Fauna
Species

Convict Tang

Acanthurus triostegus

Also known as Manini, Convict Surgeonfish, Convict Surgeon, Fiveband Surgeonfish

Convict tangs are highly social surgeonfish easily recognized by their creamy-yellow bodies marked with six vertical black bars resembling a prison uniform. They graze in large, coordinated schools that overwhelm the territorial defenses of damselfish to feed on benthic algae. These schools play a vital role in coral reef health by preventing algae from smothering the living coral.

Reef-dwellingSchoolingAlgae-eater
Convict Tang reference1 / 7
brian.gratwicke / CC BY 2.0 · cc-by
—observations
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Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preyFilamentous algae, Blue-green algae, Diatoms
Predators
  • Groupers
  • Moray eels
  • Snappers
ThreatsHabitat degradation, coral bleaching, and overfishing for the aquarium trade
HabitatsShallow coral reefs, rocky shores, tide pools, and lagoons
Life span5 to 7 years
Classification
  1. FamilyAcanthuridae
  2. SpeciesAcanthurus triostegus
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Equipped with sharp, blade-like spines on the tail base; handle with extreme care if caught.
Why it is dangerous
Possesses modified, razor-sharp scales called caudal spines on either side of the tail base that can inflict deep, painful cuts if the fish thrashes.
How to recognize a risky encounter
Look for the six vertical black stripes on a pale yellow body and a small, sharp spine tucked near the tail base.
What to do
Never grab a live fish by the tail; use a soft net or thick gloves if handling is necessary.
Responsible observation
  • Observe schooling behavior: Look for large groups moving in unison over shallow reef flats during high tide.
  • Keep your distance: Avoid cornering them against rocks, as they may use their sharp tail spines defensively.
  • Watch the substrate: Notice how they scrape algae off rocks, leaving clean patches behind.
Related species
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