This was challenging. I almost gave up, but tried again tonight. I cloned bits here and there, adjusted the bill and replaced whatever he was eating with a beachball.
ETA:
More explanation... I used the selection tool to select bill, then copied to a new layer. Used transform to adjust so that it was open wider, then cloned out original bill location.
Lightened shadows and brightened.
Used selection tool on eyes and yellow cap, then adjusted hue and saturation.
Used circle selection tool to select oval and copied to new layer. Added bevel. Darkened bottom layer and flattened image. Added outline.