Nice image Ian - the location looks vaguely familiar... Really nice feather detail, but I would "richen" up the blacks a bit (maybe some "Selective Color" black added to the Blacks). I like how, even though we can't see the pupil or a significant catchlight, that ruby red eye still pops and draws our eyes right to it. Given the pose, I would definitely consider a tighter (or vertical) crop. If it were mine I also would experiment with raising the colour temperature a bit (or increasing the yellow saturation of the water) for more of a golden background.
I like all of Jeff's suggestions, Ian, but I do also like the image as presented from a crop standpoint. One other suggestion would be to darken the rock he's standing on a bit so it separates it from the water in the BG.
Love your choice of ss and aperture - good depth on the bird with a nice, soft, fluid BG. Only other suggestion would be to have moved a bit to the left in the field to get more of a sideview of the head against those black feathers.
This is nice Ian. Love the warm light and overall warm tones. Very unusual pose- I like it. The image really shows off the "rail" feet (the feet start at the dark ankle joints right below the body). Agree the blacks could be darkened some, so long as the detail is retained.