Birds of Mangalajodi: A visual journey into Chilika’s avian paradise

Chilika Lake: Location, Type and International Recognition

Location and Type

• Chilika Lake is situated in the state of Odisha along the eastern coastline of India, adjoining the Bay of Bengal.
• It lies to the south-west of the Mahanadi delta and extends across the districts of Puri, Khordha, and Ganjam.
• The lake is connected to the Bay of Bengal through a sea mouth, the maintenance of which is crucial for regulating salinity and sustaining ecological balance.
• A key development in recent decades has been the opening of a new sea mouth in 2000, which significantly improved water exchange, enhanced fish production, and restored the lagoon’s ecological health.
• Chilika Lake is a brackish water coastal lagoon, formed by the mixing of freshwater inflows from rivers such as Daya and Bhargavi with saline seawater.
• It is the largest brackish water lagoon in India and one of the largest in the world.
• The lake exhibits a clear ecological zonation, with freshwater conditions dominating the northern sector, brackish conditions in the central region, and marine influence in the southern part.
• This gradient supports high biodiversity, including fisheries and species such as the Irrawaddy dolphin, making it ecologically and economically significant.

International Recognition

• Chilika Lake has been recognized as a wetland of global importance under the Ramsar Convention since 1981.
• Its inclusion highlights its ecological significance, particularly as a habitat for migratory birds along the Central Asian Flyway and for its rich aquatic biodiversity.
• A major point of importance in current affairs is its association with the Montreux Record.
• Chilika was the first Indian wetland to be placed on the Montreux Record due to ecological degradation caused by siltation, reduced salinity, and declining biodiversity.
• However, through targeted restoration measures, including hydrological interventions and community-based management, the lake witnessed substantial ecological recovery.
• As a result, it became the first wetland in Asia to be removed from the Montreux Record, a globally acknowledged success in wetland restoration.

Mangalajodi: Freshwater Marsh Zone of Chilika

• Mangalajodi is located on the northern fringe of Chilika Lake in Odisha.
• It represents the freshwater marsh zone of Chilika, unlike the lagoon’s brackish and marine-influenced sectors.
• The area receives freshwater mainly from distributaries of the Mahanadi River.
• It consists of shallow wetlands, mudflats, and marshy vegetation, not deep open water.
• Water depth is generally very shallow (often <1 metre), suitable for wading birds.
• It supports large congregations of migratory birds during winter season.
• It lies along the Central Asian Flyway, an important migratory route.
• It is known for hosting lakhs of birds annually, especially waterfowl species.
• Common bird groups include ducks, geese, herons, egrets, and waders.
• It is recognized as one of the major birding hotspots in India.
• It is often called the “Bird Paradise of Chilika”.
• It differs from the southern part of Chilika which is marine-influenced due to proximity to the Bay of Bengal.
• It is associated with community-led conservation model (local villagers involved in bird protection).
• It forms part of the Chilika Ramsar Wetland system under the Ramsar Convention.

Central Asian Flyway and Migratory Bird Movement

• Mangalajodi lies on the Central Asian Flyway, which is one of the world’s major migratory bird routes.
• This flyway connects the breeding grounds of birds in Siberia, Arctic regions, Central Asia and Northern Eurasia with wintering grounds in India and South Asia.
• Every year between October and March, nearly two lakh migratory birds arrive in Mangalajodi.
• These birds migrate mainly due to harsh winters in northern regions and search for warmer climate, food-rich wetlands and safe breeding conditions.

Important Migratory Birds

• Northern Pintail (Anas acuta) is one of the most dominant and abundant migratory duck species.
• Bar-headed Goose (Anser indicus) is notable for its high-altitude migration across the Himalayas.
• Gadwall, Northern Shoveler, and Common Teal are common dabbling ducks found in large numbers.
• Black-tailed Godwit and other waders (sandpipers, plovers) are common in shallow marsh zones like Mangalajodi.
• Bird population monitoring is conducted annually by the Chilika Development Authority.

Nalabana Bird Sanctuary inside Chilika

• Nalabana Bird Sanctuary is the core protected bird habitat located inside Chilika Lake.
• The word Nalabana means “weed-covered island.”
• It remains seasonally submerged during the monsoon and reappears during the dry season, making it a unique wetland island ecosystem.
• It was declared a bird sanctuary in 1987 and serves as one of the most important nesting and resting sites for migratory birds visiting Chilika.
• Nalabana is also the principal site for annual bird census operations and is one of the most protected avian habitats in eastern India.
• Its location inside Chilika is a very common prelims question.

Irrawaddy Dolphin and Other Important Fauna

• Chilika Lake is internationally famous for the presence of the Irrawaddy Dolphin.
• This species is mainly found in coastal, estuarine and brackish water ecosystems and is different from the Gangetic river dolphin.
• In India, Chilika is one of the most well-known habitats of the Irrawaddy Dolphin, especially near the outer channel and sea mouth region.
• The species is listed as Endangered by the IUCN.
• Apart from dolphins and birds, Chilika also supports fish species, crustaceans, prawns, amphibians and seagrass ecosystems, making it one of India’s most productive wetland systems.