The green anaconda is a snake native to South America, and its geographical distribution extends east of the Andes, in countries such as Colombia, Venezuela, Guyana, Ecuador, Peru, Bolivia, Brazil, the island of Trinidad, up to the north of Paraguay.
Anacondas live in wetlands, swamps, and slow-flowing streams, primarily in the tropical rainforests of the Amazon and Orinoco basins. They are slow and clumsy animals on land, but can be stealthy and elegant in the water. Their eyes and nasal openings are on the top of their heads, allowing them to lurk just below the surface of the water and remain almost completely submerged, waiting for prey.
For now it is not a species present on the IUCN Red List, however the progressive destruction of its natural habitat puts the future of the anacondas at risk. All anaconda species are primarily nocturnal and tend to spend most of their lives in or near water sources.
Although they can reach high swimming speeds, they mostly tend to float below the surface of the water with their noses above the surface. When the prey passes close to its hiding place or approaches a stream to drink, the anaconda strikes, locking its jaws on the prey, then enveloping it completely with its coils.
The snake will then begin to tighten its grip until the prey is suffocated. Green Anacondas in the wild live for approximately 10 years. In captivity, however, they can live up to 30 years and beyond. For anacondas the length limit is estimated at about 6.7 m in total length.
This is consistent with findings from a review of the size at sexual maturity and maximum size of several snakes from North America, which found maximum size to be between 1.5 and 2.5 at se*ual maturity. The minimum size of anacondas to reproduce, in a survey of 780 individuals, is 2.1 m in length, indicating that the maximum size reached by anacondas following this model would be 5.3 m.
However, most of the anacondas analyzed were caught in llanos, which are more accessible to humans and host smaller prey items, while rainforests, which are less explored and have more abundant prey items, may host larger snakes.