Kept hearing this bird from my back yard while in my garden. I followed the sound and found the flicker high up in a dead elm tree.
Image made with Canon EOS 10D, 1/500 at f/7.1 ,ISO 200, with a Canon 100-400 IS Lens
I live in Michigan, and hope to see my local flickers and pileateds nesting soon.
A couple of points. For me, the bird is a bit too centered in the frame. I would crop a bit from the right, to move it off dead center, and crop up a bit from the bottom edge as well.
I think it could stand just a bit more sharpening. The trunk seems marginally sharper than the birds head, so consider another round of USM.
The angle of inclination is a bit steep, but hard to do much in this situation. I might have tried a step or two to my right if possible, to see if I could get the head against the clear sky.
In general I think its done well, I agree with Randy's comments as well.
I would like to add that I think the stepping to either side would have worked to get the flickr's beak more on the wood or the head more on the sky. Just my personal taste to how I like to see these guys,
For me, they seem to be tough to get in very sharp focus on the eyes SOOC as they seem to always be moving the head around (I have a red bellied pair in my tree).
Good comments above. I would add that the head is angled slightly away from the viewer - best to have it at least parallel to the sensor plane. I also see some cloning stamp tool smudges in the sky, along the trunk, and on the trunk (especially under nest hole and LRC, including repeating patterns) that need to be cleaned up.