Brief Context
A severe mass coral bleaching event described as unprecedented is unfolding off Australias western coast, impacting the Ningaloo Reef, a UNESCO World Heritage site.
Source Content
Syllabus: GS3/ Environment
In News
- A severe mass coral bleaching event described as unprecedented is unfolding off Australia’s western coast, impacting the Ningaloo Reef, a UNESCO World Heritage site.
About
- The event is part of a broader fourth global coral bleaching episode, ongoing since 2023.
- The NOAA reported that nearly 84% of the world’s reef areas have experienced bleaching-level heat stress, impacting over 80 countries and territories.
- The crisis is worsened by rising global sea surface temperatures, overfishing, and pollution—challenges that have intensified due to climate change.
Coral Reefs: Key Facts
- What are Coral Reefs?
- Underwater ecosystems formed by reef-building corals.
- Composed of colonies of coral polyps bound by calcium carbonate.
- Coral polyps live in endosymbiosis with algae (zooxanthellae).
- Favorable Conditions:
- Temperature: 20°C–35°C
- Salinity: 27%–40%
- Depth: Prefer shallow waters (<50 m) for sunlight access
- Major Coral Reefs:
- Global: Great Barrier Reef, Australia (UNESCO World Heritage Site)
- India: Gulf of Kutch, Gulf of Mannar, Andaman & Nicobar Islands, Lakshadweep, and Malvan.
Benefits of Coral Reefs
- Marine biodiversity hotspot & support oceanic food chains
- Coastal protection against storms and erosion
- Carbon sequestration aiding climate mitigation
- Livelihoods and boost to the Blue Economy
- Source of novel medicines (antivirals, anticancer agents).
Threats to Coral Reefs
- Climatic impacts: Bleaching, acidification, algal blooms
- Human Activities: Overfishing, pollution, coral mining
- Habitat Destruction: Coastal development and sedimentation
Way Ahead
- Climate Action: Keep global warming well below 2°C (Paris Agreement)
- Policy & Governance: Enforce SDGs (especially SDG 8 & 12)
- Global Collaboration: Tackle overfishing and marine pollution collectively
- Innovation: Promote R&D in climate-resilient coral species
Source: TH