I like the closeness of this shot. It shows nice detail, especially in the water drops. The DOF is good. I like how the tops of the far grapes are softer focus and everything else is in great sharp focus. Lighting is perfect. Nice even lighting throughout. Color is great as well.
The only thing that I see that could be something to try differently would be the seperation of the photo. The 'seperation' line is directly in the center of the photo. Left 1/2 of the shot (from tip of ducks beak leftward) is heavy and dark in color, and the right side (from tip of ducks beak rightward) is bright in color. Puts a lot of weight on the left side of the photo.
Other than that, for a shot of a duck with 5 grapes in water on a blue background, this is a very nice shot. I really see no need for major improvement anywhere. Very nice job. ~Heather~