This is a Green Heron (affectionately known around my house as "Sparty"). (It might also be an American Bittern. Not really sure.)
Walking past the window (about 30 minutes ago), I saw this. That's a Great Blue Heron (affectionately know around my house as "Big Blue"). He didn't stick around long. The Red-Wings were harassing him because he's a predator. But I did manage to get a closer image: