Step aside coyotes. Farmers and conservation officers in the West are dealing with a new threat that's wreaking havoc and multiplying fast.

During the past few years, hundreds of wild boars have escaped from pens where they were being raised on ranches in western Canada.

At first, experts believed the animals would be unable to survive the harsh winters. But they've proven to be wily survivors, grunting their way across land in the middle of the night.

Wild boar shot near Meleb, Man.

According to the latest estimates, there are now about 200 boars at large in Alberta, at least 50 in Saskatchewan, and more than 250 in Manitoba.

"It's aggressive by nature, it's prolific in terms of reproduction, and through its rooting and feeding habits, it's very destructive to farmland and native habitat," says Rob Bruce, of the Problem Wildlife branch of Manitoba Conservation.

Farmers worry that the animals, not native to Canada, may spread disease to domestic swine. The boars, which have large tusks, can also damage crops and rare Prairie plants.

Dave Gillies, a cattle rancher near Meleb, Man., recently shot a wild boar rummaging around inside a calf shelter.

"It was pretty much pandemonium here for the better part of half an hour," he recalled, as cows nearly trampled their offspring while trying to get away from the intruder.

Wild boars have become such a problem that Manitoba has passed a law permitting licensed gun owners to shoot and kill any of the creatures roaming at large. But the animals, which mainly travel at night, are not easy targets.

Experts predict that the hunters will have their hands full. They estimate that three per cent of the province's 3,000 captive wild boars get away annually – adding up to 90 new escapees on the run on the Prairies every year.