Pew Environment Group
Global Ocean Legacy


Chagos Archipelago Marine Park

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The Chagos Archipelago and its surrounding waters is one of the most remote and unspoiled marine areas left on Earth

Located in the central Indian Ocean 1,000 miles south of India, the isolated Chagos Archipelago is a chain of more than 50 islands and vast coral reefs surrounded by some of the world's purest seas.

This “Galapagos of the Indian Ocean” is home to the world's largest coral atoll with a remarkable diversity of 220 coral species and 1,000 species of fish. It serves as a refuge and breeding ground for large, critically important populations of sharks and dolphins, as well as green and hawkbill sea turtles. This atoll also provides habitat for the richest diversity of seabirds in the Indian Ocean and the world's largest land arthropod, the coconut crab.

The exceptionally healthy reefs of the Chagos Islands are considered among the most resilient to warming temperatures, providing an invaluable scientific benchmark against which to measure other impacted corals. Although Chagos reefs suffered heavy mortality in 1998 from spikes in water temperatures, research in 2006 revealed that they made a vigorous recovery, unusual for Indian Ocean reef systems which elsewhere were more seriously affected.

The Archipelago also plays a vital role in the health of the Indian Ocean, generating an abundance of larvae and juvenile marine life that spread elsewhere and sustain marine populations throughout the region.

The Chagos, an overseas territory of the United Kingdom, represents over two-thirds of the coral reefs under the British flag and are by far its greatest area of marine biodiversity. Except for a military base, the islands are uninhabited and largely undeveloped.

The deep oceanic waters around the Chagos Islands out to the 200 mile nautical limit include an exceptional diversity of undersea geological features including fracture zones, sea-floor spreading, submarine mountains, mid-ocean ridges, trenches deeper than 6,000 meters (18,000 feet), and a broad abyssal plain. The Chagos are believed to be one of the most geologically active areas in the world not part of a continental plate. Although these deepwater habitats surrounding the Archipelago have not been explored or mapped in any detail, work elsewhere in the world has shown that high physical diversity of the sea floor is closely linked to a high diversity of species. Further research using deep sea submersibles and other new technologies will likely demonstrate a significant degree of variability in the abundance and richness of sea life found here.

The Chagos represent an unparalleled opportunity to set aside one of the world's premier ecosystems as a highly protected marine park amid the nations of the Indian Ocean whose shores are densely populated and industrialized and whose waters are increasingly over-exploited and degraded.

The Chagos campaign is part of Global Ocean Legacy, a collaboration of the Pew Environment Group, the Oak Foundation, The Robertson Foundation, and the Sandler Family Supporting Foundation to protect some of the world's largest and most spectacular marine habitats.

The Chagos Environment Network

The Chagos Environment Network (CEN) is a partnership of NGOs and institutions who are working together to protect the Chagos and its surrounding waters.

Latest News

Proposed Indian Ocean Chagos marine reserve sparks controversy - USA Today - March 9, 2010

UK Poised to Designate World's Largest Marine Reserve - Pew Environment Group - 5 March 2010

Troubled history tinges marine plan - BBC - March 2, 2010

An Olympic-style challenge: U.K. vs. U.S. for ocean champion - Discovery News - February 23, 2010

The Case for the Chagos Protected Area (PDF) - Chagos Environment Network - January 29, 2010

The Chagos Protected Area: A Unique Scientific and Conservation Opportunity for the UK (PDF) - Chagos Environment Network - January 25, 2010

Chagos Environment Network launches new website to protect the Chagos Islands - 23 December 2009

Chagos Environment Network Welcomes the UK Government's Public Consultation on Protecting the Marine Biodiversity of the Chagos Islands - Chagos Environment Network - 10 November 2009

REPORT: Marine conservation in the British Indian Ocean Territory (PDF) - Scientific workshop makes very convincing case for designating all the waters around the Chagos as a protected area

UK's Chagos Archipelago is comparable to the Galapagos Islands or the Great Barrier Reef - Wildlife Extra News - March 2009

Call for UK to create world-class marine park - The Royal Society for the Protection of Birds - 10 March 2009

Conservation Plea on Ocean Islands - Daily Express - 10 March 2009

Call for UK to create world-class marine park - Surfbirds News (USA) - 10 March 2009

Conservation plans for Chagos unveiled - ProtectPlanetOcean.org - 9 March 2009

Keeping Chagos Atoll 'Pristine' Complicated by US Bomber Base - Bloomberg - 9 March 2009

Giant marine park plan for Chagos - The Independent (UK) - 9 February 2009

Ocean Blues - The Economist - 9 February 2009