The King’s Project area at Laem Pak Bia is a really good birdwatching site in Thailand. However, any visit is certain to result in sightings of large water monitor lizards in and around the water, as well as birds. Many people ask me what such large lizards eat, and I have long suspected that they eat each other, although I have observed them stalking Pond Herons unsuccessfully. On Sunday 23rd March 2008, Andreas Egelund Christensen and myself saw a large water monitor and stopped to take photographs of it, only to turn a corner and see a much larger monitor in the process of eating one of its own kind. The large monitor was just over 2 metres long, from nose to tail, and the dead monitor was over 1 metre long. We didn’t see the large monitor make its kill, but the dead creature showed no sign of having been run over, instead it had a large gash in its neck which seemed to have been made by the jaws of the cannibal.
Below are the photos, click for larger versions.
As we watched, the predatory monitor was very reluctant to leave its catch, but eventually slipped into the water. However, when we returned to the same spot 10 minutes later it had returned to resume its meal.