The variety of species living on a coral reef is greater than in any other shallow-water marine ecosystem, making reefs one of the most diverse ecosystems on the planet

Covering less than one percent of the ocean floor, coral reefs support an estimated 25 percent of all known marine species. And the variety of species living on coral reefs is greater than almost anywhere else in the world. Scientists estimate that more than one million species of plants and animals are associated with coral reef ecosystems.
With its extensive reef tract, Florida Keys National Marine Sanctuary protects more than 50 species of coral, including the federally protected Staghorn and Elkhorn corals. The sanctuary is also home to more than 500 species of fish and countless other types of marine life.
The biodiversity of reefs and the habitat reefs provide for other species are also the source of other benefits. For example, reef-based fisheries provide food and income, reef-based recreation like diving and snorkeling provide income for local economies and leisure to millions, and compounds isolated from organisms living on reefs hold vast medical potential.