The National Institute of Oceanography has announced plans to translocate 18 coral colonies from the Mumbai coast. This operation is part of an initiative for the progressing Mumbai Coastal Road Project.
Understanding Corals
Contrary to certain beliefs, corals are not plants but oceanic creatures, related closely to jellyfish and anemones. They consist of genetically identical organisms named polyps; small, soft-bodied organisms with a protective limestone skeleton at their base known as a calicle. These calicles collectively form the structure of coral reefs.
The Symbiotic Relation: Corals and Zooxanthellae
Corals house within them microscopic algae called zooxanthellae contributing to a symbiotic relationship. The coral offers zooxanthellae the required compounds for photosynthesis, and in exchange, the algae supply the coral with organic photosynthesis products like carbohydrates. These carbohydrates enable the coral polyps to create their calcium carbonate skeletons.
Types of Corals
There exist two types of corals. The first, stony, shallow-water corals, are responsible for reef building. The second type includes soft corals and deep-water corals that inhabit dark, cold waters.
Formation of Coral Reefs
Reefs come into existence when a polyp attaches itself to a seafloor rock, then divides or buds into thousands of clones. The polyp calicles connect to one another, forming a colony functioning as one organism. Over time, these colonies grow and join with others, eventually becoming reefs.
Role and Importance of Coral Reefs
Coral reefs, although covering less than 1% of the ocean floor, are one of the most productive and diverse ecosystems on Earth. They are compared to rainforests concerning their biodiversity. Functioning as underwater cities, coral reefs support marine life and are crucial for global food security and livelihoods, directly impacting at least half a billion people worldwide.
Protection and Threats
In India, coral reefs are protected under Schedule I of the Wildlife Protection Act (WPA) of 1972. However, they are threatened significantly by climate change causing “bleaching” of corals.
Coral Bleaching
Coral bleaching is a process where warm weather prompts stressed corals to expel the algae giving them their colors. The Great Barrier Reef, a UNESCO World Heritage site home to one of the largest collections of coral reef, has experienced six mass bleaching events.
Biorock Technology
Biorock technology is a practical method to restore coral reefs using biorock or mineral accretion. The technology applies low-voltage electric currents through seawater, causing dissolved minerals to crystallize on structures.
Coral Translocation
Translocation, still in its infancy along the Indian coastline, is a complex and largely unsuccessful process in India thus far. Pilot projects have been conducted in several sites, like Lakshadweep islands and Andaman islands, to study the survival rate, method and site of translocation.