By analysing samples from the Galápagos Islands, her team found that El Niño episodes in the past 40 years were noticeably stronger than those recorded before 1850.

The finding matches a broader picture of reef decline. The Status of Coral Reefs of the World 2025 report, which examined data from close to 37,000 reef sites, shows a steady drop in hard‑coral cover since 1980, falling to roughly 25 % today from more than 30‑40 % in the 1980s.

Manuel González Rivero, lead author of the report and a scientist with the Australian Institute of Marine Science, notes that this loss is linked to repeated marine heatwaves and bleaching events.

Adding to the stress, scientists expect this year’s El Niño to be record‑breaking. Emily Darling, director of Coral Reefs at the Wildlife Conservation Society, says the already high ocean temperatures now give corals only about nine to twelve months to recover before the next heat spike hits.

Because the recovery window is shrinking, even the most resilient coral species are hit repeatedly, raising concerns about the long‑term survival of reefs worldwide.