A team studying coral reefs off the Houtman Abrolhos Islands in Western Australia found some corals unusually resistant to heat during a historic marine heatwave.

The study, published in Current Biology, calls for immediate greenhouse gas emission reductions and prioritizing protection of refugia to safeguard coral survival.

Indications from the World Meteorological Organization point to a strengthening El Niño, which typically raises regional ocean warming and could worsen coral stress in coming years.

Lead researcher Kate Quigley notes that the resilience may be tied to Abrolhos’ location as a tropical-temperate transition zone, indicating environmental context contributes to coral hardiness.

High performance of specific algae (zooxanthellae) living in coral symbiosis boosts energy supply and contributes to thermal resilience.

The researchers stress urgent climate action to protect remaining resilient reefs and challenge the idea that all corals are doomed, urging ongoing conservation efforts.

The study identified that only about 10 reefs worldwide have shown the ability to resist heat stress events like last year’s, signaling rare resilience among corals at Abrolhos.

Led by Dr. Kate Quigley, a multi-institution team conducted field and lab work during the peak heatwave and found Abrolhos corals unusually tough compared with other reefs.

Findings point to the existence of coral refugia—areas that stay healthy despite warming oceans—likely numbering fewer than ten globally, underscoring the need to protect these zones.

Researchers suggest the transitional zone between tropical and temperate waters may explain the observed resilience, though more studies are needed.

Scientists describe these resilient reefs as possible refugia in a warming world and urge protecting these areas while rapidly cutting greenhouse gas emissions to safeguard their survival.

A key factor appears to be the performance of certain symbiotic algae that supply energy to corals, potentially enabling greater thermal tolerance.