Source: Rising temperatures trigger widespread coral bleaching in Gulf of Mannar & Palk Bay (Down To Earth, May 24, 2024)
The Gulf of Mannar and Palk Bay, nestled along India’s southeast coast, have long been renowned for their vibrant coral ecosystems. However, recent events have cast a shadow over these underwater marvels as coral bleaching and die-offs, reminiscent of crises seen in the Great Barrier Reef, threaten their existence.
These phenomena, exacerbated by the warming effects of El Nino, underscore the urgent need to understand and address the environmental challenges facing these delicate marine habitats.
A Threatening Trend
- Gulf of Mannar and Palk Bay, near India’s southeast coast, are rich coral hotspots.
- Recent coral bleaching and die-offs resemble those in Australia’s Great Barrier Reef.
- El Nino effect, causing increased sea surface temperatures, is the primary cause.
Impact of Environmental Changes on Corals
- Corals, highly sensitive to temperature fluctuations, suffer due to rising atmospheric and sea surface temperatures.
- Sustained temperature increases lead to coral bleaching, endangering reefs globally.
Challenges Faced by Coral Reefs
- Corals survive bleaching events but are stressed and face mortality.
- Since 1998, Gulf of Mannar and Palk Bay reefs have experienced severe bleaching events.
Threats to Gulf of Mannar Coral Reefs
- Gulf of Mannar comprises 21 islands, facing threats like pollution, sedimentation, destructive fishing, and biological invasion.
- Overfishing and anthropogenic pressures worsen the situation, leading to seaweed dominance.
Current Status and Future Outlook
- Major bleaching events occurred in 1998, 2010, 2016, and 2024, indicating a global pattern.
- Overfishing and human activities severely impact Gulf of Mannar reefs, slowing coral growth.
- Despite challenges, Palk Bay reefs remain relatively better.
- Global estimates suggest significant damage to coral reefs, with potential further loss by 2030.
Also Read | Protecting The Rainforests Of The Sea: Coral Reefs
Gulf Of Mannar And Palk Bay
The Gulf of Mannar and Palk Bay are located along India’s southeastern coast, bordering Sri Lanka . They are renowned for their vibrant coral ecosystems, critical marine habitats that shelter a diverse array of species.
Gulf of Mannar:
- A large, shallow bay forming part of the Laccadive Sea in the Indian Ocean.
- Separated from Palk Bay by Adam’s Bridge/Rama Setu, a chain of islands and reefs.
- Average depth of around 19 feet (5.8 meters).
- Notified marine national park in India.
Palk Bay:
- Located north of the Gulf of Mannar, between India and Sri Lanka.
- Width varies from 36 to 67 miles (57 to 107 kilometers) and length is around 93 miles (150 kilometers).
- One of the major sinks for sediments along with the Gulf of Mannar.
Environmental Threats:
These ecosystems face threats from:
- Climate change, particularly rising sea temperatures that can cause coral bleaching and death.
- Overfishing, which disrupts the delicate balance of the reef ecosystem.
- Pollution from coastal development and agricultural runoff.
- Destructive fishing practices like bottom trawling that damage the reef structure.
Conservation Efforts:
- The Gulf of Mannar Biosphere Reserve, established in 1989, protects a portion of the gulf’s marine environment.
- Marine protected areas have been established in both the Gulf of Mannar and Palk Bay to restrict fishing and other activities that harm the reefs.
- Efforts are underway to promote sustainable fishing practices and reduce pollution in the region.