Chagos Archipelago

The British Indian Ocean Territory (BIOT) is one of the UK’s 14 Overseas Territories and one of the most amazing marine environments anywhere in the world. Located about 1,500km from the southern tip of India, 3,400km due east of Africa and 3,000km west of Indonesia the territory covers a total of 640,000km2 of ocean. At its heart is the Chagos archipelago, a scattering of 55 tiny islands surrounded by 60,000km2 of coral reefs and the cleanest seawater ever recorded. ZSL has been actively working in BIOT for more than 10 years and our efforts there are collaborative across our departments and with many other institutions globally.

Why we are there

The open ocean, tropical coral reefs and islands of the territory have a huge abundance of marine and terrestrial species. BIOT contains the largest living coral atoll anywhere on earth – the Great Chagos Bank, one of the few increasing breeding seabird colonies in the tropical Indian Ocean and eight times more reef fish biomass than anywhere else in the Indian Ocean [1].

BIOT teems with life, from large pelagic predators like thresher sharks, yellowfin tuna, huge pods of spinner dolphins, to abundant reef fish and seabirds. Whilst under pressure from threats such as climate change and illegal fishing, due to the remote location, exploitation of the reefs and pelagic wildlife is reduced and hence the abundance of wildlife found in BIOT still represents some of the best examples of these habitats left anywhere in the world.

The largest no-take Marine Reserve in the Indian Ocean

Over 275,000 people and a number of influential science and conservation organisations called on the UK Government to establish the territorial waters of the British Indian Ocean Territory as a Marine Reserve in 2010. ZSL was amongst the organisations that contributed to the science case for the creation of the reserve [2] and that helped to ensure its establishment. This decision was one of the most significant ways the UK could make a landmark contribution to global marine conservation and was part of the starting point for the Blue Belt programme where the UK government aims to protect over four million square kilometres of marine environment across the UK Overseas Territories. The designation also contributes greatly to a number of globally agreed targets, such as the IUCN World Conservation Congress target to protect 30% of each marine habitat in highly protected marine reserves by 2030.

The ‘no-take’ designation makes the 640,000km2 an IUCN Category 1 strict nature reserve meaning no extractive industries (fishing, mining, dredging) can take place. There is an exemption of a few miles around the island of Diego Garcia in the south which houses a military facility.

The future of the BIOT marine reserve

From 2010 to 2016 the BIOT marine reserve was the largest in the world. Since then it’s been overtaken by even bigger protected areas, some of them in other UK Overseas Territories such as the enormous Pitcairn Marine Reserve which is 834,000 km2. ZSL has played a key role in the creation of many of these new protected areas as well through its role in the Great British Oceans campaign.

Since 2010 ZSL has been working with many other organisations to better understand the astounding array of wildlife that lives in BIOT and has been making significant advances in marine science and conservation. We have worked closely with the BIOT administration in the Foreign and Commonwealth Office and with the Bertarelli Foundation to develop an ambitious programme of research to support ever better management of the marine reserve into the future.

Dominic Andradi-Brown

ZSL work in BIOT

The Bertarelli Programme in Marine Science

In 2017 the Bertarelli Foundation announced its new programme for marine science in BIOT. The programme builds on a series of expeditions, workshops and strategic plans to create a vision for the BIOT marine reserve as a global exemplar of science and conservation activities working to support effective management. From 2017 to 2021 the programme will be coordinated on behalf of the foundation by ZSL and comprises a team of 50 researchers from 14 institutions across the world studying all aspects of the animals and habitats of this amazing place. For more information, please see the Bertarelli Programme in Marine Science tab above.

Reducing the impact of plastics on the BIOT natural environment

On the 1st April 2019 we will begin a new project funded by Darwin Plus, a UK government initiative, to focus on the impact of plastic waste on the BIOT natural environment. The accumulation of plastic debris pollutes BIOT’s coastal ecosystems negatively impacting biodiversity, including populations of (endangered) green and (critically endangered) hawksbill sea turtles. Working with our partners at Swansea University and the BIOT administration we will investigate the impacts of macro and micro plastics on nesting sea turtles and work to develop long term strategies to enable systematic change, to reduce single-use plastics consumption and improve disposal and recycling practices on Diego Garcia.

Connect Chagos: People and wildlife

As part of ZSL’s commitment to global and local conservation capacity building we designed a delivered a four year programme called Connect Chagos. This multi-phase project to build environmental skills and awareness within the Chagossian community in the UK and overseas was a great success and we learnt huge amount from working alongside each other. We continue to stay interested and involved in the communities are looking for ways to continue this work into the future.

References

[1] Graham N.A.J., Pratchett M.S., McClanahan T.R., Wilson S.K. (2013) The Status of Coral Reef Fish Assemblages in the Chagos Archipelago, with Implications for Protected Area Management and Climate Change. In: Sheppard C. (eds) Coral Reefs of the United Kingdom Overseas Territories. Coral Reefs of the World, vol 4. Springer, Dordrecht

[2] Koldewey, H.J., Curnick, D., Harding, S., Harrison, L.R. and Gollock, M. (2010) Potential benefits to fisheries and biodiversity of the Chagos Archipelago/ British Indian Ocean Territory as a no-take marine reserve. Marine Pollution Bulletin, 60 (11). pp 1906-1915