The Nazca Booby (Sula granti) is a booby bird found in the eastern Pacific Ocean, namely on the Galápagos Islands where eco-tourists can see it, and on Clipperton Island. It was first described by Walter Rothschild in 1902 and was long considered a subspecies of the masked booby until it was recognized genetically and behaviorally distinct in 2002. It was historically known to be a subspecies of the Masked Booby, but now the Nazca Booby is recognized as a distinct species. On Clipperton Island, the Nazca Booby co-occurs with the Masked Booby, where they can seldom hybridize. The female bird is smaller than the male bird. It has a mostly white body, but the top of its tail and its wings are colored a dark brown to black color. The bird incorporates a black mask over its eyes, which makes it quite distinctive. The bill is typically a bright orange color for males and an orange-pink colorize females. Nazca Booby Birds are the biggest of all the boobie birds on the Galapagos Islands. Nazca Booby birds are ground-nesting and annual breeders, but they have been behaving as opportunistic breeders in the last few years. Nazca boobies demonstrate a fascinating dance routine during courtship, which starts with the point of the sky. Male Nazcas perform this display to signal to prospective females that they are available to mate. The species occurs within the eastern Pacific from the islands in Lower California to the island and also the Isla de estuary in Ecuador and Malpelo in Colombia.
The booby Nazca makes its nest near the cliff, sometimes on rocky ledges. It likes to nest in barren patches of soil, where there is no vegetation cover. Nazca Booby Birds lay two eggs, several days apart from which, due to a procedure called ‘obligatory sibling killing,’ only one chick survives. In this process, one of the chicks displaces the other by taking most of the food and thus growing more quickly. The bigger chick kicks the smallest and weakest chick out of the nest until that has been done, leaving it to die of thirst or cold. On small fish captured by diving at high speed from flight into the ocean, the Nazca booby preys. The main food species is South American pilchard, but also take teleostan, anchovies, and squid, especially during the El Niño events, when sardine numbers are low. Due to their sexual dimorphism, females tend to go after bigger prey and dive deeper. The Galapagos Islands have numerous locations where the Nazca booby can be seen. Genovesa Island and Espanola Island are frequently seen there. Also, present on Floreana Island is the Nazca booby. That means it can be seen on some cruises on the Galapagos Islands, and on some land-based trips on Galapagos. The Nazca booby is classed as Least Concern by the IUCN. Although populations are thought to decrease to some extent, this decline isn’t strong enough to want classification in an exceedingly threat category.