Effectiveness of wildlife warning reflectors in reducing deer-vehicle collisions: A behavioral study

Various reflector systems have been in use for a number of years to reduce deer-vehicle collisions, but their effectiveness on a long-term basis is still in question. We examined habituation of deer to repeatedly occurring light reflections from WEGU reflectors by studying the behavioral responses of fallow deer (Dama dama). Our experimental design eliminated factors normally associated with light reflections from reflectors (vehicle noise, light), and deer were exposed to light reflections at predetermined time intervals. The distribution of the behaviors flight, alarm, movement of head, and no reaction varied among nights. Despite this variability however, fallow deer exhibited increasing indifference to reflections, which was explained by a habituation to the stimulus. Our results are expected to be valid fur other species of deer and other types of reflectors. Habituation of deer and technical limitations of the reflectors, such as limited angle and low light intensity of the reflection, mean that reflectors are not reliable as a method to reduce the number of deer-vehicle accidents on a long-term basis.