This large school contains Ringtail Surgeonfish (Acanthurus blochii) and Eyestripe Surgeonfish (Acanthurus dussumieri), both of which commonly feed on algae found on sand. Surgeonfish get their name from the sharp scalpels found at the base of the tail, which can be used to slash other fish both as an aggressive maneuver and in defense.

These fish were photographed in about 45 feet of water off the south Kohala Coast near Puako Beach on the Big Island of Hawaii.