Coral reef collapse in South-Central Vietnam: a consequence of multiple negative effects
17/03/23 09:13AM
Tkachenko, Konstantin S; Dung, Vu V; Ha, Vo T; Huan, Nguyen H.  Aquatic Ecology; Dordrecht Vol. 57, Iss. 1, (Mar 2023): 65-83. DOI:10.1007/s10452-022-09994-2
Abstract: Repeated coral reef surveys conducted in 2016–2021 in the coastal area of Nui Chua National Park in Ninh Thuan Province (South-Central Vietnam), formerly one of the richest coral areas in the Vietnamese coastal waters of the South China Sea, revealed dramatic degradation of coral communities over a five-year period. Coral cover decreased by 93% and coral diversity by six-fold. This phenomenon has resulted from a long-term outbreak of crown-of-thorns starfish Acanthaster sp. (COTS) reinforced by sea surface temperature anomalies in June 2019. The last survey, conducted in the target monitoring site in May 2021, revealed that the outbreak of COTS had ceased together with the disappearance of food sources for this starfish. Predator removal caused by overfishing and to some degree, nutrient enrichment resulting from the local seasonal upwelling, apparently determined the extent of the COTS outbreak. Degraded upstream coral reefs in the adjacent districts do not suggest coral recovery in this area in the near future.