Elegant birds. The large Royal Tern is the size of a small gull. They live on our East Coast ocean beaches, and nest on dry sand bars. Like all of our terns, they are highly migratory, and make their living diving for small fish. You can read about Royal Tern
here. Amateurs like me can easily confuse them with the
Caspian Tern in the field (that is, on the beach).