Animals

There are four species of the anaconda snake, which live in the swamps and rivers of tropical South America. The Green Anaconda, which has been reliably reported in the 9 metre range (30 feet) in length (although most are considerably smaller). Although shorter than the longest recorded species, the Reticulated Python, it is considerably heavier and is bigger around. In fact, it is the heaviest snake species in existence: it can weigh 250 kg (551 pounds) and have a diameter of more than 30 cm (11.8 inches). Females average 6.7-7.9m (22-26ft) in length, while males average 3-4m (12-16ft). These are found mainly in northern South America.

The anaconda has a large head and a thick neck. Its eyes and nostrils are positioned on the top of the head, enabling the anaconda to breathe and to see its prey while its stocky body lies submerged under water. The extremely muscular anaconda is a constrictor and is not venomous; however, it still has teeth and powerful jaws that it utilizes to clench onto its prey. It grabs its victim and pulls it underwater, drowning the prey. The anaconda has a cavity called a cloaca which is where the intestinal and genito-urinary tracts empty, with spurs on either side of the cloaca, and a gland which emits a foul-smelling musk.

Despite the hold they have on the imagination, relatively little information was known about the anaconda until 1992 when the first study was made on the field biology of this species in the Venezuelan llanos by Dr. Jesus A. Rivas. They typically feed on large rodents, tapirs, capybaras, peccaries, fish, turtles, birds, sheep, dogs, and aquatic reptiles like caiman. They have been known to occasionally prey on animals as large as jaguars, deer, and attacks humans, although this is rare.

Younger anacondas feed on mice, rats, chicks, frogs and fish. Most local people kill these snakes on sight, out of the fear that they are man-eaters. In most instances, if an anaconda senses humans in the area, it will retreat in another direction. Human death by anaconda is quite rare. They themselves are preyed by jaguars, large caimans and by other anacondas. A wounded anaconda can also fall prey to piranhas.

Anacondas are usually coiled up in a murky, shallow pool or at the river’s edge. They wait to ambush their unsuspecting prey when they come down for a drink. Anacondas bite their prey with their sharp teeth, hold on with their powerful jaws and pull them under water. The victim may drown first or it may be asphyxiated in the anaconda’s muscular coils. Anacondas, true to the boa family, constrict their hapless victims to death.

The snake squeezes tighter each time its prey breathes out, so the prey cannot breathe in again. Suffocation does not take long. Anacondas swallow their prey whole, starting with the head. This is so that the legs fold up and the prey goes down smoothly. The Anaconda can swallow prey much bigger than the size of its mouth since its jaw can unhinge and the jaw bones are loosely connected to the skull. While the snake eats, its muscles have wave-like contractions, crushing the prey even further and forcing it downward with each bite.

Just about every species of snake on earth has teeth, but the anacondas’ teeth are not used for chewing. Most snakes’ teeth are used for holding onto their prey, preventing them from escaping. Some snakes have venom in two specially designed, extra long teeth which they use to kill their prey. Anacondas do have teeth, but their bites are neither fatal nor venomous. They rely on their enormous size and power to subdue their victims. It is possible to be bitten by an anaconda, but the bite itself would not be fatal. Like almost all boas, anacondas give birth to live young.