Identification
The grey triggerfish is a striking, laterally compressed fish of 30-45 cm (maximum 66 cm) with leathery, covered in tough, plate-like scales skin in grey to blue-grey. The mouth is small but contains powerful, chisel-shaped teeth for cracking shellfish and sea urchins. The first dorsal fin has three spines, the front one lockable like a trigger: only when the second spine is released does the first fold down. This defense mechanism gives the fish its name.
Ecology
Normally a resident of warm, subtropical waters around reefs and rocky bottoms in the Mediterranean and eastern Atlantic. Feeds on shellfish, crabs, and sea urchins.
Behaviour
The grey triggerfish is a bold, curious fish that shows little fear of divers. In summer the males excavate a nest on the seabed and defend it fiercely, chasing off intruders and lunging with their powerful teeth at anything that comes too close — divers and swimmers included. In the Mediterranean these nest-guarding bites occasionally prompt beach warnings. The infamous 'diver-attacking triggerfish' of tropical videos is usually the much larger titan triggerfish, but this species is anything but timid.
In the Netherlands
An irregular warm-water visitor appearing mainly during warm summers and autumns. Occasionally caught by anglers. Sightings are increasing, possibly due to North Sea warming.
