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Anacondas: The Largest Snakes in the World

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Hassam loves researching and writing about all kinds of subjects, including geography and zoology.

Anacondas are semi-aquatic constrictors and the world's largest snakes by weight.

Anacondas are semi-aquatic constrictors and the world's largest snakes by weight.

Anacondas: Appearance, Location, Behaviour and More

Anacondas are huge snakes that are also known as water boas. The name suits them well since they are semi-aquatic and live in or near swamps and back river systems. They are also found in tropical rainforests, savanna grasslands, scrub forests and deciduous forests.

The anaconda's weight is usually supported by water. They prefer to live in water but enjoy spending time on land in shallow caves, by the water's edge or on river bank trees to bask in the sun. They are more often found in swamps and calm waters than in swift-moving rivers.

Due to their enormous size, they appear sluggish on land or in trees, but in water, they are capable of surprising speed. They can stay completely submerged for 10 minutes. They are agile swimmers but sometimes prefer to let the river's current carry them downstream with only their nostrils above the watery surface.

Anacondas in the wild spend most of their time in rivers hunting for food. An anaconda's lifestyle is nocturnal, and they are shy, solitary creatures, not easily seen.

In this article, you'll learn about anacondas':

  • Physical characteristics
  • Geographic location
  • Species
  • Behaviour and diet
  • Reproduction and lifespan
  • Interactions with humans
Anacondas are muscular with loose, scaly skin.

Anacondas are muscular with loose, scaly skin.

Physical Characteristics

Anacondas, as semi-aquatic constrictors, are fairly muscular snakes with loose skin that can absorb lots of water.

Appearance

The anaconda has brownish-green, scaly skin that glistens but is dry to the touch. The nostrils are on the top of the snout, letting the snake breathe easily when it is in water. It 'smells' with its tongue, has no fangs and is non-venomous.

It has a large head and a thick neck. It emits a foul-smelling, brownish musk, which is quite poisonous to small organisms. This may prevent ticks and leeches from attacking them when they are out of water for long periods. It continues to grow all its life, getting bigger and bigger.

Size

Anacondas are famous for their size and weight. They are considered to be big snakes. These snakes may reach a length of over 29 feet with a diameter of more than 12 inches, and the females are much larger than the males. There are many stories about anacondas being much longer, but they cannot be confirmed.

There are some historical reports by an early European explorer of the South American jungles seeing giant anacondas up to 100 feet. Some native people of South America have reported seeing anacondas up to 50 feet. However, none anywhere near that size has ever been caught and measured.

It is thought that perhaps these sightings may, in fact, have been of a Titanoboa, a prehistoric snake that lived 60 million years ago and grew up to 50 feet long, weighing in at over two tonnes – the largest snake in history. Its fossils were found in Colombia in the late 2000s. Despite the widespread belief that these early snakes have long been extinct, unverified sightings of snakes 50 feet and up to 150 feet are still reported in South America.

Anacondas like to swim in rivers, making it difficult for researchers to estimate their length. Besides, their ability to remain partly hidden underwater makes it difficult to find and accurately document a specimen that exceeds the current world record.

The largest documented anaconda to date was almost 28 feet, with a girth of 44 inches. It was not weighed at the time, but scientists estimate that it must have weighed over 500 pounds.

There is a misconception that anacondas are the largest among all snake species. However, the fact is that while they are some of the largest snakes in the world, they are the heaviest in weight and may not be the longest. They are also often mistaken for their Eastern Hemisphere cousin, the reticulated python.

The Asiatic reticulated python holds the world record to be the longest snake ever measured, at 33 feet. The anaconda, however, is considerably heavier than the reticulated python. A 20-foot anaconda will weigh more than a 33-foot reticulated python! As a result, anacondas are considered the largest (i.e. the heaviest).

Anacondas are primarily found in tropical areas of South America, although they have also been found in grasslands, as well as in Florida.

