Chilika Lake Came Off the Ramsar Montreux Record on 11 November 2002 After a New Sea Mouth Took Fish Landings From About 1,600 Tonnes a Year to 14,053 Tonnes, and in January 2026 It Held 11,32,200 Birds and 159 Irrawaddy Dolphins

Chilika Lake, a brackish lagoon on the coast of Odisha, came off the Ramsar Convention’s Montreux Record on 11 November 2002, nine years after it was added. The record is the convention’s register of listed wetlands whose ecological character has changed. The lake left it after a new mouth to the Bay of Bengal restored its salt balance, and the Ramsar record says the Chilika Development Authority received the convention’s Wetland Conservation Award for 2002 for the work.

In January 2026 Odisha’s forest department counted 11,32,200 birds on the lake (about 1.13 million) and 159 Irrawaddy dolphins in two separate censuses. The 159 dolphins were the largest number at any site in the state.

Listed on 1 October 1981, the same day as Keoladeo

The Ramsar Sites Information Service gives Chilika’s designation date as 1 October 1981 and its area as 116,500 hectares, which is 1,165 sq km. The Chilika Development Authority (CDA), the Odisha government body that manages the lake, describes Chilika as India’s first Ramsar site. The Ramsar record for Keoladeo National Park in Rajasthan carries the same date, so on the convention’s own dates the two sites share first place. tuput’s report on the latest Indian Ramsar additions covers how the list has grown since.

The water spread of the lake runs from 1,165 sq km in the monsoon down to 906 sq km in summer, according to Ajit K. Pattnaik’s case study for the International Lake Environment Committee, which relies heavily on the authority’s own monitoring. A sandy ridge separates the lagoon from the sea, and 52 rivers and rivulets drain into it. The same study says sand moving along the coast, about 0.1 million tonnes a year, tends to shift the lake’s mouth every year.

Why it went on the Montreux Record in 1993

Ramsar’s record shows the entry on 16 June 1993 and says siltation and sedimentation were choking the mouth of the lake. Pattnaik’s study fills in the chain. Shoals had formed along the channel leading to the sea, the mouth kept shifting, and less seawater reached the lake. By 1995 to 1996 average salinity had fallen by a third, and the northern sector stayed at zero salinity all year.

Freshwater weeds spread as the salt dropped. Water hyacinth and water ferns covered an estimated 21.34 sq km in October 2000. Slow drainage also waterlogged more than 50,000 hectares of farmland around the lake, the study says. Fish and prawn landings, which both the CDA and Pattnaik put at about 1,600 tonnes a year through the 1990s, had fallen to that level.

The new mouth of 23 September 2000

The CDA commissioned the Central Water and Power Research Station to model the lake. Its study concluded that shoals and the wandering mouth had cut the tidal flow, and it recommended a new outlet closer to the lake. Pattnaik writes that an artificial mouth turned out to be a long-standing wish of the local communities, which village meetings confirmed.

The new mouth opened on 23 September 2000 and shortened the outflow channel by 18 km. The channel leading to it was desilted as well. The central government’s Special Problem Grants were the main source of money for the restoration, about Rs 1,250 million (Rs 125 crore, or US$17.2 million) in total, according to the study.

The CDA’s account of the results runs as follows. Salinity now falls gradually from the mouth into the lake, which guides young fish, prawns and crabs in from the sea. Freshwater weed cover dropped by 172 sq km. Seagrass meadows grew from 24.8 sq km before the opening to 86.84 sq km in 2004, 102 sq km in 2012 and 152 sq km in November 2018. Six commercial fish species and one shrimp species that had disappeared were recorded again.

Removal on 11 November 2002

Ramsar sent an advisory mission to Chilika in 2001, and the record shows removal from the Montreux Record on 11 November 2002. The CDA says the removal followed the mission’s recommendation. The Hindu reported on 15 November 2002 that the lake had been taken off the record after remedial measures by the authority to restore the lagoon’s ecology.

The CDA also says Chilika was the first site in Asia to be removed from the record. The Ramsar record does not make that claim, so it rests on the authority’s word alone.

What changed for the fishing communities

The CDA’s home page says the lagoon supports about 0.2 million fisherfolk, while its at-a-glance page says more than 0.15 million live in and around it. Pattnaik’s study gives 200,000 fishers and 800,000 people in the wider lake-basin community.

The authority’s landing records show the change after the mouth opened. Landings were 4,889.21 tonnes in 2000-01, 11,988.88 tonnes in 2001-02 and 14,053.22 tonnes in 2003-04, which the CDA calls an all-time high. The authority’s site says average family income rose by more than Rs 50,000 a year. Pattnaik’s study puts the rise at US$1,040 per family per year, and says fishers began regulating mesh sizes and avoiding juvenile fish on their own.

