I love the backside view here.
I also like the BG, the frost on the perch, Comp and angle.
The right side of the perch is a bit bright on my monitor.
It seems that the shoulder / back / wing are the sharper parts.
Love it. The bird is excellent, unusual pose but works well. Great feel.
I would get rid of the blob/patch in the BG just above the birds back.
It is a bit distracting, otherwise it is a great image.