Just checked my backyard birders handbook. Red tailed hawks have just that, a red tail, chestnut brown. I would say that it is either a coopers hawk (chicken hawk) or maybe a broadwing hawk. They both have the white bar across the tail. It looks a little big to be a sharp shinned hawk. Plus, they have a slightly longer tail and are about the size of a mocking bird. Either one of the two will go after your chickens or small fowl. We have a coopers hawk that flies overhead once in a while and it will chase down our hens until they run into adequate cover.