Marine Life Protectors

Tropical Coral Reefs

Views from above the surface:

Fringing reef in Wakatobi National Park, Indonesia
Credit: Photo 73865014 © Ethan Daniels |
     Atoll islands and reefs in the Maldives
Credit:Photo 15029992 / Maldives © Steve Allen |

Underwater views:

Indo-Pacific: Wakatobi, Indonesia, Coral Triangle, 2018      Caribbean: Little Bonaire, 2015

Tropical coral reefs can look quite different, depending on the region where they occur. They are built by tiny animals, the coral polyps.
A lot of coral polyp species live in colonies, although there are also solitary coral which only consist of a single polyp. Regarding biological taxonomy, coral belong to the class of Anthozoa within the phylum Cnidaria.
The most important reef builders are hard coral from the subclass Hexacorallia. Hexacorallia polyps produce a skeleton of calcium carbonate (coral limestone). From generation to generation they build up a bigger structure, the skeleton of the whole coral colony. Branching hexacoral from the genus Acropora are especially fast growing coral, their branches can grow up to 10 cm per year, while Porites coral are an example for slow growing coral, they produce only some millimetres of new coral skeleton per year.

Acropora table coral, Wakatobi NP, Indonesia, 2018      Porites coral, Kaafu Atoll, Maldives, 2017

Further content not available. Withdrawn on Oct 20, 2021. Section will be updated later.