LITTLETON – For deer, the fall time change Sunday morning means trouble: a 16% spike in collisions with vehicles over the following week, despite years of safety campaigns and the construction of 75 special crossings along highways.
Drivers in Colorado collided with at least 54,189 wild animals over the past 15 years, according to newly compiled Colorado Department of Transportation records. That’s far fewer than in many other states, such as Michigan, where vehicle-life collisions often number more than 50,000 in one year.
The carnage — especially this time of year — increasingly occurs where animals face the most people along the heavily populated Front Range, beyond the mountainous western half of the state that holds much of the remaining prime habitat, state records show.
State leaders and wildlife advocates gathered on Thursday near one of the crossings along the high-speed C-470 beltway in southwest metro Denver to launch a safety campaign.
“We’ve made wildlife crossings a priority in our rural areas, and also increasingly in urban areas,” CDOT Director Shoshana Lew said. “We cannot put underpasses and overpasses everywhere. Particularly at this time of year, we urge everyone to be careful of wildlife.”
Lew credited the crossings with containing collision numbers that could be much higher in Colorado, given the traffic and the prevalence of deer and other wild animals. Most of the state’s highway construction projects, such as the work on Interstate 25 north of Colorado Springs that includes a large wildlife bridge, will factor in wildlife safety needs, Lew said.
The risk of collisions spikes this time of year due to deer and elk migrating to lower elevations, bringing more animals across highways. The end of daylight saving time also plays a role as more drivers navigate roads during the relatively low-visibility hours before and after sunset, when deer often move about.
In Colorado, the 54,189 vehicle-animal collisions that CDOT recorded from 2010 through 2024 caused the deaths of 48 vehicle occupants and more than 5,000 injuries. The animals breakdown: 82% deer, 11% elk, 2% bears.
Ten counties where vehicles hit the most animals during that period included five along the Front Range — Douglas, Jefferson, El Paso, Larimer, and Pueblo — with a combined total of 12,791 collisions, state records show. That compares with 11,068 in the other five counties in western Colorado — La Plata, Montezuma, Garfield, Moffat, and Chaffee.
Colorado lawmakers over the past two decades have directed funds for the installation of more and more wildlife crossings, typically overpasses and underpasses combined with fencing along highways. “These can be up to 90% effective in reducing collisions,” Environment America researcher Rachel Jaeger said.
Most recently, in 2022, lawmakers set up a wildlife safe passage fund with a $5.5 million investment for crossing construction. That money’s been spent. State transportation planners have identified locations where crossings are needed, such as the stretch of U.S. 40 between the intersection with I-70 and the town of Empire, where bighorn sheep live.
Wildlife-vehicle collisions have proved persistent enough that safety advocates have launched a social media campaign and are mulling new strategies, such as promoting ridership on CDOT’s intercity Bustang buses as an animal-friendly way to move.
“Leave your driving to a professional,” said Danny Katz, director of the Colorado Public Interest Research Group. “Just take public transportation.”
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