06/01/2018

In Wyoming, A Solution To Wildlife Traffic Accidents May Be In The Bag

4:10 minutes

deer standing in road with red and blue filter
This isn’t an uncommon sight in Wyoming. Credit: Shutterstock

state of science iconThis segment is part of The State of Science, a series featuring science stories from public radio stations across the United States. Maggie Mullen is a reporter for Wyoming Public Radio, and her story comes to us from the Mountain West News Bureau.


Mountain West states like Wyoming and Montana are high risk for wildlife-vehicle collisions. These accidents result in expensive damages and sometimes even death for both wildlife and drivers. One group of scientists found an unlikely solution.

Sinks Canyon Road in southwestern Wyoming is one of the state’s hotspots for wildlife-vehicle collisions. The canyon is a corridor to the Wind River Mountain Range for animals and the road winds up steep hills and tight corners.

There weren’t any deer or other big game on the drive to meet conservation scientist Corinna Riginos. But she said that may have been because of the time of day.

“Dusk and dawn, particularly dusk, I think is when the most collisions occur,” said Riginos. “Deer tend to be active at that time, and you also tend to have more cars on the road. So if you think about the dead middle of the night, you have a lot of deer activity, but not that many cars.”

You’ve probably driven by one before and not noticed it, but wildlife reflectors are poles on the side of the road.

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“Which are intended to flash when headlights hit them and warn deer that the car is coming and to make the deer stop and be more cautious about crossing the road,” said Riginos.

And there have been a lot of studies on reflectors, but Riginos said the results are mixed and not very impressive.

So the Wyoming Department of Transportation asked Riginos to lead a group of scientists and figure out whether or not the reflectors were actually keeping animals off the road.

So Riginos and her team developed an experiment. They’d cover up some reflectors, leave others uncovered, and then compare the results.

“We covered them with this cheap, easily available and durable material, which just happened to be white canvas bags,” Riginos said.

And to their surprise—the bags turned out to be more effective than the reflectors. Riginos said they used thermal video footage to look at how the deer were behaving.

“We could actually see that in the white bags situation, that the deer were more likely to stop and wait for cars to pass before crossing the road, instead of just running headlong into the road,” said Riginos.

They also looked at the total number of deer hit by cars under the two different conditions and the white bags prevailed. Riginos said the reflection of headlights on the bags might have simply startled the deer and alerted them to the cars.

Drivers in Wyoming have a one in 79 chance of hitting wildlife.

“It’s also possible that that looked to them like their rump patch,” said Riginos. “A lot of times raise their tail and show a white rump as a warning sign of a predator or other danger.”

Finding solutions like this are important. Drivers in Wyoming have a one in 79 chance of hitting wildlife.

Jon Oman with State Farm Insurance said hitting a deer with your car is one problem.

“But sometimes we end up seeing a bigger safety issue by folks being almost prideful about not hitting that deer, that elk or that moose, and then, of course, they go off the road, they roll their vehicle, or hit an icy patch or something,” said Oman.

Oman said not only are these accidents dangerous, they’re expensive, too.

“The average deer hit, the average elk hit, if you will, the average moose hit, State Farm is roughly paying out an average of $5,325 per claim,” said Oman.

According to the Wyoming Department of Transportation, there are about 6,000 big game vehicle collisions every year. Oman said that high number could be because of the large volume of wildlife, especially deer. Wyoming also has a higher speed limit than a lot of states. The same is true for Montana, where drivers have a one in 57 chance of hitting wildlife.

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Both states have incorporated what Corinna Riginos said is the best prevention tool.

“The gold-standard is underpasses or overpasses, or both, with plenty of fencing on either side so that the animals have to go and cross the road at those under and overpasses. And those are 80 to 90 percent effective consistently throughout the world,” said Riginos.

But crossing structures aren’t always possible, especially in places like Sinks Canyon where the topography isn’t very practical. They’re also very expensive.

Riginos said, “that’s when continuing to explore other options like the white bag effect are necessary.”

But Riginos also said that the solution probably isn’t to go put a bunch of white canvas bags along Wyoming’s highways.

“I would love to find some partners to take it forward and develop a true technology that does better than the white canvas bags and testing it thoroughly and come up with something lasting and effective,” said Riginos.

For now, Riginos has some advice for drivers—slow down where wildlife may be crossing, and keep your eyes on the road.

