Types of rats and mice which have developed resistance to poison could be on their way to Nottinghamshire, pest controllers say.
Rodents which over time have become immune to some traditional pellets have already been found in London and Birmingham.
In some cases the animals have become so immune they simply eat the poison like food and grow bigger.
And the British Pest Controllers Association fears with winter on the way the pests are heading indoors where they will cause more problems for homeowners.
Simon Forrester, the association’s chief executive said: “The rodents have become resistant and, in some cases, immune to off-the-shelf poisons.
“Normal rats are being killed off by poison, so these resistant species are taking their place. It’s only natural that their numbers are expanding and there would be a significant risk to public health if their population is left unchecked.”
But Nottingham City Council says it is expecting a normal season for infestations and encouraged anyone concerned to use its free pest control service.
I actually saw mice running off a pallet direct from the back of a lorry
Ryan Doyle, founder of Nottinghamshire pest control firm RKD, said he’d heard of instances of resistant mice locally and warned they are spreading.
He said: “I’ve heard of resistance to poison happening in Nottingham, although I’ve never come across it myself.
“But the problem is spreading further north. I know there have been reports of it in Birmingham.
“You do get problems with supermarkets and stocks of food arriving on lorries, that can be how rodents move around the country.
“At one job I actually saw mice running off a pallet direct from the back of a lorry which had been opened.”
He added rats and mice can be kept under control by good hygiene, and encouraged the public to store waste securely and monitor empty buildings carefully.
Lorraine Raynor, chief environmental health officer at Nottingham City Council, said: “There is absolutely nothing to suggest that this year is going to be any worse than normal for rat infestations.
“We offer a free pest control service for rat infestations both inside and outside for all domestic properties.”
Video: Notts people give their views on the spread of urban rats
