Titan Triggerfish Adult

Titan Triggerfish Adult (Balistoides viridescens)

The titan triggerfish, also known as the giant triggerfish or moustache triggerfish, is a large species found in lagoons and reefs throughout the Indo-Pacific, reaching depths of up to 50 meters (160 feet). Notably, it is absent from Hawaiian waters. This species can grow up to 75 centimeters (30 inches) long, making it one of the largest triggerfish, although the stone triggerfish from the eastern Pacific is larger.

The titan triggerfish is a diurnal and solitary creature, primarily feeding on sea urchins, mollusks, crustaceans, tube worms, and coral. It forages by flipping over rocks, stirring up sand, and biting off pieces of branching coral. This feeding behavior attracts smaller fish, which benefit from the detritus and smaller organisms it uncovers. The titan triggerfish is also known to hunt and consume crown-of-thorns starfish.

These fish can exhibit aggressive behavior toward others that enter their territory.

While titan triggerfish are generally cautious around divers and snorkelers, females can become territorial and aggressive during the breeding season, which occurs for about a week each month, either after the full moon or new moon.

Their nests are typically placed in flat sandy areas and are vigorously defended against intruders. The territory surrounding the nest has a cone shape, and divers who inadvertently enter it may face aggressive behavior. It is advised for divers to swim horizontally away from the nest rather than upwards, which could lead them deeper into the territory. Although their bites are not venomous, the titan triggerfish has strong teeth that can cause significant injury requiring medical attention.