While solitary individuals may be observed, they usually live in loose family groups of about 12 individuals. They have vocabularies of 12 or more calls in addition to basic instinctive cries. These diurnal animals will only occupy areas with a permanent body of water and some tree cover. They live in large, underground burrows with a ventilation shaft leading to the surface and an exit tunnel opening about 3 feet under water. Using their sensitive fingers to find clams in shallow water, they bring them to shore and pile them up, and after a few hours in the sun the clams open and the otters eat them. They spend much of their time playing in the water, and will fall to water when danger approaches. When they hunt in rice fields they aid farmers by ridding the fields of crayfish that damage crops. Like raccoons, they sometimes "wash" their food before eating it. If captured young, these otters make intelligent and charming pets. Malayan fisherman have even trained them to drive fish into nets for them.