Bands of domestic sheep lambing on the open range in south central Wyoming were monitored for predator losses before and following coyote (Canis latrans) removals. Experimental treatments, including (1) no removal (control), (2) removal of 2 adults and their pups, and (3) removal of pups only, were replicated 15 times each. Predation incidents (events) declined 98.2% and the number of sheep killed was reduced by 98.8% when adults and pups were removed. Removing only litters of pups resulted in a decrease of 87.7% in predation incidents and total kills decreased 91.6%. Overall, 23 of 30 predation sequences terminated immediately, whereas in all instances predation ceased within 3 days after removing adult coyotes, their pups, or both. In terms of "offending individuals," denning can be a selective means of coyote depredation control. Removing only litters of offending adults can be nearly as effective in stopping losses as removing the adults. Litter size did not appear to influence kill frequencies. A cost-effectiveness analysis is presented.
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