Marine and coastal biodiversity

India's coastline runs for more than 7,500 kilometres, including the island groups, and its marine zone includes coral reefs, mangroves, seagrass beds, estuaries and deep-sea habitats. Mangroves in the Sundarbans, the largest mangrove forest in the world shared with Bangladesh, shelter fish nurseries, protect coasts from storms and store large amounts of carbon in their mud. Coral reefs around the Lakshadweep islands, the Gulf of Mannar and the Gulf of Kachchh support fish, tourism and coastal protection, but bleach when sea temperatures rise.

Marine life faces pressures that land conservation does not: overfishing, destructive fishing gear, plastic and chemical pollution, port and coastal construction, and warming and acidifying seas. Sea turtles, dugongs, sharks and many reef fish are affected, and the loss is often invisible because it happens underwater and far from voters. Marine protected areas exist, but they cover a smaller share of India's seas than protected areas cover on land, and enforcement at sea is harder and more expensive.

Indian law approaches the coast through several instruments rather than one marine law: the Wild Life (Protection) Act, 1972, for protected species and areas; the Coastal Regulation Zone notification, first issued in 1991 and revised since, which regulates construction and activity near the shore; and fisheries rules made by states and the Centre. The Gulf of Mannar Marine National Park and the Sundarbans are among the best-known marine and coastal protected areas, but a list of parks is not a measure of how well fish stocks or reefs are doing.

For coastal communities, the stakes are direct. When a reef dies or a mangrove is cleared, fish catches fall, storm damage rises and tourism income drops. Marine conservation therefore needs fisheries management — closed seasons, gear rules and catch limits that fishers accept — as much as it needs park boundaries.