Common names: African catfish, barbel, sharptooth catfish (Eng.); skerptand-baber (Afr.); bavuri (Xitsonga) bavhuri (Tshivhenda).
Derivation of scientific name: Clarias: Greek, chlaros = lively; gariepinus: named after its type locality, the Gariep River.
The sharptooth catfish (Clarias gariepinus), has a long, flattened body covered in smooth skin without any scales, which helps it move easily through water and along the bottom of rivers/dams etc. Its head is broad and flat, ending in a strong, bony shield that helps it dig into the substrate and protects it in murky water.
Description/How to recognise a sharptooth catfish
The sharptooth catfish has a large mouth set slightly underneath its head, surrounded by four pairs of whisker-like barbels. These barbels help it sense its surroundings and find food, even in very low light. Its skin colour varies, often showing a mix of dark brown, olive and grey on top, fading to a pale, creamy underside. This countershading helps it blend in with its environment, whether in still or flowing water.
Getting around
The catfish has a long dorsal fin that runs along most of the length of its back, and a similarly long anal fin that meets it near the tail. This fin arrangement helps the catfish swim smoothly and efficiently. Its pectoral fins have hard spines that can be raised for defence, which is important for both its behaviour and classification.
Communication
The sharptooth catfish has a complex range of mechanosensory and subaqueous acoustic communication methods. By causing the pectoral fin spines to rub against their basal girdles, it creates stridulatory oscillations that generate low-frequency vibratory pulses that can travel a considerable distance through the water. These signals are significantly increased during intraspecific aggression, territorial demarcation and pre-spawning groups, but significantly decreased during reproductive isolation in submerged vegetative habitats.
Distribution
The native range of C. gariepinus spans almost all of the African continent, except for Lower and Upper Guinea, Maghreb. The sharptooth catfish is the most widely distributed fish in Africa, largely due to its ability to tolerate a wide variety of habitats, as well as all over the world due to its introduction as an aquaculture species. In South Africa, the sharptooth catfish’s natural distribution ranges from the west (north of the Orange River system) to the east (north of the Umtamvuna River, between KwaZulu Natal and the Eastern Cape).
Habitat
Clarias gariepinus is generally regarded as a freshwater species though it may be found in many different habitats, including the higher reaches of estuaries. It prefers floodplains, sluggish flowing rivers, lakes and dams. It can withstand low dissolved oxygen and highly turbid waters and is often the last or only fish species seen in remnants of drying rivers.
Food
Clarias gariepinus is recognised as an omnivorous species, exhibiting characteristics of both scavenging and predation. It has a highly diverse diet that includes fruits and seeds, various aquatic invertebrates and small vertebrates, small mammals and even plankton. As individuals increase in size, they exhibit a distinct change in their diet, favouring fish.
Inactive foods, which it identifies using its sensory barbels before grasping them with its set of tiny teeth and swallowing, are usually favoured. However, sharptooth catfish are also skilled predators, capable of hunting in groups, where they can drive schools of small fish towards underwater plants before consuming them.
Sex and life cycle
Sex
Before spawning, schools of sharptooth catfish move upstream or towards still water bodies. Courtship, spawning and egg laying happen at night, usually after periods of rain. The eggs stick to underwater plants; this may be aquatic or even terrestrial plants that have recently been immersed under seasonal water level increase. Typically, 24 and 36 hours after spawning, the eggs will hatch. Catfish parents do not nurture their young, and so the newly hatched fish are left to forage for themselves. On average, a 2 kg C. gariepinus fish, has a fecundity of roughly 45 000 eggs.
Family life
Sharptooth catfish are mostly solitary fish but can occasionally form loose aggregations in conditions that favour this, such as when feeding, or in small habitats, such e.g., drying pools and aquaculture tanks. They are very adaptable and can live in many types of freshwater environments, including rivers and lakes, swamps and man-made ponds.
They are mostly nocturnal and come out at night to feed on insects, smaller fish, crustaceans and plant matter, then retreat to hiding places during the day under debris, in burrows, or among submerged structures. They form temporary pairs during the breeding season, but do not have long-term social bonds; most of the time they are independent and territorial and can survive in harsh or low-oxygen environments because they are able to breathe air.
THE BIG PICTURE
The sharptooth catfish is a pivotal trophic position within aquatic ecosystems, functioning as both a consumer and an ecological regulator. As an omnivore and benthic feeder, it has a significant impact on trophic dynamics by modifying populations of invertebrates, detritus-associated creatures and smaller piscine species, so helping to maintain ecological balance and nutrient flow. Its scavenging abilities promote sediment bioturbation and organic matter remineralisation, hence improving nutrient cycling and primary productivity in lentic and lotic systems.
In contrast, it serves as a key prey resource for piscivorous birds, reptiles and mammals, hence bridging the aquatic and terrestrial food chains. Its facultative air-breathing capabilities allows it to dwell and maintain marginal or eutrophic aquatic environments with fluctuating oxygen levels, hence supporting biodiversity and ecological resilience within these systems.
