Nature Seychelles and Black Pearl Seychelles Ltd. in Praslin have initiated a unique collaboration under the Reef Rescuers project, which is restoring coral reefs in Seychelles. The aim of the collaboration is to transplant 30 aquaculture-raised giant clams (Tridacna maxima) into the wild as part of the ongoing project. During the first step, 5 clams have been relocated to a transition pool, where they are being acclimated and readied for transplantation in the wild.
“The history of giant clam aquaculture in Seychelles has in a way now come full circle,” says Dr. Nirmal Shah Chief Executive of Nature Seychelles. In 1989 Shah wrote a project for the Seychelles Fishing Authority (where he was Assistant Director of Research) for a feasibility study of giant clam aquaculture in Seychelles. The project was funded and Shah was trained in giant clam aquaculture in the Pacific islands.
Coincidentally soon after, Roald and Kari Nilsen arrived in Seychelles with plans to set up a business in giant clam aquaculture. They set up Black Pearl Seychelles Ltd. and studied giant clam aquaculture in Australia. They used their new skills to raise the clams in a facility at Praslin Island as a complementary activity to their oyster pearl aquaculture.
A month ago, Nature Seychelles' Reef Rescuers staff - Project Coordinator, Dr. Sarah Frias-Torres and Technical Officer, Claude Reveret - approached Black Pearl Seychelles Ltd. manager Anders Hennie to evaluate the feasibility of a giant clam transplantation experiment in the wild. As a result of their meetings, Roald and Kari Nilsen generously agreed to donate 30 of their aquaculture-raised giant clams for the experiment.
Giant clams were once common inhabitants of Indo-Pacific coral reefs, but overfishing has significantly reduced their numbers and caused local extinctions. Most clam species are filter-feeders, filtering out food particles from water they let pass through their bodies. However, giant clams have microscopic algae in their tissues and depend on the algae's photosynthesis for food. For this reason, giant clams need clean water so the sunlight can reach them. These are the same conditions needed for coral reefs to thrive.
Dr. Shah said the donation is extremely useful as it will assist in what he calls the “sea-scaping” of the area where corals are being transplanted by the Reef Rescuers. “We want to establish a fully functioning coral reef and clams are an important component of healthy reefs. The ultimate aim of our project is to restore ecosystem functions of coral reefs, and the transplantation of giant clams is yet another step in this direction.”
Nature Seychelles' reef restoration project is financially supported by USAID and the Government of Seychelles through the GOS-UNDP-GEF Protected Areas Project.
Photos: Top left - One of the giant clams (Tridacana maxima) donated to Nature Seychelles by Black Pearl Seychelles Ltd. Right: Anders Hennie, Black Pearl Seychelles Ltd, donates one of the 30 giant clams to Katherine Rowe, Reef Rescuers dive leader.