Anacondas are primarily found in tropical areas of South America, although they have also been found in grasslands, as well as in Florida.

Geographic Location

The anaconda lives throughout tropical South America, Central America and east of the Andes, mainly in the Amazon and Orinoco basins. It is also found in Trinidad and the African savanna.

There are four distinct species of anaconda.

There are four distinct species of anaconda.

Species

The species is variable in colour and size, and not all anacondas are huge. However, two types are well known (green and yellow anacondas), while two other species (Beni or Bolivian and dark-spotted anacondas) are more recent discoveries.

  • Green anaconda: Scientifically named Eunectes murinus, it is dark green, with black oval patches on its back. This dark green pattern blends the snake well with the dense wet vegetation of its habitat. It is the heaviest among all giant snakes – an adult can grow to more than nine metres in length.
  • Yellow anaconda: The yellow anaconda, scientifically named Eunectes notaeus and formerly called Boa murinus, is true to its name. It is mostly yellow with black spots. It is much smaller than the green anaconda and reaches lengths of 10–12 feet. Its habitat includes swamps, marshes, bush-covers, riverbanks and streams. It can be found in Argentina, Paraguay, southeast Bolivia and Brazil.
  • Beni or Bolivian anaconda: This anaconda is scientifically named Eunectes beniensis, and its appearance is similar to that of the green anaconda.
  • Dark-spotted anaconda: Scientifically named Eunectes deschauenseei, this anaconda is brown with dark brown or black spots.
Anacondas are nocturnal hunters who are solitary outside of mating season.

Anacondas are nocturnal hunters who are solitary outside of mating season.

Behaviour and Diet

Anacondas are primarily nocturnal and can move quickly in the water. They are constrictors, so they squeeze their prey before consuming it.

Do Anacondas Bite?

Just about every species of snake on earth has teeth. Anacondas' teeth are for chewing. However, to hold onto their prey and prevent it from escaping, they rely on their enormous size and power. It is possible to be bitten by an anaconda, but the bite itself would not be fatal.

Hunting

Like all snakes, anacondas are carnivores (meat eaters) and mostly hunt at night. While some snakes use poison to kill or paralyze their victims, anacondas are non-venomous and kill by constriction (squeezing). This means they coil their large muscular bodies around their victim and squeeze until the prey suffocates.

They lie submerged in water, with only a small part of their head above the surface. They also often lie in wait upon the branch of a tree and come surging down to catch animals which come for a drink.

They often find it convenient to drown their prey by dragging them underwater rather than suffocating them by constriction. With their sharp teeth and powerful jaws, they grab the victim, which may be drowned or squeezed to death. Like all snakes, they swallow their prey whole, starting with the head.

Their top and bottom jaws are attached with stretchable ligaments that allow the snakes to swallow animals wider than themselves. Sometimes, when they hunt on land, they move rather slowly and must rely on stealth and the element of surprise to catch their unsuspecting prey.

Diet and Digestion

Anacondas feed on birds, deer, pigs, frogs, dogs and large rodents such as capybaras and agouti. Fishes are the largest part of their diet. Occasionally, they have been known to attack turtles, jaguars, other snakes and caiman (a relative of alligator).

The anaconda has a very slow digestive system. After a big meal, it will rest for several days while digestion occurs. Many anacondas will not eat again for several weeks or even months, depending upon the size of the last meal. One captive anaconda is on record for fasting for two years!

Once the food is inside the snake, it must be digested quickly before it rots inside the snake's guts. If a snake cannot digest its prey before the bacteria, it will be forced to get rid of it. If the snake cannot spit it out, it may die of food poisoning.

Anacondas give birth to living young, as many as 100 neonates at a time.

Anacondas give birth to living young, as many as 100 neonates at a time.

Reproduction and Lifespan

Anacondas give birth to living young, and gestation is about 6–7 months. Sometimes as many as 100 may be born, but most often, 20–40 baby snakes, about two feet in length, are born at a time.

