Deoxygenation following coral spawning and low-level thermal stress trigger mass coral mortality at Coral Bay, Ningaloo Reef

A catastrophic mass coral mortality event at Coral Bay, Ningaloo Reef, was triggered by deoxygenation following the 2022 coral spawning event, combined with low-level thermal stress. The study documented a dramatic shift in benthic communities, with coral cover plummeting from over 70% to just 1.16%, while turf algae dominance surged to 78.8%. Coral generic richness dropped by 84.61%, wiping out previously dominant genera like Acropora and Montipora. The research used long-term monitoring data across nine sites, comparing pre- (2016–2018) and post-spawning (2021 vs. 2022) conditions to quantify the ecological impact. Isolated survivors, such as Porites spp., suggest potential resilience mechanisms warranting further study. The findings underscore the dual threat of deoxygenation and thermal stress to reef ecosystems, emphasizing the need for long-term recovery monitoring to assess broader ecological, socio-economic, and cultural implications.

Richards, Z. T., Haines, L., Ross, C., Preston, S., Matthews, T., Terriaca, A., Black, E., Lewis, Y., Mannolini, J., Dean, P., Middleton, V., & Saunders, B. (2024). Deoxygenation following coral spawning and low-level thermal stress trigger mass coral mortality at Coral Bay, Ningaloo Reef. Coral Reefs, 43(2), 443–453. https://doi.org/10.1007/s00338-024-02476-x