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Adaptive Strategy for Non-lethal Predation Management

Although the majority of sheep ranchers use nonlethal methods to protect their flocks from predators, disagreement still exits regarding the effectiveness and feasibility of many of these tools for large scale grazing operations. To gain a better understanding of how nonlethal methods may be used with large scale grazing operations on public lands, the Idaho Wood River Wolf Project was formed. The collaborative effort was first conceived in 2008 by a USDA wolf specialist and the Defenders of Wildlife.

The 7-year project collected data on sheep depredations by wolves in a demonstration area where a variety of nonlethal methods were used and compared it to data from an adjacent area where a variety of nonlethal methods were used and compared it to data from an adjacent area where sheep were grazed without nonlethal protections. Both areas were occupied by wolves.

Between 10,000 and 22,000 sheep grazed across nearly 1,000 square miles of the protected demonstration area. Field specialists strategically applied nonlethal predator deterrents and animal husbandry practices by adjusting for things such as habitat conditions, locations of known wolf packs, and the frequency or type of nonlethal methods used. Nonlethal methods included increasing human presence and the number of livestock protection dogs; fladry and turbo-fladry; spotlighting; scare devices, such as air-horns, blank handguns, flashing lights and radioactivated guard boxes; and monitoring the movements of radio-collared wolves. Results showed sheep losses to wolves were 3.5 times higher in the unprotected area than in the protected area. While packs of wolves were killed in the unprotected and adjacent areas, no wolves were killed in the protected area over the course of the project.

“The presence of one or more field specialists assisting in monitoring and deterring wolves played a critical role in minimizing wolf-sheep interactions because they were able to select appropriate deterrents based on site-specific conditions at the time,” notes NWRC research wildlife biologist Stewart Breck. “For instance, by monitoring the location of wolf packs and dens, field specialists were able to pen sheep bands and increase spotlighting at night when high-risk wolf encounters were likely.”

Although encouraging, Breck notes the adaptive approach to implementing nonlethal methods may not be easily repeatable, feasible or cost-effective for some ranchers. Familiarizing livestock producers and sheepherders with novel management techniques and gaining their participation in protecting sheep from wolves is critical for successfully reducing sheep depredations.

While encouraging, additional studies evaluating the time and costs associated with using such methods are needed. This is the first peer-reviewed study using multiple nonlethal deterrents to protect livestock across a large landscape. The findings provide valuable information to ranchers who may be interested in an adaptive predation damage management approach.

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Story Map:  Learn how the U.S. Department of Agriculture’s Wildlife Services program uses and recommends an integrated approach to resolve wildlife damage problems.

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