Description

Also known as Black Durgon, Black Durgon Triggerfish, Black Oldwife, Blackfish, Ebony Triggerfish, Hawaiian Black Trigger, Hawaiian Black Triggerfish, Negro Trigger.

Found singly or in loose schools, over outer reef crests, drop-offs, and slopes, of clear seaward reefs, around oceanic islands.
They feed on algae and zooplankton, sometimes high above the reef.
Length - 35cm
Depth - 2-70m
Widespread Circumtropical

Indian Triggerfish dig their shelters under solid objects by swimming sand away. This is done by putting their mouth against a solid object and swim like crazy, thereby creating a current that takes the sand away and making a little nest area.

Triggerfish have a hard spine Dorsal Fin that can be locked.
When sleeping this spine is used to wedge them into place in a crevasse and so deter predators from pulling them out of their bed!
The spine is also held erect as a warning to other fish to stay away.
Several large Titans blow shallow depressions in the sand for nesting and if approached will raise this spine as a warning, if ignored they may charge, even divers! especially the Titan Triggerfish who will take a tasty bite!! Beware!!! (edit) Ref: https://www.fishbase.se/summary/966