Seventy-five years after the first coelacanth was trawled off East London and thirteen years after their discovery in the Sodwana Bay section of iSimangaliso Wetland Park, an international research collaboration under the auspices of the iSimangaliso Wetland Park Authority is underway. It is one of 148 research projects currently being undertaken in iSimangaliso, South Africa’s sole marine and terrestrial world heritage site. With only 46 marine world heritage sites globally iSimangaliso is considered one of the ‘Jewels of the Oceans’.
Sodwana Bay within iSimangaliso Wetland Park is rated as one of the top ten dive destinations in the world. The coral reefs contain over 1200 species of fish as well as a variety of underwater seascapes and marine flora and fauna, including the extremely rare coelacanth.
On the recently completed coelacanth research expedition, scientists worked alongside experienced Trimix divers, including Peter Timm, who discovered the coelacanths in Jesser canyon off Sodwana Bay and award-winning underwater photographer, Mr Laurent Ballesta, Director of Andromede Oceonology in France. Laurent raised the finances for the expedition and catalysed new research links between South African scientists and coelacanth researchers from the Natural History Museum in Paris. The South African Institute for Aquatic Biodiversity (SAIAB) and the South African National Biodiversity Institute (SANBI) are leading the research effort, building on previous research undertaken through the African Coelacanth Ecosystem Program. The collaborating Parisian scientists have had few opportunities to study living coelacanths and will now be able to combine field data with the results from detailed anatomical and other laboratory-based work on the coelacanth specimens from the National Museum’s collection.
“The expedition represented an important opportunity to build the knowledge base on coelacanths and marine ecosystems with new opportunities for science and deep sea research capacity. This knowledge will be used to inform the iSimangaliso Authority’s conservation and protection strategies for this flagship species” said Park CEO Andrew Zaloumis. The research is multi-disciplinary and involves bathymetric mapping, population and genetic research, behavioural studies and a broader exploration of biodiversity in the deep water habitats of iSimangaliso.
iSimangaliso Wetland Park was listed as South Africa’s World Heritage site in 1999 in recognition of its unique ecosystems and high biodiversity. The Park forms one of only two marine world heritage sites within the Indian Ocean region. With increasing impacts on marine world heritage sites from climate change, pollution, habitat destruction, overfishing and invasive species, international research collaborations like the coelacanth expedition are becoming more important.
The research expedition was linked with a deep mixed-gas diving team and the production of a science documentary. Trimix divers documented the first three coelacanths in iSimangaliso in 2000 and have added at least six new coelacanths into the catalogue that showcases the distinct spot patterns of each individual. They have also improved on the photographs of several known coelacanths and have made a valuable contribution to the understanding of South Africa’s coelacanth population. The divers are more manoeuvrable than either submersibles or Remotely Operated Vehicles (ROVs) and are able to use new and advanced technology to capture imagery of the coelacanths to study their unique features and behaviour. This included three-dimensional videography with a high-tech camera affectionately known as “the giraffe”. As part of the research expedition, divers attempted to feed a coelacanth to assess the role of the coelacanth’s inter-cranial joint in feeding. Divers placed a hydrophone in a cave where most coelacanths have been observed in the hopes of finding out whether coelacanths made any noises. A low light camera was also positioned at the entrance to document the presence of fish at set intervals. This data is still being processed.
The expedition also used a Remotely Operated Vehicle (ROV) which undertook a wider search for coelacanths in the Park. iSimangaliso Wetland Park has an extensive marine protected area and the ROV completed dives from Island Rock Canyon in the north to Chaka Canyon in the south. No new coelacanth locations were found. Highlights of the ROV dives included sightings of a thresher shark on the canyon margin, a one metre long red steenbras, a first sighting of a ‘seventy four’ fish in the canyons and other new records and potential new species.
