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Largest Snake in the Amazon: Anaconda Facts

  |   Amazon Facts

The Anaconda is a well-known species in today’s culture. Movies, books and the internet boast the dangers of this "monster-like" snake. But are all of these rumors true? You might be wondering if you'll stumble upon the Anaconda snake during your Amazon river cruise. Before you hesitantly pack your bags to the Amazon jungle, here are a few surprising Anaconda facts you should know:

The Green Anaconda (Eunectes murinus)

The Green Anaconda (Eunectes murinus)

1. The Name Anaconda 

The name Anaconda (or Eunectes) snake refers to a group of snakes found in the tropical regions of South America. Four species are currently recognized by the name, Eunectes, which means good swimmer. The Green Anaconda (Eunectes murinus) is the most well-known of these four species, and it is usually what comes to mind when you picture the large snake. In fact, it is the largest of the Anaconda family! 

2. How Big are Anaconda Snakes?

Many legends and lore circulate around the length of the Giant Anaconda. The Green Anaconda, or Eunectes murinus, is the heaviest, largest and longest snake in South America, growing up to 5 meters in length (17 feet). In terms of diameter and weight, it’s not only the largest in South America and the Amazon rainforest, but in the World. For length however, the Python takes the title of the longest snake. 

During the days of President Teddy Roosevelt, the Wildlife Conservation Society offered a $50,000 reward to anyone who could deliver a live snake measuring over 30 feet in length. The offer terminated in 2002, to discourage people from disturbing these animals from their natural habitats. 

3. The Smallest Anaconda 

The smallest species of Anaconda, the Yellow Anaconda (Eunectes notaeus) measures to be 3-4 meters in length (that’s still quite a large snake!). The females grow larger than the males and both live in aquatic habitats. While out on an Amazon jungle walk, keep an eye out for swamps and marshes, maybe you will be lucky enough to see an Anaconda snake peaking through! 

Yellow Anaconda (Eunectes notaeus)

Yellow Anaconda (Eunectes notaeus)

4. The Rarest Anaconda 

The other two species of Anacondas, the Dark-Spotted Anaconda (Eunectes deschauenseei) and the Bolivian Anaconda (Eunectes beniensis), are quite rare, and little is known about them, though they both have estimated measurements of 15-16 (approx. 5 meters) feet in length. Like the name suggests, Bolivian Anaconda can be found in the Bolivian Amazon rainforest while the Dark-Spotted Anaconda roams around the Brazilian Amazon. 

5. The Giant Anaconda Legend: True or False? 

False. The unofficial species is supposed to be able to exceed 40-60 feet in length, and is reportedly rarely seen.  Unfortunately, (or perhaps fortunately), this snake of mythical proportions isn’t real.  At least, its existence has never been verified.  There used to be, a now extinct, species of enormous snake known as the “Titan Boa”.  It bore a close resemblance to the Anaconda and shared a similar habitat. It is not unfathomable (just highly unlikely) that some of the “Giant Anaconda” sightings were actually just extraordinary extant Titan Boa sightings. 

Overall, though, the Anaconda is an enormous snake– just not quite the length some people have made them out to be. Rather, an interesting Anaconda fact is that they are officially the largest snake in the world, meaning they are the most heavily built of any snake alive today.  The heaviest Anaconda was a Green Anaconda that weighed in at an immense 97.5 kg (215 lb)!

Amazon Legend, the Giant Anaconda

Amazon Legend, the Giant Anaconda

6. Anaconda’s Relationship with Humans 

The Anaconda has been given a bad reputation over the years of being a "man-eater", as a result of movies and media. Even in Amazonian folklore, the Giant Anaconda snake is called an “Encantado,”  a shapeshifting mythical creature known for kidnapping humans they fall in love with. While there have been claims and fake photos of Anacondas eating humans, it is unverified, and most definitely not true.  There was some stir recently over a Discovery Channel special called, “Eaten Alive”, where a naturalist wearing a snake-proof suit was supposed to be eaten by a Green Anaconda.  The Anaconda wasn’t prone to eat the naturalist at all, was frighten and tried to escape. The Anaconda only attacked him after much provocation.  Many people turned to Social Media to express their outrage of this irresponsible stunt, criticising Discovery Channel for airing something so completely out of scientific nature that would cause harm to the animal. 

