Reefs at Risk Revisited

n More than 60 percent of the world’s reefs are under immediate and direct threat from local sources—such as overfishing, destructive fishing, coastal development, watershed-based pollution, or marine-based pollution and damage (see map inside front cover). n Approximately 75 percent of the world’s coral reefs are rated as threatened when local threats are combined with thermal stress. This reflects the recent impacts of rising ocean temperatures, linked to the widespread weakening and mortality of corals due to mass coral bleaching (figure ES-1, column 6).