Nazca Booby

The Nazca booby (Sula granti) is a large colonial seabird of the eastern tropical Pacific. Major breeding colonies occur in the Galápagos Islands and on islands off Ecuador, Colombia, and Mexico. Adults have predominantly white plumage, black flight feathers and tail, a dark facial mask, gray feet, and an orange-to-pink bill. Females are generally larger than males and often have paler bills.

Nazca boobies breed on open, sparsely vegetated ground, frequently near cliffs. A pair lays one or two eggs in a shallow scrape surrounded by small stones or other loose material. Both parents incubate the eggs using the warm, highly vascularized skin of their webbed feet rather than a conventional brood patch.

When two chicks hatch, the older chick usually forces the younger from the nest, and only one chick is normally raised. The second egg therefore functions primarily as insurance if the first egg fails to hatch.

Nazca boobies feed mainly on fish and squid captured by plunge-diving from the air. Their reproductive success can change substantially with ocean conditions, particularly during El Niño events that alter the availability of preferred prey. The species is currently classified globally as Least Concern, although some colonies face pressures from changes in food supply, fishing activity, pollution, introduced predators, and disturbance.