The Houtman Abrolhos Islands, off Western Australia, where corals appear to be exceptionally heat-tolerant Bill Bachman/Alamy Coral reefs on a chain of islands off Western Australia were almost untouched by a prolonged heatwave that devastated corals in other regions in early 2025. Researchers hope that learning the secret of extreme heat tolerance in these corals will help to protect reefs across the globe, which are in danger of being wiped out by global warming. Kate Quigley at the University of Western Australia in Perth and her colleagues dived at 11 sites across the Houtman Abrolhos archipelago in July 2025. Further north at the Ningaloo Reef, up to 60 per cent of corals died during the same heatwave. This was a story repeated at reefs around the world, with marine heatwaves in 2025 killing vast swathes of coral globally. But at Houtman Abrolhos, apart from a few tiny patches, there weren’t even any signs of stress, such as fluorescing coral. “We expected to see mass bleaching with lots of white colonies, and likely mortality of reefs, given …