The next stage is clearing the enclosures. On 8 March 2021 the CDA’s chief executive filed an affidavit in the Orissa High Court, in a public interest case on the wetland’s ecology, saying more than 15,500 hectares of the lake were illegally encroached. Of that, more than 12,131 hectares were under gherries, net enclosures used to raise tiger prawns, and about 1,440 hectares were under prawn ponds. Down To Earth notes that the two parts add up to less than the headline figure and does not explain the gap.

Removal resumed on 24 June 2021 after a pause for Covid-19. A Ganjam tehsildar said about 29 of 97 acres of ponds in his area came down on the first day. A Hindustan Times report republished by the International Collective in Support of Fishworkers, with no date on the copy, says gherries had grown from about 5 sq km in 1989 to 175 sq km, that officials had cleared more than 85 per cent, and that the enclosures had affected the livelihoods of about 200,000 traditional fishermen.

Irrawaddy dolphins, counted three ways

The dolphin here is the Irrawaddy dolphin, a coastal and lagoon species, and not the river species covered in tuput’s piece on the first national river dolphin count.

The state Wildlife Wing’s census of 20 January 2026 found 159 Irrawaddy dolphins in Chilika, the same as in 2025, out of 208 counted along the Odisha coast. Down To Earth reports that dolphin estimation began in Chilika in 2008 and spread to all coastal forest divisions in 2015. A forest officer quoted by PTI said Chilika still has the highest concentration of Irrawaddy dolphins in one area in the world, and the CDA also describes the lake as home to the largest group of them.

The older counts come from other methods. Pattnaik’s study says the population rose from 70 in 2003 to 145 in 2013. The CDA’s ecology page adds that a 1991 survey by Dean and Saaltink reported 60 to 70 dolphins regularly seen in the channel between Satapada and the Bay of Bengal. Dipani Sutaria’s photo-identification study of the resident dolphins, run from November 2004 to December 2006 and summarised by the Important Marine Mammal Area programme, estimated 109 to 112 dolphins with one set of statistical models and 140 with another.

Two readings of the flat 159 are on record. Chilika’s divisional forest officer, quoted by PTI, suggested that some dolphins may have moved to other areas, and a former principal chief conservator of forests told Down To Earth that some may have migrated and that the species breeds slowly. The marine mammal fact sheet says there is no known movement of dolphins into or out of the lagoon. It lists entanglement in fishing gear as the main threat and unmanaged dolphin-watching as another, and says mortality has reached as high as 7 per cent, mostly from entanglement. The wildlife activist Biswajit Mohanty told Down To Earth that prawn gherries and nylon nets stress the habitat.

The species is listed as Endangered worldwide on the IUCN Red List, according to the fact sheet. Sutaria and Marsh wrote in 2011 that the Chilika population had not been assessed under IUCN Red List criteria. People from 17 villages along the outer channel take visitors out to watch the dolphins, Pattnaik’s study says, and credits the trade with improving their incomes.

11,32,200 birds on one Sunday in January 2026

The mid-winter census on Sunday 18 January 2026 ran from 6 am to noon across all 51 forest divisions of Odisha. At Chilika it counted 11,32,200 birds of more than 196 species, against 11,27,228 in 2025, a rise of 4,972. The state’s chief wildlife warden gave the figures. Migratory birds numbered 11,10,257, up from 10,87,227.

Northern pintail led with 2,18,993, followed by Eurasian wigeon at 1,53,318 and gadwall at 1,43,127. Nalabana Bird Sanctuary, an island in the lake, held 3,97,587 birds of 106 species, up from 3,43,226 of 92 species. Two species were new to the lagoon, the plain martin and the Bengal bush lark. Staff of the Zoological Survey of India, the Bombay Natural History Society and the Odisha Biodiversity Board took part.

The CDA says Nalabana became a sanctuary in 1987 and that a 1996 estimate put as much as 75 per cent of Chilika’s wintering birds there. Its ecology page lists 222 bird species. Pattnaik’s study counts 164 wetland bird species, of which 66 are intercontinental migrants from places such as the Caspian Sea, Lake Baikal and Siberia. The CDA’s at-a-glance page adds an estimated two million birds visiting in 1989 to 1990, a figure that predates the lake’s decline.

The 2023-24 report card

The CDA publishes a health report card for the lagoon, produced with the Application Network of the University of Maryland Center for Environmental Science and others, and the seventh edition covers 2023 and 2024. It gives Chilika an overall B+, up from a B in 2012. Dissolved oxygen, chlorophyll-a, phytoplankton diversity and fish size scored A. The dolphin indicator, which compares the annual count with the highest count on record, scored C.

Fish, prawn and crab landings averaged 20,657.30 tonnes a year in 2023 and 2024, up 6.86 per cent on 2021 and 2022. The catch was worth an average Rs 38,514.99 million a year (about Rs 3,851 crore), and the average annual income per active fisher was Rs 85,001, which is 2.39 per cent above the earlier two-year figure.