The population of Torbay, N.L., has surged in recent years, and humans aren't the only ones moving in.

An influx of rats in the town just north of St. John's has left some residents stumped about how to wipe out the pests, which have taken to rooting around in residential garbage boxes, nesting under sheds and even chewing up backyard hot tubs.

"There's more sightings. The rats are huge. They're not little field mice like you would expect from having pasture land in Torbay," said Amanda Harris, who has lived in the town for nearly 20 years.

"These are just pure sewer rats. They're big."

Their size, number and persistence mean the rats are wreaking havoc on properties in Torbay, which has a population of about 8,000. Harris saw that destruction up close last week, when she spotted a critter digging around her hot tub.

Only then did she notice ominous signs of an infestation.

Amanda Harris points out the remains of her $16,000 hot tub. She's warning others about the damage the rodents can do. (Malone Mullin/CBC)

A hole for the hot tub's power cord led to an extensive network of tunnels chewed into the tub's foam insulation, rendering the $16,000 machine useless, she said.

"They chewed the wires for the lights … all the insulation, they just ripped it out," she said, pointing to the tub's skeleton, now little more than a wooden frame riddled with droppings and teeth marks.

In the front of her home, Harris pointed to trails leading from drainage pipes running along her property to garbage bins made from wooden slats, a common sight in Torbay and notorious among her neighbours for attracting pests.

A well-worn rat track was clearly visible in the snow outside Harris's home, despite the box remaining empty until garbage day, when Harris hauls out trash she's keeping secured indoors.

That precaution, also taken by some neighbouring houses, has proved futile, she said, standing in the pit her hot tub once occupied. "It just seems to be getting worse instead of better."

Town asking for official complaints

Mayor Craig Scott said his own property has so far evaded the rodent invasion, although the issue was brought up in council meetings several times in the past year.

Scott said the town sent out a "rat card" with information on how to manage rodents when the issue was first raised.

Town staff haven't reported any further complaints since then, Scott added, but he's aware residents are taking to social media to document their battles with the rodents.

Scott implored people to call the town as well, explaining he can't take action without an official record of sightings to justify it.

Harris found these two specimens — about the size of a four-month-old kitten — inside her tub. (Ted Dillon/CBC)

"I tell people if you have an issue like that, you need to make sure you contact the town so that we're aware of it and we can keep track of these complaints," he said.

"If the matter gets so bad and we need to do something, even as much as putting out that rat card … until we are made aware of the issue through proper channels, it's hard for us to try to address that."

The problem isn't unique to Torbay: St. John's has also grappled with the creatures in recent years. In 2017, pest control company Orkin Canada rated St. John's the rattiest city in Atlantic Canada.

But why?

Harris, along with other Torbay residents, told CBC News the problem got worse after a bypass was constructed about eight years ago.

Persistent development may be a factor in the apparent population increase. Several other pest control companies contacted by CBC agreed that development in any area disturbs underground tunnels where Norway rats make their homes, sending them scurrying for new shelter — somewhere warm and close to water and food.

Rod Squires, an exterminator, disagrees. He, too, has seen an increase in rats in Torbay and surrounding towns, but has a different opinion on what's causing the growth.

"Construction doesn't have anything to do with a rat population," he said. Rather, it's food sources, like bird feeders and accessible garbage bins, that draw rodents to an area regardless of nearby development.

"It's mostly negligence on people's part, mostly homeowners."

Rod Squires, who owns a pest control company in the Torbay area, says the best way to prevent property damage is to not leave food sources out for destructive critters. (Ted Dillon/CBC)

While Harris still suspects roadwork is the culprit, much of Torbay's boom happened a decade ago, leaving her puzzled as to why rats are moving in now, and even more bewildered at what she can do to stop them.

With a small dog around, she's not keen on putting out poison and hasn't figured out a game plan besides keeping her garbage indoors — and hopes the town can work together to at least diminish the rats' healthy population.

For now, Harris is warning others to keep a close eye on their outdoor investments before they meet a similar fate to her beloved hot tub.

"It was our winter haven," she said. "Unfortunately now it's ruined."

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