The Coral Reefs of Eilat – Past, Present and Future: Three Decades of Coral Community Structure Studies

Here, I shall present a brief review of ca.35 years of our studies on changes in the coral species diversity and community structure at Eilat, Red Sea, at several scales in space and time. In the following, I shall: (1) summarize the geographical setting and the geological, physical and biological characteristics of the Gulf of Eilat/Aqaba, then point out the uniqueness of the coral reefs of Eilat, which are situated at the most northerly boundary of coral reef distribution,yet exhibit extraordinarily high within-habitat coral species diversity; (2) present the changes that took place in coral species diversity and community structure on the reef flats in the northern Gulf of Aqaba/Eilat (during the 1969–1980), due to natural disturbances (extreme midday low tides) and man-made perturbations (chronic oil spills); (3) discuss possible mechanisms that generate and maintain the high within-habitat coral diversity typifying pristine reefs in the Gulf of Eilat/Aqaba; (4) discuss the opposite mechanisms that caused a dramatic decrease in coral abundance and living cover at the Eilat Coral Nature Reserve (ECNR) during 1986–2000.I will also point out two major anthropogenic disturbances: first, eutrophication caused by Eilat’s sewage discharge to the sea until 1995; and second, further eutrophication originating from intensive net pen mariculture off the northern coast of Eilat,which exponentially expanded activity from 1994–1995 to present times.The grave implications for the coral reefs of Eilat caused by this chronic eutrophication will be presented. Finally, (5) I conclude with a warning that, at present, the coral reefs of Eilat are severely damaged and subsist in a critical state. If eutrophication of the northern Gulf is not halted immediately, the final collapse and total destruction of the unique coral reefs of Eilat are certain. In their present fragile state, the only chance for the restoration of the Eilat reefs is extreme and instant protection measures against all man-made disturbances.