The young are called 'neonates'. They can hunt and care for themselves soon after birth but are pretty much defenceless against large predators and often fall prey to them. So female anacondas have been known to eat their offspring.

Anacondas live about 10 years in the wild and up to 30 years in captivity.

Interactions With Humans

Stories about the enormous size and awesome man-eating qualities of anacondas are exciting but not usual. Anacondas in the jungles of South America can grow so big that they can swallow a grown man, but they seldom attack humans. Incidents of anaconda attacks, although confirmed, are rare because anacondas live in places where humans do not live.

The greatest threat to the anaconda is humans. Many local people kill these snakes out of the fear that they are man-eaters. However, in most instances, if an anaconda senses a human in the area, it will retreat in the other direction.

Conservation

Anacondas face persecution and habitat destruction in the forms of hunting for illegal international pet trade and deforestation.

Although anacondas are not yet considered endangered, some groups have begun taking conservation efforts seriously. You can support the conservation of anacondas by donating to or volunteering for organizations that protect wildlife, such as the Center for Snake Conservation, or that fight deforestation, such as Amazon Watch.

Sources

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

Comments

sebastian on December 02, 2015:

thank you for the the information yo!!!!!!!

I didn't know some of anaconda stuff!!!!!!

a.v. on May 07, 2012:

The anaconda python looks so large and so big thanks for the information about it!!!!!!!!!!!!!!!!!

brandon on May 02, 2012:

sweet i love these snakes

robert on April 30, 2012:

Are you 100% sure that they can swallow an average man?

STHASH on April 20, 2012:

I AM NOT SCARED OF SNAKE BUT ANACONDA YOOOOOO

pooja ghosh on March 29, 2012:

it is fantastic

Jordan on March 12, 2012:

Anacondas ROCK !!!!!!

sam on March 12, 2012:

me to its awesome!!!!!!!!

carlos on March 12, 2012:

im using this to get an A.

lil mama on March 10, 2012:

i don't mind snakes but i am really scared of an anaconda

Firemike on February 28, 2012:

I knew it!!! Anacondas are the largest snakes in the world, not the pyranese rock python. YAY I WON!!!!!!

janet on February 24, 2012:

how does their digestive system work?????????????

Tootie 1224 on February 19, 2012:

Woah,this was great and the comments were halarious

Yola's on February 19, 2012:

I get terrified just by looking at them huge snakes. I am deathly afraid of them more than anything else!

jithin thomas on February 11, 2012:

good better best

logan on February 09, 2012:

cool

ren on February 03, 2012:

very good information provided

mack4 on February 03, 2012:

they looks so small by pics, i have seen the bigger ones before...

muthus on January 31, 2012:

very amazin

ck on January 29, 2012:

these s thing are huge.............damn

chutki on January 25, 2012:

I think snakes are become a real friends . so i trust only animals ,i want to become a friendship with snakes .......that's all

psalmson on January 24, 2012:

anaconda very big and long living snake in the world

craig holliday on January 23, 2012:

i have a green anaconda about 9ft long very nasty

simran george on January 19, 2012:

i hate anaconda.................

wilbert on January 18, 2012:

what a snake....!!!!!!!!

Kistaiah on January 17, 2012:

Nice to see it But fear to go nearrrrrrrrrrr

trini on January 16, 2012:

in trinidad it have a tis lil swamp like lake where they are believe to live cause farmers around the area does get up and find there goat or sheep and sometimes a cow missing ....but it have this local legend dat its a beast livin in the lakw but its the snake cause many fisher men saw it moving in the water

sniper on January 15, 2012:

wow its big but i dnt'n like that kind of snake maybe they will kill me';'

ContainerZero on January 11, 2012:

Holy Snakes that's a big one!

mark on January 04, 2012:

O M G,,,,,

Hussein on December 26, 2011:

I wish the green anaconda lived with me

dejin on December 14, 2011:

i love snakes especialy anaconda...

