I recently had a Cooper's hawk attack a one y.o. Wyandotte hen. The hen is slightly smaller than her peers, but still much larger than the hawk in question. I live in NH with a combination of open pasture land and heavily forested land. My chickens usually hang around in the brushy areas, so I figured they were safe from air-borne predation because they were under pretty heavy cover. I was mistaken. I have seen this tiny hawk swooping through the tree canopy like a rocket. It flies like it's on a suicide mission. Very quick! And the damage it did to my hen was devastating. Because they are much smaller than your typical hawk they do not "swoop and grab", they will land on their prey and try to squeeze them to death with their talons. This hawk has been the most successful of all the predators we have. Do not let their small size fool you. Dynamite comes in small packages, too.