Cleaner Fish - Underwater Capitalism

Another great aspect of diving is watching the many different behaviors of reef species in their natural environment.  There is foraging by vegetarian fish, hunting, schooling, camouflage, and many others.  One of the most fascinating fish behaviors is cleaning behavior.

Here are pictures from a cleaning station on Osprey Reef with a Malabar Grouper being cleaned by a Bluestreak Cleaner Wrasse.

The client fish stays very calm with his fins, gills, and even his mouth open.  The cleaner fish then inspects the client, especially the gills and mouth for parasites.  The client fish almost seems to go into a trance, it must be like a massage!  For divers, cleaner stations are excellent because the fish often allow divers to get closer than normal.

Dr. Alexandra Grutter with the Coral Reef Ecology Laboratory at the University of Queensland has discovered some fascinating aspects of cleaner fish behavior.

Cleaner fish, or shrimp, pick parasites and dead cells off other fish.  These fish have a distinctive ultraviolet blue color and use specific swimming behavior to advertise their cleaning stations.  These cleaning stations are very busy.  One cleaner fish inspected 2300 "clients" from 130 species, eating 1200 parasites, all in one day.

Cleaning stations are also very competitive.  Dr. Grutter's research has shown that better service with less harmful biting of the client fish had greater repeat visits from clients.  The free market at work underwater!