MSC Cruises has announced that an MSC Foundation-supported report, drawing on more than 21 million observations, warns that marine heatwaves are reducing the time reefs have to recover.
The report is the largest global assessment of coral reef condition ever produced by the Global Coral Reef Monitoring Network (GCRMN).
It reveals the scale of the declining coral reef cover worldwide and highlights the importance of science-based conservation and long-term monitoring to help reefs recover and build resilience.
“We are proud to have contributed to this extraordinary global scientific effort,” said Daniela Picco, executive director of the MSC Foundation.
“Coral reefs are sending us a clear message: these vital ecosystems are under increasing pressure worldwide. Yet the report also shows that where local stressors are managed effectively, reefs can recover,” added Picco.
“This is why we strongly believe in the importance of investing in research and monitoring, which helps inform restoration locally.”
“This report provides the most comprehensive assessment to date of the status of the world’s coral reefs,” said Dr Manuel Gonzalez Rivero, lead author of the report.
“The strongest pathway to safeguard coral reefs is rapid emissions reductions, effective action on local pressures and sustained long-term monitoring so action is targeted where it matters most,” added Rivero.
According to MSC, coral reefs cover only 0.2 percent of the ocean floor, but they are home to more than 25 percent of all marine species. The report shows a relative decline of 9.5 percent compared to the baseline average for 1980-2009, with the steepest losses following mass bleaching events driven by marine heatwaves.
Despite the global decline, several regions show that reefs can recover when local threats are managed effectively. This provides an important message for policymakers and reef managers: well-designed local action can make a measurable difference.
MSC said in a press release that the report shows the Caribbean has shown a strong decline in coral cover, especially following strong marine heatwaves and disease outbreaks.
The 2025 GCRMN assessment draws on 40 years of global data, bringing together 21,1 million observations from 36,886 reef sites, more than 10 times the number included in the 2020 report. More than 600 partners worldwide collated the data across many reef monitoring networks.
The full report is available here.
