Chilika Lake

Chilika lies along Odisha’s Bay of Bengal coast, across parts of Puri, Khurda and Ganjam districts. UNESCO’s Tentative List description characterizes it as a shallow, brackish lagoon with estuarine features, connected to the sea through an inlet and separated from it along much of its coast by a sandy barrier. Freshwater enters from rivers and rivulets, while tidal exchange brings seawater into the lagoon. The relative influence of these sources varies across the lagoon and over time, creating a mosaic of salinity and habitat conditions. The lagoon’s area also changes seasonally, so any single surface-area figure should be understood in relation to the season and measurement method.

The mix of freshwater, brackish and marine conditions supports diverse aquatic and wetland life. Chilika is an important wintering area for migratory waterbirds, and Nalabana Island within the lagoon is a designated bird sanctuary. The lagoon also supports Irrawaddy dolphins (Orcaella brevirostris), a threatened coastal dolphin. A peer-reviewed study of Chilika fishers and dolphins found that local fishers’ views of dolphins reflected ecological, economic and cultural relationships; in the study’s observations, dolphin foraging at stake nets was associated with higher catch per unit effort and catch income for a locally preferred fish. Fisheries and other lagoon resources support communities living around and within the lagoon, making ecological management inseparable from livelihoods.

Chilika was added to the Ramsar List of Wetlands of International Importance in 1981. In the decades that followed, siltation and changes to the inlet and sea connection were associated with reduced tidal exchange, shifts in salinity, freshwater weed expansion and declining fishery productivity. The Ramsar Convention’s account says that the site was placed on the Montreux Record in 1993 because of changes in its ecological character. The Montreux Record identifies Ramsar sites where changes in ecological character have occurred, are occurring or are likely to occur; it is a management tool rather than a separate designation of the wetland itself.

The Chilika Development Authority was established in 1992 to coordinate restoration and management. Following hydrological studies, an artificial sea mouth was opened on 23 September 2000 and the lead channel was desilted, aiming to improve exchange between the lagoon and the Bay of Bengal. The Authority’s account describes monitoring by the National Institute of Oceanography before and after the intervention, as well as catchment treatment, bird-habitat work and community involvement. The Ramsar Convention reports that Chilika was removed from the Montreux Record in November 2002 after restoration measures and monitoring, and that the Chilika Development Authority received the Ramsar Wetland Conservation Award in 2002. These interventions are a notable restoration case, but they do not remove the need for continued monitoring, adaptive management and attention to local resource use.

Chilika is designated as a Ramsar wetland, and the Indian government submitted it to UNESCO’s Tentative List in 2014 as a natural property. A Tentative List submission is a proposal for possible future nomination; it does not mean that the site is inscribed on the World Heritage List. Its conservation importance stems from its ecological connections among freshwater, brackish and marine environments, its role for migratory birds and dolphins, and the livelihoods that depend on its productivity. Management must therefore consider hydrology and habitat alongside fisheries, community participation and the effects of development in the catchment and coastal zone.