Tropical seabird of the genus Sula , in the same family, Sulidae, as the northern gannet , order Pelicaniformes. There are six species, including the circumtropical brown booby S. leucogaster .
Plumage is white and black or brown, with no feathers on the throat and lower jaw.
They inhabit coastal waters, and dive to catch fish. The name was given by sailors who saw the bird's tameness as stupidity. One species, Abbott's booby , breeds only on Christmas Island, in the western Indian Ocean. Unlike most boobies and gannets, it nests high up in trees. Large parts of its breeding ground have been destroyed by phosphate mining, but conservation measures now protect the site.