Nice colors and detail in the legs and foreground. In addition to taking out the dark spots near the head, maybe you could also remove the crescent-shaped dark spot behind the bill. It's a fine photo as is, but that would put it over the top.
really cool image Glenn, the bird has some cool lighting, did you use a flash? very interesting environment, I don't mind the background and stuff in the water, it helps balance the image imo.