Bleaching in the Keppel Islands, Australia. Photo © Paul A. Marshall, Great Barrier Reef Marine Park Authority
Coral reef ecosystems that are more resilient to the impacts of global and local stressors are better able to resist and recover.

Coral reefs face multiple global and local threats. Over the last decade, the percent of threatened reefs has increased by 30%, and global and local stressors currently threaten nearly 75% of the world’s reefs.ref Over the last three decades, bleaching has been reported from virtually every region that supports coral reefs, and no region of the world’s tropical and subtropical seas appears safe from bleaching. ref

This section presents information on the major threats affecting coral reefs as well as on the ecological response of corals to these threats.