It is located from 35 km from Thanjavur and 65 km from Tiruchi. Karaivetai Vettaikudi Birds’ Sanctuary sprawls over 454 hc. of area. It is a large irrigation reservoir with water storage capacity of 228.5 mcft. The sanctuary has more than 100 species of birds from other countries, 8 species of mammals, 18 species of replies 15 varieties of fish. It is a wonderful sight to watch a large number of birds from other parts of India and foreign land like Siberia and Russia visiting the lake to feed, rest and breed. Notable once are bareheaded goose, gray pelican, glossy ibis, white stork, rosy pastors, golden orioles and 13 species of ducks and 19 species of small waders. One can get better view in the early morning or evening. Best time to visit is between November and January.