Combine a global pandemic and a warm winter and you get … rats?

What do you get when you combine a warm winter and a pandemic that keeps people in their homes? More rat sightings, apparently.

Craig Walker, the owner of Walker's Livestock Feed & Supplies in Cole Harbour, N.S., said his customers, many of them farmers, often have issues with rats in the fall and spring, "but this winter it never slowed down."

"The consensus is, due to the very mild winter without any snow, the rodents had a very easy time finding food and they never slowed down their breeding habits," told CBC's Mainstreet on Thursday. "It added up to an increased rodent presence for sure."

Walker said he's also heard from customers that this is the first year they've ever spotted rats on their property.

Andrew Hebda, the retired curator of zoology from the Nova Scotia Museum of Natural History, has been hearing similar stories.

"Certainly the rats have been not only present, but a little bit more visible this winter because it's been a mild winter. We haven't had any snow cover," Hebda said.

During colder winters, Nova Scotia's brown rats will typically find a warm place to nest — whether it's inside old cars, homes or sheds — with extra snacks to wait out the low temperatures. But this year's warm weather has allowed them to thrive outside during the winter months.

But it's not just the higher-than-normal temperatures that have Nova Scotians seeing more rodents.

The increase in sightings can be blamed on the COVID-19 pandemic. Hebda said with fewer people leaving their homes due to public health restrictions, less waste is being created in areas where rats typically live.

"Many of the rats that would normally be residents in and around fast food establishments have now been forced to go further afield, to go for food," he said, referencing a study conducted by the British Pest Control Association last year. 

"So people are seeing rats in places where they hadn't seen them before."

'Don't give them an invite'

Walker said rodents can cause "astronomical" damage in a short period of time. 

One of his customers, Jan Glazebrook, had her vehicle destroyed from the inside after rats chewed through the wiring.

"The solution everybody seemed to give me was to put Irish Spring soap in your car and in your house because they don't like the smell of it and it'll keep them away," Glazebook told Mainstreet. "And I've not seen a rat since."

If you do spot a rat on your property, Walker said there are a couple of things you can do to prevent them from sticking around.

"The biggest thing you can do is don't give them an invite — don't give them a food source," Walker said.

Walker advised people to keep excess food off the ground, like chicken feed and bird seed. Compost bins should also be sealed properly to keep rats out.

He also recommended using bait stations to eliminate rat infestations, but advised against using traps.

"Trapping is another option, although I find with trapping rodents, you'll never stop trapping them because of the way they breed," he said. "Trapping never seems to be a way to to eradicate the issue."