The Site is a low-lying island of coral origin in the Mozambique Channel with a central lagoon enclosed by mangroves. The island itself is surrounded by a “fringing reef”, interrupted by sandy beaches, which constitute one of the world's most important breeding and nesting sites for the globally endangered green sea turtle Chelonia mydas. The Site offers habitat to the globally endangered Madagascar pond heron (Ardeola idae), the vulnerable fin whale (Balaenoptera physalus) and the critically endangered great hammerhead shark (Sphyrna mokarran). It supports a high number of nesting sea birds including two subspecies endemic to the Indian Ocean: Audubon’s shearwater (Puffinus lherminieri) and sooty tern (Onychoprion fuscatus). Other animals found on the island include endemic nesting birds such as the Madagascar white-eye (Zosterops maderaspatanus), four species of reptiles of which two are endemic, and 103 arthropods with more than 20 endemic. The coastal waters host seven species of sea mammals, 390 fish, 141 cnidarians and 176 shellfish. More than 1,250 plant and animal species have been recorded in total. The mangrove and seagrass beds protect and stabilize the coastline, reducing erosion. 14 soldiers of the French Armed Forces in the Southern Indian Ocean Zone permanently occupy the island. Otherwise the only threatening factors relate to introduced species such as goats and plants such as the green choca. Nonetheless, the state of conservation of the island is probably extremely close to its original state. The Site serves as a laboratory for the study of the natural evolution of island ecosystems and global change, and more research is encouraged.