Nukutipipi atoll, Tuamotu archipelago; geomorphology, land and marine flora and fauna and interrelationships

Abstract

Nukutipipi atoll (5 km2), of volcanic origin 16-17 million years old on the Pitcairn (hot spot) Hereheretue line, presents a land flora and fauna of low diversity but with a Pisonia forest and hundreds of resident red-tailed tropic birds. Nukutipipi suffered from the 1983 hurricanes : destruction of vegetation and motu as well as sand lagoon mollusc populations. The north and south rims present original geomorphological structures. Lagoon without patch reefs reaching the surface is characterised by dome patch reefs all constituted of dead Acropora with few scleractinian and mollusc species, but an important algae coverage. All these characteristics indicate the precariousness on a time scale of such a so tiny atoll, land and marine, with a closed lagoon.