Is he getting out of a pen or is he escaping your actual yard? Maybe netting or more chicken wire across the top for the pen? If its your yard, I'd suggest maybe a low power electric fence wire along the top but only if he's actually hitting the fence... won't do much good if he's flying over it ;-)

And bread.... want!! I havent been making bread for months because of the heat but once it cools off outside, watch out! :-p