Kenadi on December 12, 2011:

I never want to see one of those!!!!!

Kenadi on December 12, 2011:

Scarry

rose on December 11, 2011:

Is it really true about that snake?

Term Paper guy on December 08, 2011:

Im doing a term paper on dangerous animals and this really helped thanks dude

little mama on December 06, 2011:

i would love t see them in persn but justfar away s that i don't get bitten

alice on December 05, 2011:

wow, t didn't think this snake is that big. it really isn't.

hussein on December 02, 2011:

I it very big but horrible

Falk rani on November 27, 2011:

I love snake nd i want to see snake

shabir on November 24, 2011:

wowwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww

samri on November 16, 2011:

wow cool :O there soo big.

i did a project about ANACONDAS

anaconda member12354 on November 14, 2011:

ilove the green anaconda

snakelover334 on November 13, 2011:

I love anacondas! They are so awesomely amazing. ANACONDAS 4 THE WIN! GO ANACONDAS! I wish I had a pet anaconda. Well, basically any sort of snake, but anacondas are the best. Yellow Pythons are the second best:)

nailea on November 13, 2011:

they are awesome and creepy !!!! lol

NEISHA on November 12, 2011:

WHY DO PEOPLE EVEN LIKE ANDACONDAS THEY ARE SO BIG AND SLITHERY. IF I GOT BIT BY ONE I WOULD DIE SO I HOPE I DON'T RUN INTO ONE,OTHERWISE ILL PASS OUT. {I HAVE ALREADY RAN INTO A MAN WITH A PYTHON THAT HE FOUND BUT GUESS WHAT IT DIDN'T BIT

laverna on November 08, 2011:

I have a yellow anaconda she is so beautiful and she is very very sweet.watching them eat is insane and awesome but very dirty there is a lot of blood after they eat so its a good thing they eat in the water it makes it easier to clean.but I also own a ball paython and a savannah monitor.

Emph on November 08, 2011:

Woooow, at first I thought it was Rambo. or maybe they are brothers

andrew on November 07, 2011:

I get the chills

bla bla on November 02, 2011:

that is so amazing =p

chibuzor on October 31, 2011:

d information is quite cool,i jst wish i lived in a country where it cn be found.i think i won't get satisfied until i see them with ma own eyes! Very very big i will definitely not wish a friend this in a nightmare!!

Randall on October 30, 2011:

Its hilarious to read the comments made by all the teens who have visited this page.

BOATENG on October 29, 2011:

I think this creature should be part o the ancient animals like dinosaurs because it is a very huge snake

Kyalo derrick muli on October 13, 2011:

Wow! I lyk it, the snake is lyk ma pet cz i c snakes daily n sometimes even bigger dan that!!! i'm in real luv wid snakes!!

joe on October 02, 2011:

holy crap big snake

James on September 29, 2011:

I have seen bigger snakes than that

pablo on September 23, 2011:

I went to central America to visit family and friends. They do have a taste for man. The local Policia killed a Anaconda when I was there because the snake consumed a local fisherman. They had to cut open the snake to retreive his body. The fisherman looked like a chicken bone.

willy on August 29, 2011:

Just seing a picture of them scares me like crazy!!!

iRINE pINK on August 20, 2011:

cONGS.

gO AHEAD!

Snakeman45 on July 22, 2011:

Yes these big snakes are my entire life. that's al i do is explore these snakes and their habtit. i actually know a guy in the amazon who can book you trips to hunt andaconda likes these. and im gonna go get me one that beats the world record.!

