A comparison of bobcat and coyote predation on lambs in north-coastal California

We investigated predation on lambs by bobcats (Lynx rufus) relative to coyotes (Canis latrans) from June 1994 through November 1995 at Hopland Research and Extension Center (HREC) in north-coastal California, where both predators occur at equally high densities. Lamb losses during this study were typical for HREC and surrounding ranches and included 64 (5.3% of lambs pastured) confirmed predator kills and 134 (11.1%) missing individuals. Fifty-seven of the predator-killed lambs were attributed to coyotes, whereas none were assigned to bobcats. The proportion of bobcat scats containing sheep remains was small (4.2%), and occurrence did not peak in the lambing season, suggesting that sheep consumed by bobcats were scavenged. Sheep were common in coyote scats (21.4%) and occurred most frequently in scats from the winter-spring lambing season. Coyotes were responsible for all lamb kills in intensively monitored pastures for which predator species could be identified. Use of space by radiocollared bobcats was not noticeably influenced by the presence of lambs. We concluded that bobcats were not important predators of lambs at HREC and not the cause for the relatively large numbers of lambs missing and unaccounted for each year.