Restoration of coral reef off Kotok
Pulau Seribu is an island group off the coast of Jakarta. Its ecology is under severe pressure due to pollution, over-fishing and tourism. Since 2014, Witteveen+Bos has supported the Jakarta Animal Aid Network (JAAN) which runs a Wildlife Rehabilitation Centre on the island of Kotok. Here, coastal erosion threatens the beaches on which turtles nest and lay their eggs, while fishing is severely damaging the coral reef.
Based on our design and using locally sourced materials, large numbers of volunteers have made and erected groynes which keep the sand in place and help to restore the beaches. In another project, an innovative technique is being used to promote coral growth. Coral is attached to metal propagation frames which are lowered into the sea. An electric current generated by small photovoltaic cells is then passed through them, resulting in the accumulation of calcium carbonate. This is readily absorbed by the coral, which then grows five times more quickly. The frames also act as buffers, protecting the coastline from the pounding of the waves. This helps to create new habitats. Just over a month into the project, divers found the coral to be thriving – a good indication of rapid growth potential. Monitoring will continue for several years. There has been significant interest from marine contractors because coral restoration after a civil engineering project is a time consuming and expensive process.