The white tern is a seabird that catches fish by plunging into the water. what physical features of the bird likely make this feeding behavior possible?

White tern catches fish including crustaceans, flying fish, squid, and others. Prior of plunging into water, it hovers initially over the water surface and then either dives or dips in the surface, without getting entirely submerged into water, and catches its target.  

The food or fish is captivated in its small, however, sharp black beak that is specific as it bent upwards and tapers to a sharp point. It also possesses a long slender body with tapering, long wings, all of which encourage its diving or dipping activity into the surface of the water.