The Orange-Band Surgeonfish is characterized by a distinct orange band running vertically through its pectoral fins. Adults have a dark brown to olive body color, with a pale yellow to white area below the orange band. Juveniles are bright yellow. The body is laterally compressed, with a sharp, forward-pointing spine on the caudal peduncle used for defense. They can grow up to 35 cm (about 14 inches) in length.
The species is widespread in the Indo-Pacific region. It ranges from the eastern coast of Africa, including the Red Sea, to the central Pacific Ocean. Commonly found in the Hawaiian Islands, Japan, the Philippines, and the Great Barrier Reef.
Acanthurus olivaceus typically inhabits reef flats, lagoons, and outer reef slopes. They are found at depths ranging from 1 to 50 meters but are most commonly observed at depths of 5 to 25 meters. They prefer areas with abundant algae growth, which is their primary food source.
The Orange-Band Surgeonfish primarily feeds on benthic algae. They use their small, sharp teeth to graze on algae growing on rocks and coral. They may also consume small invertebrates and detritus.
Breeding behavior in Acanthurus olivaceus includes the formation of pairs or small groups. Spawning typically occurs during the evening, synchronized with lunar cycles to maximize the dispersal of eggs and larvae. Females release their eggs into the water column, where males fertilize them externally.
While not currently listed as endangered, the Orange-Band Surgeonfish faces threats from habitat destruction, overfishing, and climate change. Conservation efforts focus on protecting coral reef habitats and regulating fishing practices to ensure sustainable populations.