Being an island, Sri Lanka is rich in coastal and marine habitats. Sub-tidal habitats such as coral and rocky reefs are abundant, along with large soft bottom habitats. In addition, inter-tidal and coastal habitats are an important part of the marine ecosystem and provide shelter for a large number of plant and animal species. The coastline along the Rekewa, Ussangoda and Kalametiyah area is particularly rich in both animal and plant diversity, of both national and international importance. However, increasing population, poverty, over-fishing, shell mining, coral mining and overgrazing by livestock are creating serious threats to both aquatic and terrestrial ecosystems. IUCN Sri Lanka conducted an assessment of the biodiversity of the inland and sub-tidal ecosystems within the RUK area as part of a project supported by the Global Environment Facility (GEF) of the UNDP to conserve the biodiversity of this globally significant area.