Clown Triggerfish

Photo: Luis P. B. · CC BY-NC

Clown triggerfish are among the most visually distinctive reef residents at An Thoi, their bold white-spotted black body, bright yellow mouth patch, and white facial markings making them unmistakable as they survey their territorial patch of reef for intruders. They use their powerful jaws and trigger-locking dorsal spine — which locks them into reef crevices when threatened — as dual defense mechanisms, and are known to charge divers who approach nest sites. Their diet of hard-shelled invertebrates makes them important regulators of urchin and mollusk populations on the reef flat.