CHICAGO (CBS) — It’s estimated there are 30,000 coyotes are living in Illinois. The number in Cook County could be 2,000 or more.

With the coyote population exploding, CBS 2’s Bill Kurtis takes us an up-close look at a coyote den.

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At four weeks old, the pups living in the Crabtree Cook County Forest Preserve couldn’t have been cuter. Six of them were staying in a den in the woods, but concerns about coyotes are growing among nearby residents.

Last month, a coyote attacked an Aurora woman’s dog in their yard.

“When I opened the patio, I saw my dog Diamond in the coyote’s mouth,” Sharon Poindexter said at the time.

Usually, coyotes raise concerns about the safety of pets, but three weeks ago, a man was bitten by a coyote while in his back yard in Aurora.

Aurora police spokesman Dan Ferrelli said, “This was the first report of a coyote biting a human being in the city of Aurora, that we know of.”

It’s been more than 20 years since the last reported biting incident in the Chicago area, but sightings of coyotes are up.

“We’ve had about 100 calls for coyote sightings so far in 2012. At this time last year, we had less than 10,” Ferrelli said.

Aurora is not unique. Famous incidents in Chicago include a coyote caught running down State Street. And, a few years ago, another wandered into a downtown Quizno’s sandwich shop.

Coyotes even have dens in the city, including one near in Lincoln Park.

Coyotes have no predators, except for humans, according to Stan Gehrt, a researcher with the Cook County Coyote Project.

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His team microchips the pups for tracking, and weighs them. Plenty of food in the wild is a good sign.

“If the food supply is low, that might contribute to conflicts between coyotes and people, because then they may be more likely to go into people’s yards,” Gehrt said.

Over the last 10 years, the project has radio-collared more than 300 adult coyotes to study their movements.

Gehrt said most coyotes, even those living close to humans, do not become a problem.

“One of my favorite coyotes spent her whole life living in downtown Schaumburg, without a single incident. She never attacked anyone’s dogs,” he said.

However, he noted “these are wild animals, even though they are awful cute.”

Gehrt said peoples shouldn’t try to make friends with coyotes, and must never feed them.

“The ultimate conflict – where a coyote actually bites a person – that was usually preceded by people feeding them,” Gehrt said. “It works out best for them, and for us, if they are afraid of us.”

To avoid feeding coyotes, never leave pet food outside, be sure to keep your barbeque grills clean, and secure your trash.

In Aurora, for the first time ever, the city was forced to trap and remove the two coyotes that attacked a local man last month. It’s rare, but when a coyote becomes a serious nuisance or danger, that’s what has to be done.



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The Cook County Coyote Project is funded by the Cook County Forest Preserve and Cook County Animal Control