The Western Indian Ocean contains 16% of the world’s coral reefs, and the region is now thought to host the second peak of coral reef biodiversity globally. Coral reef ecosystems underpin the economies of the countries in the region, particularly fisheries and tourism sectors, and provide livelihood opportunities and income for local communities. However, anthropogenic threats at all scales, such as from fishing, development and climate change, are all increasing with human population growth and local to regional development. Western Indian Ocean coral reefs experienced widespread coral bleaching during the first global coral bleaching event in 1998, in which 30-50% of corals were estimated to have died.