Jim Laybourn, Star-Tribune correspondent

A coyote searches for food after sitting out a recent snowstorm earlier in the day near Kelly in western Wyoming.

RAWLINS (AP) - The coyote - adaptive, secretive, resilient - continues to challenge wildlife management specialists in Wyoming who seek an effective response to "one of the most amazing animals on the face of the planet."

That's the opinion of biologist Rod Merrell, a USDA Wildlife Services employee who also has studied mountain lion, wolf and grizzly bear predation on livestock and wildlife in the state.

In 2004, coyotes took almost 20,000 of the 30,000 Wyoming sheep and lambs lost to predators and were responsible for 58 percent of total predation on calves and 25 percent of predation on cattle in Wyoming.

"Coyotes have saturated all of the landscape. It's not that it's a bad species, but when it causes problems, it needs to be managed," said Merrell, who has been a trapper all his life.

The best time to kill coyotes for population reduction in areas where there is historical damage to livestock or wildlife is mid-January through mid-June, when coyotes are breeding and establishing territories, according to Merrell. During this time, there is no major dispersion of movement.

"They'll be having pups soon, and the adults you can remove now will have a real impact on the coming year's production," said Rod Krischke, director of the USDA's Wildlife Services program.

"We take every coyote we can find" during that time, Merrell said. "You leave a void in the landscape, which, within this void, the antelope or the deer can have their fawns, and that's a critical time frame.

"It's a proven fact that if you do not remove 70 percent of the population in a given area, it won't begin to decline," Merrell said.

Two federal government trappers, Tracy Villwok and Wade Jones, are assigned to the eastern and western regions of Carbon County.

Currently, coyote management in the state is done more for agriculture than for wildlife, Merrell said.

"It's still by far and away the biggest predator problem people face," Krischke said.

According to Merrell, before 1985, predator control was an eradication program that included the use of broad-band poisons.

"We no longer target coyotes that are not causing a problem. We try to identify the specific coyotes that are preying on sheep or cattle. Those are the ones we go after. We try to stop the damage and then back off. That's our game plan."

"It's not a control program. That's not going to happen in real life in the field," said Hank Uhden, administrative officer for the Wyoming Animal Damage Management Board. "You manage populations. You want to write a plan and target the areas where the money will be used the most effectively - fawning grounds for antelope or deer, or lambing and calving grounds during certain times of the year - and use different methods."

Carbon County rancher Niels Hansen has been working with the Carbon County Predatory Animal Board, "timing when we put pressure on coyotes to take pressure off the calves during the calving season.

"Whoever the trapper is, we go out and show them where we're going to be calving, where we plan to have cattle in critical times, so they can go in when there's good snow cover," Hansen explained. "They can go out and do some aerial hunting in those areas and thin the population down."

"If you fly over and you kill seven coyotes and two of them are bred females, you just killed 12 more coyotes, because they're not going to have the pups," Merrell said.

Where pockets of intense sheep operations exist in Wyoming, such as in Lincoln, Sweetwater and Uinta counties, Wildlife Services trappers are required to do more, according to Merrell.

"There's something about sheep and coyotes. There are coyotes out there that will never kill calves. There are not coyotes that will never kill sheep. If you give a coyote an opportunity, they will attack sheep."

Coyotes are not protected by state or federal laws.

"They have such a track record of damage, and they're so common," Krischke said. "But they're very elusive and secretive, and you can put a lot of time in looking for them."

Like Merrell, Krischke doesn't believe bounties are an effective means of managing coyotes.

"When there are bounties, people are going to go to areas where coyotes are common and plentiful, and they're going to take those coyotes because they're easy to get, and not the areas where damage is occurring," Krischke said. "I feel like you need to be more targeted and more specific."

"Bounty systems don't work because they take the young of the year, the stupid ones," Merrell added. "The ones that are taking the wildlife are the old, experienced, wild coyotes."