Nha Trang Bay (NTB), located off the south-east coast of Vietnam, is a famous tropical tourist site. In the past, the bay was characterised by flourishing coral reefs but, by the end of 2019, more than 90% of the corals were gone. In addition to chronic and complex anthropogenic effects, there was an extensive outbreak of crown-of-thorns starfish (Acanthaster planci), the main natural predator of reef-building corals in the Indo-Pacific, among the remnant coral communities in NTB. By 2019, the mean abundance of A. planci in NTB reached 4.2 starfish per 100m2. Coral surveys conducted on 10 target sites over a 3-year period ending in 2019 revealed that mean coral cover decreased by 64.4% (coral loss varied from 43 to 95%). The greatest declines were in Acropora and Montipora, with 80.6 and 82.3% reductions in the coverage of these taxa respectively. The combination of nutrient enrichment and predator removal is thought to determine the extent of the outbreak of A. planci in the bay. The present trends in environmental conditions in NTB do not indicate a positive outcome for coral reef recovery in in this area in the near future.

中文翻译：

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越南芽庄湾珊瑚礁大面积减少：Acanthaster planci 爆发：一系列慢性干扰中的最后一个事件

芽庄湾 (NTB) 位于越南东南沿海，是著名的热带旅游胜地。过去，该海湾的特点是珊瑚礁繁茂，但到 2019 年底，90% 以上的珊瑚都消失了。除了慢性和复杂的人为影响外，在 NTB 的残余珊瑚群落中，还大规模爆发了刺冠海星（Acanthaster planci），它是印度-太平洋造礁珊瑚的主要天敌。到 2019 年，NTB 中 A. planci 的平均丰度达到每 100 平方米 4.2 只海星。在截至 2019 年的三年期间对 10 个目标地点进行的珊瑚调查显示，平均珊瑚覆盖率下降了 64.4%（珊瑚损失从 43% 到 95% 不等）。下降幅度最大的是 Acropora 和 Montipora，这些分类群的覆盖范围分别减少了 80.6% 和 82.3%。营养丰富和捕食者清除的结合被认为决定了 A. planci 在海湾中爆发的程度。NTB 环境条件的当前趋势并不表明在不久的将来该地区的珊瑚礁恢复会产生积极的结果。