[maxthecollie]

Originally Posted by kestrelx

Even well fed cats kill birds as they don't do it for food.
Some one said a powerful water pistol will get rid of cats after repeated use (and it doesn't kill them) - as they don't like water. But a more expensive answer, though I haven't tried one, is the RSPB sonic cat deterrent:

Catwatch Cat deterrent | RSPB Wild Bird Care | RSPB Shop

Jet wash works for me