"I took into account for the possibility of it being a Cooper's Hawk, but ultimately rejected the idea."
Rejected the idea of a Cooper's based on these photo's? The two species are far too similar to reject one over the other. All we can safely do is give an opinion based on experience.
"I know that a male cooper can be of similar size to a female sharpie and I know that both birds have similar color phases to one another."
Correct. When you stated a Peregrine is far larger than the bird pictured you could not have been considering a female Cooper's at all. Instead, I took that as a clue as to what bird this could possibly be (Cooper's).
"When you look at the first picture -- it is the best shot of the bird in a natural profile pose compared to the other two photos with the head turned off kilter. My leanings toward it being a sharpie was this:
The legs are thin and yellow color is dull. Coopers have thicker and more noticeably bright yellow chicken legs."
The legs do not look 'thin' to me at all and the color cannot be ascertained by these poor quality photos.
"The head is more rounded and short where a cooper's would be a bit flatter and longer."
Absolutely opposite of what I'm seeing. The head is far too large to be a Sharpie in my opinion and has that flattish look I see almost daily in the Cooper's that's terrorizing my yard almost daily. I have photos of a Sharpie that crashed into my window that clearly shows the smallish head so indicative of this species.
"The beak is short/tucked in looking - not sticking further out like a cooper's."
This is something I've never noticed before. I've also never seen it mentioned in any of the guides I've seen. However; you've probably had more of these birds in hand as a rehaber than I have so I'll defer on this one. But again, from a poor-quality picture?
"The tail feathers appear more squared off instead of rounded (a little hard to see because they are splayed out a bit)."
Again, I see a long, roundish tail. However, this is a ruffled, upset bird. Can't tell from the photos.
"The tail feathers are lacking the noticeable white terminal band you would see in a cooper's. The terminal band you see in the photo is dark gray which is what you normally see in a sharpie (occasionally sharpies can have a very thin white tipping below the gray terminal band, but even that is not showing in the photo)."
I too don't see the whitish terminal band. But nothing definitive.
"The acrobatic behavior of the bird having flown through a window screen at high speed while chasing a songbird does not match the normal flight behavior of a cooper's, but does match the behavior of a sharpie."
This is incorrect. The normal flight pattern of all the Accipiters is flap, flap, flap....glide. They look awkward when just flying as in migration. However; all Accipiters display the high speed acrobatic behavior you state when chasing down prey. The Cooper's is particularly fast and powerful. The Sharpie is just a light-weight in comparison.
When you corrected the original poster what you should have said was this is an Accipiter species and in your opinion a Sharp-shinned hawk. From the photos and description you cannot tell for certain. This is why I stated it 'probably' was a Cooper's.
Thanks for the discussion. Birds are awesome.
Paul
