Used without specific written permission, but the magazine mailed us the copy by request.
Full credit is given to the original author.
A need to physically test deer whistles and explore the absence of ultrasonic sound arose from the absence of scientific literature coupled with the general unwillingness of companies that market deer whistles to provide any meaningful data supporting their claims. Working independently and using different methods, researchers in both Georgia and Wisconsin arrived at similar conclusions. The physical properties of ultrasonic sound negate its effectiveness at distances required to warn deer. We know little about the auditory limits of deer, but what we do know indicates that deer hear approximately the same frequencies as humans. If deer could hear ultrasound, we do not know that it would alarm them or induce a flight response.