[squiggler]

Okay, crit...your tail is absolutely beautiful, and so are the transitions in it, but the underside of the beak/mouth is a bit jagged. I can tell there are stray pixels in there and I think you should have used grey-toned pixels to create a softer edge. The back flipper doesn't have complex shading/texture at all and looks unfinished because of this. I love your eye and the texture of the beak. Your shading is really good though you might want to put some on the upper part of some of the flippers.

ETA: Just noticed, where are the opposites of the other flippers? You might be able to get away with not having them but a sliver behind the others could be nice.