Coral Reefs in India

Coral reefs are spectacular and diverse underwater ecosystems harbouring nearly 25% of all marine species on just 0.1% of ocean area globally. Often called ‘rainforests of the seas’, they serve vital ecological, economic and cultural roles. India is blessed with coral formations along the coasts of the Andaman & Nicobar Islands, the Gulf of Kachchh, the Gulf of Mannar and Lakshadweep Islands, covering around 2,375 sq km area. However, current assessments indicate extensive degradation, necessitating their conservation before coral communities disappear permanently.

Conditions Required for Healthy Growth of Coral Reef

Coral reefs are huge deposits made up dead shells and secretions of marine organisms like Corals, Calcarious algae, stomatopteroids, gartopods Mollusca etc. The deposits are mostly made up of Calcium Carbonate. Conditions required for their growth:

• Warm tropical oceans located between 30 degree north and 25 degree south latitudes where a minimum temperature of 20 degree is found and this temperature favour the growth of coral organisms.
• Oceanic water free of sedimentation.
• Transparent parts of ocean bodies.
• Relatively low salinity ocean bodies.

The reefs at present are important to the local community only to the extent of sustenance fishing. Tourism is being developed at some places though local communities do not benefit much from the revenue generated. The health of corals, as deduced from the literature records since 60s has been on steady decline mainly due to stress from anthropogenic pressures and interference.

Distribution and Types

Live coral cover is found along four major regions in India – Andaman & Nicobar Islands, Gujarat state, Tamil Nadu and Lakshadweep islands. The Andaman group, situated in the eastern Bay of Bengal has the most extensive reef formations covering 1,800-1,950 sq km. Here both hard and soft corals encompassing altogether 206 species exist, the richest coral diversity in India.

The Gulf of Kachchh along Gujarat’s Saurashtra coastline harbours patchy coral growths over 415 sq km where 42 species have been recorded. Tamil Nadu’s Gulf of Mannar Biosphere Reserve has 117 hard coral species recorded within a 60 km stretch where reefs occupy around 36 sq km, already showing signs of degradation. Finally, serene Lakshadweep, the pristine tiny coral islands on India’s western shelf area possess around 20-30 sq km of living coral colonies belonging to 55 species. Overall, India accounts for nearly 2.1% of the world’s coral cover.

Challenges and Threats

Multiple threats jeopardize the future of India’s coral reefs. Coral mining, destructive fishing practices like dynamite fishing that damage reef structure and pollution from ships and land have induced alarming declines recently. Corals are highly sensitive to temperature changes and increased sediment loads from coastal activities. Dynamite fishing in particular has converted complex reefs into rubble zones around many coastal villages. Corals also suffer due to weed infestation and crown-of-thorns starfish attacks in current times.

Climate change poses grave concerns going ahead through coral bleaching events due to warming seas, amplified storm activity and ocean acidification impeding coral growth. Tourism expansion and proposed dredging under pork and port development plans further imperil these ecosystems. Reefs around urban centers like Mumbai, Chennai and the Andamans need urgent attention and restoration efforts before their condition deteriorates irreversibly.

Conservation Efforts

Recognizing their environmental significance, India has prioritized coral reef conservation and management through establishing marine parks and sanctuaries for protecting fragile island and coastal ecosystems. The Gulf of Mannar Marine National Park, Malvan Marine Sanctuary and various protected areas in the Andaman and Nicobar as well Lakshadweep islands harbour coral reefs requiring stringent safeguarding. Authorities conduct periodic coral transplantation programs, attempting to rejuvenate degraded reef areas. Coastal Regulation Zone laws aim to regulate developmental activities around India’s sensitive coastal and island zones.