Bagrus bajad (Forsskål, 1775)
Bayad
Bagrus bajad
photo by Hippocampus-Bildarchiv

 Family:  Bagridae (Bagrid catfishes)
 Max. size:  112 cm FL (male/unsexed); max.weight: 13 kg; max. reported age: 8 years
 Environment:  demersal; depth range - 60 m, potamodromous
 Distribution:  Africa: Nile River, Lake Chad, Niger and Senegal River, Lakes Mobutu (Lake Albert) and Turkana. Reported from Sanaga River basin (Ref. 27691).
 Diagnosis:  Dorsal spines (total): 1-1; Dorsal soft rays (total): 8-12; Anal spines: 0-0; Anal soft rays: 13-15; Vertebrae: 48-53. Diagnosis: body rather elongate, 5-6 times longer than deep (Ref. 7324, 57125); occipital process 4-6 times longer than broad (Ref. 57125). 9-11 branched dorsal-fin rays (Ref. 57125), the first prolonged into short filaments (Ref. 13851, 31256, 57125). Longest filament comprised 3-4 times in standard length (Ref. 7324, 57125). Predorsal length 2.4-2.6 times in standard length; head width 1.7-2.2 times in head length; width of premaxillary tooth plate 2.5-2.8 times in head length; caudal-fin lobes often prolonged into short filaments; upper caudal-fin lobe comprised 2-3 times in standard length (Ref. 57125). Description: head much depressed, smooth above (Ref. 43434), but often ridged (Ref. 4903), and roundly pointed when viewed from above (Ref. 28714). Supralateral eyes with a free orbital margin (Ref. 367, Ref. 11410). Posterior and anterior nostrils remote from each other, the posterior being provided with a barbel (Ref. 11410). Premaxillary tooth plate 6-7 times as long as broad, a little shorter than the vomerine tooth plate (Ref. 43434). Nasal barbel 0.3-0.6 times the head length (Ref. 367). Maxillary barbel reaching ventral or anal fin (Ref. 43434). External mandibular barbel 0.7-1.1 times head length; internal mandibular barbel 1.7-2.1 times head length (Ref. 367). Occipital processus in contact with the first interneural (Ref. 42499, Ref. 2756). Dorsal fin with smooth spine (Ref. 367). Last ray of dorsal fin behind inner ray of ventral fin (Ref. 4912). Adipose fin height 2.5 times in length of its base (Ref. 3036) and its length twice as long as rayed dorsal fin, narrowly separated one from another (Ref. 43434). Lobes of caudal fin often with short filaments (Ref. 7324, Ref. 13851). Pectoral spine as long as dorsal spine and with serrations at the inside (Ref. 2756, Ref. 367). No pectoral filaments (Ref. 3036, Ref. 2756). Pelvic fins inserted under 5th or 6th branched ray of dorsal fin (Ref. 3036, Ref. 13851). Lateral line system consists of a straight line of tubular elevations, from the scapulare to the middle of the caudal fin (Ref. 562). Coloration: life specimens yellow-greenish or blackish with white belly (Ref. 7324, 13851, 57125). Fins darker, sometimes reddish purple; juveniles with little black spots on the sides (Ref. 7324, 57125).
 Biology:  Found in lakes, swamps and rivers (Ref. 31256). Avoids salt water (Ref. 31439). Spends nearly the whole of the daylight hours in crevices of rocks and is therefor seldom seen (Ref. 51850). Lives and feeds on or near the bottom (Ref. 3034). Adults exclusively piscivorous (Ref. 31256). Preys on small fish, particularly Alestes spp. (Ref. 13851), or Chrysichthys auratus as in Lake Kainji (Ref. 3034); also feeds on insects, crustaceans, mollusks, vegetable matter (Ref. 28714). Efficiency of catching prey catfish is maximised by face to face attack, avoiding damage by dorsal and pectoral spines of the prey (Ref. 33614). There is some indication that the species comes to shallower water to breed (Ref. 43507). Spawning season extends from April to July (Ref. 51850). Parents build and guard the nest, which is like a flat disc with a central hole where the eggs are dropped (Ref. 51638). Size of the nest and the central hole depend on the fish size (Ref. 51638). Males become up to 7 years old, females 8 years (Ref. 51644). Mean sizes and weight of males are less than those of females from the same age (Ref. 51644, Ref. 51645). An important food fish. Flesh is good eating and of economic importance (Ref. 36900), commonly sold as food (Ref. 43521). Reputed to reach 100,000 g.
 IUCN Red List Status:   (Ref. 96402)
 Threat to humans:  harmless
 Country info:   
 

 Entered by: Luna, Susan M. - 18.05.92
 Modified by: Reyes, Rodolfo B. - 18.07.13
 Checked by: Luna, Susan M. - 05.08.94

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