Controlling wily coyotes? Still no easy answers

In Gehrt's Chicago study — the largest of its kind on an urban coyote population in the United States — researchers found that some harassment devices worked, including two instances where wolf urine was successful keeping coyotes out of a yard. Wolves were at one time natural enemies of the coyotes.

The researchers at other times used a more low-tech method: groups of volunteers chasing coyotes while shaking coffee cans full of coins.

Researchers know less about city coyotes than rural ones, primarily because they're relatively new on the scene. Few cities had any coyotes to speak of in the late 1980s. Now, they're in most metropolitan areas across the country, Gehrt said.

About 300 have been radio-collared and tracked in Chicago. For the most part, they stay out of trouble — apparently feeding more often on rodents, deer and rabbits than family pets. Those that do pose problems may need tailor-made solutions.

"Some of the things, like sirens, might work out on the range but not as well in the city, for obvious reasons," Gehrt said.

Unpredictable
At the Utah research center — which focuses primarily on conflicts between livestock and predators — 165 acres are ringed with high fences and outfitted with a high-tech security system.

Inside, about 100 coyotes are kept busy testing the latest nonlethal devices and techniques. Those that pass muster in this outdoor laboratory are taken into the field — often to ranches where coyotes have been a problem.

One of the items is a suitcase-shaped device with a flashing light and noise system that blurts out sounds of bowling alleys, car crashes and people yelling. Some bolder coyotes simply ignored the device, others stayed away and a third group were frightened at first but eventually overcame their fears.

"Coyotes just aren't that predictable," Shivik said. "That's what makes this so hard."

Other experiments have focused on "conditioned flavor avoidance" — something akin to smelling tequila the morning after a bender — and electrified strips of red flagging that provides a brief jolt for unsuspecting animals.

Researchers in homemade perches overlooking large enclosures spend days, weeks or longer watching coyotes, looking for any helpful hints about how their minds work and how they translate knowledge into behavior.

Ultimately, the solution to keeping coyotes out of trouble will be a complicated one, Shivik said. Sometimes it will require a mix of lethal and nonlethal methods that change over time. Landowners and wildlife managers will have to be flexible but, in the end, coyotes and people should be able to get along.

"We're trying to help coyotes as much as we help people," Shivik said.

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