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Segment Guests

Maggie Mullen

Maggie Mullen is a reporter and host with Wyoming Public Radio in Laramie, Wyoming.

Segment Transcript

IRA FLATOW: And now, it’s time to check in on the state of science.

SPEAKER 1: This is Kiki– for WWNO, St. Louis Public Radio, Iowa Public Radio News.

IRA FLATOW: Local science stories of national significance. All right, you know the little riddle, the chicken one– why did the chicken cross the road? Well, today we’re going to ask, why did the deer cross the road? And if you live in the mountainous West, this question does not lead to a punchline.

Wyoming, Montana, Idaho are all states rich in four-legged megafauna, from deer to pronghorn, or elk, or moose. And in these states, the idea that you may someday hit one of these majestic animals– well, it can feel inevitable. And that’s why conservation scientists in Wyoming are trying to find cheap ways to keep deer off the highway and away from speeding cars.

And one group found an unexpectedly effective technology– cheap, white canvas bags. Here now with more is Wyoming Public Radio reporter Maggie Mullen. She recently reported on the story for the Mountain West News Bureau. Welcome to Science Friday.

MAGGIE MULLEN: Well, thanks for having me, Ira. It’s great to be here.

IRA FLATOW: Nice to have you. Cheap canvas bags.

MAGGIE MULLEN: That’s right. Yeah, so just to paint a little bit of a picture to begin with. So the white canvas bags were placed on the top of these wildlife reflectors, which are basically these series of tall poles with this red reflective material on the side of them that are intended to flash when headlights hit them. And that’s supposed to warn wildlife.

And this was part of an experiment by some Nature Conservancy scientists to find out, do these reflectors actually keep animals off the road? These reflectors are all over the world.

They’re not just in Wyoming and Montana. But the studies that have been done on them, the results are really quite mixed. So these scientists wanted a definitive answer, do these reflectors work?

IRA FLATOW: And? Did they get one?

MAGGIE MULLEN: No, the reflectors are not– they at least know that the reflectors aren’t as good as these white canvas bags. The experiment that they designed was they put these bags on some of the poles, and they left the others uncovered. And they covered these poles with just what happened to be these white canvas bags, because they’re cheap, they’re durable, they are easily available.

And to their great surprise, these white bags ended up working much better. They used thermal footage to look at the deer. And they could actually see them approaching the road, and then seeing these bags, and acting more cautious, and actually waiting for cars to pass before they crossed the road.

IRA FLATOW: And so what reason can they give for having this success with the white bags?

MAGGIE MULLEN: Well, it could be two different things. To the human eye, these bags are pretty easy– they’re pretty visible. They’re pretty easy to spot. But if you think about headlights striking a series of white bags, it could be that they just kind of startled the deer or alerted them to the cars.

It’s also possible that the bags looked, to the deer, like their rump patch. A lot of times, deer raise their tail and show a white rump as a warning sign to other deer, like, hey, there’s a predator around, or some other kind of danger, like a speeding vehicle.

IRA FLATOW: Wow. So we now know what you can do with your Public Radio tote bag, if it’s a white bag.

MAGGIE MULLEN: That’s right. We were thinking this might be the most Public Radio resolution there has ever been.

IRA FLATOW: So is this being adopted? I mean, seriously, people are using it now?

MAGGIE MULLEN: Well, that’s the thing. Not anytime soon in Wyoming. And I do know there are some folks in the UK that have gone out and actually put some white bags up on their roadside poles.

But there’s still some work to be done. More testing needs to be done to see the long term effects, because that’s the thing. The white bags could have just been this shiny new object that the deer were reacting to.

So I think these scientists are hoping that they can look at it over a longer period of time. And then they can kind of start to think about developing something more permanent that does even better than the bags.

IRA FLATOW: And everybody can try their own experiment with their Public Radio tote bags.

MAGGIE MULLEN: That’s right.

IRA FLATOW: Thank you, Maggie.

MAGGIE MULLEN: Yeah, thanks so much, Ira.

IRA FLATOW: Maggie Mullen, reporter for Wyoming Public Radio.

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About Christie Taylor

Christie Taylor is an associate producer for Science Friday. Her day involves diligent research, too many phone calls for an introvert, and asking scientists if they happen to have an audio recording of their research findings.

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