All About Birds has this to say about the Cooper’s Hawk (Accipiter cooperii):
Among the bird world’s most skilful flyers, Cooper’s Hawks are common woodland hawks that tear through cluttered tree canopies in high speed pursuit of other birds. You’re most likely to see one prowling above a forest edge or field using just a few stiff wingbeats followed by a glide.
You can hear the call of the Cooper’s Hawk at that link and they say that if one of these birds starts treating your bird feeder like a take out, just remove it for a few days and it will move on. More at Wikipedia’s page on the Cooper’s Hawk and at Accipiter cooperii: Cooper’s hawk from the UM Animal Diversity Web.
See this bigger in Renee’s slideshow.
Lots more Michigan birds from Michigan in Pictures!