Research shows there’s very little that really works in keeping deer from causing car crashes. Steve Gent of the Iowa Department of Transportation says deer whistles on your car don’t really work, and “deer reflectors” along the roadside aren’t effective, either. The devices are placed along the roadway and reflect vehicle headlights into the fields, creating a sort of optical fence. In a three-year study, the DOT found 14 percent more dead deer along the stretches of road “guarded” by the optical fence, while the number of reported car crashes decreased. Gent says while that’s conflicting data, the deer reflectors obviously aren’t hugely effective. Gent says the one thing that has proven effective is an eight-foot-tall fence along highways, but it’s very expensive to install and to maintain since the deer dig out under it. Gent says the deer eventually find a way around any barrier that’s erected. Gent says it’s just like putting a radio in a patch of sweet corn to keep the raccoons out, and after a few nights the raccoons figure out things out and start eating the corn again. One of the least effective ways of reducing deer/vehicle crashes has been posting “deer warning” signs along the roadways, and legislators may ask the DOT to take the signs down. Gent says a good percentage of vehicle crashes in Iowa involve deer. Insurance industry experts say Iowans were paid at least $70 million last year to cover the damage from road crashes involving deer. Iowa’s part of a five-state research project on car/deer crashes, and research data’s posted on the Internet at www.deercrash.com.

Radio Iowa