For the first time ever, green anacondas (Eunectes murinus gigas) were observed mating at the Emperor Valley Zoo! During this time, several competing males formed a breeding ball around the female. This ritual that can last up to four weeks! Female anacondas can give birth to a 2 to 3 dozen live young. The green anaconda, the largest snake species in the world (by girth) are native to Trinidad. This reptile can reach up to 20 to 30 ft in length and weigh up to about 550 lbs!