The triggerfish family, any of some 30 species of shallow-water marine fishes of the family Balistidae found worldwide in tropical seas is characterized by fairly deep-bodied and usually colourful fishes with large scales, small mouths, and high-set eyes. Their common name refers to the triggering mechanism in the first two of their three dorsal fin spines. The first spine can be erected by the fish and locked in place by the second, the trigger, which must be withdrawn before the first spine is released. The first spine is large and strong and, when locked upright, can hold the fish tightly in protective crevices.
The back of the body narrows sharply, ending in a long, high caudal fin, tapered in its upper and lower parts. The gray or common triggerfish (triggerfish capriscus) is spotted gray-brown, with three dark vertical bars more or less marked. The upper half of the body and the fins are marked with blue reflections.
Triggerfishes are found among reefs and marine plants. Although generally considered edible, some cause food poisoning. The largest triggerfishes grow about 60 cm (2 feet) long. Common species include the queen triggerfish (Balistes vetula), a tropical Atlantic fish brightly striped with blue, and Rhinecanthus aculeatus, a grayish, Indo-Pacific fish patterned with bands of blue, black, orange, and white.
Zoophage or carnivore, its powerful teeth arranged in two rows with the upper jaw are capable of breaking the coral and the shells of molluscs including that of oysters. It swallows the living coral polyps and spits out the debris from the calcareous skeleton in the form of fairly coarse white sand.
The grey triggerfish can be approached by divers, but it remains fearful (bubbles?). It seems that he is less fierce towards freedivers. But beware during the breeding period, it defends the nest by biting !!
At its juvenile stage, the gray triggerfish is often very dark in color, but becomes more or less light gray at its adult stage and the 3 black sidebars disappear almost completely. Also on the video above (shot off the west coast of Florida around a shallow wreck in turbid waters), you can notice white parasitic worms on its outer skin between the opercula and the pectoral fins. In addition, you can clearly see his way of eating as explained above.
Shot around a shallow reef, again off the west coast of Florida, the video above highlights how the grey triggerfish, here seen as a couple, sets up, retracts or locks its first dorsal spine. Given its size and its colors, this is the gray triggerfish at its adult stage. One can clearly notice the blue reflections indicated above.
