Current scholarly estimates put the number of species whose sustenance and propagation depends on coral reefs at a minimum of 30,000, including more than 3000 fish species alone. For this reason the reefs have been called "the rainforests of the ocean." They comprise the world's most complex and abundant ecosystem.
有「海中熱帶雨林」之稱的珊瑚礁，目前已知至少有 3 萬種生物仰賴其繁衍後代，光是珊瑚礁魚類就有 3,000 種以上，是世界上最複雜也最豐富的生態系。