West African Bichir (Polypterus retropinnis)
| West African Bichir Polypterus retropinnis | |
|---|---|
 | |
| Name | West African Bichir |
| Name Lat. | Polypterus retropinnis |
| Family | Bichirs |
| Family lat. | Polypteridae |
| Order | Bichirs |
| Order lat. | Polypteriformes |
| Origin | Africa |
| Habitat | Tributaries, ponds |
| Diet | Carnivore |
| pH | 6.0-7.5 |
| Behavior | Predatory |
| Keeping | Individual, pair |
| Care Level | Difficult |
| Reproduction | Egg scatterer |
| Breeding | None reported |
| Life Span | 8-10 years |
| Protection | No |
| Metric Units | |
| Size | 30-40 cm |
| Temperature | 22-26 °C |
| Hardness | 8-18 °dH |
| Aquarium | 300 l |
| US Units | |
| Size | 12"-16" |
| Temperature | 72-79 °F |
| Hardness | 142-320 ppm |
| Aquarium | 80 gal |
Distribution and habitat
The West African ragged pike is widespread in western Africa, from the Democratic Republic of the Congo to Nigeria and Liberia. There they live in small rivers, streams, swamps and flooded areas with sandy or gravel bottoms.
Maintenance
The aquarium should have a dense border planting, with many hiding and retreat possibilities (roots, stones, caves). A soft substrate, subdued light (floating plant cover) and slightly acidic water is ideal. Due to their way of life they need only little swimming space and a shallow water depth, 30 cm is sufficient.
No ammonia, ammonium and nitrite should be detectable, the nitrate value should not exceed 100 mg/l. To ensure the water quality and the oxygen content, a filter adapted to the aquarium size and a heater are required, as well as lighting for the species-appropriate day-night rhythm of the animals.
Diet
The food supply consists of live food, such as tubifex, black mosquito larvae, shrimps, mussels, small fish, earthworms, mealworm lava and crayfish, which is also accepted in frozen form, supplemented with commercially available frozen special food mixtures. After habituation, high-quality protein-rich dry food (pellets) is sometimes also accepted
Only as much should be fed as is eaten within a few minutes. A regular and varied diet promotes health and prevents deficiency symptoms
Behaviour and compatibility
They are hardly aggressive within the species and should be kept in pairs. Keeping several animals is only possible in a much larger and richly structured tank. Towards other fishes they behave peacefully and can be socialized well with larger, calm fishes or other Polypterus species. Fish that are too small are considered food
Basically, only compatible fish species with similar demands on water condition and water temperature should be socialized.
Sex dimorphism
Males have a larger and thicker anal fin, which also serves as a mating organ.
Reproduction and breeding
There are no known confirmed reports of successful breeding in the aquarium. It is assumed that reproduction occurs as in other Polypterus. The eggs are taken over by the male for insemination during courtship and scattered over the plant thicket. After about 4 days, the fry hatch and swim free after another 3 days. The parents are spawn predators
The fry must be fed several times a day with special rearing food (artemia euplii, microworms). It is recommended to raise the fry individually, otherwise they will eat each other. In community tanks breeding is hardly possible, because the spawn is easy prey.
Important
They are crepuscular predators. Their swim bladder is divided into two parts, with the larger right part serving as an additional respiratory organ. This allows them to survive for some time out of the water in humid environments. They have to go to the water surface at intervals to breathe atmospheric air, as their gill breathing is not sufficient. If they are prevented from doing so, they suffocate
Care should be taken to provide good aquarium cover (spring protection), as there is a risk of escape, especially during the nocturnal periods of activity. They may lean on their ventrals to rest. The well-being of the fish should be checked regularly. Temperature should be checked daily, pH, hardness and nitrate levels at least fortnightly. Regular partial water changes are recommended, even if the contaminant level has not yet reached the upper limit. Sudden changes in water quality should be avoided. Newly introduced fish must be accustomed slowly to the water in the aquarium.
Further literature can be found in your pet store.
References
Text: petdata; Image: Franz Lowak
Source: BMELV (1998): Tierschutzgutachten - Haltung von Zierfischen (Süßwasser); BAENSCH & EVERS (2004): Aquarien Atlas Bd. 6, Mergus Verlag; ENGELMANN (2005): Zootierhaltung - Tiere in menschlicher Obhut: Fische, Verlag Harri Deutsch
- Gemäß § 21 Abs. 5 Tierschutzgesetz idgF