But... he seems to have the squarer head with cap of the Cooper's and the more rounded tail?
Perched raptors can be tricky, even for iindividuals that see lots of raptors. I don't consider myself to have great expertise with images of this type, but will take a shot at describing what I see here.
Rounded tail - The appearence of a rounded tail seems to be do to the considerable amount of molt occurring on this bird. If you look closely, you should be able to see that the outer tail features are still growing in. Molt is evident on the wings as well.
Squarer head - There is some indication of a squarer head. However, this bird appears to have its head and neck featheres fluffed up. This could account for the squared and capped appearance.
Facial expression - When I look at this gal (I believe it is a female), she has a rather bug eyed expression typical of Sharp-shins.
Legs - The "shins" of this bird do appear substantial. However, I have been fooled by this before :(
Body shape - Coups tend to have tubular bodies. Sharpies and Goshawks tend to be much more chesty. I can't say much either way for this bird (another bummer).
Putting it all together - The tail and head shapes seem to be do to the state and position of the bird's feathers. The facial expression suggests Sharp-shin every time I look at the image. Nothing else leans me strongly in either direction. This leaves me thinking that is a young female Sharp-shin (hatched year 2017).
Perhaps someone with greater experince with perched accipiters will have a different opinion.
Thank you very much, Todd. I hadn't thought about most of those pointers and will take them into consideration if there is another visit. No doubt you have it right :) I see that Joanne (below) agrees.
Hi Gail, my over all impression is an immature Sharp-shinned Hawk in the process of molt. Coarse brown streaks on Sharpie, thin dark streaks on Cooper's. The legs look thin and the eye seems to set back further than one would suspect with Cooper's.
Thanks, Joanne. I hadn't thought about molting but did feel that it was smaller than the Cooper's I had visiting last year.
FYI - Fine or coarse streaking on accipiters refers to markings on the chest. This individual is barred. Coups tend to be finely marked (more coarse or heavily in the west), sharp-shins and goshawks tend to be more heavily marked (goshawks can be somewhat variable). Also - Streaking on immature goshawks extends into the undertail coverts. On other accipiters, it does not. Most of this isn't relivant here, but is useful info.
There is a Raptor ID Facebook page that can be extremely useful. There you will see some nice photos as well as some great comments on plumage features and other fine points. Some of its contributers make my feel like a beginner!
Thanks, Todd, I will check that out. No fear of me feeling like anything but a beginner :)