Going on a road trip? Study shows how to reduce roadkill

With summer roadtrip season approaching, two new Canadian studies have come out with scientific strategies to prevent roadkill. The answer? Fences, lots of fences.

Road trips are fun for the family but often fatal for wild animals. A new study shows fences can help

A new study shows that fences can help reduce road kill (StateFarm, Flickr)

Let's get right to it, how do we stop roadkill?

Fences. Lots and lots of fences. 

In a study conducted by McMaster University researchers, they found a shocking reduction in the frequency animals were found on the road when fences were built. Now, this particular study was solely looking at a wetland in Ontario, home to many different species of turtles and snakes, but their results were impressive. Chantel Markle, a PhD Candidate at McMaster was the lead author on this study

"So in sections where we had complete fencing — so this means there is full intact fencing on both sides of the road — we saw that the turtle mortality declined by almost 90 per cent, and for snakes we were able to cut the mortality rate in half," she said.

Those are impressive numbers and something that Markle thinks applies to all different kinds of terrestrial wildlife. Most species also benefit from having corridors, or artificial culverts or bridges, to make sure their habitat is not fragmented, but of utmost importance is making sure they survive long enough to cross the road using these other engineered methods.

How did the scientists estimate the scope of the problem?

For Markle's study, they used a combination of motion activated cameras around terrestrial culverts — these are little safe passages under roads that small mammals, reptiles and other species can use to cross the road — as well as actually tagging turtles to help ID them. 

That being said, there was some road walking to count road kill, too.

Why should we care that the numbers are so high?

Fair question, but you could also say there is a bit of environmental responsibility to it. National parks — which millions of people are expected to visit this year —  are often protected or fragile habitats. These places, like wetlands, parks and undisturbed ecosystems, are crucial to the health of the environment, so while it may just be one small turtle, turtle populations are declining in ever increasing numbers and their health is one piece of the puzzle to preserve wetlands. 

Jochen Jaeger from Concordia University of Montreal has thought a lot about the importance of reducing road kill and how this affects more than just a dent in your car. He believe it's about preserving the diverse species that co-inhabit our planet.

"Anything that reduces biodiversity is a great issue, so that includes biodiversity loss due to roads, Jaeger said. "So, we are all killing them, we're all contributing, but people just assume 'oh that's a small side effect,' but that's just wrong: it's not small, it's big. We have so many roads and so much traffic. It's a huge impact on biodiversity."

Who is going to pay for the fences?

Each unique ecosystem or area will also be unique in their funding strategies. Obviously fences work the best and are the most expensive option, but in the McMaster study they found there was a series of provincial and federal government grants that helped pay. An American granting agency was also interested in the study because the study area is around the Great Lakes and therefore this shared geography made them share their resources.

Some communities are also interested in spending their own hard-earned dollars because they see it as a safety measure — a fence keeping moose or deer off the road is a good thing — or they see it as their environmental responsibility.

Markle knows this first hand from her own field study on turtles and snakes.

"When it started back in 2006, it was really spearheaded by a group of local citizens who said 'We're tired of seeing these species being hit on the road, and we want to do something about it,' and this turned into a ten year study with really great results in the end, and I hope that it can act as an encouragement for other communities who are seeing something environmental in their area that they want to try to make a change. I mean if this project is any indication, you can make a difference."

If you can get money to protect rare species of turtles or even common snakes, it's possible to make it work in your own community if you are concerned about safety and/or wildlife.


Torah Kachur

Science Columnist

Torah Kachur has been the syndicated science columnist for CBC Radio One since 2013. Torah received her PhD in molecular genetics from the University of Alberta and studied how worm gonads develop. She now teaches at the University of Alberta as a contract lecturer in cell biology and genetics.