The arapaima gigas also known as the paiche or pirarucu is a true river monster. One of the world’s largest fresh water fish, they are known to reach up to 10 feet (3 meters) in length and perhaps even weighing in excess of 400 lb (180 kg). This species is also one of the rare air-breathing fish in existence which means it needs to come up to the surface to breathe.

Fossil records show that the piraricu has been living in the waters of the great Amazon River since the Jurassic period so this truly is a prehistoric creature. They are extremely wide and have a gray scaly body and a tapered head.

The arapaima can stay underwater for around 10 to 20 minutes but they choose to remain near the surface of the water generally. This is so they can hunt and emerge to breathe. On emergence they make a huge distinctive coughing noise.

Unlucky fellow nabbed by a giant otter

This species feasts mainly on fish but occasionally gets lucky and grabs a bird flying low over the water’s surface. Unfortunately, its need to remain so close to the water’s surface makes it highly vulnerable to human predators and the arapaima often finds itself harpooned. Tribes indigenous to the Amazon area are known to make jewelery out of its scales and consume its tongue as meat. People also have been known to enjoy fish steaks from the arapaima but in Brazil at least commercial fishing is banned.

These men captured a nicely colored specimen

Its reproductive cycle is governed by the Amazon’s floods. In the low water months (February to April) both the male and female constructs nests and the female then lays the eggs. The offspring hatch at the perfect time when water levels begin to rise and flood conditions allow them to flourish. Another interesting fact is how the male arapaimas incubates tens of thousands of eggs in their mouths. They become very aggressive and protective and when necessary move the eggs to safety. When the offspring are hatched their parents can communicate with them via the secretion of a special hormone from their heads. This allows the adult fish to protect their young from danger and predators.

Arapaima can be kept in aquariums but they are so large in size it would be difficult to maintain an adequate habitat for them.