Black caiman, electric eel, vampire fish… are some of the ferocious aquatic monsters found in the Amazon River, one of the largest rivers and home to many of the world’s most dangerous animal species.
1. Black Caiman
The Amazon River is located in South America and is known for being home to many gigantic and dangerous animal species. The black caiman is one of the fierce aquatic monsters that inhabit this river. A black caiman can grow up to 6 meters long, with a large skull that is heavier than that of the Nile crocodile. As a top predator in the Amazon, the black caiman can eat anything nearby, including piranha, monkeys, deer, catfish, and even anacondas. In 2010, biologist Deise Nishimura lost a leg while fighting with a black caiman after the creature had hidden under her boat for eight months.
2. Green Anaconda
The green anaconda is the largest snake in the world. Female anacondas can be larger than males, reaching lengths of 9 meters, weighing up to 250 kg, and having a body diameter of 30 cm. This species is non-venomous; instead, they use their immense muscular strength to constrict prey such as deer, caimans, and even jaguars. They typically inhabit shallow waters that allow them to hide and prefer areas along the Amazon River’s tributaries.
3. Arapaima
This giant carnivorous fish lives in the Amazon River and nearby lakes. Arapaima are often found near the water’s surface because they need to breathe air in addition to absorbing oxygen through their gills. Arapaima can grow up to 2.7 meters and weigh around 90 kg. They are so aggressive that even their tongues have teeth.
4. Giant River Otter
The giant river otter is a prime example of the weasel family. Adult male otters can grow up to 2 meters long from head to tail. This species primarily feeds on fish and crabs. They often hunt in groups of 3 to 8 and can consume up to 4 kg of food each day. Additionally, these otters can attack and eat anacondas and caimans. They are also considered one of the most formidable predators in the Amazon and are nicknamed the “wolves of the river.”
5. Candiru
The Amazon River not only produces gigantic creatures but is also home to tiny yet terrifying beings. The candiru is a small parasitic freshwater fish known for its ability to swim into the urethra of anyone who dares to urinate in the river. One man had to undergo surgery to remove this creature from his urethra while it was attempting to enter his testicles. Candiru often use spines to attach to larger fish and feed on their blood.
6. Bull Shark
Bull sharks typically inhabit freshwater areas and are found in deep waters along the Amazon River, such as in Iquitos, Peru, located 4,000 km from the ocean. This species can sense changes in water salinity and adapt to new environments. They grow to about 3.3 meters and weigh up to 312 kg. Like other sharks, they have numerous triangular-shaped sharp teeth and powerful jaws capable of exerting a bite force of up to 589 kg. Bull sharks are considered one of the most dangerous shark species in the world.
7. Electric Eel
The electric eel resembles a catfish more than an eel. This electric eel can grow up to 2.5 meters long and generates electricity from special cells called electrocytes located along its sides. The electric shock can reach 600 volts, five times the voltage of a standard outlet in the U.S., enough to incapacitate a horse. Multiple shocks from this creature can cause heart failure or respiratory distress in humans. When attacked by an electric eel, an average person can be stunned and drown. Electric eels locate their prey by producing 10-volt electric pulses before stunning and killing it with more powerful currents.
8. Red-Bellied Piranha
This fish primarily feeds on decaying animal carcasses. They reach about 30 cm in length and swim in large schools. The red-bellied piranha has sharp teeth, and their interlocking jaws make it easy to rip flesh from prey. Groups of red-bellied piranhas can focus on an unfortunate prey and dispatch it quickly within minutes. However, attacks on prey are quite rare and usually occur when they are very hungry or provoked.
9. Payara (Vampire Fish)
Payara is a highly aggressive predatory fish capable of swallowing prey that is half its size. Its primary diet consists of piranha. Their name comes from two fang-like teeth that grow from the lower jaw, measuring 15 cm in length, used to pierce through prey after an attack. The upper jaw of the fish has special grooves to avoid piercing from its own fangs.
10. Pacu Fish
Pacu fish are creatures with teeth resembling human teeth. Unlike the other species on this list, pacus are omnivores, preferring fruits and nuts. However, these fish can instill fear in many men due to their ability to bite off their testicles. A man in Papua New Guinea died after being bitten by a pacu that severed his testicles.
