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5 Dangerous fish of the Amazon

Last Updated: 01.12.23


In terms of aquatic forms of life, the Amazon shelters over 2,000 species of fish. It is a haven for those that want to explore the fauna of this huge region and discover more about the variety of species that have their home here.

However, not all species of fish in the Amazon River Basin are friendly, obviously. Because the rainforests are untainted, so are the animals that inhabit them. Therefore, in the following paragraphs, we will present you five of the dangerous fish that lie in the waters of the Amazon.

Brace yourselves, as some of the following species of fish are more than just dangerous.


While the name of this species may sound cute to some, they offer a terrific sight, and in some cases, pain to those that happen to come across a specimen of this species. A relative of the piranha, Pacu is a much larger species of fish. Their main – and very scary – characteristic consists of the human-like teeth that can bite off anything from fruits and nuts and to a man’s most precious possessions.

Wearing a pair of fishing pants that are thick enough to block the bite of a fish might be helpful if you plan on diving in the waters of Amazon – a thing that is not recommended. But beware if you are in European waters as well, as this species of fish have begun to spread out of Amazon and into some regions of Europe.



Also known as paiche or pirarucu, Arapaima is a fish so big that it can reach a length of nine feet and weigh up to 200 lbs. You’d have to be a bodybuilder in order to lift this one off the ground. However, you might want to rethink that decision.

First of all, because Arapaima is a species of carnivorous fish that doesn’t even fear the dreadful piranha – a reason why some Arapaima can be found living peacefully in waters inhabited by the latter species. An Arapaima comes equipped with the standard set of teeth that a fish usually has, but we’re not done yet.

The effectiveness of their predatory skills is also given by the fact that they have teeth even on their tongue. That’s why it’s recommended that you just stay away from the Arapaima. The easiest way to spot one is to keep your ears on full focus and wait for a coughing sound that’s distinctive for this species. Because they have to take in oxygen through the gills, they often come to the surface and make that coughing sound we talked about as soon as they emerge from the water.


Payara – the vampire fish

A vampire usually has two really sharp and fairly long teeth – in order to suck blood off their victims. However, this species of fish could easily beat any vampire out there. Why? Because Payara have two long tusks that can get as long as six inches. These tusks grow from their lower jaw and are big even for the fish itself.

Even if a Payara can grow up to four feet long, it’s still not enough for his mouth to be able to hide the tusks we mentioned. That’s why they have two holes located on their upper jaw – so that they wouldn’t impale themselves while taking a break from munching off piranhas.

Sure, you could bring your fishing rod and reel and maybe manage to capture a Payara, but we don’t think you’d be able to get too close to it and take a better look. It’s best that they stay in their waters and are not disturbed.

After all, they’re called the vampire fish – and since we’re afraid of vampires, which are imaginary, there’s no doubt we will run, or swim, away at the sight of a Payara.


This species, unlike our previous entries on this list, is quite small. Nothing to be afraid, right? Well, you should –  you should really be afraid of these, especially if you are a man and love dipping in water.

They are freshwater catfish, but also parasitic. This means that they will feed off of anyone or anything they manage to attach themselves on. Attaching is possible due to the spines that can be found on their back. They usually get nice and comfy by sticking onto the victim’s gills after which they proceed to feed with their blood.

The reason why we said that you should be afraid of such a fish is because there have been some reports of Candiru that have sneaked up the urethra of people that dared… to take a leak in their precious waters.

While most scientists consider that it is highly unlikely for someone to get themselves in such a situation, there has been one case of a man that had a Candiru stuck in his urethra and had to undergo surgery in order to remove the fish from the delicate area. Be careful – keep your pants on!


Red-Bellied Piranha

You’ve seen this species mentioned a couple of times so far but in relation to other species that was actually having them for lunch. However, a school of piranhas is something to be afraid of and one of the main reasons for which you shouldn’t leave your boat if you are on the Amazon.

The fact that they swim in large groups is more of an understatement when it comes to this species. While fairly small, growing only up to 12 inches, these scavengers never hunt alone. Just imagine around forty or so piranha swimming around peacefully, until they sense food and prepare their interlocking teeth for the feast. Speaking of teeth, a Piranha’s mouth is full of very, very sharp teeth, on the lower and upper jaw.

Most of the times, especially in Hollywood movies, this species is portrayed as relying on feeding frenzies. We’re talking about those scenes where someone or something – preferably meat – is thrown in the water and it gets really agitated and bubbly, a sign that they have started their feast.

This, however, occurs only when the Piranhas are starved or only when provoked. Still, you can forget about bringing your fishing boots or any other very resilient fishing clothes as they will probably be ripped off if you encounter a school of Piranha. Stay out of the water!



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