Hawaiian Coral Reefs

Hawaiian coral reefs provide important habitats for fish, invertebrates, monk seals, green sea turtles, and thousands of other species of animals and plants. There are more than 150 different coral species in Hawaiian waters (25% are endemic to the Hawaiian Islands). The most common corals are lobe corals, rice coral, blue coral, and cauliflower coral, found in active shallow waters. Delicate, branching corals such as sea fan, shelf, and finger coral are the most common Hawaiian corals growing in calmer, deeper waters.

Coral species in Hawaiian waters help support many of the 860 native algae species, which include more than 80 endemic algae. There are also more than 1,140 fish native to the Hawaiian Islands, including 149 endemic fish. Coral reefs around the Hawaiian Islands also help support native invertebrate species, such as crabs, sea urchins, and shrimp. More than 9,270 native Hawaiian invertebrates have been documented, including more than 7,230 endemic species.

Growing less than one inch per year, coral reefs can take hundreds of years to form. Many Hawaiian corals spawn, or rejuvenate, just once or twice a year. Rice coral spawns in June and July two days after a full moon between 8 and 10 pm. Mushroom coral spawns one to four days after a full moon between 5 and 7 am between the months of June and September.

Coral reefs are living communities that provide shelter, food, and living space for an incredible diversity of species. Among the great variety of organisms on Hawaii’s reefs are species that hold potential for natural medicines, like a chemical found in Hawaiian sponges that has recently shown promise in fighting tumors and malaria. Medical researchers have also found that ground-up coral is accepted by the human body and works well for bone grafts. And many corals have evolved unique compounds that naturally shield them against UV radiation, providing researchers with insights into improving sunscreens.