The numbers that WCS's Berger found make her skeptical about the significance of predator control in the economics of sheep farming. But she doesn't dismiss predators completely as a threat to the industry.
"There are absolutely circumstances in which removing an animal that is causing predation losses will save some sheep," she said. "So this is really a question of what we hope to achieve by investing public resources to control predators.
"If the goal is to kill carnivores, then we've clearly been very successful. But if the goal is to actually help sheep ranchers earn a living and stay in business," she continued, "then I think we're targeting the wrong problem.
"You've had a [predator control] program in place for over 60 years, and you've lost 85 percent of the sheep producers," Berger said.
Again, Orwick disagrees.
"Clearly, the program does work in helping minimize losses, and it does it without significantly impacting the predator population," the ASI director said.
"That coyotes are the primary predator is not a 'perception' issue. Coyotes cause the majority of predator losses to sheep operations."
Orwick maintains that eliminating predator management "would take the predator losses of today37 percentand move it up so that 80 or 90 percent of all losses would be due to predators.
"I don't understand what the reasoning would be to take predator management out of the picture."
If predator control isn't having a great impact, as WCS's Berger says, could it be because not enough coyotes are being killed?
"It would be fair for sheep farmers to say that the program doesn't work because we're simply not killing enough coyotes," Berger said. "But that doesn't explain why you see the same trends in sheep production in areas where you have coyotes and areas where you don't. They're virtually identical."
Times have changed, according to Berger.
"It's important to keep in mind that, at the time that the predator-control program was conceived, public feeling in the country about large carnivores was quite different," she said.
"We were interested in civilizing the landscape and making it beautiful for humans only. That's changed. A lot of people are looking for a place where they can get away from civilization and experience nature and wildlife," Berger said.
"Maybe it's time to revisit our policy of controlling predators and also revisit what it is we're doing to help livestock producers, since what we're currently doing doesn't seem to be working."
ASI's Orwick sees predator control from a different perspective.
"I don't know of one magic solution to eliminate conflict between wildlife management and agriculture," he said.
"I argue that farmers and ranchers subsidize the public and the public's wildlife by providing private land and property for coyotes to make their living. Therefore, the public has a responsibility to assist in limiting or managing the severity of the damage and loss of private property."
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