What Can Kill You In The Amazon River (Would You Visit)?

What can kill you in the Amazon River?

The Amazon rainforest is one of the most important, gigantic, and diverse ecosystems on earth, providing the perfect habitat for amazing yet dangerous creatures such as the Jaguar and the Poison Dart Frog for example. But in the depths of the Amazon River, the largest river in the world, unbelievable creatures so so terrifying that they make Sharks look like a good and relaxing swim in the sea (and by the way, there are sharks in the Amazon River).

1) Black Caiman (Jacaré-Açu)

What Can Kill You In The Amazon River?

This crocodilian is the largest of South America and along with the American alligator one of the biggest on earth. A relentless carnivorous reptile that lives in lakes, slow rivers, and flooded savannas in different freshwater habitats of South America.

The Black Caiman is gigantic, growing at least to 5m (16 ft) and possibly up to 6m (20ft). Although, some people from the riverside population in the Amazon report that already saw Black Caimans (known as Jacaré-Açu) more than 9 meters long.

It’s just reporting, but they should not be completely ignored since the native population is who has the most direct contact with these animals, in the depths of the Amazon forest. A Black Caiman is an animal that can absolutely kill you in Brazil, but the odds of being attacked by one of these crocodiles are very low.

A Destructive Attack (Which Rarely Leaves Any Survivors)

When such an animal bites someone, the victim hardly survives. On New Year’s Eve 2010, in Mamirauá, São Paulo biologist Deise Nishimura had an unwanted surprise. While she was cleaning fish on the edge of the houseboat where she lived, she was dragged into the water by an alligator more than 5 meters long. Despite the slim chance of survival, she decided to fight for her life.

“At that time, I thought I had already died, that was it. But then I thought: what is the most sensitive part of an alligator? I put my hand on his head and I found two holes, I don’t know if it was his nose or his eye, and I stuck my fingers in like that, really hard, and squeezed really hard. That’s when he let go of me, and then I realized that I was already without my leg”, recalls the biologist.

Deise swam to the edge of the house but couldn’t climb it. She had to climb a log to get out of the water. Exhausted, she screamed for help. But there was no one around. So she crawled into the radio room and called for help. “Fifteen minutes later, the reserve staff arrived. They made tourniquets on her legs and took the biologist to Tefé. In the hospital, an hour later, the doctor was amazed.”

She is a very rare case of surviving the attack of a black caiman. Deise told her survival story in this TEDx Talk. It’s in Portuguese but there are subtitles. It’s an incredible story that definitely worth the time to watch.

2) Anaconda (Sucuri)

If you ever watched the movie Anaconda in the ’90s then you know what I’m talking about. Although the movie exaggerates the behavior of the snake, there are gigantic snakes that can kill and eat humans here in Brazil. It’s very rare, but it happens. Know in Brazil as “Sucuri”, the Anacondas are the biggest species of snakes that can be found in the Americas, reaching up to 10 meters in length.

A Hell of A Bite (And Hug)

Anacondas are not poisonous, but the powerful bite stuns the prey, which is quickly enveloped by the snake’s strong and robust body. These huge snakes live close to rivers and lakes and have a semi-aquatic habit and. Although slow on land, they are very agile in the water: Eunectes, the name of their genus, means “good swimmer”. Usually, they wrap themselves around the prey that is taken to the water, where it drowns.

The strong “hug” of anacondas can also kill their victims by asphyxiation – each time the prey expires, the snake tightens until it stops breathing completely. Anacondas are all over the country, usually in flooded areas. Unfortunately, by fear and greed (their skins value a lot of money), a lot of people still kill this beautiful animal even knowing that the chances of killing a human are very low.

3) Arapaima (Pirarucu)

This gigantic and dangerous animal lives in the mysterious waters of the Amazon River, making victims in the animal world as well as humans. Arapaima, better known as “Pirarucu” or even “Paiche”, is a gigantic carnivorous fish that lives in the Amazon in nearby flooded regions. Encased by scales that look like real armor, the Pirarucus seem to make light of the fact that they live in piranha-infested waters. Furthermore, they are very effective predators, feeding on fish and one ocisionally even on birds.

Pirarucus tend to stay close to the surface, as they need to breathe surface air through their gills, and make a characteristic coughing sound when they emerge to breathe. The animals are really gigantic, reaching 2.7 meters in length and weighing more than 100 kg. These fish are so cruel that even their tongue has teeth. Believe me: Pirarucu’s tongue bones are so hard and rough that it is used in the Amazon as a cooking tool, to grate grains, including guarana.

The animal’s tail attack is also fierce, being responsible for the death of at least one fisherman. The fisherman was hit in the abdomen region and, according to information that reached the Secretariat of Rural Production of Amazonas, one of the ribs would have broken and hit a vital organ, causing him to die.

4) Giant Otter (Ariranha)

The giant otters are giant otters and another great reason to never swim in the murky waters of the Amazon River. They are the largest specimens of the weasel family, with adult males reaching up to two meters in length from head to tail. They are carnivorous animals and their diet consists mainly of fish and crabs. Otters generally hunt in family groups of 3 to 8 members, and can eat up to 5kg of food per day.

Although they look nice and “cute”, don’t be fooled. They are fierce hunters and have been seen destroying and eating anacondas. Recently, a family of giant otters was seen devouring a 6-foot-long alligator! Unfortunately, their numbers have been decreasing in recent years, mainly due to human intervention. They are among the most capable predators in the Amazon rainforest, hence their local name “river wolves.”

5) Toothpick Fish (Candiru)

The Amazon River does not just produce giant animals. There it is also possible to find small creatures as terrifying as an Anaconda. A clear example of this is Candiru, a small parasite that is the animal I am particularly afraid of among everyone on the list.

