River Monsters: 8 largest freshwater fishes in the world

The deep blue sea isn’t the only place where large behemoth fishes can be found. Our freshwater rivers and lakes are home to some of the world’s largest fishes that can easily kill a cow. While the majority of river monsters are smaller than their salty ocean counterparts, they can grow large and reach impressive sizes. In the wild, these freshwater fishes can reach the size you cannot imagine. Some of these fishes are legal to be kept as pets. But, they need large tanks with plenty of food. If you are into fish-keeping and are fascinated by the world of freshwater fishes, we have brought you a list of some of the world’s largest freshwater fish in the world. 

#1 Beluga Sturgeon – a freshwater drum

Beluga Sturgeon is probably the largest freshwater fish in the world. It can reach a maximum length of 20-24 feet and weigh anywhere around 2500 pounds. This is a true river monster and is native to the Caspian and Black Sea basins and estuaries. They boast a shark-like tail, and the species is estimated to be 200 million years old. They are said to be on the brink of extinction because they are hunted for harvesting the world’s most expensive food item – the Beluga Caviar. 

#2 White Sturgeon 

White Sturgeon is native to the North American rivers and the Pacific estuaries. They can be easily identified by their flat, shovel-like head and scutes. White Sturgeons can grow 20 feet in length and weigh up to 990 pounds. They are one of the biggest freshwater fish predators. They are covered in bony, hard plates called scutes that protect them from other predators. Despite their size and weight, White Sturgeons are incredibly flexible, making them quite agile in the water. What’s interesting is that a female White Sturgeon can release about 3 million eggs at once. 

#3 Giant Freshwater Stingray 

The giant freshwater stingray is one of the lesser-known species of stingrays as compared to its oceanic counterparts. Found in Thailand estuaries and rivers, freshwater stingrays can grow up to 16.4 feet in length and weigh as maximum as 1300 pounds. They are extremely deadly because of their long, stinging tail. They can kill a fully grown adult in a single hit. The sad news is that this true blue river monster has been affected badly due to pollution and interference with its natural habitat, with scientists predicting that the species may not last long. 

#4 Wels Catfish 

Wels is a gigantic species of catfish native to the waters of Central and Eastern European rivers and basins. It is considered an invasive species, and to control their population, they were introduced as a sporting fish in many regions. It can grow up to 16 feet long and weigh a massive 660 pounds. Due to its large size, it got the nickname “The European maneater,” “The Ebro Monster,” and “Man-eating Catfish.” In reality, they are far from a maneater. Their diet includes eels and other fishes, and sometimes ducks and goose. 

#5 Paddlefish 

Paddlefish is a critically endangered freshwater fish that can grow massive in the wild. They are easy to recognize because of their paddle-shaped snout. They can grow up to 10 feet long and weigh 660 pounds. They can be found in freshwater bodies of Chin and South America and some lakes in Canada. Paddlefish cannot be easily spotted because they prefer murky waters. 

#6 Mekon Giant Catfish – giant grey fish

The Mekon Giant Catfish is one of the biggest freshwater fishes in the world that can reach 10 feet in length and up to 650 pounds in weight. They are native to the Mekong Basin in Southeast Asia. Currently, their wild population is under threat due to overfishing and habitat loss. This aquatic behemoth has no teeth and no whiskers. They resemble a shark because of their great size and lack of outstanding barbels. 

#7 Arapaima 

Arapaima is one of those freshwater monsters that people prefer to keep as pets. They are native to South American rivers and lakes. Fishkeepers breed them in captivity and sell them to hobbyists. They have a unique identification – orange or bright red flecks towards the tail area. Arapaima can grow over 10 feet long and weigh up to 400 pounds. They are surface breathers, meaning they will come to the surface to breathe. Arapaimas are scaly giants and part of the pre-historic era. ]

#8 Alligator Gar 

The last is the Alligator Gar that is native to the Americas. Alligator Gars can weigh up to 330 pounds and grow a maximum of 10 feet in length. They are also a part of the pre-historic era and are known for their unique alligator-like appearance. They look like an alligator when viewed from the top. Gars are peaceful freshwater fishes and pose little threat to humans. 

Hopefully, the list will give you an idea about some fish species that are the true giants.