We use feces to investigate diet and activity areas of butaan. In total we have examined more than 1500 samples, possibly the largest ever collected for a single population of reptiles.  Butaan and their relatives are huge specialised frugivores, much bigger than any other specialised frugivorous animal in  the Philippines. They need a constant supply of fruit but lack the wings that allow other frugivores to forage in different forest fragments. Large and immobile, the butaan depends on a very narrow range of foods.