Arapaima

If some reports of its size are correct, the arapaima is the largest living species of freshwater fish in the world. Yet, despite its massive size, it is an amazingly gentle, caring parent.

This Amazon heavyweight is reported to grow to 16 feet in length. However, most reliable reports indicate that it grows to about two thirds of this size. Even so, the arapaima, or pirarucu, is a real giant. In areas away from those occupied by humans, the arapaima is believed to

live in quite large numbers. Amazonian rivers and their main tributaries are also huge, and it is very difficult to reach some areas where arapaima are known, or believed, to occur. It is therefore certain that there are more arapaima than scientists once thought, but they do not know how many. Of one thing they are sure—in some areas close to human settlements, hunting has virtually wiped out this magnificent air-breathing fish.

Breeding with a Difference

One of the most interesting features of the arapaima is its breeding method. Unlike most large species, which shed huge numbers of eggs into the water, the arapaima produces relatively few eggs. Egg laying and fertilization takes place in a shallow pit dug in the riverbed. Once the eggs have been fertilized, one of the parents—believed to be the male—picks them up in its mouth, where they develop and hatch in safety. The parent that protects the young in this way also produces pimplelike growths on its snout. It is thought that these growths produce nourishing substances on which the babies feed when they hatch out.