Here a Common (or Brown) Noddy has picked seaweed from the water for nest material and a Black Noddy is trying to make it drop the weed so it can pick it up. The shot also is a good comparison between the two species. The Black Noddy is a smaller bird which makes it look like it is behind the other, but it was above it.
1DXII 70-200mm f/2.8L II & 2xIII 400mm 1/2500 f6.3 iso320