Rat alert in Calgary's Coventry Hills

Bylaw officers are overseeing the cleanup of an alley in the northeast neighbourhood of Coventry Hills following the discovery of a rat infestation.

City officials won't name the neighbourhood where two rats, first spotted on Thursday, were caught. But CBC News has learned that some households in the neighbourhood of Coventry Hills have received letters about a rat problem, asking them to clean their basements, yards and garages.

Greg Currie, a longtime resident of the neighbourhood who didn't get a letter, was surprised to find contractors in an alley near his home, hauling away garbage, old furniture and building materials. He plans to buy traps and rat poison, as well as talk to his neighbours about the problem.

"I would be worried about them coming over to my house with my children," he said. "I guess with rats they set in and start breeding and then you can't control them in the area."

Alberta rat free?

Alberta has aggressively fought the pest since the 1950s and boasts of being rat-free.

"We would be naive to think the rats can't get here, because they can and they will," said Bill Bruce, director of animal and bylaw services. "Calgarians are fairly vigilant and when they think they see them, they call us."

The city gets about 125 rat calls a year, but not all are actually for rats, he said.

"We actually get about 15 to 20 rats a year that we remove from Calgary that come in on shipments. We actually had three this summer alone that have come in on people's holiday trailers or boats from Saskatchewan," he said.

Bruce wouldn't say which neighbourhood the rats were caught in. "I don't think there is value in stigmatizing a community," he said.

Bylaw officers have also brought in poison and traps and scouted the area to make sure there are no food sources or shelter for rats, he said. Signs of nesting in the neighbourhood have bylaw officers concerned, because a rat can produce 12 litters a year.

"The program is kicking in and in very short order there won't be any rats in Calgary again," Bruce said.

Rat patrol on alert

Calgary pest control expert Don Poulin said it is unrealistic to say Alberta is entirely rat-free, but he commends the City of Calgary's quick response to the latest sighting.

"You're 99.9 per cent rat-free, and as long as the government stays with what they've been doing, they can stay that way, but you have to take it seriously," he said.

Poulin suspects a pet rat escaped or was dumped in the neighbourhood and quickly became wild.  But he said people shouldn't be concerned about the isolated incident.

One of the rats caught in Coventry Hills has been confirmed as a Norway rat. Norway rats carry diseases and can damage crops and property, according to the Alberta government.

The province bans the purchase of rats as pets and has Alberta landowners along a swath of land 631 kilometres long and 25 kilometres wide patrolling for Saskatchewan rats.

Alberta's "rat patrol" has been have been watching that zone extra closely for rats following an infestation in the Saskatchewan city of Swift Current, where there are reports of people being bitten in their sleep.