A rapid biodiversity assessment of fish communities in the waters surrounding the Save Our Seas Foundation–D’Arros Research Centre provided more than just a list of fish species. It revealed an essence of place. Writing from D’Arros Island, Clare Keating Daly reports on the findings and the place.
Place is a slippery thing. Read a guidebook, zoom in on a map, search a tag or a keyword, walk its shores or its roads – there are many ways to feel as though we know a place. And yet, a place’s essence, its contents and components remain concealed, unknown. As wilderness, wildness and the ability to find solitude in the natural world disappear before our eyes, it can feel as though there is little left to discover, that the book on nature can be closed. But there is still so much to learn, to record, to preserve. There is so much at risk of slipping away, of remaining unknown.
Our planet harbours unimaginable biodiversity, an estimated 8.7 million species. Today, researchers believe that roughly 85% of these species have not yet been described. Which is to say, we still have a long way to go. We have much to learn about what kind of place this planet is, and the best way to begin to understand this is to act locally.
A constellation of islands scattered some 1,500 kilometres (930 miles) off the coast of eastern Africa, the Seychelles is, in a way, surrounded by fishes. Nonetheless, marine fishes are not a hot topic of study in the country and even less so in the Outer Islands of the Amirantes Archipelago, home of the SOSF-D’Arros Research Centre. There is wilderness here, wildness under the waves. There is much that remains unknown. Thus to understand more about the biodiversity of the Seychelles, what better place to start than with its fishes.
Although the research centre’s reef fish monitoring programme is entering its eighth year, knowledge of the local fishes was limited to a record of the species encountered during general research activities, a list containing approximately 220 names. Suspecting that more fish species could be found in the diverse range of marine habitats, in May 2017 a team of three researchers set out to establish a benchmark.
The team consisted of SOSF-D’Arros Research Centre’s research director Dr Ryan Daly, consultant Dr Guy Stevens and research assistant Justin Blake. Free diving and on scuba, they armed themselves with cameras and clipboards in the field and Fishbase.org and identification guides in the lab. Over 19 days, spending 84 hours underwater, they undertook a rapid biodiversity assessment of the coral reefs and associated habitats found around D’Arros Island and St Joseph Atoll.
Roving through meadows of sea grass and across sand flats, shining a light into the darkest caves and exploring the murky waters of the atoll lagoon, the team more than doubled the number of known fish species in the waters surrounding the island and the atoll. They recorded 514 reef-associated fish species in 71 families, photographing 73% of these records for positive identification.
A biological field station based on D’Arros Island in the Amirantes Group, Seychelles, the SOSF D’Arros Research Centre (SOSF–DRC) conducts research on the pristine D’Arros Island and St Joseph Atoll and the waters around them. In recognition of the islands’ outstanding natural values, the research centre was established in 2004 and tasked with becoming a regional centre of excellence for marine and tropical island conservation. Initially, collaborations were established with local and international institutions and baseline ecological surveys were conducted in the various habitats. Over the ensuing years an increasing number of research projects and monitoring programmes were implemented in response to questions raised by the baseline surveys and by visiting scientists. More recently, the centre expanded its activities to include ecosystem restoration and environmental education.
Today the SOSF–DRC boasts the longest-running nesting turtle monitoring programme in the Amirantes and the most detailed and technically advanced coral reef monitoring programme in the Seychelles, making use of techniques such as stereo-video photogrammetry, photoquadrats, remote underwater video systems (BRUVs) and visual census. The research centre also maintains the largest acoustic receiver array in the Seychelles, which monitors the local movements of sharks, manta rays, stingrays, turtles and fish. Since its inception in 2004, the centre has initiated no fewer than 36 research projects in collaboration with more than 26 conservation institutions. The projects have resulted in 10 peer-reviewed scientific papers, one PhD and one MSc dissertation, five conference presentations and 27 scientific reports.