Fish
Convict Tang
Acanthurus triostegus · also called convict surgeonfish, manini
Moving together in a large, coordinated school, a group of convict tangs sweeps across the reef grazing algae, their bold black-and-white stripes flashing in unison, a schooling habit that sets this species apart from most of its more solitary surgeonfish relatives.
Overview
The convict tang, Acanthurus triostegus, is native to ocean and coastal reef habitat across the Indo-Pacific region. Its bold striped pattern, unusual schooling behaviour among surgeonfish, and sharp defensive tail spine make it one of the more socially distinctive and visually recognisable tangs found on Indo-Pacific reefs.
Strength in numbers on the reef
While most surgeonfish defend algae patches alone or in pairs, the convict tang’s habit of gathering into large, coordinated schools gives it an advantage few other species in its family share, helping individuals feed more freely across contested reef territory.
Status
Least Concern, remaining widespread across suitable reef habitat throughout the Indo-Pacific region.
Convict Tang: common questions
Why is it called the convict tang?
It displays bold black vertical stripes across a pale body, a pattern resembling a prisoner's uniform that gives the species its common name.
Why does the convict tang school in large numbers?
Schooling in large groups may help the species overwhelm the territorial defences of other reef fish that would otherwise chase off individual algae grazers.
Where do young convict tangs live?
Juveniles are often found in shallow tide pools and lagoons before moving out to deeper reef habitat as they mature.
Where is the convict tang found?
It is native to ocean and coastal reef habitat across the Indo-Pacific region.