Common name: Bichir, ornate bichir, Senegal bichir, rope fish
Species: Polypterus sp.
Bichirs are a very primitive species of fish, perhaps even the most primitive of the Actinopterygii, or rayed fishes. These snake-like fish reach from about 1-4 feet in length depending on the species, and are found in river wetlands of central Africa and Zaire.
Bichirs are very effective nocturnal predators, eating most anything that will fit into its elongated mouth. In a home aquarium, species of this fish will readily eat animals twice its size. This fish can be a fierce tank mate, however, it is not territorial, and will not bother a fish it can not eat. In fact, due to its modified fins and slow speed, care must be taken that the bichir is not harassed by more aggressive fish.
The bichirs are a very unique species, as anyone who has seen one will attest. Their front ventral fins look like a pair of legs with paddles attached. These strange fins are used to support the fish as he sits on the bottom of the river. The fins are also used during the spring wet season, when bichirs move into the more dense swampland along the rivers. They are known to use their "legs" to travel over areas of dryer land in search of mates or prey, getting oxygen from the two lunglike organs that these fish have.
The organs, a modified swim bladder, serve two purposes. The first is that they allow the fish to breath out of water, or at the surface of oxygen poor water. The other use for these organs is for flotation. Bichirs are slow moving bottom fish. In order to move through the water efficiently, they must gulp air for buoyancy , so that they can "walk" along the vegetation at the top.
At night, bichirs move to deeper water in search of large prey. Their slow speed in no way diminishes their ability to catch and eat HUGE quantities of other fish. The ability to sneak up on sleeping fish is their greatest asset.
In an aquarium, these are wonderful and interesting fish to keep if their needs can be met. The Senegal bichir and the ornate bichir are the two most common species seen in the aquarium trade. The ornate bichir, reaching about 3 feet in captivity, is one of the largest of this family and requires a very large tank with heavy filtration. The tank should be a minimum of 50 or 75 gallons and should be relatively shallow (1-2 ft. deep). They require daily feedings of beef heart (my bichir's favorite), raw fish, some plant matter, large insects, or earthworms (another favorite). Due to their thick keriton scales, these fish should also be fed shrimp on a regular basis. Although the ornate bichir is a very hearty fish, a deficiency in the diet can lead to thin scales. This may cause fungal or bacterial infections that can kill the fish. The Senegal bichir, a smaller species, reaches about 1.5 feet in length. The needs of this fish are similar to those of the ornate bichir, but the tank size may be a little smaller. Senegals still need a diverse meaty diet to stay healthy.