When you read something written by or listen to a coral reef ecologist, you often hear certain words thrown around that describe reef type or location; atoll, fore reef, patch reef and so on. But, what is always interesting, and sometimes confusing when working in another country are the local names for these reef structures. The Maldives is no exception. Flying and diving in the Maldives often provides the best opportunities to see these different reef structures.

The Maldives contains the world’s seventh largest reef system. The Archipelago is situated in the north central Indian Ocean, grouped by a double chain of 26 atolls positioned along an underwater ridge.  Even though the atolls encompass more than 1,190 coral islands spread over an area of 90,000 square kilometres, over 99% of the Maldives is underwater! This puts the Maldives in the world record books as one of the most disparate countries.


Examples of Maldivian Reef Names

Atoll: derived from the Dhivehi word atolhu and is a ring-shaped coral reef including a coral rim that encircles a lagoon partially or completely

Thila: an underwater pinnacle which is completely submerged

Giri: similar to a Thila but the top of these coral patches often extends near to the surface, or may even be exposed during low tides

Faru: a small atoll with reefs extending above the surface, often in a horseshoe shape


When we chose our permanent monitoring sites for the HARP Program in January, we wanted to ensure we represented all of these different reef structures and environments. This can help us understand how different environmental conditions affect the responses of corals to the unusually high water temperatures we are witnessing this year.


What's in a name?

Georgia Coward

a patch reef that is similar in structure to an atoll, with a central lagoon and outer rim of coral

the fore reef on the outside of north malé atoll

a coral island surrounded by a fringing reef

a thila we surveyed in baa atoll

The atolls of the Maldives