About Chilika Lagoon

Chilika Lagoon, internationally reputed as "RAMSAR SITE" is an unique ecosystem of the globe forming the Largest Asian Brackish Water Lagoon, situated between latitude 180 28’ to 190 54’ North and longitude 850 05’ to 850 38’ East covers part of Puri, Khurda and Ganjam Districts. The main lagoon is connected to the Bay of Bengal by a channel of 1.2 Km width and 60 Km length which runs parallel to the Bay of Bengal with an inter space of 1 Km width with Casuarina plantations. The water spread area varies from 900 sq Km in summer to 1150 sq Km in rains.

Chilika is like a work of art, created by the ceaseless crafting of its three basic elements – water, salt and earth – by nature. In the monsoons, the rivers Daya, Bhargavi and Sulia and numerous other streams bring large quantities of fresh water estimated to be 300000 cusecs, into the lake. The Daya and the Bhargavi, being distributaries of the powerful Mahanadi, also bring an estimated 13 million metric tonnes of silt, which settles on the shallow bed of the lake. With the fresh water come large numbers of fish and aquatic plants, and one can see water plants blooming over large parts of the lake. The birds which are year-round residents of Chilika breed now, when food is plentiful and the air seems filled with insects. The rich organic silt and the detritus of water plants allow the myriad creatures that inhabit the bottom of the lake to grow. These benthic creatures themselves form the food for a variety of animals.

As the monsoon retreats, fresh water begins evaporating and the sea brings saltwater through Chilika’s narrow mouth. With the sea water comes marine life – phytoplankton, prawns and other invertebrates of all shapes and sizes, over a hundred species of fish, and dolphins and dugongs. All the animals come to feed, some to breed, some to develop to maturity from juveniles. The fresh water species gradually dwindle away, some to disappear till the next monsoon, while others get restricted to small areas in the huge lake.

Meanwhile, icy polar winds surge into the great northern landmass of Asia, sending the great avian travelers on their annual migration southward. Birds begin arriving at Chilika from late October and within a month thousands congregate in different parts of the lake. They remain for several months and the last stragglers depart to their northern breeding grounds by the end of March.

But Chilika today is also an ecosystem under siege. The vast amounts of silt brought by the Daya and the Bhargavi are making the lake even shallower. The great masses of weeds are making the lake even shallower. Some people believe that the number of migratory birds visiting Chilika is slowly decreasing. In the south of the lake, mercury is being found in the water in increasing concentrations. Fish yields appear to be dropping, as over fishing takes its toll. Chilika thus urgently needs a management strategy that can retain its unique biodiversity while maintaining the livelihoods of the thousands of people who depend on it.