Long-term shifts in the colony size structure of coral populations along the Great Barrier Reef

A significant decline in coral colony abundances across all size classes and taxa has been observed along the Great Barrier Reef, with particularly severe impacts in northern and central regions following mass bleaching events in 2016 and 2017. While large colonies appear stable in relative terms, their absolute numbers have sharply decreased, raising concerns about the potential for recovery of older, fecund corals amid increasing disturbance frequency and intensity. The study, which compared current data to historical baselines from 1995/1996, also found that smaller colonies have systematically declined across regions, habitats, and taxa, indicating a broader erosion of recruitment and resilience in coral populations.

Dietzel, A., Bode, M., Connolly, S. R., & Hughes, T. P. (2020). Long-term shifts in the colony size structure of coral populations along the Great Barrier Reef. Proceedings of the Royal Society B: Biological Sciences, 287(1936), 20201432. https://doi.org/10.1098/rspb.2020.1432