‘Shoots’ at stately homes attended by stars like cricket legend Ian Botham and rock guitar god Eric Clapton are adding to the problem which will plague the country in the hotter months, a study has found.
Staff at such homes are spreading corn in woods, grounds and moors, morning, noon and night to ensure they have enough pheasants, partridges and grouse to blast away at.
But the gamekeepers are putting food right into the mouths of greedy rodents, experts have said.
Earlier this year specialist pest killing companies warned people to stop buying over-the-counter poisons as a new breed of super rat have become immune to them.
Rats have been growing bigger than ever with massive rodents being discovered in the countywide and in the city – some over two ft long.
The game bird shooting season lasts from November to the start of March, just when food supplies in the wild run out for the monster rats.
They switch instead to the thousands of tons of grain which gamekeeper across the UK scatter in fields and woods for pheasants and partridges to feed on.
The corn is meant to keep the game birds in tip-top condition for the aristocrats and their celebrity friends – but often the rats get there first.
A new study, carried out by the Hampshire-based Game and Wildlife Conservation Trust, discovered that more than two-thirds of the food put out for pheasants and partridges is instead fattening up rats, grey squirrels and ‘pest’ birds such as pigeons and crows.
Other experts say the new breed of genetically-altered super rats are immune to available poisons and the numbers will leap to 200m this year unless an emergency plan is drawn up.
The mutants swarming across our towns, cities and countryside are twice as large as normal rats and cannot be killed with traditional substances.
Genetic testing by Huddersfield University has revealed that the rodents have developed a mutation that allows them to survive conventional poisons.
Simon Forrester, chief executive of the BPCA, said: “Reports of poison-resistant rats have been increasing in recent years and it seems likely that there’ll be a further surge in numbers.
“The trouble is that people who try to treat problems themselves are likely to be making the problem worse.
“Stronger rodenticides can be more effective, but most are subject to strict legislation and must only be used by professional pest controllers.
“So it has become very important to make sure infestations are treated by experts in the field.”
The super rats, which can be up to two feet long, carry bugs which can be passed to humans, including Weil’s disease, which can lead to jaundice and kidney failure.
Mr Forrester said: “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 could be a significant risk to public health if their population is left unchecked.
“Rats must be dealt with by a professional pest controller who knows the area in question and their likely habitat, and knows how to treat any particular strain.”
Tips for avoiding home infestation include keeping outside bins clean and well maintained, not leaving pet dishes outside over night or bird feeders and keeping gardens clean.