Nelapattu Bird Sanctuary is one of the best breeding grounds for Spot-billed Pelican in the country. Covering an area of 4.5 square kilometres, this lake serves as a nesting colony for thousands of migratory birds in winter. These birds build their nests on the Barringtonia sp. trees surrounding the lake.
The bird species that nest here include Painted Stork, Grey Heron, Eurasian Spoonbill, Darter, Little Cormorant, Indian Shag, Spot-billed Pelican, Black-headed Ibis, Glossy Ibis, Little Egret, Intermediate Egret, Great Egret, Black-crowned Night Heron, Pond Heron and Asian Openbill Stork. Hundreds of Garganey Teal, Northern Pintail, Gadwall and Northern Shoveler can also be seen on the lake. The best time to visit this place is from November to March.