Frequently Asked Questions
Why are they called parrotfishes?
Teeth of a parrotfish photographed at a depth of 12 m, Ribbon Reef #3, Great Barrier Reef off Cooktown, Queensland, December 2001. Note the crustacean (probably a copepod) on the fish's upper lip. Photo © E. Schlögl. View larger image.
Teeth of a Bullethead Parrotfish. The fish was photographed at a depth of 6 m, 'Steve's Bommie', Ribbon Reef #3, Great Barrier Reef off Cooktown, December 2001. Photo © E. Schlögl. View larger image.
A Double-headed Parrotfish at Sipadan, Malaysia. The beak-like teeth are clearly visible. Photo © G. McNeil. View larger image.
The name 'parrotfish' refers to the teeth, which are fused into a parrot-like beak.
Parrotfish expert Dr David Bellwood from James Cook University, stated that "The teeth of parrotfishes are constantly replaced. Those on the biting edges are relatively small and as they wear, are replaced by new teeth that are developing within the ‘beak’. Most of the visible ‘beak’ is cement on the outside of the jaw. The erupted teeth are only on the cutting edge. Depending upon the type of parrotfish, the teeth appear to develop in vertical rows (scraping Scarus species) or oblique rows (excavating species such as Chlorurus, Sparisoma and Bolbometopon)."
Parrotfishes are nearly all herbivores that occur on coral reefs. They feed by grazing algae off coral. They are not selective, but graze turf and calcareous algae, along with the calcareous coral upon which it grows.
In addition to jaw teeth, parrotfishes have specialised pharyngeal teeth in the "throat" which grind food. This results in the algal cell walls being broken, releasing the contents for digestion. It also reduces the coral to a paste.
Parrotfish feeding is responsible for the removal of significant amounts of coral. A large Double-headed Parrotfish (bottom image) is believed to remove about one cubic metre of coral annually.
For many years, parrotfishes were classified in the family Scaridae. Most recent work, however, indicates that the parrotfishes constitute a subfamily of the wrasse family Labridae.
Further reading
- Choat, J.H. & D.R. Bellwood. in Paxton, J.R. & W.N. Eschmeyer (Eds). 1994. Encyclopedia of Fishes. Sydney: New South Wales University Press; San Diego: Academic Press. Pp. 240.
- Helfman, G.S., Collette, B.B. & D.E. Facey. 1997. The Diversity of Fishes. Blackwell Science. Pp. 528.
- Westneat, M.W. & M.E. Alfaro. 2005. Phylogenetic relationships and evolutionary history of the reef fish family Labridae. Molecular Phylogenetics and Evolution. 36 (2): 370-390.
