The brown booby is a large seabird belonging to the gannet family, usually found in the islands near the Caribbean Sea. It is mainly a waterbird, and named after its brown colored feathers. This bird has been known to plunge from great heights when feeding. They are generally quiet, although bird experts have reported gull-like noises from them.
Characteristically covered in dark brown feathers, the brown booby has a few white streaks on the belly or wing linings. The head is completely black and the beak is jagged but very sharp. Its wings are short, narrow, and pointed, but the tail is long.
The females are distinguished with yellowish feathers and the males have green-gray streaks with bluish undertones on the throat. The young are covered in brown feathers, with the bare parts colored in dull gray. The bellies of the young have distinct lines running down from the chest.
These birds mainly survive on squid and flying fish, which they hunt by plunging from the sky and diving into the ocean. The brown booby usually forages in broad daylight and often just inside its breeding grounds. They fly at high speed and are very powerful in the air, but their landings and takeoffs are not at all graceful.
Between March and November, brown boobies breed in shallow, depressed areas with some vegetation along the shorelines. High-pitched whistles from the male and quacking and honking sounds from the female usually mark mating rituals. These birds preen and touch beaks when courtship takes place and usually remain paired up for many years.
A brown booby lays an average of two to three eggs, with the parents taking turns incubating the eggs for a period of 43 days. Hatching intervals between eggs last several days, and young boobies are characteristically helpless and blind at this stage. Feeding is done every 17 hours for about two months.
The brown booby's population has declined since predators, like rats, have become more numerous in areas where they live. The human population has also overtaken much of their habitat. Their last known nesting ground was discovered in the 1960s. Brown booby colonies have receive protection in some areas, such as the coast of the United States and the Gulf of Mexico. Their numbers, however, continue to decline in the Caribbean and the coastlines of Central America.
Brown boobies are referred to as congress, trap, or hatch when indicating a collective group. They are often compared to pelicans, ducks or geese. The brown booby can survive for 25 years.