I'm sure I just saw a swift fly by my Manchester flat on what has been a lovely sunny day; a couple of years ago, one got trapped in my small juliet balcony, as has a pigeon, both of which I had to help out. I was worried about handling the swift but no need - it was a muscular little thing and once above the balustrade didn't waste any time taking off!

Thus, I now have a plastic peregrine falcon on one side, and a wooden duck on the other (if an English pub, it might be called The Duck and Falcon), which seems to have done the trick.