Indian Ocean coral bleaching

16 January 2018 – Given the entire WIO is showing abnormally cool conditions, two cyclones have occurred by mid-January and both ENSO and IOD indicators are neutral, we expect little bleaching in 2018. Most likely southern locations in the WIO will not experience bleaching stress, but it may develop in more northern locations as the season develops..

See the full alert in the pdf at right.

For materials and guidance on responding to coral bleaching and mortality, visit this page.

Bleaching alerts from 2009 to date are available further down the page, and more information is available at these links – background and methods.


Bleaching observations 2017

The map is updated using observations made via the bleaching report form (right), or at this link – Data displayed here is updated periodically to the global bleaching database maintained by the NOAA Coral Reef Watch programme.

Access maps for 2016 coral bleaching and mortality observations.

Report coral bleaching

Submit basic observations on coral bleaching through this embedded window, or go to the google-form at this link. All data will be submitted to the global bleaching form supported by the NOAA Coral Reef Watch programme, and made accessible on a WIO regional database under development.


Alerts are published approximately every two weeks between January and May in each year. Select a year, or use the navigation arrows to move left or right to view individual alerts.