Excellent image. Very nice pose with raised foot and crab in the beak. I like the artistic sand,lights and composition.
Agree with John about spots in the BG.
Love seeing the plover with the little crab. I would try cropping as much of the water out as possible since it's not adding much to the image and distracting the viewer's eye from this cool bird with prey.
Hi Jon, well exposed on this fellow, the colours show up nicely. Good low shooting angle, and great seeing the catch. Comp wise, I would take off the top as Marina suggested, but just above those dots, and then blend those dots away.