The Nazca Booby (Sula dactylatra granti, piquero de Nazca), formerly known as the masked booby, is alabaster white with a black tail and black ends to the primary feathers on the wing. Some black skin at the base of the bill serves as an unequivocal Zorro-mask (hence the original name). The Nazca booby is also the largest of the three booby species in the Galapagos.

As with other boobies, the Nazca booby feeds entirely on fish and follows the same courtship ritual, although a bit less elaborate. Males and females look alike, so the best way to distinguish them is by their sounds: the males whistle and females quack.

Nazca boobies are commonly seen at Punta Suarez (Española), Punta Pitt (San Cristóbal), Daphne Major, and Genovesa.