Jazzielovezyuh on May 23, 2011:

wowza i have a python an its like 24ft long but i really want to see an anaconda :)))

sbongumusa on March 03, 2011:

damit snakes are not kwl at all i hate them smtyms but anaconda wolw they are so amaizing

richie on February 27, 2011:

i've held 1 b4!!

i h8 them they eat people

santu on October 26, 2010:

That's a detailed nice information on anaconda .Thanks for the information.

shermar on October 25, 2010:

biggggggggggggggggggggggggggggggggggggggggggggggggggggg

AnDUHconDUH! on September 25, 2010:

I own a tank that weighs 3000 lbs how many andacondas can you fit?

tanny on September 23, 2010:

After seeing these images, i checked my back to make sure there was no snake behind me.

regina sibayan on September 15, 2010:

wow i can't believe it!

purple2000 on August 23, 2010:

ooooh i want 2 know more!!!!!!!!!!!!!!!!!!!!!!!!!!

max on August 20, 2010:

awesome

ymca on August 19, 2010:

very good information pictures too

Avery on July 14, 2010:

So cool. I love anacondas. I want a pet one too

chetan on June 22, 2010:

I LIKE SNKES VERYYYYYYYYYY MUCH AND want to make friendship with snakes

kb on June 03, 2010:

i love snakes,pliz me all the info.please

kahleo on May 02, 2010:

dang ,that thing huge dawg ,freaking huge

Ghiggins549 on April 27, 2010:

Crap, those guys are insane to knowingly go into the territory of those creatures to catch them. But worth it I bet.

Snakelover17 on April 13, 2010:

ive always been in love with those giants snakes that's why im going whit 10 of my friends in one of the jungles where we can find so we can take pictures of them !!! ( ITS GONNA BE 5 LONG MONTHS OF FUN !!!!! )

mAISARAH on April 08, 2010:

wow so big lolooooooooooooooooooo

Kim on March 06, 2010:

Yo! They look so freaky...WOW!

AnacondA on February 21, 2010:

no way man i don't want to see 'em yuyyyu yacks hate reptiles

jungli on February 19, 2010:

I love this pretty creature if any one intrested to see them contact me i have got few

biggest snake in world on February 11, 2010:

I am in LOVE with all animals and fascinated by them.All the best

maryam on February 05, 2010:

thnaks a lot because of this page i am getting A++

nanda on January 27, 2010:

oops............they are toooooooooooo scary.bt i wish i could see one.

katie on October 26, 2009:

its pretty cool

nikeya carter on October 14, 2009:

i just lov them

deepa rana on September 04, 2009:

i rrrrrrrrreeeeeealllllllyyyyyyy enjoyed it though they r toooo scaryyyyyyyyyy!!!!!!!! wel, information r very nice thanks

abhishek on August 11, 2009:

oooooohhhhhh!!!!!!!!! they r so scary !!!!!!!!!!!!!!

Nijah Douglas on August 04, 2009:

very big huge i like them very scary and would not want to get kill by it

VALERO on April 16, 2009:

HOLY SHIT!IT LOOKS LIKE DR. SUZY'S WORST NIGHTMARE..

AndyBaker from UK on April 01, 2009:

I don't mind snakes at all, but I wouldn't want to get too close to a really big one.

scott on March 20, 2009:

tom hanks!!!!!!!!

rockstar on February 25, 2009:

that's preeeety spoooooooky

Christine Mulberry on February 11, 2009:

Ugh, adds yet another reason to "don't go in the water". shudder! Good information, I didn't realize they were really water snakes.

AMIGO.A on February 11, 2009:

THEY ARE FEARFUL BUT I WOULD LIKE TO SEE ONE ON MY OWN VISUAL EYES

RICHARD on February 09, 2009:

W0W I WANT TO SEE 1 OF AN anaconda

KARINA on February 09, 2009:

I WISH I COULD BE A SCIENTIST!!!! JUST THAT I DON'T WANNA GET BITTEN!!! AAAAAAAAAAAAAAAAAAAAAAAAAH

seminole on February 09, 2009:

that is so grooss

NDBEES from DEVON on February 05, 2009:

I couldn't eat a whole one. I'm watching my figure.

erica on February 04, 2009:

i am scared