Who is my guest?

Raven

Crow

I'm not certain if it is a crow or a raven that came today.  If he comes back tomorrow, I have to really pay attention to the beak and the shape of the body.

A similar or the same bird came to my office window for weeks last year, jabbering and peeking at the glass. 

I was so curious I rang up the Cornell Lab of Ornithology and spoke to the crow expert.  He may have lost his mate and is searching for a new one.  The crows generally travel in pairs.