Blue-footed Booby

The Blue-footed Booby, Sula nebouxii, is a marine bird of the family Sulidae, easily identified by its vivid blue feet—a trait derived from its diet and used in mating displays. The female, slightly larger than the male, can reach up to 90 cm in length with a wingspan of 1.5 meters.

Identification Tips

Adults have long, pointed brown wings, a light brown neck and head with white streaks, and a pure white underbelly. Their eyes are yellow, with males exhibiting a more intense hue. Chicks are covered in soft white down with black beaks and feet. The subspecies S. n. excisa from the Galápagos is larger with lighter plumage around the neck and head.

Habitat

The Blue-footed Booby's natural breeding grounds are the tropical and subtropical islands of the Pacific Ocean, where it nests in large colonies on bare black lava.

Distribution

This species ranges from the Gulf of California down the western coasts of Central and South America to Peru, with approximately half of all breeding pairs nesting on the Galápagos Islands.

Behaviour

The Blue-footed Booby is known for its elaborate mating dance, where males display their blue feet and strut before females. They are monogamous, potentially bigamous, and opportunistic breeders with a cycle every 8 to 9 months.

Song & Calls

These birds communicate with raucous grunts or shouts and thin whistling noises, with mates recognizing each other by their unique calls.

Breeding

Courtship involves the male showing off his blue feet and performing a dance that includes "sky-pointing." Females lay two to three eggs, which are incubated by both parents using their feet for warmth over a period of 41–45 days.

Similar Species

The Peruvian Booby (Sula variegata) is similar but has grey feet, a whiter head and neck, and white spots on its wing coverts.

Diet and Feeding

Blue-footed Boobies primarily eat fish, such as sardines and anchovies, diving from great heights or swimming underwater to catch their prey. They hunt alone or in groups, often in the early morning or late afternoon.

Conservation status

The IUCN lists the Blue-footed Booby as Least Concern, but there has been a noted decline in populations, particularly in the Galápagos, potentially due to a decrease in sardine availability, a key food source.