Anacondas – Giants of the South American Waters

A massive serpent, which is often found in South America, is classified into four distinct species within the taxonomic genus Eunectes by researchers. 

Belonging to the boa family, they share close kinship with other members of their taxonomic group:

  • Boa constrictors
  • Tree boas
  • Rainbow boas

Their 4 known species are:

  • Bolivian anaconda (Eunectes beniensis)
  • Darkly-spotted anaconda (Eunectes deschauenseei)
  • Green anaconda (Eunectes murinus)
  • Yellow anaconda (Eunectes notaeus)

Among these, the green anaconda reigns as the largest, averaging around 20 feet in length, though some specimens exceed this size. 

Despite challenges in accurately determining their maximum length due to exaggerated reports, some claim lengths surpass 100 feet. 

At their average size, green anacondas can measure a foot wide and tip the scales at over 500 pounds.

Despite their similar appearance, pythons are not as closely related to boas and anacondas as commonly assumed. Their most recent common ancestor likely existed around 90 million years ago. 

Distinct reproductive strategies further set them apart: pythons are known for laying eggs, whereas many boas are ovoviviparous, with eggs hatching internally, resulting in live birth.

Interesting facts about this reptile animal

Explore distinct traits of each of the four species to understand their unique differences.

  • Bolivian species 

Initially thought to be a hybrid, genetic studies have led scientists to recognize this snake as its own distinct species.

  • Dark-Spotted species 

The population size of these elusive snakes remains uncertain to researchers. They are considered rare, with habitat destruction posing a threat. However, the extent of their decline is still unclear to scientists.

  • Green species 

The most famous and largest among the four species, with recorded individuals reaching 17 ft. and 215 lbs. Sightings of even larger specimens have been reported by people.

  • Yellow species 

Measuring a modest 12 ft. in length, the yellow species exhibits scales of a distinctive yellow hue, adorned with dark brown markings, staying true to its name.


All four species inhabit comparable environments, favoring aquatic habitats such as:

  • Rivers
  • Streams
  • Swamps
  • Flooded areas

Their muddy-colored scales provide excellent camouflage in turbid waters. At times, they venture onto land to hunt or bask, traversing tropical rainforests, savannas, and grasslands.

What is their diet?

These massive reptiles consume other creatures because they are carnivores. They consume almost anything that they are able to ingest. Their main hunting strategy is ambush, in which they wait for their prey to approach them.

Littler snakes consume fish, tiny mammals, frogs, juvenile caiman, birds, and other snakes. Adults eat a wide range of foods, such as:

  • Agouti
  • Pudu
  • Tapir
  • Capybara
  • Jacana

How they interact with humans?

There is some interaction between anacondas and humans. Nonetheless, as these snakes inhabit secluded areas, encounters with humans are uncommon. 

Sadly, these snakes are killed by people and their body parts are sold for use in traditional medicine and spiritual ceremonies.

Each and every species is likewise at risk from habitat loss. The fall in wildlife populations in such places is caused by the destruction of the rainforest for logging, agriculture, mining, and human population growth.

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