Figure 9.7 The shape of a seabird's beak is related to the kind of food iteatsand the bird's feeding style. (a) n tubenoses such as petrels (Pterodroma), the beak is relatively short, heavy, and hooked-an ideal shape for holding and tearing prey that is too big to be swallowed whole. Such a beak is best suited for shallow feeding because its size and shape interfere with fast pursuit underwater. (b) The beak is heavy but more streamlined in the razorbill (Alca), penguins Aptenodytes and others), and other seabirds that dive deeper to feed on crustaceans and other prey. (c) Terns (Sterna), boobies (Sula), and other plunge divers have a straight and narrow beak for feeding fish that are swallowed (d) skimmers nchops) e the only birds with a on whole. lower beak that is longer than the upper, which permits feeding while flying Shorebirds that eed on have a long, thin beak that allows them to get to prey buried in the mud (see 12.12