The Great Barrier Reef is at risk of “collapse”, scientists warn

Often considered the largest living structure in the world, this coral formation stretches 2,300 kilometers along the northeast coast of the Australian state of Queensland and is one of its main tourist attractions.

This month it was prevented from being classified as “in danger of extinction”, despite the fact that the United Nations expressed its “utmost concern” about its mass bleaching and the impact of climate change.

Morgan Pratchett, a marine conservation ecologist at James Cook University in Queensland, said at the International Coral Reef Symposium in Auckland, New Zealand, that an “extreme El Niño” is a significant concern.

“It is not impossible that the next major disturbance will cause localized species extinctions (…) and widespread ecosystem collapse,” Pratchett said.

This year’s El Niño is expected to break records in its overall intensity, as it will raise surface temperatures in the central and eastern equatorial Pacific.

This in turn will cause changes in global wind, pressure and precipitation patterns.

“It is very likely that we will see large-scale, high-severity mass bleaching on the Great Barrier Reef,” Pratchett said.

UNESCO has been monitoring the reef annually since 2021, when it warned that it was at risk of being included on the list of “in danger” World Heritage sites.

Hard coral cover across the reef decreased substantially between 2024 and 2025. Additionally, above-average water temperatures caused the reef’s sixth episode of mass coral bleaching since 2016.

Professor of Marine Studies Ove Hoegh-Guldberg, from the University of Queensland, said a lack of government action has endangered the future of coral reefs around the world.

“This could be the prelude to the demise of humanity”, he stated.

“If you were on a big ship, like the Titanic, and someone came up to you and told you that the ship was sinking, you would undoubtedly get on one of those lifeboats and start acting and doing something,” he warned.

“We are not doing that. The ship is starting to sink in a really massive way, and we are not seeing it for what it is. It is very serious,” he considered.