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Scariest Animals in the Amazon

  |   Wildlife & Flora

As one of the most biodiverse areas on Earth, the Amazon is home to its fair share of creepy crawlies and monstrous creatures. In honour of Halloween, we’ve profiled some of the most fear-inducing predators that call this rainforest home. From those that pose considerable danger, including venomous snakes, spiders and centipedes, to the gentler but no less scary-looking, piranha, caiman and arapaima, read on to discover what terrifying surprises lie in wait! You may find this article sufficient to fuel your nightmares, but if you embark on an Amazon cruise you may be lucky (or unlucky?) enough to spot some of these creatures in real life! Just be sure to watch your step…


7 Scary Animals in the Amazon


green anaconda snake

1. Green Anaconda Snake

The Amazon is home to a whole range of terrifying and dangerous snakes, from the highly venomous pit vipers to the ferocious South American rattlesnake. But none is perhaps more intimidating than the huge green anaconda. Reaching lengths of over 30 feet and weighing more than 500 pounds, it’s the largest snake in the world. The good news is that they are not venomous! But instead they use their formidable muscle power to constrict and suffocate their prey before swallowing whole without chewing, regardless of their victim’s size. They are particularly agile and stealthy in the water and lurk in the Amazon River in wait of anything they can strike and overpower, which includes jaguars, caimans, turtles, wild pigs, deer and even humans. The large size of its meals means that these snakes don’t need to feed often, sometimes lasting months between meals, but we still recommend staying well clear!



red-bellied piranha

2. Red-bellied Piranha

This fearsome looking fish has a reputation for “feeding frenzies” whereby large schools swarm around prey stripping all the flesh from the bones within a matter of minutes. There are plentiful stories of large mammals and even humans being targeted and eaten alive in the water, as depicted in several well-known Hollywood movies. With its razor sharp triangular-shaped teeth, powerful jaw and fearsome looking red eyes, the piranha certainly looks pretty terrifying. But you’ll be glad to learn that their aggressive reputation is largely overstated, especially when it comes to people. In actual fact, red-bellied piranha are primarily scavengers, feeding mainly on other fish (usually already dead or dying), insects and plant life. They are actually more more innocent than they seem! You can swim safely with piranha in most places in the Amazon River. At the very most you may just feel a light nibble on your toes or fingers. Piranha also make a delicious meal and on an Amazon cruise you may have a chance to fish for them. So perhaps they’re the ones who should be scared of us!



electric ell Amazon River

3. Electric Eel

Not actually an eel, but a type of knifefish, this shocking creature is capable of generating up to 600 volts through its elecrocyte cells, five times more electricity than in the standard wall socket. It usually only uses small amounts of electricity to stun its prey of choice, but when feeling threatened it is capable of releasing stronger and multiple shocks that can endure minutes on end. Residing in the murky depths of the Amazon River, the electric eel feasts on invertebrates, fish and small mammals. There have been numerous reported incidents between humans and electric eels often involving unpleasant and unexpected shocks. The electric eel is largely avoided by locals as it can still shock up to 8 hours after its death. 



amazonian giant centipede

4. Amazonian Giant Centipede

Another particular creepy-looking inhabitant of the Amazon jungle is this giant centipede, the largest centipede in the world, growing to lengths of up to 30 centimetres and sporting no less than 46 legs. These creatures can be spotted running swiftly along the forest ground or skilfully negotiating tree trunks and branches in search of prey, which can range from insects, lizards and birds, to mice, frogs, snakes and even bats. They are equipped with a pair of modified legs terminating in sharp claws near the head which they use to grab unsuspecting victims, penetrate the skin and inject a highly toxic venom that is fatal to most small animals. Whilst not lethal to humans, if you are unlucky enough to get bitten you’ll certainly know about it as the poison triggers symptoms of localised pain, swelling, fever and weakness. 



amazon bull shark

5. Bull Shark

Believe it or not, the Amazon is also home to the world’s most dangerous shark. The bull shark is huge and very hefty, spanning lengths of up to 11 feet and approaching 700 pounds. It’s capable of adapting to both salt and fresh water environments and has been spotted as far upstream as Iquitos in Peru. They possess enormously powerful jaws and will gorge on just about anything, from sloths to dolphins, turtles to birds, and even member of their own species. The bull shark is aggressive and highly territorial and is thought to be responsible for the majority of coastal attacks on humans due to its preference for shallow waters. Thankfully, it is still a relatively rare occurrence to encounter one in the Amazon River! 




Arapaima Amazon Fish

6. Arapaima

The carnivorous arapaima is one of the largest freshwater fish in the world, spanning 2 metres on average and coming in at over 100kg, though there are also cases measuring a whopping 15 feet. It feeds priamrily on fish and crustaceans, but is also partial to striking down small land animals who happen to be near the shore. It’s tough armour-like scales make it immune to piranhas, whilst a powerful set of jaws make it a pretty fearsome predator all round. Unlike many of the creatures profiled in this list, they don’t pose a threat to humans. In fact, being an important food source for indigenous tribes, they are vulnerable to being hunted by people, so much so that the Brazilian government has banned commercial fishing of the arapaima. However, it still pays to be wary… This fish is thought to be the inspiration behind a local Amazonian legend that refers to an evil spirit said to inhabit the body of a huge scaly fish capable of leaping out of the water and knocking out fisherman in a torpedo-style attack.



Tarantula in the Amazon

7. Tarantula

Anyone visiting the Amazon rainforest can be lucky, (or unlucky) to spot a tarantula, the largest spider in the world. You'll recognize their massive bodies (up to 13 inches across!) by their black and brown barbed hair. They live in burrows in the ground or high in treetop nests. They might look scary, but you don't have to worry, tarantulas are gentle giants. Their bites are not venomous, and in the rare occasion of getting bitten by one, a bite will feel similar to a bee or wasp sting, and has no lasting effects. The hairs covering their body, however, can be extremely irritating to human flesh, so maybe avoid getting too close!



Do you dare to see any of the scariest animals in the Amazon up close? Perhaps other creepy crawlies that did not make the list? Contact us to start booking your Amazon river tour. You can also give us a call 1-888-215-3555

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