Deer-vehicle collision prevention techniques and factors influencing a motorist’s ability to detect deer at nigh


Category:  Wildlife Science
Linked Publication
Language: English
Author(s): Lauren Linz Mastro
Description: Every year in the United States 1.5 million deer-vehicle collisions (DVCs) occur resulting in >29,000 human injuries, >200 human fatalities, 1.3 million deer fatalities, and 1 billion dollars worth of property damage. Despite the magnitude of this problem, there are relatively few well-designed studies that have evaluated techniques which can be used to reduce DVCs. Techniques to reduce DVCs fall into 4 categories: reducing the number of deer, reducing the number of vehicles, modifying deer behavior, or changing motorist behavior. Despite a limited amount of data, multiple studies have shown properly installed and maintained fences combined with wildlife crossings to be the most effective method of reducing DVCs. Methods with unproven effectiveness include: intercept feeding, repellents, reduced speed limits, caution signs, and the addition of roadway lighting. Stimuli designed to frighten deer (e.g., deer whistles, flagging and deer reflectors) have been shown to be ineffective because they cannot be perceived by deer or do not elicit a flight response. Well designed studies are needed so that we can acquire the knowledge on how to reduce frequency of DVCs. Most DVCs occur at night when deer are active and the ability of motorists to see them is impaired. The ability of motorists to detect deer at night and the factors that influence detection were examined using deer decoys, volunteer motorists, and a series of driving courses. Deer decoys were detected at significantly greater distances when located on the right rather than on the left side of the road and when <10 m from the road’s edge. Detection distances were significantly longer for high-beam headlights versus low-beam headlights and when there was no snow versus when there was snow on the ground. Moving decoys were detected at similar distances to stationary ones. Additionally, decoys were detected at greater distances in the absence of reflectors than in their presence. The use of high-beam headlights may increase detection distances and reduce the frequency of DVCs.