Predation on Range Sheep with No Predator Control

Abstract

A Great Basin band of open range herded sheep was monitored intensively for losses between June 8 and September 29, 1976, in an area where organized predator control had not been employed for the preceding 9 years. Verified losses due to all causes totalled 69 (4.4% of the band), of which 59 (86%) were due to predation. Forty-eight of the predator losses were lambs, a 6.3% loss of the lambs in the herd. Eleven adults were killed by predators. Ninety percent of the predator losses were attributed to coyotes (Canis latrans), 2% to bobcats (Lynx rufus), and 8% to predators of undetermined species. Physical condition was determined for 41 of the sheep attacked by predators: 93% were healthy and 7% were in poor condition. Predation intensity varied from approximately one loss every 6 days in June to almost one per day in August and September.