While walking the dog l have witness numerous times a kestrel swooping on its unsuspecting prey. It is something you don't expect to see from you kitchen window. One morning while looking through the window imagine my surprise when l saw a hawk or kestrel swoop at my birds in the outside flight hitting the wire on my outdoor flight with such force it a wonder the bird did not break it's neck.
The birds did not seemed fazed by the attack and within a minute carried on as nothing had happened the bird left disappointed uninjured and still hungry.
My outdoor flight at Trafalgar is made of aluminium angle panels bolted together with stainless screws. If you are using wooden frame panels it would be wise to double wire your panels as budgerigars really enjoy a good chew on any wood they can find.