All the archipelagos of French Polynesia, except for the Marquesas, have almost exclusively coral marine coastal ecosystems. Although their richness in reef species is lower than further west, a mere square mile of coral reef contains a number of species equivalent to that of the entire coastal marine area of ​​metropolitan France. 200 species of corals, 1200 of fish, 1000 of crustaceans and 2500 of molluscs have been identified.