Friends and foes
Sharptooth catfish occupy an intermediary yet assertive position within aquatic trophic hierarchies, engaging in both competitive and antagonistic interactions. They contend with other benthic omnivores – such as Tilapia rendalli (redbreast tilapia) and Oreochromis mossambicus (Mozambique tilapia) – for alimentary resources, while juveniles are vulnerable to predation by herons (Ardea spp.), cormorants (Phalacrocorax spp.) and piscivorous fishes like African tigerfish (Hydrocynus vittatus).
Mature individuals, however, face few natural adversaries aside from crocodiles (Crocodylus niloticus) and humans. In non-native systems, their ecological plasticity and predatory aptitude render them formidable competitors, capable of displacing indigenous species and altering community structures.
Smart strategies
gariepinus has two key evolutionary adaptations: an accessory air-breathing organ (comprising suprabranchial chambers and labyrinthine structures) that enables aerial respiration when aquatic oxygen is low, accounting for c. 90% of its total diffusing capacity for oxygen; and in turbid water, its elongated barbels operate as tactile mechanosensory appendages, allowing prey identification and navigation independent of vision – giving access to areas with minimal competition and low predation risk.
Poorer world without me
Without catfish, the aquatic environment would lose a crucial trophic regulator from its natural lentic and lotic habitats. This big benthic and demersal predator suppresses the growth of prey populations and prevents unchecked trophic cascades by consuming a wide variety of invertebrates, small vertebrates and detrital matter.
Without it, prey assemblages such as aquatic arthropods and small fishes would become exponential, resulting in increased biomass of basal consumers that could overexploit primary producers and disrupt nutrient cycles. At the same time, human reliance on chemical biocontrol (like pesticides) and mechanical intervention in riparian agriculture or aquaculture would increase, raising production costs, making ecosystems more vulnerable, and undermining sustainable biodiversity management.
People and I
The catfish motif can be seen in gold-weight imagery among the Akan (Ghana) in certain African cultural matrices. Its ability to endure in murky or oxygen deprived water is regarded figuratively as perseverance in the face of hardship and as a symbol of ingrained ancestral resilience.
Conservation status and what the future holds
The most recent IUCN assessment of the African Catfish Clarias gariepinus and is listed as Least Concern.
Relatives
The sharptooth catfish is a member of the genus Clarias, a diverse group of air-breathing catfishes in the family Clariidae and thus belongs to a broad taxonomic lineage of aquatic predators distinguished by specialised respiratory adaptations and elongated dorsal and anal fin morphologies.
Its nearest congeners on the African continent include other Clarias taxa that diverged to occupy distinct ecological niches; though exact species-level ‘closest relative’ at a continental scale may unclear, it is worth noting that the genus itself encompasses some sixty-odd recognised species worldwide, with a particularly dense radiation in Africa.
Official common name: Sharptooth catfish
Scientific name and classification:
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Family: Clariidae
Genus: Clarias
Species: C. gariepinus (Burchell, 1822)
References and further reading
- Animal Diversity Web. No date. Clarias gariepinus: Classification and general biology. University of Michigan Museum of Zoology. Retrieved from: https://animaldiversity.org/accounts/Clarias_gariepinus/
- Boyle, K.S., Colleye, O. & Parmentier, E. 2014. Sound production to electric discharge: sonic muscle, swimbladder and other signalling specialisations in catfishes (Siluriformes). BioMed Central Research Notes, 7: 320. https://doi.org/10.1186/1756-0500-7-320
- Bruton, M.N. 1979. The biology of Clarias gariepinus (Pisces: Clariidae) in Lake Sibaya, South Africa, with emphasis on aspects of the reproductive biology. Transactions of the Zoological Society of London, 35(1): 1–45.
- Clarias gariepinus summary page FishBase. Available at: https://www.fishbase.se/summary/Clarias_gariepinus.html (Accessed: 05 October 2025).
- Konings, A., Freyhof, J., FishBase team RMCA & Geelhand, D. 2019. Clarias gariepinus (amended version of 2018 assessment). The IUCN Red List of Threatened Species 2019: e.T166023A155051767. https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T166023A155051767.en. Accessed on 23 Spetember 2025.
- Jubb, R.A. 1967. Freshwater fishes of southern Africa. Cape Town, South Africa: A.A. Balkema.
- Safriel, O. & Bruton, M.N. 1984. A cooperative aquaculture research programme for South Africa. CSIR Report No. 89. Pretoria: CSIR.
- Skelton, P. 2001. A complete guide to the freshwater fishes of southern Africa. Struik Publishers, Cape Town.
- Teugels, G.G. 1986. A systematic revision of the African catfishes of the genus Clarias (Pisces: Clariidae). Annales du Musée Royal de l’Afrique Centrale, 247: 1–199.
- Van der Waal, B.C.W. 1998. Survival strategies of sharptooth catfish Clarias gariepinus in desiccating pans in the northern Kruger National Park. Koedoe – African Protected Area Conservation and Science, 41: 131–138
- Willoughby, N.G. & Tweddle, D. 1978. The ecology of the catfish Clarias gariepinus and Clarias ngamensis in the Shire Valley, Malawi. Journal of Zoology (London), 186: 507–534.
Author: Mantshadi Mdhlalose
E-mail: M.mdhlalose@sanbi.org.za