....Thanks for explaining that to me
I rarely apply any noise reduction to a bird or other wildlife and after any post-processing in Aperture I edit in Photoshop CS6 where I select the subject (bird etc), invert the selection and then apply a third-party noise reduction filter (Imageonic) to the background
only before Smart Sharpening as the last step. This is because I don't like the look of over smoothed feathers/fur etc because I think it looks unrealistic.
I'm very grateful for your advice on this but am afraid that I am happy with this particular image in the circumstances and it's not for the bin yet. I wish I could see the "colour noise" you are referring to. I have viewed the image on my 27" Mac display.