Oh, rats.

The poet Robert Browning described them thus in the Pied Piper of Hamelin:

Every day at the store, it was the same thing — chew marks on a loaf of gluten-free bread, every day, for four months.

“The pest control officer thought for sure someone was pulling his leg. He could find no evidence of a rat, but every morning this gluten- free bread was gnawed on a little bit,” says Alberta rat and pest specialist Phil Merrill.

It was a rat, all right, and it was eventually apprehended in Olds, Alta. It shows that the wily rodents can outsmart even the experts, on occasion, but the battle to keep Alberta’s rat-free status is continuous and generally successful.

“By our definition, it’s probably more rat free than ever before,” says Merrill. “Our definition of rat free is we don’t have a breeding population of rats that we’re trying to control. We realize that every now and then we get an infestation and then we eradicate that infestation and then we’re rat free again.”

Merrill has managed Alberta’s program since 2010 and recently updated its history. Though rats were first reported in North America in 1775, they weren’t found in Saskatchewan until the 1920s and didn’t work their way into Alberta until 1950.

That’s the year they were found on a farm near Alsask, which is still a trouble spot as far as rat infestation is concerned, Merrill said.

The history of Alberta’s war on rats, found on the Alberta Agriculture website, recounts many battles through public outreach, mandatory control, toxicants, inspections and eradication efforts.

“Although there was some initial resistance, public interest and support for rat control was favourable, particularly from people who had rats,” reads the history, without any sign of irony.

And the personnel assigned to rat-control tasks were dedicated. One Alberta Agriculture official went above and beyond to convince people about the safety of warfarin, an anti-coagulant still used today for rat control.

“An Alberta Agriculture staff member ate warfarin-treated rolled oats while discussing rat control and the physiological effects of warfarin,” the history says.

“He was able to effectively demonstrate the relative safety of warfarin to concerned community members, and they were able to move forward together.”

Alberta is not alone in its battle or in its success, says Merrill. Saskatchewan has stepped up its program over the years and could potentially be rat-free within 10 years.

“We expect a few infestations right along the Saskatchewan border as they come from one farm to another, but Saskatchewan is doing a way better job than they have in the past. They have anywhere from two-thirds to three-quarters of their RMs declared rat free.”

Internationally, Ireland and New Zealand are both working toward rat eradication, and South Georgia Island in the southern Atlantic Ocean has achieved rat-free status.

“The world is getting more and more rat free all the time,” Merrill says.

“Our standard of living has increased. We handle our food much better. (Rats) evolved to live off our food, and as we treat our food better, they have less chance of getting at it.”

Farmers in particular have made improvements that stymie rats, he added. There are few remaining wooden granaries, which are favoured rat hangouts. There are fewer large outside chicken and hog operations.

Feedlots, silage pits and greenfeed bales are the main attractants now.

So are garbage dumps.

A rat infestation in Lloydminster about 20 years ago took seven years to manage. In Medicine Hat, a colony escaped eradication for two years, in 2012-14.

“We dislike dumps,” Merrill says.

“Rats like them and we dislike them for control. They’re hard to deal with. It’s hard to find the rats. Too much habitat.”

Alberta’s rat hot line at 310-RATS is key to keeping the province rat-free. Merrill says the line is now getting five to 10 calls a week about potential rat sightings, although most involve mistaken identity.

Muskrats and pocket gophers are the rodents most frequently mistaken for rats — muskrat in spring and gophers in fall.

What’s the key to noticing the difference?

“I look mostly for the hind feet,” says Merrill. “Muskrats have big hind feet. The rat’s hind feet are dainty, like a mouse’s.”

And if you don’t want to get that close? Merrill laughs at that.

“Even from across the room you can look at the feet,” he says. “A muskrat’s got big toenails as well. If you can see toenails in a picture, you know it’s a muskrat. A pocket gopher has big claws on his front feet as well. They have claws like a … miniature badger.”

Then there’s the tail.

“A rat can’t lift his tail. He drags his tail, and so when he’s running or moving, there’s a tail drag. A muskrat has control of his tail.”

Calls to the RATS line require some detective work, but identity of the varmint in question can often be confirmed over the phone, says Merrill.

For example, if the “rat” was seen during the day and for any length of time, it probably wasn’t a rat.

“If it wasn’t heading for cover and never seen again, then it’s not a rat. And if you say you saw it cross a road, well, you could not get a rat to cross the road. You could not.… He’s heading for the deepest grass. He’ll run under a tractor tire to get out of sight.”

However, Merrill says those in the rat control program welcome all calls. It’s better to report a potential sighting and be wrong than to ignore it and be right.

Should a report be confirmed as a rat sighting, local pest control officers are called upon to respond. Warfarin baiting is still the preferred prevention method, but an infestation calls for the use of bromadiolone, a more powerful anticoagulant.

The Alberta rat control program costs about $500,000 annually. The cost of having rats as permanent and steady residents, according to studies, would be about $43 million annually, says Merrill.

That figure would include property damage, replacement costs and the cost of consumed and contaminated food.

Rats also spread disease and, when in homes, can harbour and recirculate bacteria that affect human health.

Merrill said there were four infestations in Alberta last year, none the year before and two so far this year. His job continues.

“People keep sending us their darn rats.”

Rats in poetry

The poet Robert Browning described them thus in the Pied Piper of Hamelin:

They fought the dogs
and killed the cats
And bit the babies
in the cradles

And ate the cheeses
out of the vats
And licked the soup
from the cook’s own ladles

Split open the kegs
of salted sprats
Made nests inside
men’s Sunday hats
And even spoiled
the women’s chats

By drowning their speaking
With shrieking and squeaking
In fifty different sharps and flats.

Test your knowledge:

Think you know about rats? Take Alberta Agriculture’s quiz at here and see how you do!

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