Bird Watching: What kind of bird is this, 1 by plantzoo

plantzoo wrote:
While my kitties were sunning themselves by the window there was a loud noise. I found this guy had hit the window,( I think he thought he was going to have kitty for lunch). It laid upside down with it's feet in the air for 2 hours! Then it stood up and 15 minutes later it was gone. At first I thought it was a Merlin, but according to my book they don't live in northeast Wisconsin. Any idea what this is?
Bev