Two or more researchers wade through a pond, probing with their toes for anything snakelike, and shuffling to ward off stingrays. Anacondas do not resist being handled. But grab its neck and the snake's composure snaps. By measuring the snakes, the scientists learned that what they thought were baby anacondas were actually adult males. A 500-pound female anaconda holds the record for the world's heaviest snake.
Llanos anacondas are fast swimmers, and scientists found that they roam large territories.
They are not poisonous, and kill by sinking their teeth into an animal, throwing coils around it and squeezing. They eat almost anything, from turtles to white-tailed deer. Reliable reports of people being eaten are rare. Balls last four to six weeks and still baffle researchers. DNA tests may answer the last question.