Projects Funded for Kimberley Rodrigues


Benefits and Costs Associated with Nonlethal Depredation Efforts for Sheep and Lamb Operations in California

Tina Saitone and Kimberley Rodrigues


Specific Objectives of the Project

Despite increased pressure to employ nonlethal depredation efforts, sheep and lamb operations have little to no information about the benefits or costs associated with implementing one or more of these practices. Conservation biologists and animal rights activists are increasingly concerned with livestock-predator conflicts and maintaining ecosystem diversity. Yet, this comes at a cost to producers whose economic viability is threatened either by losses due to predator or by employing cost-prohibitive nonlethal depredation efforts. This purpose of this project is to quantify both the potential economic benefits associated with nonlethal depredation efforts as well as the costs associated with implementing and maintaining these systems.

Summary of Results

Sheep and lambs in California are particularly susceptible to carnivorous predators, particularly coyotes. Since 1951, the UC ANR Hopland Research and Extension Center (HREC) has been the UC system’s principal sheep research facility, with a flock of more than 500 breeding ewes in 2015. Despite use of “conventional” nonlethal and lethal predator-reduction efforts, mitigating lamb and sheep losses at Hopland has historically been a difficult management challenge. This is also true for thousands of sheep operations throughout the United States. In an attempt to limit deaths due to predators, HREC has adopted an innovative suite of nonlethal predator-prevention strategies including upgraded fencing, mob grazing, frequent pasture rotation, and guardian dogs.

While heuristically these results appear to be very favorable, to date no one has quantified and analyzed the costs associated with the use of these nonlethal predator-prevention efforts. HREC staff have documented their prevention strategies, kept an accounting of the implementation and maintenance costs, and maintained records of sheep and lamb populations and death losses. At present, we have collected and compiled these data and are in the process of using the time variation created by the sequential implementation of the various prevention strategies employed by HREC to identify the incremental benefit associated with each depredation strategy.

In the very near term, we will quantify both the benefits and the costs associated with the use of guardian dogs as a nonlethal predator prevention strategy at HREC. This information will allow ranchers to make informed decisions to improve the economic performance of their operations.