A cat has been hanging around my garden lately. He looks like a young, entire male. He is a bit thin and seems on the prowl for food. Today he was chased off by one of my cats. He really didn’t want to go 
I often feed one of my cats outside the back door because he is very nervous of being indoors and I think this is what has attracted this cat.
I obviously need to stop this as it’s upsetting my cat (who is quite anxious) but at the same time I’m a bit worried about the poor little thing.
Any advice?