Environment: milieu / climate zone / depth range / distribution range
Freshwater; brackish; pelagic; potamodromous (Ref. 51243). Tropical; 22°C - 28°C (Ref. 12468)
Africa: present throughout intertropical Africa (Ref. 2880, 80290, 81279). Absence from the Gambia basin is noteworthy (Ref. 81279). Present in the Nile system (Ref. 28714, 58460) up to Lake Albert (Ref. 4903) and in Lake Turkana system (Ref. 28663). Widely distributed in the Congo River basin (Ref. 5331, 42019, 42510, 45434).
Length at first maturity / Size / Weight / Age
Maturity: Lm 18.5, range 33 - ? cm
Max length : 53.0 cm SL male/unsexed; (Ref. 2880); max. published weight: 2.0 kg (Ref. 3799)
soft rays: 13 - 19. Diagnosis: fronto-parietal fontanel absent in adults, sometimes pore-like in juveniles; snout long, comprimised 3x in head length; dorsal fin origin distinctly behind pelvic fin insertion; adults large-sized; no sexual dimorphism affecting anal fin shape; 21-31 lateral line scales; 4.5 scales between lateral line and dorsal fin; 10-16 anal fin branched rays; 14-22 gill rakers on lower limb of first gill arch; 8-14 teeth in outer premaxillary row (Ref. 2880, 80290, 81279). Head length/snout length 2.6-2.9; 10-12 predorsal scales (Ref. 80290). Body depth more than 3x SL in adults (Ref. 2880, 81279).
More common in rivers than lakes; feeds on insects, crustaceans, fish, vegetation and debris (Ref. 28714). Considering the distribution of different forms (according to collection determinations), it should be noted that a B. macrolepidotus 'form' is found only in northern regions, while a B. schoutedi 'form' is found only in southern regions. However, between these two forms there appears to be mixing and intermediacy of forms. We consider that there are several populations which have evolved in a geographical gradient to produce different morphotypes of a single species (Ref. 80290).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Paugy, D. and S.A. Schaefer, 2007. Alestidae. p. 347-411. In M.L.J. Stiassny, G.G. Teugels and C.D. Hopkins (eds.) Poissons d'eaux douces et saumâtres de basse Guinée, ouest de l'Afrique centrale/The fresh and brackish water fishes of Lower Guinea, west-central Africa. Vol. 1. Coll. Faune et Flore tropicales 42. Istitut de recherche pour le développement, Paris, France, Muséum nationale d'histoire naturelle, Paris, France and Musée royale de l'Afrique centrale, Tervuren, Belgique. 800 p. (Ref. 80290)
IUCN Red List Status (Ref. 126983)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01047 (0.00799 - 0.01373), b=2.98 (2.93 - 3.03), in cm total length, based on LWR estimates for this species (Ref. 93245
Trophic level (Ref. 69278
): 2.8 ±0.35 se; based on food items.
Generation time: 2.4 ( na - na) years. Estimated as median ln(3)/K based on 1 growth studies.
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Fishing Vulnerability (Ref. 59153
): Low to moderate vulnerability (31 of 100).