I evaluated the efficacy of sound as a deterrent for reducing deer-vehicle collisions by observing the behavioral response of captive and free-ranging white-tailed deer (Odocoileus virginianus) to a range of sound frequencies within their hearing range. Captive deer exhibited no behavioral response when exposed to any of 5 different pure-tone sound treatments. I then evaluated the effects of a moving automobile fitted with a sound-producing device and speakers on roadway behavior of free-ranging deer. My results indicated that deer within 10 m of roadways did not alter their behavior in response to any of the 5 pure-tone sound treatments tested in a manner that would prevent deer-vehicle collisions. Many commercially available wildlife-warning whistles (deer whistles) are purported to emit similar consistent, continuous pure-tone sounds; however, my data suggest that deer-whistles are likely not effective in altering deer behavior along roadways to help prevent deer-vehicle collisions.
