A large eastern Pacific parrotfish with a steep forehead, grazing rock in groups and audible while doing it.
To 80 cm. Adults are green to bluish-green with dark blue fins and a dark blue beak, and dark spoke-like lines radiating from the eye, which is the best mark. Large fish develop a prominent forehead hump. Juveniles are tan with a yellowish tail base and fins, blue radiating lines and blue fin edges.
The azure parrotfish is the confusion and has only a slight hump and orange-brown scale outlines instead of the dark beak and dark eye spokes.
A note on the name. This site calls it the eastern Pacific bumphead parrotfish because a plain “Pacific bumphead” is ambiguous: the green humphead parrotfish of the Indo-West Pacific is also a Pacific fish, is much larger at 130 cm and 46 kg, and is listed as vulnerable, where this one is not. Adding “eastern” fixes it, because the green humphead does not occur in the eastern Pacific at all. FishBase and the Smithsonian both call this fish simply the bumphead parrotfish.
It grazes rocky reef in small groups between 1 and 30 m. It is endemic to the tropical eastern Pacific and is recorded from Baja California to northern Peru and at Revillagigedo, the Galapagos, Cocos and Malpelo.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.