On-Site Monitoring Tools for Coral Bleaching Events

Scientists and researchers around the world are actively responding to coral bleaching events through various initiatives and strategies aimed at understanding, mitigating, and adapting to the impacts of bleaching. Some of the key ways in which organizations are monitoring or tracking coral bleaching events using various on-site methods include:



  • Atlantic Gulf and Rapid Reef Assessment (AGRRA) is a standardized coral reef monitoring protocol in the Wider Caribbean. It includes the bleach watch portal which gathers information from multiple methods such as Bardrop, belt, and point transects.


Mesoamerican Region

  • Healthy Reefs Initiative and 70+ partner surveyors use the ECOMAR Belize Coral Watch Program (Bardrop) and input results into the AGRRA online platform.


Hawaiian Islands

  • Hawaiʻi Coral Bleaching Collaborative (HCBC), established in 2015, conducts multiple methods for tracking coral response and recovery over time by quickly assessing bleaching stress on reefs statewide. The collected data informs scientific understanding and management decisions aimed to reduce coral mortality in Hawaii’s reefs.
  • Koa A Corps involves a color card process which citizen scientists can use to report bleaching in the Hawaiian Islands.
  • Eyes on the Reef Hawai’i involves citizen scientists, which implement an early warning system for coral bleaching, coral disease, Crown-of-Thorns Sea Stars (COTS), and marine invasive species in Hawai‘i.

South Pacific

New Caledonia 

AustraliaGreat Barrier Reef


East Asia 



  • Philippines Coral Bleaching Watch is a citizen science program which serves as an early warning system for documenting coral bleaching data (presence/absence) and Crown-of-Thorns Sea Stars (COTS) outbreaks in the Philippines.


  • Coral Bleaching Network in Indonesia is comprised of a network of organizations and citizen scientists trained using Reef Check to track reef health and bleaching using belt transects.


  • ReefCheck Malaysia involves a network of organizations and citizen scientists trained to track reef health and bleaching using belt transects.

Indian Ocean

Red Sea

  • The Regional Organization for the Conservation of the Environment of the Red Sea and Gulf of Aden (PERSGA) uses the Standard Survey Methods for Key Habitats and Key Species in the Red Sea and Gulf of Aden and monitors coral health including coral bleaching in Djibouti, Egypt, Eritrea, Israel, Jordan, Saudi Arabia, Somalia, Sudan and Yemen.
  • Transnational Red Sea Center is a scientific research center created in 2019 at the Ecole Polytechnique fédérale in Lausanne (EPFL) with the official support of the Swiss Foreign Ministry. An independent and not-for-profit organization has launched an expedition to monitor the health of coral reefs in the Gulf of Aqaba.

The best method will depend on what you can measure, how you measure it, the longevity of the program, and the financial/human resources available! 

If you monitor coral bleaching and would like to be included in this list please contact us: arivera-sosa@coral.org

Additional Resources

New! Education on Coral Bleaching

Coral Identification Support

Continue to Online Apps for Coral Bleaching >

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