The increase in deer-vehicle accidents has created a demand for preventive measures. A red reflector system (Swareflex wildlife reflectors) that reflects vehicle headlights to the side of the road has been claimed to frighten deer from the highways because red is instinctively frightening to the deer. Using penned deer, this research examined the premise that red is instinctively frightening to the white-tailed deer by measuring the effectiveness of red reflectors in keeping deer from crossing a line defined by the reflectors. No evidence was found that the deer avoid the area marked by the reflectors, or that they exhibit any other behavior that suggests that red is instinctively frightening to them. The results are considered in the light of other reports that vary in the degree to which they suggest that the reflectors are effective on the highway. It is argued that, where they are effective, the reflectors may have influenced the behavior of the drivers rather than the behavior of the deer.

Because of the steady increase in deer-vehicle accidents in recent years, it has become desirable to find a means to keep the white-tailed deer off of the highways when vehicles are present. In 1971 a red reflector system was introduced that reflects vehicle headlights to the side of the road to frighten the deer away from the roadway until the vehicle has passed. The basis for the reflector system is the assumption that