The increased breeding of rats and mice over the long hot summer is leaving Northland businesses and homes plagued with rodents this winter with supermarkets, butcheries and schools needing pest control.
The rodent problem is likely to affect people more in winter with rats and mice heading indoors seeking food and shelter.
"When it gets a little colder the plants die. They lose a lot of their food source so they come into contact with us more," said Lindsay Grant from Jae Pest Control who operate out of Whangarei and Kerikeri.
"Rodents are a consistent problem anyway [but] the long hot summer has allowed rats and mice to breed well. There has been an increase in populations."
The problem will persist this winter because the good conditions this summer allowed rodents to breed.
"Nests usually get destroyed by rain and water, that didn't happen," he said.
Mr Grant said his business has experienced an increase in call-outs for and enquiries about rodent control.
He said at least three calls a week from businesses including supermarkets, butcheries and schools seeking help with rodents.
Rodents are problem because they can cause health problems including the infectious disease leptospirosis - primarily a disease of wild and domestic animals - humans are infected through direct or indirect contact with infected urine.
As well as the risk of picking up an infection from the rodents, they can chew through electrical cables causing fires and gnaw through water pipes causing flooding.
The Far North has been affected by the increase in rodents with the Advocate publishing a story yesterday about rodents being a problem in Kaitaia with children sleeping close to the floor on flimsy mattresses.
Mr Grant recommends households and businesses take precautions to discourage rodents from getting inside.
"Be aware of leaving pet food out. Keeping the yard clean will help prevent habitats [for rodents] to breed."
He said trees and vegetation close to buildings allow rodents an access route to roofs and then into ceilings.