University of California

The Coyote Lure Operative Device revisited: A fresh look at an old idea


Are R. Berentsen
Robert M. Timm
Robert H. Schmidt

Authors Affiliations

A.R. Berentsen is Research Associate, Department of Forest, Range and Wildlife Sciences, Utah State University, Logan; R.M. Timm is Superintendent and Cooperative Extension Specialist, UC Hopland Research and Extension Center; R.H. Schmidt is Associate Professor, Department of Environment and Society, Utah State University, Logan. Funding was provided by the California Department of Food and Agriculture Vertebrate Pest Control Research Advisory Committee, contract 03–0325. The authors thank John Hays, Jr., Jennifer Smith and Gary Johnson for assistance in the field, and two anonymous reviewers for providing helpful comments and suggestions.

Publication Information

Hilgardia 61(1):20-23. DOI:10.3733/ca.v061n01p20. January 2007.

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We field-tested the Coyote Lure Operative Device (CLOD), a bait delivery system for coyotes originally conceived by UC Davis researchers in the 1980s. Our objectives were to determine whether free-ranging coyotes would activate CLODs repeatedly when exposed to them over a 12-month period, and whether CLOD activations varied by season. We placed CLODs in pastures with a history of chronic sheep depredation at the UC Hopland Research and Extension Center in Mendocino County. Free-ranging coyotes activated the CLODs repeatedly, but more CLODs were activated during the winter months than at other times of the year. Our study suggests that the CLOD has the potential to become an important tool for managing coyote predation on livestock when used to deliver contraceptive or predacide baits.


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Berentsen A, Timm R, Schmidt R. 2007. The Coyote Lure Operative Device revisited: A fresh look at an old idea. Hilgardia 61(1):20-23. DOI:10.3733/ca.v061n01p20
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