How We Can Make Driving Safer for Humans and Wildlife

This podcast is available in a video format. Find that here:

Cars have gotten safer in the last 50 years. Auto manufacturers and government regulators have spent a lot of time working on making it safer to drive. 

But the best way to be safe in a car is to not crash in the first place.

In Colorado, there are thousands of vehicle collisions with wildlife every year. Roads fragment habitat and migration patterns, forcing wildlife to try to get across busy highways — often resulting in tragic outcomes for people and wildlife. Even mild collisions are very expensive for the state and nearby communities. The average cost of hitting a mule deer is over $23,000.

Fortunately, there is a commonsense solution that protects both drivers and animals: wildlife crossings.

In 2026, WRA helped pass bipartisan legislation that will reduce the number of collisions in Colorado by building more crossings.

The benefits of preventing wildlife-vehicle collisions go far beyond safety. Wildlife crossings also connect critical habitat and safeguard ecological resilience, helping the West's unique species thrive even in a changing climate. With more funding, Colorado and states in the West can do even more to protect our communities and wildlife populations.

We talked to an expert to learn all about it.

Welcome back to our series about conservation funding in the West. In these episodes, we're exploring how the West can protect our wildlife, support our ecosystems, and make outdoor recreation accessible to everyone.

2 Degrees Out West is a podcast from Western Resource Advocates, an environmental conservation organization that's focused on the Interior West. WRA works across seven states to protect our climate, land, air, and water. WRA protects and advocates for Arizona, Colorado, Utah, New Mexico, Nevada, Montana, and Wyoming.
 
2 Degrees out West is a podcast for advocates and decision makers who want to fight climate change and its impacts across the West.

On 2 Degrees Out West we talk with climate experts and advocates to bring you stories, experiences, and insights from their work in the places we call home.

It is Hosted by Dave Papineau 

Want to be part of 2 Degrees Out West?

• Email us with thoughts, suggestions, and interviewees at dave.papineau@westernresources.org.
• Follow us @westernresourceadvocates on Instagram.
• Create a clip sharing "our Bright Climate Future for the West" and send it to us at dave.papineau@westernresources.org. to be included in one of our next episodes.
• Join our email list to stay updated on when new episodes are released and calls to action on how you can help the West.
•  ...

Transcript

How We Can Make Driving Safer for Humans and Wildlife AUDIO

Dave Papineau (Host): [00:00:00] Hey, come here. I want to show you something 

It's right over here. Come here 

Dave Papineau (Host): It's this right here. And you might look at this and think this is an unassuming section of fence by an unassuming section of road, but there's a secret that is keeping you safer any time that you drive on this road on your way to Buena Vista.

Cars themselves have actually gotten a lot safer in general in the last 50 years. We're way better at building things that crash well and protect you in the event of a car crash. But the best way to be safe in a car crash is just to never get into one in the first place, and that's what this fence does.

In Colorado every year, there are thousands of collisions with vehicles and wildlife. They often have tragic outcomes, not just for wildlife, but for people, too. The good news is we just passed legislation in Colorado that's gonna help build more of these, and the benefits of these wildlife crossings and fences go way beyond just protecting wildlife, but into [00:01:00] ecological resilience.

And we're gonna talk all about that, and to find out about it, I talked to one of WRA's experts who's been working on this problem for years in Colorado. And I found out that with more funding, Colorado could be doing even more to protect wildlife. Let's talk about how. Welcome back to our series on conservation funding in the West.

We're exploring different ways that we can fund protecting wildlife, ecosystems, and the communities of the West. On today's episode, we're talking about wildlife crossings.

Jon Holst: My name's Jon Holst. I am a senior policy advisor in the Western Lands program for Western Resource Advocates. 

Dave Papineau (Host): Jon says that Coloradans need to be paying more attention to the ways that wildlife and vehicles interact. 

Jon Holst: It's hard to [00:02:00] overstate how significant it is. According to roadkill data from CDOT the Department of Transportation, over 7,700 animals, mostly mule deer, were killed by vehicles across the state in 2025 alone.

In addition, I've seen hard numbers from the insurance industry indicating that the number of claims filed for wildlife vehicle collisions is really closer to 9,000 per year. So a lot of animals are getting hit on the highway. Unfortunately, between 2010 and 2025, these collisions resulted in 52 human fatalities and over 5,500 injuries.

Not only are these accidents really horrible and tragic from a human standpoint, but they also have real impacts on Colorado's economy. There's a study by Montana State University that estimates the annual cost of wildlife vehicle collisions in Colorado at $321 million the highest of any state across the West.[00:03:00] 

TV Host: Yeah, l- looks, looks like it's just a ding. There's no reason to get the insurance companies involved. 

