British Indian Ocean Territory (BIOT)*

The BIOT, also known as the Chagos archipelago is one of the world’s best preserved tropical island systems and the best preserved in the central Indian Ocean.

These islands provide sanctuary for a multitude of species of seabirds. The islands are home to 10 Important Bird Areas (IBA) recognized by BirdLife International, including Barton Point Reserve in Diego Garcia, which is home to one of the world’s largest populations of Red-footed Boobies (Sula sula).

The well-preserved beaches of the Chagos islands provide ideal nesting conditions for two species of marine turtles. The crystal clear waters of the archipelago host over 220 species of coral spread out over 25,000 km² of well-protected reefs, as well as several species of whales, dolphins and sharks. Read more


Lagoon in the Chagos Archipelago

Did you know?

The territory includes the Great Chagos Bank, the largest atoll in the world, and the Chagos Marine Protected Area (MPA), the largest no-take marine reserve in the world.


The Chagos MPA, declared in 2010, is to cover most of the British Indian Ocean Territory (BIOT) 200-mile zone, approximately 544,000 km².



* The Republic of Mauritius has initiated proceedings against the United Kingdom of Great Britain and Northern Island under the dispute settlement provisions of the 1982 United Nations Convention on the Law of the Sea (UNCLOS).

Status: Legal status under dispute*
Number of islands: 5 atolls, 55 islands
Population: indigenous inhabitants expelled in 1967-1973
Area: 54,400 km²
Population density: N/a
GDP/inhabitant: N/a
Unemployment rate: N/a
Economic activities: Military presence
Region: Indian Ocean