Indian Ocean Coral Bleaching
Bleaching Risk Low but Heat Stress Remains
Sea surface temperatures (SSTs) across the Western Indian Ocean have increased again in March–April, returning to the elevated levels observed over the past three years. Despite this, bleaching observations across the region have remained minimal. This may reflect the impacts of significant mortality in 2024, as well as relatively cooler conditions earlier in the year (January–February).
As we approach the end of the bleaching season, marked by the onset of the southeast monsoon winds, overall bleaching risk is now considered low.
For materials and guidance on responding to coral bleaching and mortality, watch the following video or download the following guide. Bleaching alerts from 2009 to date are available further down the page.
Indian Ocean Bleaching observations Dashboard 2016-2025 click to open the dashboard
Report Coral Bleaching
Submit basic observations on coral bleaching through this embedded window, in the google-form below. 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.
HISTORICAL BLEACHING – 2009 TO PRESENT
All past bleaching alerts, from 2009 to the current year, are in the window below. Click on the relevant year, or scroll left/right within each year for additional alerts. Alerts are published between January and May each year, with fewer alerts when bleaching risk is low.