The current state of the atoll

Saint Brandon, despite the threats it faces, remains one of the most ecologically intact coral reef and seabird ecosystems in the western Indian Ocean. The 1998 World Bank Management Plan concluded that the marine ecosystem and surrounding coral reefs are a unique area that is ecologically largely intact. Every subsequent survey — the Mauritian Wildlife Foundation expeditions from 2010 onwards, the Cole flora and fauna surveys of Île Coco between 2010 and 2019, the Monaco Explorations Indian Ocean Mission of 2022, the joint Odysseo and Saint Brandon Conservation Trust expedition of 2024 — has confirmed that assessment. The reef supports at least thirty-six species of hard coral, six of soft coral, and the longest algal ridge in the Indian Ocean. The bird colonies hold over a million seabirds at peak season. The sea-turtle nesting population is one of the most important in the region. Live coral cover ranges between three and thirty-five percent across the surveyed sites, with the highest cover on the western reef wall. Fish biomass at five of eight sampled sites in the most recent surveys exceeded the western Indian Ocean regional benchmark — a measure of how productive an intact reef can still be when it has been spared the pressures that have flattened most others.What kept Saint Brandon in this condition is partly its remoteness, partly the long-term fishery management of the Raphael Fishing Company, and partly the quiet good fortune that it has never been heavily exploited for the aquarium trade or the live reef-fish trade that has destroyed reefs across South-East Asia. It is one of the last reefs in the Indian Ocean where a careful snorkeller, drifting with the current, can still see what a healthy coral community is supposed to look like.But intact is not invulnerable. Several pressures on Saint Brandon are documented and ongoing.

The active threats

Shipwrecks

The Yu Feng No. 67 sits on the reef as of writing, leaking diesel and rotting bait into the lagoon. Before her, the Sea Master (Mauritian, June 2021, four tonnes of fuel oil on Albatross Island), the Alam Manis (bulk carrier, February 2017), the Kha Yang (Malaysian, January 2015, with 250,000 litres of fuel recovered), the Team Vestas Wind (Volvo Ocean Race, November 2014, a US$6 million racing yacht abandoned on the reef), an unnamed tuna longliner (2012, the subject of the major van der Schyff study), and historic wrecks stretching back to the Bom Jesus in 1591 and the Arnhem in 1662. The reef is a magnet for groundings. Each wreck leaves behind dead coral, possible heavy-metal contamination, lost gear, and persistent organic pollutants that take decades to dissipate.

Invasive species

Rats are confirmed on Île Raphael, Île Poulailler, and Puits à Eau, and likely on Pearl and Sirène. Rabbits remain on L’île du Sud, where they were introduced decades ago and have never been removed. The Mauritian Wildlife Foundation has successfully eradicated rats from the 25-hectare Île aux Aigrettes off the main island — a programme that proves what is possible. The Cole surveys of Île Coco between 2010 and 2019 identified rat and mouse removal as the single most impactful conservation action available at Saint Brandon, with a particular focus on protecting the smaller tern and noddy nesting colonies whose eggs and chicks are most vulnerable.

Marine debris

A 2016 study counted approximately fifty thousand individual items of marine debris on Saint Brandon’s shores. Seventy-nine percent of it was plastic, originating mainly from South-East Asia, the Indian subcontinent, and the Arabian Sea. The trash arrives from elsewhere. It accumulates here because Saint Brandon’s reef is a sieve, and because there is no one to clean it.

Poaching

Of birds, eggs, and turtles. Historically severe; now reduced but not eliminated, particularly during periods when Coast Guard surveillance gaps coincide with passing fishing vessels.

Climate change

Coral bleaching events are documented but localised. The reef as a whole is in better condition than most in the Indian Ocean — but the trajectory of warming and acidification is not in Saint Brandon’s favour. The 2024 global bleaching event affected reefs across the Indo-Pacific, and the long-term outlook for shallow coral systems anywhere in the tropical world is uncertain.

Persistent organic pollutants

A 2021 study by van der Schyff and colleagues quantified persistent organic pollutants in seabird eggs from Saint Brandon — DDT, PCBs, and other long-range pollutants are present, though at concentrations lower than in similar studies elsewhere. The authors concluded that the atoll serves as an ideal reference site for tropical Indian Ocean baseline monitoring. But the pollutants are there.

