flocking nuts
Chirping
only thing that can be done is put your chickens in a bigger covered flight pen ,and those are expensive, , hawks and owls have more rights than we do so our hands are tied ,just do your best to provide cover for them to duck under ,ive heard coyote decoy may keep hawks from diving in because in the hawks mind it may become lunch also ,good luck.
I wouldn't want to do anything to harm a hawk or owl. I would feel terrible.