The anaconda is a boa constrictor, and the largest of all snakes. It is believed that the name anaconda is derived from the South American Indian word combinations for elephant and killer. It is not poisonous. Known as the water boa, it lives near or in water, in swamps, marshes, brush covered river banks. To allow the anaconda to stalk its prey while in the water, the anaconda’s eyes and nostrils are positioned on top of its head to allow the body to be submersed under water and the eyes and nostrils to be above water. It strikes its prey as it comes to drink with its sharp teeth, coils its body around its prey and squeezes it to suffocate it, or drowns it. An anaconda can stay totally submerged in water for up to ten minutes. There are two types of anaconda, yellow or green: both have black oval patterns on their skins for effective camouflage under brush. The yellow anaconda (Eunectes notaeus) measures around 10 to 12 feet in length, and is found in northern Argentina, Paraguay, south-eastern Bolivia and Brazil. The green anaconda, or common anaconda (Eunectes murinus) can measure up to 25 feet in length and 3 feet in girth, and is found east of the Andes, in the river systems of northern and Amazonian South America; it is the heaviest and thickest snake in the world. Each anaconda has a unique pattern on the underside of its lower tail, which acts as a form of identification, similar to a human fingerprint. A carnivorous animal, its typical diet consists of fish, birds, deer, peccaries (wild pigs), large rodents (pacas, agoutis), small caimans. The ligaments holding its jaws together stretch to allow the passage of the head of the prey, allowing the rest of the prey’s body to fold inward for easy ingestion. Its digestive system is slow, and it does not need to eat for a few weeks to a few months, depending on the size of the prey. The rainy season signals the onset of courtship, and males and females usually mate in water. Gestation lasts about 6 months. It is viviparous and between 20 to 30, and up to 100 live baby anacondas are born at a time, measuring about two feet long. Even though newborn anacondas can swim and hunt by themselves shortly after birth, they are easy prey for other predators. Anacondas reach sexual maturity around 3-4 years of age and live up to thirty years. The largest anaconda ever encountered was spotted in British Guiana and it measured 34 feet.