Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Electrical Engineering


In cooperation with the United States Department of Agriculture, Agricultural Research Service, the Electrical Engineering Department at South Dakota State University is testing the effects of ultrasound on coyotes. It is known that coyotes can hear high pitched tones of higher frequency than that of the human ear. The overall goal of this research is to investigate the feasibility of using ultrasound to repel predators, mainly the coyote, from livestock. It has also been found from preliminary experiments that there is a significant increase in the heart rate of the coyote during exposure to noise levels of 100 to 110 dB. The purpose of this thesis is to develop instrumentation for this research. In order for the reader to understand the purpose of instrumentation which will be discussed in the following chapters, the experiments which are to be conducted will be described in the following paragraphs. The experiment is divided into two phases. The object of phase one is to find the sound which is most annoying to the coyote. Coyotes are exposed to various sounds seen as frequency modulated sound and interrupted sound, with the frequency between 16 and 40 KHz. Whether the coyote is annoyed or not is determined by observing the heart rate and the coyotes physical reactions by means of a video tape recorder. An EKG (electrocardiogram) transmitter is mounted on the chest of the coyote. From the results of phase one, the most annoying sound will be determined. Phase two is based on an avoidance technique used in psychological experiments. A 4 by 12 foot pen is divided by a hurdle into two compartments. Ultrasonic transducers are mounted in both compartments. The most annoying sound is then switched on and off in either side randomly and alternatively. The important observation will be whether the coyote is avoiding the sound or not; i.e. if the sound is presented in one compartment, we expect the coyote to move to the other.

Library of Congress Subject Headings

Predatory animals



South Dakota State University Theses



Number of Pages



South Dakota State University