That being said, while an encounter with an Anaconda snake could be dangerous, it is highly improbable that the Anaconda would try to hunt or eat you.

7. What do Anacondas Eat?

So, what do Anacondas eat?  When it comes to the Amazon food chain, all four Anaconda species are practically on top, with their only predators being the occasional Caiman or Jaguar.  The majority of a Green Anaconda’s prey are fish, birds, and small mammals which venture too close towards the water’s edge.  They occasionally eat other reptiles as well, including other Anacondas! The reason for cannibalism among the species isn’t quite understood, other than it usually takes place when a larger female eats a smaller male– that’s nature for you! It is also true that Green Anacondas are capable of eating larger animals such as Capybaras, Tapirs, and even Caimans, though they tend not to do so on a regular basis.  The Yellow Anaconda’s diet consists of the same foods as its larger cousin, but it also has a taste for birds’ eggs and fish carrion. It's safe to say the Jaguar has competition for its King of the Jungle title. 

8. Are Anaconda Snakes Venomous?

Nope! All four species of Anaconda aren’t venomous and instead use constriction to subdue their prey.  When an Anaconda sees its prey come down to the water’s edge, it will swim quickly but quietly towards it, keeping just out of sight.  When the time is right, an Anaconda will strike, using its immensely muscular body, and constrict the animal until the unlucky victim dies of asphyxiation.  One of the more talked about anaconda facts that is true is how an Anaconda is able to then “unhinge” its jaws in order to swallow such large prey.  The reason an Anaconda is capable of managing such a feat is because it’s lower jaw isn’t fused to its skull.  This makes for one enormous bite.  After a meal the size of a a large mammal, an Anaconda will not need to eat again for months.  

9. Where Can I find an Anaconda?

All four species of Anaconda can be found throughout South America, but they dwell predominately in the Amazon and Orinoco river basins.  Anacondas are semi-aquatic and thrive in slow moving streams, rivers, and other muddy, marshy environments.  These “Water Boas”, as Anacondas are sometimes called, tend be slow and unwieldy while on land, and instead use their sleek bodies to swim swiftly through the water. Anacondas are primarily nocturnal snakes, though can be seen active throughout the day.  An interesting Anaconda fact is that their eyes and nasal openings are higher up on their head than most snakes.  This nifty feature allows for them to stalk their prey while staying nearly submerged beneath the water’s surface.

Green Anaconda in Water

Green Anaconda in Water

10. Anaconda Snake Behaviour

Anacondas are solitary snakes and only get together during the mating season which takes place between April and May.  During this time the snakes will group together in odd clusters known as “breeding balls”, where up to twelve males will try to mate with one female.  These “slow motion wrestling matches” can last for over four weeks at a time! 

A female Green Anaconda can give birth to 60-100 live young.  Baby Anacondas are only two feet in length and receive no maternal nurturing growing up.  Over the next few years, the Anacondas will grow to immense proportions until they reach adulthood, at which point their rate of growth will drastically decrease.  All four species of Anaconda have a lifespan of about 10 years in the wild. During this decade of their life, these snakes will grow to become one of the largest and most iconic in the world.  Dangerous– but fascinating– the Anaconda is sure to be one snake you won’t forget in a hurry.

So what are you waiting for? Now that you know some amazing facts about this extraordinary  creature, try to spot an Anaconda for yourself during your Amazon river cruise in Peru, Brazil, Ecuador or Bolivia!  Who knows?  You could even see one reaching over 30 feet!  Wouldn’t that be an incredible Anaconda fact to carry around?  

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