Marine Wildlife Encyclopedia
Titan Triggerfish Balistoides viridescens
The titan triggerfish is also known as the mustache triggerfish due to a dark line above its lips. It has large, strong front teeth and strong spines in its first dorsal fin. The first and longer spine can be locked in an upright position and released by depressing the second smaller “trigger” spine. This allows the fish to jam itself into a reef crevice, where it can rest safely, away from potential predators. The titan triggerfish preys on shellfish and crustaceans, which it crunches up using its tough mouth and teeth. It can even make a meal of sea urchins by flipping them over and biting them on their vulnerable underside, where the spines are shorter.
In the breeding season, titan triggerfish dig a nest in a sandy patch of coral rubble using their mouth as a water jet. The female lays her eggs in the nest and one or both of the parents remains nearby to guard it. Normally a wary fish, parent titan triggerfish will attack divers that come too close to the nest and can inflict severe bites that need medical attention.