Richard Baudains, who owns the Le Pepinière Farm in Rue de Crabbé, says the animals, often wrongly described as polecats, are killing significant numbers of chickens and ducks.
One of the Island’s pest control officers said the number of feral ferrets he was catching had increased tenfold in the past decade.
Cris Jolley said that he had caught 20 in the past year, compared with two a year a decade ago.
The problem has got so bad that one farmer said that he had contacted the Environment department to complain about it, but said that nothing had been done.
Mr Baudains said that he had caught four ferrets in the past two months and another two on Sunday night.