I should still take down your information, though. Really? 'Cause- 

Dave Papineau (Host): y- Not only is hitting animals really dangerous for you, but it's also really expensive for you, and I'm willing to bet it costs more than you think it does.

Jon Holst: Most of our collisions are mule deer, and the average cost of hitting a mule deer believe it or not, exceeds $23,000. So it's quite expensive in terms of vehicle repairs and injuries. 

Dave Papineau (Host): There's a risk to life if you hit an animal, there's a risk financially if you hit an animal, and there's also an environmental impact from hitting animals.

It is not good to just be having deer get hit by cars all the time. 

Jon Holst: In addition to the direct mortality cost from collisions, roads fragment habitat and impair wildlife movement. Wildlife, especially migratory ungulates like deer, elk, and pronghorn that we have in Colorado, need to move relatively freely across the landscape to access the resources that they need to [00:04:00] survive all year long.

Colorado in particular, we have a lot of elevational migrations for big game. They basically s- summer in the high country and winter down in the mountain valleys. Studies have shown that most wildlife increasingly avoid roads as traffic volumes increase to the point that at really high traffic volume, roads can become an impenetrable barrier to wildlife movement.

In his book Crossings, Ben Goldfarb appropriately uses the term, quote, "moving fence" to describe the fence-like barrier to wildlife movements caused by constant streams of traffic on high volume roads. 

TV Host: Come on, while we have the chance. Gasping in the fumes, we gambled our lives trying to get through the traffic.

Dave Papineau (Host): That moving fence is one of the larger stressors that we have on wildlife as humans. Wildlife are resilient, and they can actually endure a lot. But Jon says when there's other stressors, like drought, for example, that vehicle [00:05:00] collisions can be the thing that pushes a population into decline. 

Jon Holst: Ultimately, this habitat fragmentation can decrease the carrying capacity of the landscape to support really large, robust wildlife populations, and also inhibits wildlife's ability to move across the landscape to adapt to things like climate change there is, it got to the point in, in some western Colorado populations where Colorado Parks and Wildlife years ago surveyed all of their biologists as well as the public and tried to identify those things limiting mule deer populations, and roadkill was actually identified as one of the main things that Parks and Wildlife needed to address declining mule deer populations.

Dave Papineau (Host): Wildlife managers think of a concept called compensatory mortality when they're thinking about how bad a certain thing is for a wildlife population. Jon explains what that is. 

Jon Holst: Compensatory mortality is essentially a way to s- to suggest that there's a certain number of mule deer that are frankly gonna die each year, based [00:06:00] on there not being enough food to eat, starvation, predation, other types of things.

So if one type of mortality doesn't get a percentage of the population, this is, I'm really oversimplifying, but if one type of mortality doesn't get a percentage of the population, another type of mortality is go- is going to get them. So more or less, there's a certain number of mule deer that aren't gonna make it through the year.

Dave Papineau (Host): So by itself, vehicle collisions aren't going to dramatically decrease or increase mule deer populations, but there's a catch. 

Jon Holst: Additive mortality means that it's a specific source of mortality that's actually gonna increase the overall number of mule deer that are gonna die. So you're no longer have this overall mortality rate for the population, but you're actually adding to that because the population is stressed for some reason and you're more or less gonna increase the number of deer that die within a particular geographic region that year.

Dave Papineau (Host): I gotcha. So what you're saying is there's like a, to put it in financial terms, there's like a black level where it's fine, like [00:07:00] we're still in the black and then we can push ourselves into the red when we have these other stressors that cause more vehicle collisions and decrease the population.

Jon Holst: Yeah. And it could be disease, it could be a number of other things. But if you have vehicle collisions on top of, poor habitat conditions, disease and other things, then you could definitely be going into the red.

Dave Papineau (Host): The good news is there's a way around this, where we can build our roads in a way that don't cause vehicle collisions, allow us to preserve migration corridors, and protect the resilience of our wildlife. And that's through wildlife crossings, like this tunnel that I'm in right now. 

Jon Holst: So wildlife crossings, are structures built either over or underneath the road to separate wildlife movements from vehicle traffic to provide safe passage for both wildlife and people.

So it's really [00:08:00] designed to really segregate the traffic from wildlife movement. 

Dave Papineau (Host): Above me is Highway 285, a road that I drive all the time to get in and out of the Arkansas Valley, and this crossing is helping to protect me and you if you drive on this road. Now, there's a couple of ways to build wildlife crossings.

