The efficacy of an ultrasonic cat deterrent

Ultrasound deterrents for a variety of mammals, including cats, are widely available in the commercial market, but few have been independently tested for efficacy. This study tested the efficacy of an ultrasonic cat deterrent 'Catwatch (c)', using 63 and 96 volunteer observers in two long-running (18 and 33 weeks) blind experiments. Results indicated that the device did have a moderate deterrent effect, reducing the probability of a cat intrusion into a garden by approximately 32% in the first experiment, but not in the second. The average duration of intrusions was reduced by approximately 38 and 22% in the two experiments, respectively. The magnitude of the deterrent effect appeared to increase with time, since the device was deployed. It is likely that the size of the deterrent effect could be increased by positioning the device(s) more carefully with regard to entry points to the garden that are regularly used by cats. (c) 2005 Elsevier B.V. All rights reserved.