Lizard Island coral death reaches 92 per cent after 2024 bleaching event, study finds

Last year’s bleaching was part of a global marine heatwave that hit tropical reefs across the planet

Almost all of the surveyed coral at Lizard Island on the Great Barrier Reef died after last year’s bleaching event, a new study found, revealing one of the highest coral mortality rates ever recorded anywhere in the world.

The 2024 bleaching was part of a global marine heatwave that hit tropical reefs across the planet. Even though Lizard Island did not experience the most extreme temperatures, the coral death rate was still “unprecedented”, researchers noted.

“These results highlight the fragility of coral ecosystems facing increasing stress from climate change, and the possible devastation resulting from the 2024 global bleaching event,” study lead author Dr Vincent Raoult of Griffith University explained.

The study team used drone surveys and in-water observations to monitor 20 reef sections at the island’s northern and southern ends. Bleaching had affected an average of 96 per cent of living coral.

By June, after peak heat stress, mortality had reached 92 per cent, with some areas seeing losses of more than 99 per cent.

Cover photo:  Nearly 97 per cent of coral reported dead on northern Great Barrier Reef