Have you ever wondered why a bird that is such an elegant flyer and diver is called a booby? The name “booby” comes from the Spanish word bobo, which means fool or jester. Boobies are clumsy on the land, and like other seabirds can be very tame. Although they are powerful and agile fliers, they are particularly clumsy in takeoffs and landings; they use strong winds and high perches to assist their takeoffs.
In the Caribbean the most common booby we see is the Brown Booby, which of course is not all brown. Its head, upper body and back are dark brown, with a sharply contrasting white belly. The bare facial skin around the bill may vary in color by region, sex, age, and time of year. During breeding season males usually have blue skin around the bill, and, as in the photo, females have yellow skin with a dark spot in front of the bill. The feet and bill vary and may be bright yellow, pink, or grayish. Juveniles are grayish brown on the back with slightly darker head, wings and tail. Their belly is mottled brown and white. The adult brown booby reaches about 76 cm. (30 in.) in length.
Boobies plunge-dive from heights up to 15 m (50 feet). The dive starts with wings folded next to body, and as the bird approaches the water the wings are thrust straight out over its back, touching in the middle. A dive may reach just below surface, or to as much as 2 m (6 feet) deep. Brown Boobies commonly feed in areas where large predatory fish such as tuna drive smaller fish to the surface. They feed on squid and small fish, especially flying fish. They can use their feet and wings for underwater propulsion.
The Brown Booby nest is only a small depression, sometimes lined with grass, bones or other bits of trash. The nests are on the ground usually on islands, covering a wide range of vegetation types and geologic features. There are usually two eggs laid and incubation lasts for 43 days. More often than not, only one chick survives to fledge after 85–105 days. The chick is then cared for another 118–259 days. They do not breed until they are two to three years old. Brown Booby pairs may remain together over several seasons and perform elaborate greeting rituals.
Although Brown Boobies are common in many areas in the Caribbean, development and predators have caused severe population declines over the past century.
Devi Sharp is a retired wildlife biologist exploring the birds of the Caribbean with her husband Hunter on their sailboat, Arctic Tern. Chuck Shipley is a former professor of computer science and an avid amateur photographer. He and his wife Barbara live aboard their trawler, Tusen Takk II, in the Caribbean.