There are more than half a dozen species of pelicans, but all of them have the famous throat pouch for which the birds are best known. These large birds use their elastic pouches to catch fish—though different species use it in different ways.

Many pelicans fish by swimming in cooperative groups. They may form a line or a "U" shape and drive fish into shallow water by beating their wings on the surface. When fish congregate in the shallows, the pelicans simply scoop them up. The brown pelican, on the other hand, dives on fish (usually a type of herring called menhaden) from above and snares them in its bill. Pelicans do not store fish in their pouch, but simply use it to catch them and then tip it back to drain out water and swallow the fish immediately.