'Squirrel invasion': Destructive rodents ready to invade your home this winter

It starts with a mysterious scraping inside the wall. A clatter in the attic. The strange rattle of tiny feet. 

These are the sounds of a squirrel infestation. 

With temperatures dropping in Alberta, the rodents will try to take refuge in homes — returning to stockpiles of nuts and seeds they've foraged over the summer.

Chewing their way through vents, pipes, shingles, and siding, they seek shelter in attics, making nests they will use as  havens for litters of babies in the spring. 

"It's usually one of two things, they're nesting up there ... or they're just storing food for winter," said Joe Woodcock, owner of Northern Pest Control Edmonton. 

"As soon as they don't want to be heard, they can be quite quiet so you can go years and years without hearing them —or ignoring them — and then you can end up with a big problem."

'They'll gnaw right through'

"Squirrel invasions" are extremely common in the city, said Woodcock, who has been in the pest control business in Edmonton for 12 years.  

"Every month is squirrel season in Edmonton," Woodcock said in an interview with CBC Radio's Edmonton AM.

"They don't care about anything, not even Christmas." 

It's one of those, don't do it yourself type things.- Joe Woodcock

If you suspect that you have a nest, act fast as the tiny critters can do a lot of damage in a short period of time, Woodcock said. Using their formidable teeth, they will chomp through electrical wiring, insulation, wooden furniture and beams. 

In the worst case Woodcock has seen, squirrels levelled an entire building.

"Someone had an old car that they had saved for years in the garage and the squirrels were upstairs and eventually the garage actually collapsed on the car," he said. 

"And even though the car wasn't worth anything, it was horrible for the old guy who owned it and thought he was going to restore it one day." 

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When blocking off any squirrel entrance holes in your roof and attic, rely on a professional. Leaving a squirrel trapped inside the walls of your house is a "worst case scenario," Woodcock said. 

A trapped squirrel is unlikely to perish from starvation. 

"The second to last thing you want is a squirrel trapped inside your house, because they will get out. They'll gnaw right through into your kitchen."

"It's one of those, don't-do-it-yourself type things."