I heard if you feed the hawk pineapple. Oh wait~that is for poop eating puppies.
I'm sorry I just had to say it.
In all seriousness, all the things that you mentioned are what I have heard will help to deter my jet plane size hawk from hanging out in your yard. I don't even think a hawk has a natural predator to use as a deterrent. I just tried to Google search too. I still vote for the CD's in the trees and sequin outfits would work the best. You might just need to make him want to move on for a few days he will find a new place to hang out.
The one that was hanging out in my yard eventually let after giving me several heart attacks a few weeks ago.
