Red List of Ecosystems of coral reefs of the Western Indian Ocean

The IUCN Red List of Ecosystems is a global framework for assessing the status of ecosystems. It aims to support conservation, resource use, and management decisions by identifying ecosystems most at risk of biodiversity loss using a unified standard.  It is applicable from sub-national to global levels and uses the same vulnerability categories as the IUCN Red List of Species (e.g. Critically Endangered, Endangered, etc.) plus a new category Collapsed (analogous with Extinct).



The RLE may be assessed through five separate criteria, relating to declining and restricted ecosystem distribution, degradation of abiotic and biotic processes, and quantitative models of ecosystem health.


An RLE may be used for many different purposes, to improve decision-making and sustaining vulnerable ecosystems.

Under CORDIO’s 5-year project ‘’Innovating and sharing knowledge for coastal resilience in Eastern Africa’’ funded by the Norwegian development agency Norad, CORDIO, together with international and regional partners will be undertaking a vulnerability assessment of coral reefs of the WIO.

The assessment builds on existing regional data sharing and reporting on coral reefs to generate an output targeting decision-makers. See the brochure on the right for more details. Globally, only two assessments of coral reefs have been completed, for the Caribbean region and the Meso-American Reefs.

Timeline and activities

The project ran from January 2019 to August 2020. The main activities were:
Inception Workshop – Held in Mombasa from 12-15 March 2019 and attended by 25 participants
Call for data made in April 2019. Overall, 37 institutions and individuals agreed provided data for the assessment, which also resulted in an update of the WIO GCRMN coral reef datasets
Validation Workshop – Held in Mombasa from 21-22 January 2020 and attended by 30 participants
– Regional analysis and assessment completed – May 2020
– Scientific manuscript submitted to Conservation Letters for peer-review and Technical report submitted to IUCN RLE Team for review – August 2020
– Abstract accepted for oral presentation at the International Coral Reef Symposium (ICRS) 2021 (Bremen, Germany)

  • Partners and support

  • The project is led by CORDIO East Africa, assisted by the IUCN Coral Specialist Group (CSG) and the IUCN global RLE team and in partnership with numerous research partners from the WIO Coral Reef Network and internationally.
Validation Workshop, January 2020


  • Next steps

  • – Key findings and messages will be disseminated at national, regional and global events once the paper is accepted for publication, with attempts made to integrate findings into relevant policy mechanisms
    – Following the completion of the WIO coral reef RLE assessment, CORDIO is now focusing on undertaking more localised assessments in 3 countries, namely Kenya, Tanzania and Mozambique. The aim of the assessments are to strategically assess reefs to help prioritize areas to target effective management actions that can support reef and community resilience. More information is available on this page.