You can build them like this, a tunnel that goes under the road, or you can build an overpass that goes over the road. But there's one kind of question that I had, and that's, how do I get a deer to use a tunnel or a bridge? 

Jon Holst: Be effective, they really need to be combined with wildlife fencing to help channel wildlife to the crossing structures.

And if constructed correctly, that system of crossing structures and wildlife fencing, connects habitat on both sides of the highway, so it's great for wildlife. But it also reduces wildlife vehicle collisions by 90% or more based on monitoring of structures that we've done across Colorado thus far.

Dave Papineau (Host): Now, when combined with fencing, these wildlife crossings are [00:09:00] very effective, and that 90% figure comes from a section of road near Kremmling, where I drive to and from all the time on my way to fishing spots. And we can also be incredibly precise with where we build these crossings. 

Jon Holst: We have these migrations that's basically, for these deer that winter down in New Mexico, and they migrate through four or five jurisdictions, private lands, tribal lands, state of New Mexico lands, state of Colorado lands, on up to federal land, BLM lands and Forest Service lands, to summer in the high San Juans. 

Dave Papineau (Host): Jon told me about this specific project with the Southern Ute Indian Tribe near Chimney Rock in Durango, Colorado, and he showed me how they were able to use very specific data to know exactly where to put this crossing.

Jon Holst: And when we first, or when the tribe first did this, big kudos to the tri- the Southern Ute Indian Tribe and Aaron Jonson, we didn't know how useful that migration information would be, but coincidentally, this work with the Transportation Alliance [00:10:00] trying to use the best available science to site where its crossing structures should go based on the number of wildlife vehicle collisions and where animals are actually migrating.

So we took CDOT's data to show roadkill information on Highway 160, and then we plotted it with the tribe's migration data, showing the highest density migration movement areas. And the intersection with the number of vehicle collisions, like the highest vehicle collisions, like, bam. It was like X marks the spot of this is where you need to put a wildlife crossing structure, and that's exactly where CDOT put the, the wildlife overpass and underpass on Highway 160 there by Chimney Rock.

And I can send you those maps, but they're fascinating to look at because you're just like- Yes ... "Holy cow, this totally makes sense." 

Dave Papineau (Host): Wildlife crossings reduced collisions on this section of road by 60%. Now, I'm not talking just about animal-vehicle collisions. I'm talking about all accidents, meaning there were 60% fewer accidents on this stretch of [00:11:00] road outside Durango.

That is an incredible number. Jon actually hunts some of the animals that go through that same corridor, and he said that these migration routes are not replaceable. They're somewhat of a family heirloom for the deer that travel on them. 

Jon Holst: And they literally migrate, like the same family groups migrate across the same location every year.

And then their offspring migrate across that same location every year. So the- these have been handed down, these migration routes, from generation to generation. And so it's crazy to think about, like, how long some of these migrations have been going on and how important they are for animals to actually access what they need.

Because if you sever that migration, even for one generation, right? Whatever happens, traffic volumes get too high, you build... somebody builds a fence, and so there's a generation that can't migrate, that's lost forever. And the impacts to the population then no longer being able to access those resources on the other side of the road that's gonna trickle down to, [00:12:00] population dynamics and what's gonna happen with that population.

But it's crazy to think about, and it really gives you a lot of incentive to we need to conserve. These pinch points are the most important areas where these animals are moving across the highway 

Dave Papineau (Host): And again, not only does this project preserve a critical migration corridor for local wildlife, it reduces vehicle collisions by 60%.

And wildlife crossings all across the west have similar rates of effectiveness. So the question is, if we're making roads that much safer, why aren't these things everywhere? 

Jon Holst: So they're really expensive. A recent survey of over 500 transportation agency officials identified funding as the number one barrier to investing in more wildlife crossing structures.

To give you a couple examples, a small underpass costs around a million dollars, while larger structures like the big one recently constructed, the Greenland Overpass on I-25, which spans six lanes of traffic- 

TV Host: The largest wildlife [00:13:00] overpass in North America is now complete. In Douglas County, CDOT says construction is done in Greenland near Larkspur and open for wildlife.

The overpass spans six lanes of interstate traffic, connecting 39,000 acres of habitat on both sides of I-25. 

Jon Holst: That costs around $30 million. So the upfront cost is really a substantial barrier. 

Dave Papineau (Host): We've already discussed how they protect vehicles, wildlife, and ecosystems, but they can also preserve economic value over time.

