Reconnecting Colorado: How wildlife crossings are making highways safer for people and wildlife

It’s a busy fall morning on stretch of Colorado highway, and rush-hour traffic is picking up. Along the fence line, more than 40 female and juvenile elk have bunched together, waiting for a break in the cars. Some drivers slow down. Some stop. Others speed past, not realizing how close they are to a collision that could total a vehicle, or injure or kill a passenger or one of the animals gathered just beyond the guardrail.

For generations, mule deer and elk have followed the same seasonal migration routes across Colorado, moving between high-elevation summer range and lower-elevation winter habitat each spring and fall. But as the state’s transportation network has expanded, many of those ancient migration pathways have become increasingly dangerous places to cross.

One such place is U.S. Highway 160 in southern Colorado. The highway cuts through expansive sagebrush shrublands and piñon-juniper woodlands that provide important habitat for resident and migratory wildlife. Along one section between Pagosa Springs and Durango, Colorado Parks and Wildlife found that nearly 60 percent of vehicle crashes involved wildlife.

Across the state, efforts are underway to reduce those conflicts. Colorado is emerging as a national leader in wildlife connectivity, investing in overpasses, underpasses and fencing systems that help animals move safely across the landscape while reducing risks for motorists. NFWF and its partners have helped advance that work through projects that reconnect migration routes long disrupted by roads and development.

A Costly Problem, Statewide

Roads help us move from place to place, but they can also cut off the routes animals rely on to reach food, water, seasonal range and breeding grounds, with consequences that ripple through entire herds.

Those consequences extend to Colorado communities, too. The state records nearly 4,000 wildlife-vehicle collisions every year, and some estimates put the real figure even higher. Deer are involved in more than 80 percent of those crashes, which together cost Coloradans roughly $80 million annually in property damage, medical treatment and other expenses.

The stakes go beyond dollars and fender benders. “When you hit an elk or deer, you’re taking away one of our most precious resources in Colorado,” Chuck Attardo, an environmental project manager with the Colorado Department of Transportation’s (CDOT), told Denver’s ABC 7. Hunting, angling and wildlife-related tourism contribute an estimated $5 billion a year to the state’s economy, Attardo notes. “So, there’s a significant economic investment in our wildlife as well.”

Two Projects, One Corridor

To address these challenges, NFWF has partnered with CDOT on multiple projects along U.S. Highway 160, a key transportation corridor that intersects some of Colorado’s most important big game habitat.

In the San Juan Basin, CDOT partnered with the Southern Ute Indian Tribe to improve habitat connectivity and reduce wildlife-vehicle collisions between Durango and Pagosa Springs — home to roughly 27,000 deer and 19,000 elk, the second- and third-largest herds of their kind in Colorado. NFWF funding helped extend fencing to existing overpass and underpass structures, guiding animals toward safe crossings instead of oncoming traffic.

“This is a heavily used corridor by vehicles and an important area in the San Juan Basin for big game,” said Scott Wait, senior aquatic biologist for Colorado Parks and Wildlife, in a project update. “Deer and elk spend the warm months in the high country to the north, but most big game move to the important winter range areas south of the highway during the winter. So there is a huge number of deer and elk that cross the highway at that location.”