Pascal Kobeh / Close-up of the head of a Yellowfin surgeonfish (Acanthurus xanthopterus) Maldives, Indian Ocean.

Juergen Freund / Yellowfin surgeonfish (Acanthurus xanthopterus), Great Barrier Reef, Queensland, Australia.

Claudio Contreras / Yellowfin surgeonfish (Acanthurus xanthopterus) with Leopard grouper (Mycteroperca rosacea) in the background, Cabo Pulmo National Park, Sea of Cortez (Gulf of California), Mexico, July

Georgette Douwma / Yellowfin surgeonfish (Acanthurus xanthopterus) feeding on a dead surgeonfish. Many fish observed dead or dying on reefs in the Maldives, April 2012. Another episode of dying fish occured in 2007. Cau...

Fred Bavendam / Yellowfin Surgeonfish (Acanthurus xanthopterus), Bali, Indonesia

Pete Oxford / Yellowfin surgeonfish (Acanthurus xanthopterus valenciennes) Española / Hood Island, Galapagos

Jeff Rotman / Close-up of eye of Yellowfin surgeonfish {Acanthurus xanthopterus} Great Barrier Reef, Australia

Jeff Rotman / Yellowfin surgeonfish portrait {Acanthurus xanthopterus} Great Barrier Reef, Australia

Noemie Stroh / Yellowfin surgeonfish (Acanthurus xanthopterus) aggregation above coral reef. Grey reef shark (Carcharhinus amblyrhynchos) juveniles are patrolling the school. Ohotu reef, North Fakarava, French polyn...

Noemie Stroh / Yellowfin surgeonfish (Acanthurus xanthopterus) aggregation above coral reef. Grey reef shark (Carcharhinus amblyrhynchos) juveniles are patrolling the school. Ohotu reef, North Fakarava, French polyn...

David Fleetham / Yellowfin surgeonfish (Acanthurus xanthopterus) female at a cleaning station with endemic Hawaiian cleaner wrasse (Labroides phthirophagus) Hawaii.