This image was made at Sanibel island. I had just gone to the beach and saw this great white with this fish, which after some turning and tossing in its beak it swallowed it. The bird was not far away and I had the 400 f5.6 so could get a closeup. The BG is of the sea in the background.
Canon 30D with 400mm f5.6 at f7.1 1/3200s at ISO 250
After making this image, your next step would have been to move the the other side and get in a position where your shadow is pointing towards the bird. You lighting would be a great improvement.
I like how the two are looking at each other here. An interaction between the hunter and the prey well portrayed.