The blue-footed booby is a comical-looking tropical seabird.
It is one of six species of the genus Sula – known as boobies.
The blue-footed booby is native to subtropical and tropical regions of the eastern Pacific Ocean.
It can be found from the Gulf of California south along the western coasts of Central and South America to Peru.
The blue-footed booby has an average lifespan of about 17 years.
It is large seabird on average 81 cm (32 in) long and weighs 1.5 kg (3.3 lb), with the female being slightly larger than the male.
Its wings are long, pointed, and brown in color. The neck and head of the blue-footed booby are light brown with white streaks, while the belly and underside exhibit pure white plumage.
Its eyes are placed on either side of its bill and oriented towards the front, enabling excellent binocular vision. Its eyes are a distinctive yellow, with the male having more yellow in its irises than the female.
The blue-footed booby is a specialized fish eater, feeding on small schooling fish such as sardines, anchovies, mackerel, and flying fish. It will also take squid and offal. The blue-footed booby hunts by diving into the ocean after prey, sometimes from a great height, and can also swim underwater in pursuit of its prey.
It can hunt singly, in pairs, or in larger flocks. Boobies travel in parties of about 12 to areas of water with large schools of small fish. When the lead bird sees a fish shoal in the water, it signals to the rest of the group and they all dive in unison, pointing their bodies down like arrows.
When one bird in the flock spots a fish, it gives a whistle to alert the others. Then the rest of the flock follows the first diving, into the water with perfectly synchronized movements. Interestingly, the male and the female are adapted for catching prey of different sizes. The male, being smaller, performs shallow dives, while the heavier female is able to make deeper dives farther offshore.
Plunge diving can be done from heights of 10–30.5 m (33–100 ft) and even up to 100 m (330 ft). These birds hit the water around 100 km/h (60 mph) and can go to depths of 25 m (82 ft) below the water surface.
Blue-footed boobies make raucous or polysyllabic grunts or shouts and thin whistling noises. The males of the species have been known to throw up their heads and whistle at a passing, flying female. Their ritual displays are also a form of communication.
Males use their bright blue feet to attract a mate! They display their feet in an elaborate mating ritual by lifting them up and down while strutting before the female.
The blue-footed booby usually lays one to three eggs at a time. The species practices asynchronous hatching, in contrast to many other species whereby incubation begins when the last egg is laid and all chicks hatch together. Blue-footed booby chicks have black beaks and feet and are clad in a layer of soft white down.
The blue-footed booby is one of only two species of booby that raises more than one chick in a breeding cycle.
Breeding pairs number under 40,000 and half of this population resides on the Galapagos Islands, where the species is legally protected.
Toward the end of the 1990s, concerns that the booby population was declining on an archipelago-wide scale prompted a call for periodic, comprehensive studies to assess the population size, understand the
cause of the decline, and inform necessary conservation actions.
Blue-footed boobies have no natural predators on land and few natural predators at sea. Furthermore, they are naturally quite curious. Therefore, they typically do not become alarmed if approached by people on land, and they often land on boats to explore people while at sea.
The blue color of the blue-footed booby’s webbed feet comes from carotenoid pigments obtained from its diet of fresh fish. Carotenoids act as antioxidants and stimulants for the blue-footed booby’s immune function, suggesting that carotenoid pigmentation is an indicator of an individual’s immunological state.
The blue-footed booby got its name from the spanish word bobo, which means stupid fellow. Its lack of fear and clumsiness on land has made the species vulnerable to man.