Coral bleaching on Great Barrier Reef reaches 'catastrophic' levels
A team of marine scientists from the University of Sydney has published the first peer-reviewed study documenting the devastating coral bleaching events that occurred on the southern Great Barrier Reef in early 2024.
Led by Professor Maria Byrne from the School of Life and Environmental Sciences, the research highlights the alarming impact of unprecedented marine heat waves on coral ecosystems, raising urgent concerns for marine biodiversity and the communities that depend on these vital ecosystems.
The study, published in Limnology and Oceanography Letters, provides critical insights into the extent of coral bleaching and mortality during the 2023–2024 global marine heat wave. The research team meticulously tracked the health of 462 coral colonies at the University of Sydney's Great Barrier Reef research station at One Tree Island over a period of 161 days.
The study, published in Limnology and Oceanography Letters, provides critical insights into the extent of coral bleaching and mortality during the 2023–2024 global marine heat wave. The research team meticulously tracked the health of 462 coral colonies at the University of Sydney's Great Barrier Reef research station at One Tree Island over a period of 161 days.
The results revealed that 66% of the colonies were bleached by February 2024 and 80% by April. By July, 44% of the bleached colonies had died, with some coral genera, such as Acropora, experiencing a staggering 95% mortality rate.
Professor Byrne said, "Our findings underscore the urgent need for action to protect coral reefs, which are not only biodiversity hotspots but also crucial for food security and coastal protection. The southern Great Barrier Reef, despite its protected status, was not immune to the extreme heat stress that triggered this catastrophic bleaching event."
Professor Byrne said, "Our findings underscore the urgent need for action to protect coral reefs, which are not only biodiversity hotspots but also crucial for food security and coastal protection. The southern Great Barrier Reef, despite its protected status, was not immune to the extreme heat stress that triggered this catastrophic bleaching event."
Bleached Acropora table coral on One Tree Island reef, southern Great Barrier Reef. April 2024. Credit: University of Sydney
Bleached Acropora and Porites ] coral at One Tree Island Reef. 2 April 2024. Credit: Maria Byrne/The University of Sydney
Coral at One Tree Island reef in April 2022 before the bleaching event. Credit: The University of Sydney
The University of Sydney's One Tree Island research station on One Tree Island reef on the southern Great Barrier Reef. Credit: The University of Sydney
Senior author Professor Maria Byrne on the Great Barrier Reef. Credit: The University of Sydney