Oxygen depletion is well recognized for its role in the degradation of tropical coral reefs. Extreme acute hypoxic events that lead to localized mass mortality and the formation of ‘dead zones’ (a region where few or no organisms can survive due to a lack of oxygen) are particularly concerning as they can result in wide-ranging losses of biodiversity, ecosystem productivity and functioning, economic prosperity, and wellbeing. In March of 2022, the annual coral spawning event at Bills Bay (Coral Bay, Ningaloo Reef, Western Australia) coincided with elevated seawater temperature, calm weather conditions and a flood tide resulting in coral spawn becoming trapped in Bills Bay. Immediately after, there was a mass fish kill, which is believed to have been caused by local eutrophication resulting in severe oxygen depletion. The impact the deoxygenation and thermal stress event had on benthic communities has not yet been quantified; hence, the principal aim of this study is to document the extent of change that occurred in the benthic communities before and after the 2022 coral spawning event over a spatial gradient from the nearshore to mid-reef. Percent coral cover in the Bay decreased from 55.62 ± 2.26% in 2016–2018 and 70.44 ± 5.24% in 2021 to 1.16 ± 0.51% in 2022. Over the same period, the percent cover of turf algae increased from 27.40 ± 2.00% in 2016–2018 and 24.66 ± 6.67% in 2021 to 78.80 ± 3.06% in 2022, indicating a dramatic phase shift occurred at Bills Bay. The abundance of healthy coral colonies recorded on replicated belt transects at nine sites declined from 3452 healthy individuals in 2018 to 153 individuals in 2022 and coral generic richness decreased by 84.61%, dropping from 26 genera in 2018 to 4 genera in 2022. Previously dominant genera such as Acropora, Montipora and Echinopora, were extirpated from survey sites. Isolated colonies of massive Porites spp. and encrusting Cyphastrea sp. survived the event and understanding the mechanisms underpinning their greater survivorship is an important area of future research. Long-term monitoring is recommended to track the community recovery process and improve our understanding of the longer-term implications of this acute mortality event on the ecological, socio-economic and cultural values of Ningaloo Reef.

缺氧因其在热带珊瑚礁退化中的作用而得到广泛认可。导致局部大规模死亡和“死亡区”（由于缺氧而很少或根本没有生物体能够生存的区域）形成的极端急性缺氧事件尤其令人担忧，因为它们可能导致生物多样性的大范围损失，生态系统生产力和功能、经济繁荣和福祉。 2022 年 3 月，比尔斯湾（西澳大利亚州宁加洛礁珊瑚湾）一年一度的珊瑚产卵活动恰逢海水温度升高、天气平静和涨潮，导致珊瑚产卵被困在比尔斯湾。紧接着，发生了大规模鱼类死亡事件，据信这是由于当地富营养化导致严重缺氧造成的。脱氧和热应激事件对底栖生物群落的影响尚未量化；因此，本研究的主要目的是记录 2022 年珊瑚产卵事件前后从近岸到礁石中部的空间梯度上海底群落发生的变化程度。海湾珊瑚覆盖率从 2016 年至 2018 年的 55.62 ± 2.26% 和 2021 年的 70.44 ± 5.24% 下降到 2022 年的 1.16 ± 0.51%。同期，草皮藻类覆盖率从 2016 年的 27.40 ± 2.00% 增加–2018 年和 2021 年的 24.66 ± 6.67% 到 2022 年的 78.80 ± 3.06%，表明比尔斯湾发生了巨大的相移。九个地点的复制带样带上记录的健康珊瑚群落丰度从 2018 年的 3452 个健康个体下降到 2022 年的 153 个个体，珊瑚属丰富度下降了 84.61%，从 2018 年的 26 属下降到 2022 年的 4 属。诸如鹿角珊瑚（Acropora）、 Montipora和Echinopora 等，已从调查地点灭绝。大量滨珊瑚属的孤立菌落。和结壳Cyphastrea sp。在这次事件中幸存下来，了解支撑其更大生存能力的机制是未来研究的一个重要领域。建议进行长期监测，以跟踪社区恢复过程，并提高我们对这一急性死亡事件对宁加洛礁生态、社会经济和文化价值的长期影响的了解。