CORAL BREACH

The government plans a seaweed park in Tamil Nadu, ignoring the threat that Kappaphycus, a widely grown invasive seaweed, poses to corals in the Gulf of Mannar Marine National Park running along the state's coastline

- ROHINI KRISHNAMURTHY

UP CLOSE, a dead coral colony looks ghostly. Corals usually come in shades of green, brown, pink, yellow, red or blue. But a snorkelling investigation of three coral colonies adjoining Kurusadai, one of the 21 uninhabited islands that form the Gulf of Mannar Marine National Park along the Tamil Nadu coastline, shows them to be grey and eerie.

The 21 islands came under the control of the forest department in 1986, which established the national park—a 10,500 sq km reserve that is a habitat for the rare sea cow, dolphin and dozens of coral species—the same year. Being a protected area, tourism was not allowed in the national park until March 2022, when Kurusadai opened its doors to tourists (the other 20 islands are still closed for visitors). The corals, which provide shelter to myriad marine life, protect against storms and support livelihoods through fisheries and tourism, could have been the star attraction. "But they are dead," says S Mahendran, forest range officer at the Mandapam Forest Range in Tamil Nadu's Ramanathapuram district, where the national park is located. One of the prime threats that killed the corals near Kurusadai is Kappaphycus alvarezii, a seaweed (alga) species deliberately introduced in Ramanathapuram for commercial cultivation some two decades ago. The International Union for Conservation of Nature lists it as one of the world's 100 most invasive species.