Cats Protection in Bournemouth has been setting traps in a Fordingbridge car park to catch felines for use as rat-catchers. The charity neuters the cats before sending them out to farmers.
It is appealing for more people to help look after the animals. The cats will never be tame enough to become household pets so their perfect environment is stables, farms or garden centres, the charity said.
Sittingbourne shelter manager Carole Milward commented: "Feral cats tend to prefer the rigours of the outdoor life to a comfortable lap in suburbia. They can provide a very efficient and environmentally-friendly alternative to chemical pest control."
Cats Protection estimated the current UK feral cat population at around 1.2 million.
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