ELECTRONIC FRIGHTENING DEVICES FOR REDUCING COYOTE PREDATION ON DOMESTIC SHEEP: EFFICACY UNDER RANGE CONDITIONS AND OPERATIONAL USE

Authors

Samuel B. Linhart, Denver Wildlife Research Center, Animal & Plant Health Inspection Service, Department of Agriculture, Denver, Colorado
Gary J. Dasch, Denver Wildlife Research Center, Animal & Plant Health Inspection Service, Department of Agriculture, Denver, Colorado
Richard B. Johnson, Denver Wildlife Research Center, Animal & Plant Health Inspection Service, Department of Agriculture, Denver, Colorado
Jerry D. Roberts, Denver Wildlife Research Center, Animal & Plant Health Inspection Service, Department of Agriculture, Denver, Colorado
C. Joe Packham, U.S. Department of Agriculture, Animal Damage Control, Animal and Plant Health Inspection Service

Date of this Version

March 1992

Document Type

Article

Abstract

A portable 12-v battery-operated coyote frightening device was developed for reducing coyote predation on sheep and evaluated on fenced pasture farm flock operations (1979-1982). In 1986, the final experimental model consisted of a PVC case, a timer, a blinking strobe light, and a warbling type siren that was activated for 7-10 seconds at about 6-7 minute intervals throughout the night. The devices were generally suspended about 2 m above the ground and were activated at dusk by a photocell and turned off about 2 hours after dawn by a timer. Here we report tests on high mountain summer sheep ranges (1982-1987), evaluation of the devices by ADC and external cooperators (1987-1990), and efforts to make the devices commercially available.

On high mountain summer range, the devices reduced sheep losses on average about 60% with a mean dollar value savings of lambs of over $2,400 per sheep band. In the operational evaluations, 84% of our cooperators indicated that coyote predation on lambs was lowered when devices were used. Manufacture and sale of the device under the name "Electronic Guard" was begun in 1991 by the ADC Program’s Pocatello Supply Depot.