Anaconda [Photo by Elwin R. Sanborn/National Geographic]
Anacondas feed on fish, birds, reptiles, and small mammals, though they have been known to take the occasional domestic animal. The big snakes can be dangerous to people, though reports of deliberate predation are very rare.
Like other boas, anacondas are nonvenomous, and they often kill their prey by constricting it. Like other snakes, they swallow their prey whole.