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Reef Restoration Project

Working towards restoring Pemba's damaged reefs to enhance natural coral growth and species diversity

One of the most significant threats to the coral reefs of Pemba is from local fishing activity. Illegal dynamite fishing was used in the past; this caused extensive damage to the reef. Although this destructive fishing method is no longer practised in Pemba, the coral has been slow to recover and continue to experience pressures from other potentially damaging fishing methods. These activities have left large sections of what used to be a vibrant, healthy coral reef looking like a barren wilderness. Our research to-date suggests that natural recovery has been slow because the reef slope is steep, the rubble which covers the seabed is unstable and the currents can be strong, causing a shifting substrate. Therefore, any new corals which do settle become easily detached by wave energy, which moves the rubble down the slope.
Our Reef Restoration Project aims to stabilise the reef slope so that corals can settle on a solid substrate and the reef can re-establish naturally. To do this we are trialling two different methods over several 5 meter by 5 meter areas: low-lying frames made from reinforcing steel bar (rebar) and a steel mesh. To make the surface of both our designs more suitable for coral recruit settlement, we will coat the frames and mesh in beach sand. Both methods have been designed with the primary aim of stabilisation as our research has found that natural coral recruitment to the reef is high. Once the substrate is successfully stabilised, we expect that small coral recruits which settle will be able to grow into mature colonies. The two methods have been selected as they are suitable for upscaling to cover a large area of reef. We are hopeful that by finding an effective design which prevents the seabed being disturbed by wave action, coral will be able to regrow, and the reef environment recover.

We want to introduce these reef restoration techniques within the Kwanini Marine Protected Area (KMPA) to encourage regeneration of the reef. Because the reefs in the KMPA are protected from any kind of fishing pressure the area is considered a suitable location to trial restoration techniques. Once the structures have been installed, we will monitor how successful they are in stabilising the substrate and promoting natural coral recruitment and growth. Having determined which techniques work best in the KMPA we want to extend the restoration efforts to other damaged reefs along the western coast of Pemba Island.
Here’s how you can support our Reef Restoration Project:
  • Make a donation to help fund the materials needed for the restoration efforts.
  • Sponsor a 5 m x 5 m area of reef restoration
  • Our Projects - Main Page