Sauntering along sidewalks and turning up dead in backyards, rats are an increasingly regular sight in the Danforth and Woodbine area, leading longtime residents to wonder what's brought so many of the rodents to their neighbourhood.

"I had one come up in my basement toilet. Luckily I had the lid closed," said Carolynn Smith, who in 20 years at her house on Gledhill Avenue had never seen a rat until one drowned in her toilet last summer.

Paul Nielsen, who came home to a drowned rat in his basement apartment toilet last summer, as well, had never seen one before either.

"I flushed it ten times to be sure it was well gone," he said in a message to CBC Toronto, explaining that he's trapped about four behind his workplace in the area since.

Tenants of a house in the area sent CBC Toronto this image of their recycling bin, chewed through by rats. They estimate they've seen rats about 20 times in their backyard since moving in last month. (Submitted by Lisa Grummitt)

Zach Mraovic, also a longtime resident, encountered his first rat when he trapped one that had nested in his car's engine bay, adding that he's since seen them on driveways and sidewalks.

"It seems like it's increasing very steadily and a lot of people are concerned," said Mraovic who, along with a number of other residents, traces the increase in rats to construction and sewer work in the area over the last few years.

"Ever since that construction took place they have had a crazy increase in that area," he said.

Construction, warm winters play a role

An extermination company and Coun. Janet Davis, whose ward includes the area, agree with the residents — construction could very well be part of the explanation for the uptick in rats.

Davis pointed to two instances of sewer construction in the area last summer as possible culprits.

Sewer work and other construction work that digs into the ground can send rats scurrying for new homes, explained Mike Heimbach of Abell Pest Control.

Paul Nielsen snapped this photo of a drowned rat in his toilet, which he discovered last summer. (Submitted by Paul Nielsen )

The same issue cropped up in the downtown core in 2014, when construction at Union Station displaced a large number of rats from longtime underground nests.

Also part of the equation though, said Heimbach, is the warmth of the last two winters in the GTA, which failed to kill off the typical amount of rodents.

"Last year and this year we've seen an about 26-per-cent increase in calls for rats from new customers, especially in Ontario. A lot of it is weather-driven," he said.

Sharp upswing in sales of rat traps, poison bait

Along with calling in exterminators, residents in the Danforth and Woodbine area have tried to tackle the problem themselves through snap traps and poison bait.

Alex Liakopoulos, the assistant store manager at a Home Depot close to the neighbourhood, said he first noticed sales of rodent traps and poison bait spiking in 2014.

Between 2013 and 2015, sales of traps rocketed up by nearly 60 per cent at his store and have continued to climb since, albeit at a more modest pace, he said.

Zach Mraovic used a snap trap in his engine bay to catch a rat that had been nesting there and chewing on wires. He spent $400 last summer on traps and bait stations. (Submitted by Zach Mraovic)

Mraovic, for one, has spent hundreds of dollars on products to deter rats from coming to his property, and he said his grandfather, who lives nearby, has successfully killed 25 rats in his backyard using snap traps.

Other people interviewed by CBC expressed concern about both kinds of rat deterrents, worried that curious pets could end up hurt or poisoned.

Calls to 311 'useless'

It was concern about what kind of trap to use that led Gina Mackenzie to call 311 after seeing a rat eating her birdseed two weeks ago, but she was re-directed to a wilderness centre where she was unable to leave a message.

"I really was trying to get advice from the city," she said, describing the call as "useless."

Mraovic said that he had encouraged neighbours to call 311 to give the city a sense of the problem, but heard similar stories to Mackenzie's from those who tried.

"I have had multiple people who said 'I called 311 and they laughed at me,' 'I called 311 and they told me there's no way of recording this,'" he said.

A city spokesperson told CBC Toronto that they do not track the number of rats in the city or keep any rat statistics.

Toronto's approach to rats is spread out over several departments, city spokesperson Tammy Robbinson said in an email.

City Parks staff watch for rises in rodents and hire exterminators as needed. Toronto Public Health investigates when a restaurant is involved. Exterminators are employed to keep the rat population in city facilities and squares under control.

Finally, Municipal Licensing and Standards is called in to investigate when property standards are an issue. For example, if a neighbour has a mound of garbage in the backyard.

Local councillor says she's requested bait program

At Davis's request, Toronto Water staff put poison bait in two sections of sewer in the area last week to prevent more rats from relocating.

Davis said she understands why her constituents have been confused about where to turn for help, having had a difficult time of her own figuring out who to talk to at the city.

Coun. Janet Davis told CBC Toronto she has contacted Toronto Water and asked that staff help the neighbourhood address the rat issue. (John Rieti/CBC)

"It doesn't fit neatly into one division," she said, adding that she'd like to see the complaints recorded.

Mraovic also wants to see a more organized pest-control effort from the city.

"There are a lot of homeowners that are out money in terms of actually paying a pest-control company. It's just not acceptable," he said. "You'll never get rid of the problem but you can help regulate it."