Hawk

I was talking w/ my brother on the phone when a bird landed on a shepard's hook.  This was no goldfinch or redpoll.  It was a hawk.   The little birds took off en masse.   The hawk sat for a short time and then it flew off the opposite direction.  It looked like a Cooper's to me but I couldn't be sure.  My brother and I kept talking until I noticed the little birds were back at the feeders.  Suddenly the hawk was swooping through hot on the tail of a goldfinch.  The little bird zigzagged through the lilac bushes and got away.  The hawk landed on the ground just beyond the bushes.  Unceremoniously I said goodbye to my brother and grabbed for my camera.  The bird was in a hard to focus spot but I got a couple of pictures and then went to consult my Sibleys.  Turns out even w/ a picture it's hard to tell some birds apart.   I saw the red eye and thought it was a Cooper's.   However a  Cooper's and a Sharp-shinned are practically carbon copies of each other except one is larger than the other.  A Cooper's is about the size of a crow while a Sharp-shinned is the size of a blue jay.   However, because of different sizes of the males & females in both species a small male of a Cooper's looks about the same size as a large female of a Sharp-shinned.   I checked on the maps where these birds should be this time of year.  That didn't help either.   Neither is normally here in the winter but both birds had year-round areas just south of here - maybe 100 miles.   Sent a picture over to my neighbor Doug.  He knows birds better than I do.  He is of a mind that it's a Sharp-shinned.  I still think it's a Cooper's (maybe).  Either way now I'm feeling a bit guilty for practically hanging up on my brother.