Coral reefs face multiple global and local threats. The combination of global climate change and local threats has resulted in major declines in coral reef ecosystems worldwide. Over 50% of corals may have been lost in the last 30 years, ref and corals are now listed as “most at risk of extinction” by the opens in a new windowConvention on Biological Diversityopens PDF file . ref
This section provides an overview of the major threats affecting coral reefs as well as on the ecological response of corals to these threats. For more in-depth information, take the Coral Reef Resilience Online Course. Read a description of the course or opens in a new windowenroll in the course.