Large expanses of placid water, fishing boats plying quietly on their daily rounds, and flocks of flamingos wading through the shallows. On the exposed banks of the lake are more birds: Eurasian curlews, oystercatchers, and bar-tailed godwits, which have flown in from Europe and Siberia to trade their harsh winters for the warmth of the tropics.
These are some of the scenes at Pulicat Lake, a brackish water lagoon which lies on the border of southern Andhra Pradesh and north Tamil Nadu, just 60 kilometres north of Chennai. Apart from being an important bird habitat, the lake is also a crucial source of livelihood for hundreds of fisherfolk who depend on its resources.
Spread over around 60,000 hectares, Pulicat Lake is a bird haven. The wetland is one of 467 Important Bird Areas in India, identified by the Bombay Natural History Society and Birdlife International in 2004. More than 220 bird species thrive in this wetland, across seasons, as per data on eBird, an open-access citizen science initiative. A part of the wetland is also designated the Pulicat Bird Sanctuary.
Among the birds that use the Pulicat wetland are almost 60 migratory bird species — including graceful greater flamingos and rare ruddy turnstones — that fly in from as far as Europe and Siberia, says writer and naturalist M Yuvan who has been observing birds in Pulicat for more than a decade. These birds are attracted to Pulicat’s biggest treasure, its rich hunting grounds. The shallow, brackish waters here teem with shrimp and a huge diversity of marine life. Several species of guitarfish and sawfish which can survive only in such brackish habitats (and are undergoing population decline in many parts of the world) still thrive here, according to marine biologist Divya Karnad from Ashoka University. Mangroves trees and vegetation that are specially adapted to thriving in these partly salty waters, also fringe the lake. The intricate root networks of these trees are important microhabitats and nurseries for small fish. In fact, the Ministry of Environment, Forests and Climate Change (MOEFCC) lists Pulicat as one of Tamil Nadu’s five major mangrove areas.
These marine riches make Pulicat a coveted resource for people too. Fisherfolk in the villages located along the periphery of the lake depend on the waterbody for their livelihoods. Karnad notes how people here still practise the ancient padu system, a form of traditional fishery management wherein villagers mutually decide on access to rich fishing grounds. The resources of Pulicat also attract people from far away, says writer and activist Nityanand Jayaraman of the Vettiver Collective. Several Scheduled Caste and Tribe communities including the Irulars and Yanadis — “people from very poor sections with very little in terms of government recognition”, says Jayaraman — depend solely on Pulicat to eke out a living from fishing and allied activities.
What makes Pulicat such a crucial resource for both people and wildlife is a single strip of sand: Kattupalli Island. Kattupalli is a sparsely inhabited, 25-km-long sand barrier island located at the mouth of Pulicat lagoon. This linear island lies just north of Chennai, with the Bay of Bengal on its east and the Kosasthalaiar and Karungali rivers (that separate it from the mainland) on the west. It is the only thing that stands between the vast ocean and Pulicat lagoon. If the island disappears, the ocean and Pulicat would merge. The brackish water ecosystem — which has higher salt levels than freshwater, but not as much as the sea — would vanish. Pulicat would die. This scenario may sound almost fictional. How can an entire island disappear? But erosion — caused by wave action that occurs when coastlines are altered, and the resulting changes in sand movement along the shore (a process called long-shore drift) — is already a worry in Kattupalli. Furthermore, environmentalists are also concerned that a proposed port in the area could accelerate this process. If the barrier island breaches, entire villages will be lost, says Jayaraman.
Biologists too fear the erosion of the Kattupalli Island. Pulicat opening up directly to the ocean would be a death knell for wildlife (such as guitarfish) that can survive only in such habitats, says Karnad. It could also mean the end of one of India’s only sustainable shrimp fisheries, she cautioned. Pulicat is a natural shrimp farm that requires no tending to. Ecologically damaging bottom-trawling isn’t a necessity here to harvest shrimp either: fisherfolk merely catch them by hand.
The water resources of Pulicat Lake are also what maintain the groundwater levels in north Chennai, adds Karnad. This, along with the diversity of life that the lake sustains, makes it a very important habitat for both wildlife and people.