A recent global report highlights a significant decline in the coverage of living, hard coral stalks on reefs worldwide. Experts warn that an upcoming powerful El Niño event could exacerbate this trend, with research indicating a rise in the intensity of the natural warming phenomenon. The Status of Coral Reefs of the World 2025 report underscores the impact of marine heatwaves and bleaching events on coral health, leading to a global hard coral coverage of around 25%.
Lead author Manuel González Rivero notes that coral cover was much higher in the 1980s, emphasizing the dwindling recovery window due to more frequent extreme ocean heat events. The report reveals a concerning 9.5% recent decline in coral cover compared to previous decades, signaling substantial losses across most coral reefs globally.
The study by the Global Coral Reef Monitoring Network tracks a clear downward trajectory in hard coral cover since 1980, particularly following global bleaching events caused by elevated ocean temperatures. While corals can recover from bleaching episodes given time, the frequency of such events, including the most recent declared over, poses challenges for their resilience.
Region-specific declines are observed in Australia, the eastern Pacific, the Caribbean, and the area spanning from the Persian Gulf to the Arabian Sea. Despite growth in some regions like the western Indian Ocean, data limitations pre-1998 suggest potential declines in hard coral cover. Enhanced monitoring efforts are urged to provide accurate assessments and understand global reef conditions better.
Efforts to increase coral resilience necessitate global and local interventions to mitigate overfishing, pollution, and coastal development. Experts emphasize the urgent need to curb greenhouse gas emissions to combat climate change, which drives ocean warming and adversely affects coral reefs.
As El Niño events grow stronger, recent research reveals a historical strengthening trend in these phenomena, impacting coral geochemistry. The study underscores the urgency to address climate change to safeguard coral reef ecosystems in the face of escalating environmental challenges.