These birds return southward to warmer waters by winter. Small numbers of immatures regularly wander inland in summer, especially in Southwest. Habitat Salt bays, beaches, ocean . Nests on islands, which may be either bare and rocky or covered with mangroves or other trees. Strays may appear on freshwater lakes inland.
Types of fish known to be important in some areas include menhaden, smelt, anchovies.
Also some crustaceans. Tilts bill down to drain water out of pouch, then tosses head back to swallow. Sometimes scavenges and will become tame, approaching fishermen for handouts. Nesting First breeds at age 3 years or older. Nests in colonies.