Proceedings of the Vertebrate Pest Conference

The effectiveness of frightening devices for reducing coyote predation on domestic sheep has not been adequately studied. Portable, battery-operated strobe light/siren devices protected pastured sheep from coyotes for a mean of 53 nights (10 trials) and 91 nights (5 trials). Results of ongoing tests of the devices for reducing predation on herded sheep on summer range in western Colorado have so far been encouraging. Future research needs are outlined.