Jon Holst: Despite that upfront cost, some recent studies show significant cost savings over the lifespan of co- of crossing structures. Remember, like bridges, these structures last a really long time, like up to 75 years, and over that time period, there could be savings of hundreds of thousands of dollars each year in reduced accident rates.

One study in Washington State showed a savings of over $400,000 a year at some crossing structures. Another study in Utah showed a net savings of 15 million over the lifespan of a crossing structure. [00:14:00] So we'll see similar savings to that here in Colorado as we construct more of these structures. 

TV Host: We're following a bill just introduced that looks at reducing wildlife vehicle collisions across the state.

Now, the bill aims to build more wildlife crossings and safety infrastructure, and also reduce these kinds of collisions by 90%. 

Dave Papineau (Host): In 2026, WRA, alongside partners like Pew Charitable Trusts and several legislative champions, was able to pass Senate Bill 26-141, which was a funding measure for wildlife crossings in Colorado.

And this bill was a great start on making some of these crossing stories that we're talking about more prevalent throughout our state. The new legislation has a lot of runway to help build more of these wildlife crossings. 

Jon Holst: So the new bill is awesome, frankly. It's expec- expected to raise between four and eight million dollars a year.

And while that doesn't sound like a tremendous amount when you're talking about a structure that might cost 30 million a couple of things to keep in mind, is- This is [00:15:00] the first dedicated annual funding stream for building wildlife crossing structures and supporting infrastructure in Colorado.

And, it's actually believe it or not, the largest dedicated state funding mechanism for wildlife crossings in the entire country. So it's a, even though it's just 48 million doesn't sound like a tremendous amount of money it's a big deal. And even better, over the past five years, Colorado has been really successful at leveraging every state dollar invested to unlock about four federal dollars for crossing infrastructure.

So that means that 48 million from the new law of state money could unlock, 16 to 32 million of additional investment in Colorado. A significant amount of money going toward wildlife crossing infrastructure. 

Dave Papineau (Host): That's the good news. We're making progress on funding this infrastructure and getting it built where it's most needed.

But every story has a catch, and there's not all good news. So what's the bad news? And that's [00:16:00] simply the cost. You've heard us say it before, we still need more money. 

Jon Holst: It gets a, it's a good start. Building the crossings and the fencing along the highway will definitely reduce wildlife vehicle collisions, but it's not enough really to conserve wildlife movements and landscape-scale seasonal migrations for animals like mule deer, elk and other wildlife over the long term.

One of the great things about the new law is that it recognizes that in order for wildlife crossings to stay functional over the long term, there needs to be a concerted effort to work with landowners and local governments to ensure that high-density development doesn't encroach on either side of the crossing structures to the point that it restricts wildlife's ability to use them.

In addition to the crossing structures, the new law specifically provides funding for wildlife movement corridor conservation to address that issue. And we've begun at WRA working with Colorado Parks and Wildlife, [00:17:00] CDOT, other state agencies, and local governments to develop a strategy for how to smartly invest in landscape-scale corridor conservation.

So the new law is really, if you think about it, it's just seed money for this effort. We estimate that Colorado still needs over 100 million in annual recurring funding to safeguard open lands, wild places, and wildlife migrations from urban sprawl and all the other types of development we're seeing in Colorado.

So it's a great, we have a great start, but there's still a long way to go.

Dave Papineau (Host): Give wildlife managers the resources they need and what they can do to protect people, wildlife, and ecosystems is incredible, and that's really the story of wildlife crossings. The primary barrier to protecting wildlife usually isn't public interest or available science, it's funding to actually get these measures on the ground where they're needed, and that's what we're [00:18:00] trying to fix at WRA through measures like SB141, but also through more concerted efforts to build up conservation finance within Colorado.

These projects are expensive, and while important, they often get ignored without a stable and dedicated source of funding to make sure that they happen. When we're talking about needing sustained forces of conservation funding, this is what we're talking about, a pot of money specifically put aside for funding win-win projects like this that protect people, wildlife, and everything that we love about Colorado.

And wildlife crossings is really just the perfect example of that. It makes you safer, it makes wildlife safer, and it's a great investment for the money that we have to put into it. Stay tuned for the next episode where we talk about more ways that we can use conservation finance to help protect Colorado.

Lastly, we'd like to thank the sponsors who support our work. Our premier sponsor is Kind Design. Our signature sponsors [00:19:00] are Sweep, Denver Water, Scarpa, Solup, and Torch Clean Energy. Our supporting sponsors are Group Fourcan Engineering, Megafauna River Company, and BSW Wealth Partners