Nazca Booby in Galápagos: Facts and Where to See It

A female Nazca booby often lays two eggs, but only one chick survives. This is called obligate siblicide: one chick grows larger and stronger, and the smaller one is pushed out of the nest and dies. The death is not always caused directly by its sibling; often the weaker chick simply cannot fend for itself once the parents leave the nest.

• Plunge-diver. Nazca boobies dive for fish from up to 30 metres, usually in the coastal waters around the islands. Females dive deeper and catch slightly larger fish.
• Bill colour. Males have yellow or orange bills, females paler, pinkish ones.
• Grey feet. The quickest way to tell them from the blue-footed and red-footed boobies.

Nazca boobies live along the eastern Pacific, from the coasts of South and Central America to Galápagos and Malpelo Island off Colombia, where they mainly breed. They are rarely seen far offshore. In Galápagos they are seen at sea between the islands and nest at colonies such as Punta Suárez and on Genovesa.

Guide sighting records list Nazca boobies at 8 sites. 3 are rated Likely: Punta Suárez on Española, and Darwin Bay and Prince Philip's Steps on Genovesa. Punta Pitt on San Cristóbal, Punta Vicente Roca on Isabela and the dive sites at Wolf and Darwin are rated Possible, and South Plaza Rare.

Nazca boobies fly around the islands all year. Nesting is the best time for a close view: on Genovesa from August to November, and on Española, where eggs are laid from November to February. In the next twelve months, 864 departures stop at a site where they are seen.

No, they are listed as Least Concern. Introduced predators and human development disturb them, and introduced pigs have caused colonies to be abandoned. Long-line fishing is a further threat. Park rules keep visitors on the trail and at least 2 metres (6 feet) from wildlife.

1. Mixing them up with masked boobies. The orange bill of the male and the grey feet are the clues.
2. Ignoring the nesting season. On Española it is November to February, on Genovesa August to November.
3. Stepping off the trail. Park rules keep visitors on marked trails at every visitor site.