Candiru is a small, freshwater parasitic fish, with stories that are simply terrifying to any man. It turns out that the little fish is famous for getting into the urethra of anyone foolish enough to urinate in the river (the urine attracts them), and they get lodged in the urinary tract because of the spines that run along the back.

These terribly painful stories are told (and feared) by residents and also confirmed by hospital reports, of men needing surgery to remove a Candiru from his urethra, who had also tried to dig through his testicles! However, it’s worth noting that the Candiru has a preference for attacking other fish, attaching itself to the gills of larger fish with its spines and feeding on its host’s blood.

6) Bull Shark (Tubarão Touro ou Cabeça Chata)

What Can Kill You In The Amazon River? Bull Sharks.

These large stout sharks are found in both salt and fresh water. Here in Brazil, it’s common to find Bull sharks in the amazon river that can easily kill humans (as if they needed more wild animals over there lol). The Bull shark has been recorded in rivers hundreds of miles from the sea, as in the case of the Amazon River in Iquitos, Peru, almost 4,000 kilometers from the sea.

These sharks have special kidneys that can sense the change in water salinity and adapt accordingly. And you don’t want to swim in a river with such an animal: it’s very common for bull sharks reaching over 3.5 meters in length and weighing almost half a ton.

Like many sharks, they have multiple rows of sharp teeth and immensely powerful triangular jaws, with a bite force of 589 kg, making them one of the shark species that most attack humans (along with the tiger and white sharks). Combined with their relentless aggressiveness with their habit of living close to densely populated areas, this has led many experts to identify them as the most dangerous sharks in the world.

7) Electric Eel (Enguia Elétrica)

What Can Kill You In The Amazon River? Electric Eel.

The Electric Eel is another beautiful (and killer) animal that lives in the waters of the Amazon River. This species is more like catfish than eels, but they are still extremely dangerous animals responsible for many accidents, sometimes fatal. These critters can grow up to 2.5 meters in length and can produce shocks of electricity from specialized cells called electrocytes, located at the bottom.

These shocks are very powerful and can reach up to 600 volts, five times the charge of an average American socket, enough to bring down a horse. While one shock isn’t enough to kill a healthy adult person, multiple shocks can cause heart failure or respiratory failure, and it’s common for people to get dizzy and drown after an eel attack.

Many of the reported disappearances in the Amazon region have been attributed to eels, but this is unlikely. Fortunately for us humans, eels tend to feed on fish, amphibians, birds, and small mammals. The hunting technique is very advanced: they locate their prey by sending small 10-volt shocks and then killing them with larger shocks.

8) Red Piranha (Piranha Vermelha)

One of the most famous and terrifying animals that can kill you in the Amazon River is the Piranhas: so well known that they are “protagonists” in several Hollywood movies. As a rule, these animals eat carcasses and wounded animals but don’t be fooled, attacks against humans and healthy prey also happen.

These animals can be more than 30 centimeters long and swim in large groups, so they can kill even large animals such as cattle and capybaras. Like all piranhas, red ones have extremely sharp teeth, a line in each of their powerful upper and lower jaws. These teeth are interlocking, making them perfect for tearing the flesh from your fangs.

Its fearsome reputation mainly comes from its fierce and quick group attacks, in which the piranhas devour their prey and leave it to the bone within minutes. These attacks are rare, but they happen, usually as a result of extreme hunger in unbalanced environments, provocation, or pre-existing injuries to humans or animals that end up drawing the attention of the Piranhas.

9) Vampire Fish (Payara)

I make it a life rule to avoid going near anything with the name “vampire” attached, whether it’s dangerous or not. This has kept me healthy and able to see my reflection in mirrors for 27 years and count. The “vampire fish” is no exception. Payaras are absolutely fierce predators, capable of devouring fish up to twice their size. Bearing in mind that these animals can grow up to 1.2 meters in length, this is no easy task.

Much of their diet is made up of piranhas (yes, this fish eats one of the most feared fish in the world), which should give you an idea of ​​just how tough these toothy enemies can be. Its name vampire fish comes from the two tusks that sprout from its lower jaw, which can grow up to 6 inches in length! They use the fangs to literally impale the prey after violently launching themselves at them. Their teeth are so big, in fact, that they have special holes in their upper jaw to keep them from sticking themselves.

10) Pacu

What Can Kill You In The Amazon River? Pacu Fish.

In this list, I brought several fearsome predators, great monsters that inhabit the murky waters of the largest river in the world. But of all, the two I fear the most are Toothpick Fish and Pacu, for very specific reasons… Yet another animal that will be far more terrifying to men than to women, the Pacu is a larger relative of the piranha, known for its distinctive human teeth. Unlike most of the creatures on this list, the pacu is actually omnivorous, and a good part of its diet is made up of fruits and nuts.

Unfortunately, for some Pacus, “nuts” may not just mean things that fall from trees. Yes, that’s right: Pacus are accused of occasionally biting swimmers’ testicles, with reports of men in Papua New Guinea being killed by pacus after the fish apparently simply mistaken their genitalia for an easy snack… Oh, and don’t worry if you can’t go to the Amazon to see these monsters chomping on their “nuts” because they’re already spreading to Europe too 🙂

Related Articles

Sharks in The Amazon River: Are There Sharks In The Amazon River?
Black Caiman: Black Caiman: The Monster Of The Amazon River
Swim in The Amazon River: Can You Swim in The Amazon River? (Would You?)


What’s up! I’m André, a Brazilian born and bred living in the South of Brazil in a little city called Guarapuava. I’m passionate about traveling and knowing different cultures and that’s why I love to share useful information about the Food, Travel, Facts, and Culture of my beloved country, Brazil.

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