Common lizard of wet lands such as mangroves, tanks, paddy
fields, canals and also streams in forests of all climatic zones from coasts to mid hills. But Deraniyagala mentioned that Water monitor is
absent in areas subject to drought that are frequented by wild boar which prey
upon it (A Colored atlas of some vertebrates from Ceylon – Tetrapod reptilia Vol
2 -1953). He also indicated that it is unknown from south-east part of the
country from Hambegamuwa to Tissamaharama. However recent researches on
distribution of this lizard suggested that it is present in that area excluding
Yala National Park [Probably due to the high abundance of crocodiles] but very rare (Lizards of Sri Lanka – Ruchira Somaweera 2009). It
is mainly a scavenger and feed on carrions, fishes, crabs, eggs of water birds,
turtles and crocodiles, birds, small mammals, snakes etc.