Study Details Cattle Losses From Wolves

OMAHA (DTN) -- A new study from the University of California-Davis (UC Davis) shows how much cattle producers in the state are seeing in losses from an expanding and protected gray wolf population. The losses from the predators is in the millions of dollars, according to an UC Davis press release (https://www.ucdavis.edu/…).

Long believed to be extinct in California, a gray wolf was seen entering the state at the Oregon state line in 2011 and a pack was spotted in Siskiyou County in 2025. By the end of 2024, seven wolf packs were documented in four other locations.

As more wolves appeared, ranchers in those areas feared they would prey on cattle. Tina Saitone, a UC Davis professor and Cooperative Extension specialist in livestock and rangeland economics, sought to study the direct and indirect effects of the wolves.

"There's not really any research in the state on the economic consequences of an apex predator interacting with livestock," she said.

Saitone proposed the research to her husband, Ken Tate, also a UC Davis professor and Cooperative Extension specialist in rangeland sciences. Ben Sacks, director of Mammalian Ecology and Conservation Unit in the UC Davis Veterinary Genetics Laboratory, also joined the project to analyze wolf scat (waste).

The research focused on three wolf packs and their interaction with cattle in northeastern California from June to October of 2022, 2023 and 2024. Funding came from the U.S. Department of Agriculture's Western Sustainable Agriculture Research and Extension Program and the Russell L. Rustici Rangeland and Cattle Research Endowment.

The UC Davis study found that one wolf can cause between $69,000 and $162,000 in direct and indirect losses from lower pregnancy rates in cows and decreased weight gains in calves. Total indirect losses were estimated to range from $1.4 million to $3.4 million depending on moderate to severe impacts from wolves across the three packs.

In the study, researchers also discovered that 72% of wolf scat samples tested during the 2022 and 2023 summer season contained cattle DNA. Hair cortisol levels were elevated in cattle that ranged in areas with wolves, indicating an increase in stress in cattle.

"It is clear the scale of conflict between wolves and cattle is substantial, expanding and costly to ranchers in terms of animal welfare, animal performance and ranch profitability," Saitone said. "This is not surprising given that cattle appear to be a major component of wolf diet, and the calories drive their conservation success."

Researchers trekked into remote rangelands to mount motion-activated game cameras, obtained access agreement from ranchers and permission to put GPS collars on cattle. Neither Saitone or Tate had undertaken that kind of work, but years of collaborating on other research paid off, with land managers and ranchers providing information and support.

"This is such a sensitive issue for ranchers and landowners that it took pretty much every bit of my 30 years of network building to get us access to land and cattle for this study," Tate said.

Gray wolves are protected under the state and federal law as endangered species. The California Department of Fish and Wildlife (CDFW) depredation compensation program paid out $3.1 million in initial funding. The agency said on April 2 that it was moving into a new phase of wolf management given increasing population numbers.

The next phase entails evaluating the status of gray wolves and evaluating potential permits to allow "less-than-lethal harassment." This includes noise or use of motorized equipment to deter the predators, an online tool to provide location details of wolves with GPS collars and investigating livestock losses due to depredation and other actions.

Saitone and Tate said the research could better inform the conversation.

"We do need to get toward some kind of coexistence," Tate said. "We don't know what that's going to look like, but it doesn't look like what we're doing now, that's for sure. It's not sustainable. This research helps, I think, to advance that conversation."

Russ Quinn can be reached at Russ.Quinn@dtn.com

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