Wanted to put my 2 cents in, as the owner of 3 bengal cats, your cat very much resembles one....my male cat will follow me around the house "growling" when he is anxious and something has spooked him. They are known for making these sort of noises when they are unsure about something and some just Talk a lot. I actually don't think your visiter is being mean or viscious, I think he/she is either a bengal or certainly a bengal mix. They are normally good size cats, they are a very friendly but have a bit of a wild side to them, mine are into Everything! Anyway, I would hate to see that animal killed and Im glad you dont want to go that route. I doubt very much he is killing your chickens, it sounds like a raccoon...Anyway good luck and I would do as you said and feed him well and the fact that he follows you like that tells me you can easilly tame him. If he were wild he wouldnt go anywhere near you, he is trying to befriend you in his own way. My female bengal looks Exactly like your cat, it could be her, so I think that's what you have.