Nocturnal in habit, the anaconda lie up during the day in shallow waters or sunbathe on a low branch, usually over water. Anacondas usually lie in wait by the waters edge waiting for its prey to come down to the waters edge to drink. Striking quickly with the head grabbing the unlucky prey and dragging it underwater so that it drowns. Sometimes the anaconda will hunt on land. The usual prey caught by the snake are birds, small mammals-deer, piccaries, and large rodents such as agoutis.
Fish are a large part of the diet.
Turtles and caimans are sometimes attacked. It is on record that a 25 foot anaconda killed and ate a 6 foot caiman. Snakes have a special jaw attachment that allows an anaconda to swallow such a large animal. A meal of this size will last the anaconda for several weeks. During this time the snake rests until the prey has digested.