Development and evaluation of devices designed to minimize deer-vehicle collisions
D'Angelo, Gino Jude
MetadataShow full item record
Deer-vehicle collisions are an increasingly common occurrence throughout the range of white-tailed deer (Odocoileus virginianus), resulting in human injury and death, damage to vehicles, and waste of deer as a wildlife resource. Most states attempt to minimize deer-vehicle collisions through a variety of techniques. However, few research efforts have sufficiently examined the efficacy of such techniques, and a distinct paucity of information exists on deer behavior relative to these mitigation efforts. A more thorough understanding of the physiological processes driving deer behavior may aid in the development and implementation of strategies designed to minimize the incidence of deer-vehicle collisions. In this study, I evaluated the behavioral responses of white-tailed deer relative to a common commercial device for prevention of deer-vehicle collisions, wildlife warning reflectors. I also examined the anatomy and physiology of the hearing and visual systems of deer that may prove integral to the invention of economically effective strategies to minimize deer-vehicle collisions. I observed deer behaviors relative to roads before and after individual installations of 4 colors of wildlife warning reflectors (red, white, blue-green, and amber) during 90 observation nights. My data indicated that wildlife warning reflectors did not alter deer behavior such that deer-vehicle collisions might be prevented. Using auditory brainstem response testing, I determined that white-tailed deer hear within the range of frequencies we tested, from 0.25-30 kHz, with best sensitivity between 4-8 kHz. The upper limit of human hearing lies at about 20 kHz, whereas we demonstrated that deer detected frequencies to at least 30 kHz. This difference suggests that research on the use of ultrasonic (frequencies >20 kHz) auditory deterrents is justified as a possible means of reducing deer-human conflicts. To gain knowledge of visual specializations influencing the behavior of white-tailed deer, we examined gross eye characteristics, structural organization of the retina, and the density and distribution of cone photoreceptors. White-tailed deer possess a horizontal slit pupil, reflective tapetum lucidum, cone photoreceptors concentrated in a horizontal visual streak, and typical retinal structure. The visual system of white-tailed deer is similar to other ungulates and is specialized for sensitivity in low light conditions and detection of predators.