Black Triggerfish (Melichthys niger)

This fish makes his home around the world from the western Atlantic down to Brazil, the Pacific from San Diego down to Columbia and even South Africa.

These fish usually inhabit seaward reefs and oceanic islands.  Their diet consists primarily of algae and zooplankton.  They have also been seen congregating around spinner dolphins and eating the small pieces of debris left as the dolphins consume various crustaceans. 

They use their dorsal and anal fin to swim at slower speeds, waving these fins back and forth in an undulating motion, which appears very fluid and smooth.  For higher speeds they use their tail fin for propulsion.

Being a member of the trigger family, they have a spine on their dorsal surface which can be laid down flat against their body or lifted to stand up.  They use this spine for protection and will turn it toward their predator if they are threatened.  They will also use it when sleeping by wedging themselves into a coral niche and putting up the spine so nothing can pull them out.