Field Notes
U.S. Fish & Wildlife Service
Field Notes Entry   
SACRAMENTO FWO: Helping Wildlife Avoid the Rivers of Predators
California-Nevada Offices , August 2, 2012
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Road Ecology is the study of the effects roads have on nature and the science has come a long way.
Road Ecology is the study of the effects roads have on nature and the science has come a long way. - Photo Credit: John Cleckler/USFWS
The animals in areas around roads see a multitude of effects due to the roads around them and each has a strong impact.
The animals in areas around roads see a multitude of effects due to the roads around them and each has a strong impact. - Photo Credit: John Cleckler/USFWS

By Ashley Cotter, Summer Intern, Sacramento FWO

Almost everyone has been in a car at some point. And while you were in that car, what did you see on the road? There’s the constant flow of cars, the lanes, the signs, and the roadkill. A raccoon or a squirrel, maybe you didn’t see it, but could smell a deceased skunk somewhere close. Now imagine that one dead animal on the side of the road, add up the total number of days you drive during a year and multiply that by the number of people who drive in the world. That is a lot of roadkill.

Road Ecology is the study of the effects that roads have on nature, and one aspect is roadkill. John Cleckler, from the U.S. Fish and Wildlife Service’s Sacramento Office, was kind enough to give me an overview so I could give you, the average public citizen,  a little knowledge about this new science.

Roads have various effects on the animal community that surrounds them. They are a constant threat that can cause behavioral disturbances in animals, behavioral barriers, erosion, change of landscape, and chemical run off from the cars.

Behavioral Disturbances and Barriers: When an animal such as a salamander is travelling to a pond its instinct is to go directly to the pond, it doesn’t comprehend the idea that there could be a highway in between it and its destination. Salamanders don’t have a GPS that can guide them away from harm, so they walk right into the street. The salamander, raccoon, or deer experiences a disturbance in their natural behavior when they enter that road/freeway, and unaware of what to do, they walk right into traffic. These "barriers" in their natural habitat are harmful to not only the animals but to drivers as well, who swerve or hit them and in turn are harmed.

Changing Landscape: Most of our roads have been here for a while, so we don’t always think about their consequences. But there are a few new roads here and there that are added to our system of transportation. These new roads have an impact on not only the animals themselves but on their habitat as a whole. When a new road is put in, it causes a change in landscape. The road could potentially cut a forest in half or divide a population of species in two. These changes could cause a decrease in animal population or cause a species to evolve at a different rate than its other members.

Chemical Run Off: The chemicals our cars leave on the road are dangerous to the habitats of all animals. These chemicals are washed off the road from rain or spills and they get washed into the rivers and the soil of the surrounding area. The chemicals have been known to affect amphibian breeding and cause forced evolution in salamander populations. These chemicals also have affected the distance that plants can grow from a road, and have caused native plants to be outcompeted by nonnative plants that adapt better to exhaust from the cars.

While discussing wildlife tunnels/crossings, John Cleckler said, “Roads are like rivers of predators to all species of wildlife.” To us, a road is a tool of transportation, a means of getting from point A to point B, however, that tool may split up point A and point B for creatures. Each year the road kill adds up, and it isn’t always just a little chipmunk on the side of a freeway. There are animals anywhere from endangered butterflies to elephants that have suffered from car collision around the world.

Animals cannot cross a road safely without some sort of wildlife crossing. Wildlife crossing can be located above or below the road in areas that are known for condensed animal crossings. There are a few of these animal crossings in California. In Southern California there are drainage culverts known to be used by wildlife, and there have been multiple crossings made for animals throughout the state, such as under the road tunnels for California tiger salamanders. John Cleckler says with the growing science of road ecology and all of the wildlife tunnel/crossing projects throughout the world “[California] can’t help but be pulled along a little bit.”

However, California is behind the curve when it comes to wildlife crossing/tunnels installation. While there is talk of animal overpasses being built in both Northern and Southern California, most of the animals of California in need of these crossings are smaller animals like amphibians, and for these animals the crossings are harder to sell to the public.

Getting interest and support for a big fuzzy bear or a fragile deer in need of a crossing is generally easier than building up interest for a salamander or a toad. The crossings/tunnels cost a lot of money and even though the crossings for smaller animals cost less, their cause is harder to raise money for.

What You Can Do to Help

A sure way to stop roadkill is to stop driving but that will never happen. Our society depends on mobility and transportation. However, there are a few things the public can do to help reduce the effects of roads on nature.

1. Learn – Educate yourself about the wildlife in your area, whether or not there are any crossings or tunnels near you, and what current and future road projects could benefit from a wildlife crossing. A good place to start is Road Apple on Facebook.

2. Report – The California Roadkill Observation System is the first statewide roadkill reporting website. It allows the public throughout California to record their observations of deceased animals and the context of their environment and through CROS helps increase the knowledge of potential wildlife car collisions. Visit http://roadecology.ucdavis.edu/ to participate.

3. Support – When you hear of a wildlife crossing project in your area, support it.


Contact Info: Sarah Swenty, 916-414-6600, sarah_swenty@fws.gov
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