Depleting Coral Cover in Lakshadweep

• 31 Jul 2025

For Prelims: Coral Reefs, Coral Bleaching, Marine Heatwaves, El Nino, Algal Bloom, Biorock Technology, Mangroves, Seagrasses, Marine Protected Areas

For Mains: About coral reefs and coral bleaching, Causes of coral bleaching and its implications, Strategies needed to preserve coral reefs. 

Source: TH 

Why in News? 

A study tracking coral health at three major atolls —Agatti, Kadmat, and Kavaratti—has revealed alarming findings, showing a 50% decline in coral cover in the Lakshadweep reefs, from 37.24% in 1998 to 19.6% in 2022. 

What are the Key Findings of the Study on Coral Reefs? 

• Drastic Decline in Coral Cover: Repeated marine heatwaves triggered by El Nino events in 1998, 2010, and 2016, along with climate change, are the main drivers of coral loss.  
  • These stressors have slowed reef recovery, with improvement only after over six consecutive years without coral bleaching. 
• Distinct Coral Response Clusters: Corals displayed six distinct response patterns based on heatwaves impact, recovery rate, depth, and wave exposure.  
  • While local efforts like coral gardening aid restoration, only global emission cuts can provide the critical recovery time reefs need to survive. 

 

What are the Key Reasons for the Depletion of Coral Reefs? 

• Rising Sea Temperatures: Marine heatwaves disrupt the symbiotic relationship between corals and algae, leading to bleaching. Climate change and El Nino events are intensifying ocean warming, making bleaching more frequent and severe. 
  • High UV radiation and thermal stress worsen coral heat stress and increase vulnerability to infections like white band disease, raising the risk of future bleaching. 
• Ocean Acidification: Increased CO₂ absorption by oceans leads to lower pH levels, which weakens coral skeletons and slows their growth.  
  • This hampers corals’ ability to form calcium carbonate structures, making them more susceptible to bleaching. 
• Pollution & Runoff: Agricultural and urban runoff containing fertilizers and sewage promotes algal blooms that smother corals. Sedimentation from coastal development blocks sunlight, depriving corals of essential energy for survival. 
• Human Activities: Destructive fishing methods such as dynamite or cyanide cause direct coral mortality, while tourism activities like anchoring and snorkeling/diving also contribute to coral damage. 

What are the Implications of Coral Depletion? 

• Loss of Marine Biodiversity: Coral reefs support 25% of marine life, but bleaching-driven coral death threatens ecosystems, causing fish population declines, species extinction, and marine food web disruption. 
• Economic Consequences: Reef collapse can reduce fish stocks, endangering the reef fishery industry and global seafood security.  
  • Bleaching also hurts tourism, leading to job losses and economic decline in coastal communities reliant on reef-based activities. 
• Reduced Coastal Protection: Coral reefs serve as natural barriers, shielding coastlines from erosion, storm surges, and flooding.  
  • Without them, coastal communities, especially in low-lying regions like the Lakshadweep and Maldives, face greater risk from hurricanes, sea-level rise, and costly artificial defenses. 
• Decline in Scientific Discoveries: Coral reefs offer potential medicines for diseases like cancer and arthritis, but bleaching destroys unexplored species, limiting future medical discoveries. 
• Water Quality and Climate Regulation: Coral reefs function as natural water filters, with organisms like sponges removing toxins and supporting photosynthetic plants that absorb CO₂ and release oxygen.  
  • When reefs die, these functions are lost, leading to poor water quality, algal blooms, and weakened ocean carbon cycling. 

What are the Various Initiatives to Protect Coral Reefs? 

• International Coral Reef Initiative (ICRI): It is a global partnership of nations and organizations dedicated to the conservation of coral reefs and related ecosystems.  
• Global Fund for Coral Reefs (GFCR): It is a blended finance platform that mobilizes grants and private capital to protect and restore coral reefs and support dependent communities.  
  • It brings together UN agencies, governments, philanthropies, investors, and others to advance ecological, social, and economic resilience. 
• Technological Interventions: 
  • Biorock Technology: Biorock technology is an innovative mineral accretion method that creates natural building structures underwater, aiding in coral restoration (e.g., in the Gulf of Kachchh). 
  • Super corals: They are developed through ex-situ breeding using human-assisted evolution to enhance resistance to high temperatures. 
  • Frozen Coral: Scientists have used cryomesh technology to freeze and preserve coral larvae more effectively, allowing storage at -196°C for long-term conservation. 

What Measures Can be Taken to Protect Coral Reefs? 

• Tackle Climate Change: To curb ocean warming and acidification, reduce carbon emissions by shifting to renewable energy sources, in line with the 1.5°C target set by the Paris Agreement.  
  • Secure international funding (e.g., Green Climate Fund) and expand clean technology access; protect blue carbon ecosystems like mangroves, seagrasses, and salt marshes to absorb CO₂ and shield coral reefs 
• Reduce Local Stressors: Curb pollution by reducing agricultural runoff and improving wastewater treatment to protect reefs from algal blooms and contamination.  
  • Ban destructive fishing, enforce marine protected areas, and regulate coastal development by restricting dredging, and mining along coasts. 
• Active Reef Restoration: Grow and transplant heat-resistant corals, deploy reef balls or 3D-printed habitats, and develop super-corals to survive rising temperatures. 
• Community-Led Conservation: Promote eco-tourism by training local guides in reef-safe snorkeling/diving practices and encouraging reef-friendly sunscreen use.  
  • Support alternative livelihoods like aquaculture and reef monitoring to reduce fishing pressure. 

Conclusion 

The Lakshadweep coral study highlights a 50% decline in reefs due to climate-driven heatwaves, stressing the need for global emission cuts alongside local restoration. Without urgent action, reefs face collapse, threatening biodiversity, coastal economies, and climate resilience. Solutions like Marine Protected Areas (MPAs), super-corals, and pollution control must scale up to avert irreversible loss. 

Drishti Mains Question:

How does climate change impact coral reef ecosystems? Suggest suitable mitigation strategies. 

UPSC Civil Services Examination, Previous Year Question (PYQ)  

Prelims

Q. Consider the following statements: (2018)

1. Most of the world’s coral reefs are in tropical waters.  
2. More than one-third of the world’s coral reefs are located in the territories of Australia, Indonesia and Philippines.  
3. Coral reefs host far more number of animal phyla than those hosted by tropical rainforests. 

Which of the statements given above is/are correct?

(a) 1 and 2 only  

(b) 3 only  

(c) 1 and 3 only  

(d) 1, 2 and 3 

Ans: (d)

Q. Which of the following have coral reefs? (2014)

1. Andaman and Nicobar Islands  
2. Gulf of Kachchh  
3. Gulf of Mannar  
4. Sunderbans  

Select the correct answer using the code given below:

(a) 1, 2 and 3 only  

(b) 2 and 4 only  

(c) 1 and 3 only  

(d) 1, 2, 3 and 4  

Ans: (a)

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Mains

Q. Assess the impact of global warming on the coral life system with examples. (2019)