Finding its way in for this rat meant gnawing a large hole through a plastic waste pipe leading down from a ground-floor toilet, judging by signs of biting around the area.

According to the website, Britain’s rat population surged by a quarter to an estimated 150 million last year.

“I’ve been working seven days a week since the lockdown” started in March last year on up to 12 jobs a day, Sims said.

Dark and safe

Britain is on its third lockdown since the pandemic took hold, which has provided ideal breeding conditions for rats.

“With lockdown, you’re going to have buildings that are quiet, unoccupied, so it’s going to be dark, it’s going to be safe so they can breed undetected,” Rentokil manager Paul Blackhurst said.

Deprived of the food scraps thrown away at the back of buildings or in now abandoned city-centre streets, the nocturnal pests are also daring to venture out more.

There have been increased sightings of rats in broad daylight, strolling around residential neighbourhoods where rubbish bins of housebound residents are quicker to brim over in lockdown.

“If we change our behaviour then they are more than likely going to change their behaviour, because they are very, very adaptable animals,” Blackhurst said.

In rats’ ravenous and never-ending quest for food, nothing resists their sharp incisors, leading to damage to wood, brick and even electrical cables, raising the risk of fire and floods.

“They just chew through it into the building,” Chris Sherriff, of Beaver Pest Control, said as he inspected broken pipework under the front yard of a north London house.

Sherriff’s colleague, David Lodge, joked that the rodents’ increasingly brazen behaviour was like “a Stephen King novel”.

Gnawing through cans

With so many more people working from home, Lodge said residents were more aware of the problem in their neighbourhoods, which has grown worse in the winter months as rodents seek refuge from the cold indoors.

Others are in for a shock when they return to dormant premises.

Natalie Bungay, technical manager of the British Pest Control Association, described the case of one restaurant in western England.

“When they opened the doors, there were cans of food everywhere. The rats are gnawing through the soft metal, so it’s not really a problem for them,” she said.

With coronavirus rates falling thanks to a mass vaccination drive, Britain intends to exit lockdown by the summer.

That raises the prospect of more business owners re-entering shops and restaurants to find the messy remains of marauding rodent revellers.

Colin Sims says the vermin business shows no sign of letting up.

After dumping his plump dead rat in a trash bag for incineration, he drives his pickup truck to his next job, an infested commercial backyard.

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