Coral reefs are essential spawning, nursery, breeding, and feeding grounds for numerous organisms. In terms of biodiversity, the variety of species living on a coral reef is greater than in any other shallow-water marine ecosystems and is one of the most diverse on the planet, yet coral reefs cover less than one tenth of one percent of the ocean floor. [a] Of the 34 recognised animal Phyla, 32 are found on coral reefs, compared to only nine Phyla in tropical rainforests. [b] In addition to scores of invertebrate species and macrofauna (sharks, sea turtles, etc.), coral reefs support more than 800 hard coral species and more than 4,000 species of fish. [a, c] Over 25 percent of the world's fish biodiversity, and between nine and 12 percent of the world's total fisheries, are associated with coral reefs. [a] While a portion of these diverse species are associated with reefs only to hunt or for a portion of their life cycle—such as juveniles utilizing reefs as a nursery and adults during spawning—others spend their entire lives in reef ecosystems. And this may only be the tip of the iceberg; scientists estimate that there may be another one to nine million undiscovered species of organisms living in and around reefs! [d]
By one estimate, biodiversity value accounts for $5.5 billion of the total estimated annual global net benefit of coral reefs. [e] In Hawai`i alone, a study placed annual value of biodiversity on Hawaiian reefs to be $17.84 million/year. [f] The Coral Triangle is located along the equator where the western portion of the Pacific Ocean meets the Indian Ocean; it includes all or part of the exclusive economic zones of Indonesia, Malaysia, Papua New Guinea, the Philippines, the Solomon Islands, and Timor-Leste. This region is recognized as the most biodiverse reef region in the world—it is home to one third of the world's remaining reefs, 75 percent of the known coral species, and almost 3,000 species of fish—the total value of that region's coral reef ecosystems is estimated at $2.3 billion/year. [g]
While less well studied than shallow-water reefs, deep-sea coral communities are thought to support the greatest biodiversity in the deep ocean. At several sites in the northeast Atlantic, 92 percent of fish species were associated with communities of Lophelia deep-sea corals rather than the surrounding seabed. Several deep-sea communities have already been identified as essential habitat for federally-managed species. [h]
The values coral ecosystems provide in terms of biodiversity and habitat for other species feed into benefits for humans, such as fisheries that provide food and income for millions, reef-based recreation like diving and fishing that provide income for local economies and leisure to millions, and the medical potential of compounds isolated from organisms living on reefs.
*Unless otherwise noted, all monetary values presented are in US Dollars.