Ciguatera fish poisoning

The biotoxin produced by certain dinoflagellates accumulates in larger reef-fish and makes them inedible. The presence of Gambierdiscus toxicus has been confirmed at Saint Brandon. The extent of the ciguatera risk remains unresolved and is the subject of ongoing research at the Albion Fisheries Research Centre.

The Raphael Fishing Company holds the permanent grant on thirteen of the islands, confirmed by the 2008 Privy Council ruling. The company is part of the Jean Boulle Group, and its contemporary conservation work is led by Nathalie Boulle in close partnership with the Mauritian Wildlife Foundation. The company controls invasive foreign species across the islands under its grant, monitors plastic pollution and the presence of heavy metals, and works to make the archipelago more accessible to Mauritians on a long-term, sustainable basis — a quietly important commitment, given how few citizens of the Republic of Mauritius have ever seen the islands their country administers. In 2016 the company organised and funded a seven-day fact-finding mission with three internationally acclaimed scientists: Professor Henk Bouwman, an ecotoxicologist specialising in environmental pollution and bird ecology; Professor Tony Martin, one of the world’s foremost experts on marine mammals; and Dr Nik Cole, herpetologist and Islands Restoration Manager at the Mauritian Wildlife Foundation, who would go on to lead the successive Cole flora and fauna surveys of L’Île Coco. The data and the relationships built during that week underpin much of the conservation work being done at Saint Brandon today. The Raphael Fishing Company is, at the time of writing, ninety-three years old. The continuity of stewardship that figure represents — a single operator caring for the same islands for nearly a century — is one of the reasons Saint Brandon remains intact.

The Saint Brandon Conservation Trust was established in 2023 as the principal non-governmental conservation body for the archipelago. It is registered in Mauritius and operates as an independent charitable organisation whose mission is to protect, restore, and conserve the atoll, with the eventual goal of securing UNESCO World Heritage status. Its founding partners include the Raphael Fishing Company, the Odysseo Foundation, and Fly Castaway. The Trust published its first five-year plan covering the period 2025 to 2030 in late 2025, alongside its first annual report. Its priorities are biosecurity, invasive species removal, marine debris management, and the long-running campaign for UNESCO recognition. It is the youngest of the institutions on this list, and in the short time since its founding it has already done more to coordinate the previously fragmented conservation effort than any other body.

Fly Castaway runs the catch-and-release saltwater fly-fishing operation on Île Raphael — one of the few sustainable commercial uses of the archipelago that genuinely contributes to its long-term protection through revenue, observation, and active stewardship by experienced guides who notice things. Their guides have been on the water at Saint Brandon for years and contribute informal observations that the formal scientific surveys cannot match in continuity. Fly Castaway is also a founding partner of the Saint Brandon Conservation Trust, and its commercial model — high-cost, low-impact, catch-and-release — has become the template for sustainable visitor access to the atoll.

The Mauritian Coast Guard maintains a permanent rotational presence on Île Raphael of approximately five personnel, responsible for the enforcement of fishing regulations, the response to shipwrecks, and the formal notification of arriving vessels. It is, in the absence of better resourcing, the only on-the-ground enforcement body in the archipelago.

What still needs to happen

For all the architecture and all the science, the conservation framework at Saint Brandon is still missing three things that the 1998 World Bank Management Plan recommended and that successive reports have repeated.

A formal UNESCO World Heritage designation

The Mauritian government recommended this in 2004. The recommendation, more than twenty years old, has not yet been acted on. UNESCO status would bring international attention, international funding, and international protection. Its absence is the single largest gap in Saint Brandon’s legal protection.

A formal IMO Particularly Sensitive Sea Area designation

Greenpeace and the International Maritime Organization have separately called for this. The designation would require international shipping to avoid Saint Brandon, which would directly address the shipwreck problem. It has not been granted.

The full implementation of the 1998 Marine Protected Area Management Plan

The Mauritian government approved the Blueprint in 2004. Twenty-one years later, parts of it remain unimplemented — including the formal demarcation of the Turtle Lagoon Marine Park and the Cocos Island Marine Park, the establishment of monitoring infrastructure, and the rationalisation of the zoning regime. The legal framework exists. The resourcing does not.
The path forward is not theoretical. It is mapped, repeatedly, in successive reports. What is required is political will, sustained funding, and the patience to outlast the slow-grinding pace of governmental decision-making.