions with animals are trending upward.”

Callahan said there are proven solutions, including animal overpasses or under the highway crossings with appropriate fencing.

Wildlife are not under the jurisdiction of the transportation agencies – that, combined with a lack of awareness about the problem and the costs associated with remedies, are the reasons there is not more being done to mitigate the issue of vehicles colliding with wildlife, Callahan said.

In 2012, the Western Transportation Institute at Montana State University and the Craighead Institute started a project to look at the effects of U.S. Highway 287 and MT Highway 87 in the Madison Valley on road related wildlife mortality and movement patterns, said Lance Craighead of the Craighead Institute.

At the April 24 meeting, Craighead presented the findings of the project, which was released in November 2016 by the Montana Department of Transportation.

“Pretty much the whole highway is highly used by animals, and they’re getting hit all over the place,” Craighead said.

According to a project summary report, there is a growing body of data documenting animal movement across the highway by elk, grizzly bear, wolverine and other species; the barrier effect of the highway and road related wildlife mortality patterns were poorly understood prior to the study.

“From April 2012 to April 2014, collection was completed of carcass and live animal observation data three days per week, year round, in the study area,” the summary states. “Remote camera data was recorded at 11 culverts and bridges throughout the study area to assess wildlife use of existing underpasses and opportunistically collected snow tracking data to assess patterns of wildlife crossings.”

Craighead said the elk data lined up – where the majority of elk were spotted or tracked crossing the highway, was also where the most carcasses were observed.

Madison Valley Planning Board President John Fountain asked if more collisions occur at night.

Craighead said that data was not parceled out in the study, but other studies have shown that more wildlife-vehicle collisions do occur in the dark.



In neighboring states like Wyoming and Idaho, federal dollars have funded 80 percent of projects to construct wildlife overpasses, Callahan said. One determining factor in receiving federal dollars, however, is connectivity to land that will not be subdivided in the future.

“You don’t want to funnel animals (across a highway) onto private land that might get sold or subdivided,” Callahan said.

Fountain pointed out the South Madison Valley, where many elk carcasses were observed, and where elk cross the highway to move between the Madison and Gravelly mountain ranges, may be a good place for a wildlife overpass.

“There are lots of elk, public land and conservation easements,” Fountain said. “Between the wilderness and the biggest bunch of conservation easements anywhere, we could build something down there.”

Based on the data analyzed in the study, Craighead said a few sections of road stand as prime locations to mitigate wildlife-vehicle collisions.

“The importance of the Madison Valley as winter range for ungulates will remain the same or perhaps increase in the future given the permanent habitat protections that exist in the form of government lands and conservation easements on private lands,” the summary states. “Traffic will likely increase in the future.”

Craighead said any “accommodation efforts” would be most effective if they addressed winter conditions, focusing on elk.

“Crossing structures of the appropriate type and size, in combination with wildlife exclusionary fencing, would likely be used by thousands of elk every winter and may greatly reduce carcasses in that area,” the summary states.

No Comments.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>