Chilika Lake - Ecology and Economy

Biodiversity Hotspot

Chilika Lake is one of the most biodiverse wetlands in India, supporting an extraordinary array of flora and fauna. The lake hosts over 225 species of fish, 158 species of phytoplankton, 720 species of non-aquatic plants, and more than 720 species of animals comprising fishes, prawns, crabs, dolphins, birds, and reptiles. The submerged aquatic vegetation, particularly seagrasses of the genera Halodule, Halophila, and Ruppia, forms the base of the food chain, supporting the rich fishery and acting as feeding grounds for migratory waterfowl. The lake also supports the largest population of the endangered Irrawaddy dolphin (Orcaella brevirostris) in any single lagoon of the world, with an estimated 150-170 individuals. The dolphin population has shown encouraging recovery since the opening of the new mouth in 2000, which improved the hydrological conditions and fish availability.

Avian Diversity and Migration

Chilika is one of the most important wintering grounds for migratory birds in the Indian subcontinent. Each year, between October and March, the lake hosts over one million birds belonging to nearly 230 species, including visitors from as far as Siberia, Central Asia, Iran, and the Himalayas. The Nalbana Island, a designated bird sanctuary within the lake, becomes a spectacular congregation site during this period. Notable species include greater flamingos, lesser flamingos, Northern pintails, Eurasian wigeons, black-tailed godwits, bar-headed geese, and numerous species of sandpipers and plovers. The lake lies on the Central Asian Flyway, one of the most important migratory bird routes in the world. Bird counts conducted annually by the Chilika Wildlife Division in coordination with organisations like the Bombay Natural History Society have recorded a general increase in bird populations following the hydrological restoration efforts.

Fisheries and Livelihoods

The fishery of Chilika Lake directly supports the livelihoods of over 2 lakh fisherfolk living in more than 150 villages around the lake. The annual fish landing from the lake ranges from 12,000 to 16,000 metric tonnes, representing the single most important source of fish in Odisha. Major commercially important species include mullets, milkfish, catfish, prawns (including the prized tiger prawn), and crabs. Traditional fishing communities use a variety of gear appropriate to different ecological zones of the lake — gill nets, drag nets, cast nets, and bamboo stake nets being common. The Chilika Development Authority (CDA), established in 1992, manages the lake’s resources and has implemented several fisher-friendly policies including seasonal fishing bans to allow breeding and restricting mechanised fishing in certain zones. The export of tiger prawns from Chilika earns valuable foreign exchange.

Tourism and Economic Activities

Chilika has become one of Odisha’s premier tourist destinations, attracting visitors for its scenic beauty, birdwatching opportunities, dolphin sightings, and the Kalijai Temple — an important pilgrimage site situated on an island. Boat tourism has flourished, with Satapada, Barkul, and Rambha serving as the main access points. The Government operates ferries and encourages private boat operators, providing employment to hundreds. Eco-tourism initiatives, including nature camps and guided birdwatching tours, have been promoted by the CDA. The lake also supports ancillary economic activities such as mat weaving from reeds, lime-shell collection, and salt production in the drier fringes. Tourism revenue complements the fishery-based economy, providing a degree of diversification that helps communities cope with seasonal variations in fish catch.

Conservation Challenges

Despite its ecological and economic importance, Chilika faces several conservation challenges. Siltation from the Mahanadi distributaries, particularly the Daya and Bhargavi, continues to reduce water depth and alter the ecological balance. Illegal prawn culture ponds in the lake’s periphery have encroached on ecologically sensitive areas. Overfishing, use of nets with small mesh sizes, and poaching of migratory birds remain persistent problems. Pollution from agricultural runoff carrying fertilisers and pesticides has led to localised eutrophication in the northern sector. Climate change poses long-term threats through sea-level rise and increased cyclone intensity. The CDA, in partnership with international organisations like the Ramsar Secretariat, Wetlands International, and the Japan International Cooperation Agency (JICA), continues to implement conservation and management interventions, including a regular hydrological and ecological monitoring programme.