I have my girls in an enclosed run since I have dogs and don't trust them. I pen the dogs and let the girls free range on occasion. Yesterday I put the dogs up and let the girls out. Within seconds crows were making a huge raucous. Then a huge hawk came screaming through the sky. The crows were working together to get it out of their territory. Then suddenly another raucous across the road and a huge turkey vulture was on the hunt. Again, the crows were on it!! Now, I have heard how chickens take note of such activity and will run & hide from hawks. Not so!! Maybe three hens ran into the coop, the rest just continued as if nothing was going on, including the rooster! We sat down there to discourage any hawks from taking a chicken off into the wild blue yonder. Do I have the only chickens with no natural instinct???????