This lush wetland comprises serene mangrove fresh-water swamplands attracting a variety of migrant and endemic water birds and is a popular location for bird and nature enthusiasts. It is made up of six constructed tanks as well as three peripheral tanks that are part of an intricate irrigation system (dating back to the 12th century) that is nourished by the waters of the Deduru Oya River.
It has an area of 1,397 hectares or 13.97km², situated close to the Negambo – Puttlam railroad approximately 100km from Colombo on the A3 road. This wetland sanctuary is a ‘RAMSAR’ declared wetland and one of six found in the country. RAMSAR – (formally known as the Convention on Wetlands of International Importance, especially as Waterfowl Habitat,) is an international treaty for the conservation and sustainable utilization of wetlands (named after the city of Ramsar in Iran, where the Convention was signed in 1971.)
This tranquil sanctuary with water about four meters in depth, is home to many species of amphibians, mammals, reptiles and fish, attracting a variety of migrant birds who use it as a feeding and breeding ground during the migratory season.
Some of the bird species seen here are; the Brown Fish Owl, Black-winged Stilt, Common Moorhen, Cotton Teal, Lesser Whistling Teal, Grey Heron, Stork-billed, Common, Open bill, Grey-headed Fish Eagle, Indian Shag, Little Egret, Black-backed Yellow Woodpecker, Purple Heron, Purple Coot, Spoonbill, White-breasted Kingfisher, White-bellied Sea Eagle, and many more.