Ecosystem role:
As apex predators, green anacondas help regulate the populations of prey species in their habitat. By preying on various animals, they contribute to maintaining a balance in the ecosystem, preventing the overpopulation of certain species that could otherwise have negative impacts on vegetation and other fauna. The green anaconda influences the distribution and behavior of other organisms. This can lead to adaptations in prey behavior, such as changes in feeding habits, time spent foraging, or areas frequented, which can have cascading effects on the entire ecosystem.
Although adult anacondas have very few predators, newborn and juvenile anacondas are vulnerable to predation themselves during their early life stages. Various predators, including birds, mammals, and other reptiles, may target newborn and juvenile anacondas as a food source. This predation pressure contributes to the regulation of anaconda populations, thus maintaining the balance of ecosystems.
Threats and conservation
The main threats stem from human activities and encounters. Its large size, coupled with fear, leads to persecution and localized killings. Hydroelectric dams and oil drilling contribute to the destruction of its aquatic habitats in Colombia, Peru, and Venezuela. Some populations in Paraguay are critically endangered due to beach tourism and human impact near the Laguna Blanca reserve. The species is exploited for its skin, used for leather accessories, and the fat is utilized in traditional medicine in parts of Peru and northeastern Brazil and the Guianas.
Due to its large range and occurrence in numerous protected areas within the range, the species is listed as Least Concern. This species can be locally common in some parts of its range. However, there is no data on population trends, so research on population size and trends is needed to better understand the conservation status of this species.
Cultural Significance:
Because of its large size, the green anaconda is persecuted throughout its range due to fear but also predation on pets and livestock. The species faces some human exploitation, with its skin sometimes used for leather accessories and its fat incorporated into traditional medicine in specific regions. Despite local stories of anacondas feeding on humans, there is little evidence supporting such claims. Green anacondas have made their mark in popular culture, often portrayed as colossal creatures capable of consuming adult humans. While these portrayals are common in horror literature and films, it's important to note that there is no verified evidence of this species consuming humans in reality. This is unlike pythons in Asia, which have been implicated in several documented cases of human predation.
One indigenous myth tells the story of Yube, a man who transformed into an anaconda after falling in love with an anaconda woman. He went to live with her in the deep waters, where he discovered a hallucinogenic drink with healing powers and knowledge. One day he decides to leave the water and goes to live with a human wife. One day when looking for fruit, he accidentally steps into the river with one foot, and the anaconda woman and her children crush him and break his bones. Before dying, he sings the song of the nixi pae or ayahuasca. From his body, the yagé vine and chacruna leaf grow which are used in the preperation of ayahuasca.
Recent studies:
In a report from 2023, the golden dorado fish has been observed to follow the green anaconda in a clearwater river in Brazil, in what is probably a “nuclear-follower feeding association”, whereby one organism disturbs the sediment and the other follows and opportunistically feeds on any released food-items. While it is often thought that anacondas don't climb trees due to their heavy build, a report from 2017 mentions arboreal behavior of three anacondas in Ecuador which were found about 10 meters up in the trees. These were all small to medium in size, the reason for this arboreal behavior remains unknown.