Anacondas are group of large snakes of the genus Eunectes. They are large snakes found in tropical South America. Four species are currently recognized. Although, the name "Anaconda" applies to a group of snakes, it is often used to refer only to one species in particular - the common or Green Anaconda (Eunectes murinus), which is the largest snake in the world by weight and the second longest. The average length of of the Green Anaconda is 6 meters (20 ft.) with a top length of 8.8 meters (29 ft.). It's girth can be upwards of 30 cm (12 in.) and can reach a weight of 227 kg (550 lb.).
Being native to South America, the Green Anaconda typically makes its home in swamps, marshes and streams. Their enormous size makes it much easier for them to swim in the water than to slither slowly on land. Their eyes and nostrils are on the top of their head allowing them to see and breathe while most of their body is under water. Most of the Green Anaconda's time is spent in the water hunting. Although, they use both sight and smell to hunt, they also have the ability to sense heat emitted by potential prey. Green anacondas prey on a variety of animals including fish, birds, tapirs, wild pigs, capybaras, and caimans. They’ve even been known to eat jaguars. Green anacondas have also been known to partake in cannibalism. Females, the larger of the sexes, have been reported to eat smaller male anacondas.
When anacondas first became available to hobbyist snake keepers, the majority were wild imports. Many of these animals had bad dispositions and parasites. It was all too common for them to fail to eat due to stress, illness and improper husbandry. A lack of knowledge at the time also precipitated high mortality rates. Green anacondas can live over 10 years in the wild. They can live up to 30 years in captivity.
Green anacondas spend most of their time alone. However, between April and May, males seek out females for the opportunity to mate. Often times, multiple males will pursue the same female. This results in “breeding balls” of up to a dozen males wrapped around a single female, all attempting to mate. The breeding ball can last up to 4 weeks. Once pregnant, the female will produce eggs inside her body. The eggs develop for 8-12 weeks and then hatch while still inside the mother’s body. She then gives birth to as many as 80 tiny snakes, each 30-60 cm (12-24 in.) in length.