The Brown Booby (Sula leucogaster), is a large seabird that breeds on islands and coasts in the pan-tropical areas of the Atlantic and Pacific oceans. They frequent the breeding grounds of the islands in the Gulf of Mexico and the Caribbean Sea. It winters at sea over a wider range.
The adult grows to about 30 inches in length. Its head and upper body are covered in dark brown, with the remainder being a contrasting white. Juveniles are grayish brown with darkening on the head, wings and tail. Although typically silent, these birds have been reported by birdwatchers to occasionally make grunting or quacking sounds.
This bird nests in large colonies, laying two chalky blue eggs on the ground in a mound of broken shells and vegetation. Brown Booby pairs may remain together over several seasons. They perform elaborate greeting rituals. They also are spectacular divers, plunging into the ocean at high speed. They mainly eat small fish or squid which gather in groups near the surface and may catch leaping fish while skimming the surface. Although they are powerful and agile fliers, they are particularly clumsy in takeoffs and landings. They are assisted in takeoffs by high perches and gusts of wind.