Absolute abundance of <i>Echinothrix diadema</i> in the Mombasa Marine National Park and Reserve in September-October 1997, together with percentages of substrate cover (seagrasses, algae, corals, sediment) at the different sampling locations. The data were digitized by VLIZ from the original report: Van Hout, T. (1998). Patterns of distribution of Echinothrix diadema (Echinodermata: Echinoidea) in the Mombasa Marine National Park and Reserve, Kenya. MSc Thesis. Vrije Universiteit Brussel: Brussel. 71 pp.