The Cargados Carajos are closely skirted by busy Southeast Asian shipping lanes (North and South of the Archipelago) making its unique ecosystem extremely vulnerable to a variety of risks which pose threats to its long-term existence as a Key Biodiversity Area.
It is a vital habitat for endangered marine and terrestrial species and faces an existential threat from shipwrecks, illegal fishing and pollution.
St. Brandon has more than 200 km2 of reef habitat and possesses possibly one of the most biodiverse ecosystems on earth holding over 25% of known marine species when these cover less than 1% of the sea floor.
In the West, there is a coral bank and a fringing reef, dominated by staghorn Acropora, classified as threatened by the US National Marine Fisheries Service in 2014.
There are persistent, but as yet unproven rumours, of the presence of rare brain corals around Avocaré Island in St. Brandon waiting to be discovered and preserved for posterity.