Kokkilai lagoon is an estuarine lagoon

Lagoon

A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...

 in Mullaitivu District

Mullaitivu District

Mullaitivu district is one of the 25 administrative districts of Sri Lanka. The district is administered by a District Secretariat headed by a District Secretary appointed by the central government of Sri Lanka. The headquarters is located in Mullaitivu town...

 and Trincomalee District

Trincomalee District

Trincomalee district is one of the 25 administrative districts of Sri Lanka. The district is administered by a District Secretariat headed by a District Secretary appointed by the central government of Sri Lanka...

, north-east Sri Lanka

Sri Lanka

Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

. The town of Kokkilai

Kokkilai

Kokkilai or Kokilai or Kokkulaay is a town in the Mullaitivu District, Sri Lanka. It is located about 40 km south-east of the District capital Mullaitivu. It is a coastal town, located next to Kokkilai lagoon, it is also close to Trincomalee District border.- See also :* 1985 Kokkilai...

 is located on a sand bar between the lagoon and the Indian Ocean

Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

.

The lagoon is fed by a number of small rivers, including Churiyan Aru. It is linked to the sea by a narrow channel

Channel (geography)

In physical geography, a channel is the physical confine of a river, slough or ocean strait consisting of a bed and banks.A channel is also the natural or human-made deeper course through a reef, sand bar, bay, or any shallow body of water...

 that is very often blocked by the sand bar. The lagoon's water is brackish.

The lagoon is surrounded by a densely populated region containing cultivated land, scrubland and open forest

Forest

A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...

. The land is used for prawn

Prawn

Prawns are decapod crustaceans of the sub-order Dendrobranchiata. There are 540 extant species, in seven families, and a fossil record extending back to the Devonian...

 fishing

Fishing

Fishing is the activity of trying to catch wild fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping....

, paddy

Rice

Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

 cultivation and some shifting cultivation

Shifting cultivation

Shifting cultivation is an agricultural system in which plots of land are cultivated temporarily, then abandoned. This system often involves clearing of a piece of land followed by several years of wood harvesting or farming, until the soil loses fertility...

.

The lagoon has extensive sea grass beds and small areas of mangrove swamp and mudflats. The shallow waters of the lagoon attracts a wide variety of water bird

Water bird

The term water bird or waterbird is used to refer to birds that live on or around water. Some definitions apply the term especially to birds in freshwater habitats, though others make no distinction from birds that inhabit marine environments. In addition, some water birds are more terrestrial or...

s including pelican

Pelican

A pelican, derived from the Greek word πελεκυς pelekys is a large water bird with a large throat pouch, belonging to the bird family Pelecanidae....

, cormorant

Cormorant

The bird family Phalacrocoracidae is represented by some 40 species of cormorants and shags. Several different classifications of the family have been proposed recently, and the number of genera is disputed.- Names :...

, herons, egrets, wild duck

Wild duck

Wild Duck can refer to:*The Wild Duck, play by Henrik Ibsen*mallard, species of wild duck...

, stork

Stork

Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family Ciconiidae. They are the only family in the biological order Ciconiiformes, which was once much larger and held a number of families....

, waders and pink flamingoes.

The lagoon was designated a wildlife sanctuary in 1951.