The continuing decline of coral reefs in Bahrain

Historically coral reefs of Bahrain were among the most extensive in the southern basin of the Arabian Gulf. However, Bahrain’s reefs have undergone significant decline in the last four decades as a result of large-scale coastal development and elevated sea surface temperature events. Here we quantitatively surveyed six sites including most major coral reef habitats around Bahrain and a reef located 72 km offshore. Fleshy and turf algae now dominate Bahrain’s reefs (mean: 72% cover), and live coral cover is low (mean: 5.1%). Formerly dominant Acropora were not observed at any site. The offshore Bulthama reef had the highest coral cover (16.3%) and species richness (22 of the 23 species observed, 13 of which were exclusive to this site). All reefs for which recent and historical data are available show continued degradation, and it is unlikely that they will recover under continuing coastal development and projected climate change impacts.

► Historically Bahrain had extensive coral reefs, but these have been degraded in recent decades.
► Quantitative surveys were conducted at six sites including Bahrain’s most extensive reef habitats.
► Algae now dominate reefs (72% cover) and coral cover is low (5.1%); Live Acropora were not observed.
► Decline of these reefs will likely continue under current development and future climatic impacts.