It was down a rabbit hole, those of us who actually hunt allow their ferrets to enter holes and do what comes naturally to them. As I said I wouldn't knowingly enter a ferret to a cat, sometimes in the countryside ferrets come up against various critters which reside in rabbit holes, i've dug to hedgehogs before and bolted stoats, rats, shellducks and mice never bolted a fox but plenty of people have along with feral cats too. My mate was pleased to have killed it, he helps out with the keepering on the shoot and its one less predator on the ground. You say that ferrets kill slowly (is this fr