Triggerfish

Triggerfish are oval, armour-scaled reef fish with a strong, shell-crushing bite. In this app the group includes the Titan triggerfish, Picasso triggerfish, and Clown triggerfish.

Triggerfish get their name from a locking spine on the back: the first spine stands up and locks in place until a second, smaller "trigger" spine is pressed down. Colour pattern and body shape are the easiest ways to tell the different species apart.

Triggerfish have a flat, oval body covered in tough, rough scales that act like armour. The head is large with small eyes set high and back, and a small, strong mouth built for crushing shells. The tail fin is sickle-shaped for fast bursts of swimming.

Triggerfish are found on reefs, often over sandy sea bottoms or rocky ground where they set up territories.

Triggerfish are intelligent for fish and can learn from experience. Males guard a territory that holds one or more females, and some species, such as the Picasso and titan triggerfish, will aggressively chase off intruders, including divers, near their nest.

Triggerfish mostly eat slow-moving, shelled animals such as crabs, molluscs, and sea urchins. Some also eat small fish or algae, and a few feed mainly on plankton.

Triggerfish lay their eggs on sandy ground within a male's territory, often timed to the phase of the moon and the tides. A male may mate with several females in his territory, and pairs prepare the egg site by blowing water onto the sand.

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  Black Triggerfish

  Melichthys niger

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  Boomerang triggerfish

  Sufflamen bursa

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  Clown triggerfish

  Balistoides conspicillum

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  Grey triggerfish

  Balistes capriscus

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  Orange-lined triggerfish

  Balistapus undulatus

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  Picasso Triggerfish

  Rhinecanthus aculeatus