Global Status of Coral Reefs

Submitted by admin on 5. October 2021 - 17:33

Global Status of Coral Reefs

Report on Status of Coral Reefs
of the World 2020
launched 5 October 2021 by
Global Coral Reef Monitoring Network

Coral reefs occur in more than 100 countries and territories and whilst they cover only 0.2% of the seafloor, they support at least 25% of marine species and underpin the safety, coastal protection, wellbeing, food and economic security of hundreds of millions of people. The value of goods and services provided by coral reefs is estimated at US$2.7 trillion per year, including US$36 billion in coral reef tourism. However, coral reefs are among the most vulnerable ecosystems on the planet to anthropogenic pressures, including global threats from climate change and ocean acidification, and local impacts from land-based pollution such as input of nutrients and sediments from agriculture, marine pollution, and overfishing and destructive fishing practices.

Maintaining the integrity and resilience of coral reef ecosystems is essential for the wellbeing of tropical coastal communities worldwide, and a critical part of the solution for achieving the Sustainable Development Goals under the 2030 Agenda for Sustainable Development.

The Global Coral Reef Monitoring Network (GCRMN) was established as an operational network of the International Coral Reef Initiative (ICRI) in 1995. It aims to provide the best available scientific information on the status and trends of coral reef ecosystems for their conservation and management. The GCRMN is a global network of scientists, managers and organisations that monitor the condition of coral reefs throughout the world. The GCRMN operates through 10 regional nodes.

Its flagship product is the Status of Coral Reefs of the World report that describes the status and trends of coral reefs worldwide. This sixth edition of the GCRMN Status of Coral Reefs of the World report is the first since 2008, and the first based on the quantitative analysis of a global dataset compiled from raw monitoring data contributed by more than 300 members of the network. The global dataset spanned more than 40 years from 1978 to 2019, and consisted of almost 2 million observations from more than 12,000 sites in 73 reef-bearing countries around the world.

The release of this sixth report on 5 October 2021 coincides with key upcoming biodiversity and climate change meetings, namely the 15th meeting of the Conference of the Parties to the UN Convention on Biological Diversity (CBD COP15) and the UN Climate Change Conference (COP26), to provide decision makers with the best available scientific information on the status and trends of coral reef ecosystems for their conservation and management.

The report demonstrates that key indicators of coral reef health and condition, that are recommended by ICRI for inclusion in the new Post-2020 Global Biodiversity Framework, are feasible and provide really important information for decision making.

Key Report Findings

• Around 14% of coral reefs died in a nine-year period between 2009 and 2018 and in the last 10 years, algae on reefs has increased by about 20% - a clear sign of reef stress and decline.

• Coral reefs across the world are under relentless stress from warming and acidification caused by climate change.

• Although the rate and extent of coral decline is severe, there are signs that some coral reefs can recover if left undisturbed. Immediate and drastic action to reduce CO2 emissions will help more coral to recover and survive into the future.

• During the last decade, the interval between mass coral bleaching events has been insufficient to allow coral reefs to recover, although some recovery was observed in 2019 with the world’s coral reefs regaining 2% of the coral cover that was previously lost.

Some information provided at the launching event

Major coral reef bleaching events due to global heating began in 1998 with the loss of 8% of corals around the world. There was a partial recovery in 2002-2010, showing that coral reefs still have some resilience. Further bleaching events in 2010 and 2016 caused a 14% coral loss replaced by 20% more algae. Also a sea surface temperature anomaly since 2011 with prolonged high ocean temperatures has hindered coral recovery, driving further reef decline. Since 2019, there is some possible evidence of coral adaptation to increasing temperatures. There has also been considerable variation between subregions, suggesting that some subregions may be better protected than others against ocean warming.

The report is available at

Sources: and…

Last updated 5 October 2021