There is a peculiar species of sea-fish that keeps its eggs in its mouth. It is the catfish found in the Atlantic Ocean off the east coast of America. The most surprising fact about it is that instead of the female, the male takes on the responsibility of looking after the future family. After the eggs are laid and fertilized, the male quickly puts them into his mouth. They completely fill its mouth and prevent it from eating. It carries them around for a month. During this period it is unable to take its food, and lives off the food reserves built up before the spawning. Moreover, his motherly role does not end even after the hatching of eggs. For two more weeks, the youngsters swim into his mouth to hide when any danger threatens them.
There are seven kinds of fishes which are called catfish and are found in eastern and central North America. Some species, like the flathead catfish and blue catfish, can even weigh more than 45 kg. The catfishes live near the bottom of slow-moving rivers and lakes. They have four pairs of barbels around their mouth. These barbels look like the whiskers of a cat and hence they are called catfishes. The barbels are quite sensitive and help the catfish feel its way around and find food.
The electric catfish is one variety which uses electrical discharges to stun and capture other fishes. Its electric organs lie just under the skin and cover its body and part of the tail. A large catfish may even produce a current of 350 volts.
Another kind of catfish called Wels catfish grows to huge sizes in muddy-bottomed lakes in central Europe. Some specimens grow up to 9 feet in length and some others compete with Arapaima which is claimed to be the largest fresh water fish in the world.