Great Barrier Reef — 2024–2025 Consecutive Mass Bleaching Events
Recent Developments
012025: AIMS confirmed a sixth mass bleaching event on the Great Barrier Reef, the second consecutive-year bleaching sequence on record for the Reef (2024–2025).
02May 2025: AIMS reported aerial surveys over 281 reefs in the Torres Strait, northern Great Barrier Reef, and parts of the central region found widespread bleaching, with severe impacts concentrated in northern areas.
03December 2025: NOAA reported the ongoing fourth global coral bleaching event had affected about 84.4% of the world’s coral reef area and documented mass bleaching in at least 83 countries and territories.
Interventions
- AIMS and the Great Barrier Reef Marine Park Authority are conducting reef-health monitoring and aerial surveys to track bleaching extent and coral condition.
- NOAA Coral Reef Watch is monitoring global heat stress and providing bleaching alerts and status updates for reef managers worldwide.
- The Great Barrier Reef Foundation is publishing threat assessments and supporting reef resilience and restoration efforts.
What Works
- Reducing local stressors such as poor water quality and sediment runoff can improve coral resilience to heat stress; the Reef Foundation notes that bleaching is primarily driven by elevated ocean temperatures, but water quality and other stressors also contribute.
- Early detection and rapid response monitoring help managers identify heat-stressed reefs and prioritize conservation measures; AIMS and NOAA both use repeated aerial/satellite monitoring to guide response.
- Global emissions reductions are the only durable solution to the primary driver of mass bleaching, which is rising ocean temperature from climate change.
How to Help
- Support credible reef conservation and research organizations such as the Great Barrier Reef Foundation, AIMS-affiliated programs, and the Australian Marine Conservation Society.
- Advocate for climate action and stronger reef-protection policy to reduce the ocean warming that drives bleaching.
- Reduce personal emissions and support policies that lower greenhouse-gas pollution, since climate-driven heat stress is the main cause of bleaching.
Make an Impact
Donate directly to 5 verified organizations working on this crisis. Every contribution makes a difference.
Donate to Organizations ↓Coming soon: one-click donations distributed across all organizations via our impact protocol.
Raise Awareness
Can't donate? You can still make a huge impact. Join others in amplifying this cause globally by sharing it with your network.
Verified Organizations
Organizations Helping(17)
The Great Reef Census engages volunteers worldwide to identify and label coral reef images, providing critical data for scientists and reef managers. This data helps monitor reef health and informs conservation strategies. The initiative also expands internationally, partnering with local organizations to empower communities in reef protection.
The Foundation pioneers large-scale coral restoration using advanced technology, including growing heat-tolerant coral larvae in micro-nurseries and deploying them to vital reefs. They focus on restoring 50 key reefs by 2031 and expanding globally. Their programs include the Reef Restoration and Adaptation Program (RRAP) and community-led conservation, integrating Indigenous knowledge and sustainable financing to scale restoration efforts.
CORAL implements a strategic plan (2025-2030) that emphasizes strengthening local communities, leveraging cutting-edge science, and building global alliances to enhance reef resilience. Their approach includes supporting local leadership in reef regions, applying scientific research to conservation practices, and fostering collaborative efforts to address climate change and other threats to coral reefs.
