The province has long-touted its decades-long efforts to keep rats out of Alberta, now, that status is at risk – after a number of rats were found near Medicine Hat.

Officials said 19 rats were discovered in the Medicine Hat regional landfill last week – since then, all have been destroyed, but more have been found.

“This is certainly the largest infestation we’ve ever had in the county,” County official Jason Storch said.

Since the initial discovery was made, a total of 60 rats were found in the area – but that number could climb.

The discovery was announced by Agriculture Minister Verlyn Olson Wednesday, at a press conference at the Medicine Hat landfill.

“What I know is that Albertans want Alberta to be rat free,” Olson said. “It’s definitely worth a trip down here for me to talk to the people who are working on this problem.”

Traps and infrared digital cameras have been set up around the landfill in an effort to catch any remaining pests.

Since it was implemented in the early 1950s, the ‘Rat Patrol’ has worked to eliminate rats within an 18,000 square kilometre control zone, stretching from the southeast corner of the province, along the province’s eastern boundary to the Cold Lake area.

These days, a total of ten inspectors are on patrol, the program costs $350,000 annually.

Much of the program’s success can be attributed to geography and population – except for the control zone, much of the province is protected by the sparsely populated prairie, mountains in the west, and dense forest in the northern portion of the province.

The patrol was established following an outbreak of Norway rats near Alsask, Alberta.

On the programs 50th anniversary in 2002 the province estimated the rat patrol had contributed to saving about $1 billion in potential property damage, livestock losses, human suffering and health care – as well as lost and contaminated food.

According to the province, one pair of rats can thrive, as long as they have shelter and access to food, and can produce as many as 15,000 offspring within one year.

As for this particular case, as long as the number of rats doesn’t increase to more than 1,000, the province can continue to call itself rat-free.

With files from Sonia Sunger