Historical coral reef benthic cover for the Western Indian Ocean (1970-2008)

Benthic cover data (percent cover) for the Western Indian Ocean. Data have been extracted from published sources through a systematic literature review, and compiled with previously unpublished datasets. Data was collected prior to 2008 through quantitative coral reef surveys (e.g., Line or Point-Intercept-Transects, photo or visual quadrats) and visual estimates. Particular attention was given to compiling live hard coral cover and macro and turf algae cover data due to their importance as principal measures of coral reef health. Data are from 10 Western Indian Ocean countries and territories: Kenya, Seychelles, Tanzania, Mozambique, Comoros, Mayotte, Madagascar, Reunion, Mauritius and South Africa.

Data were extracted from grey literature (technical reports, books, and book chapters), scientific journal papers (articles and reviews) and project reports. 

Data were generally reported as summarised mean cover values at a monitoring site level. Data aggregated at broader geographic scales was also included (e.g., “northern Kenya”), or other classes (e.g., “unspecified 9 sites (protected)”). 

Data found in more than one publication were identified and cross-referenced to the other sources. Locations were ordered hierarchically by Country, Sector, Site and Station. In some cases, the same site or station may have multiple entries for the same year because of surveys of different reef zones or depths, and this information is provided to enable a distinction to be made. The exact date or year of survey was not clear in a few publications, and this has been recorded in the Year column as either combined years, e.g. 1998/99, general time period, e.g. mid - 1990s, or if no information is available, as ‘n.d’.