Table 8. Percentage composition of fish by number, in gillnet catches for the year 1976 (estimated from a total of 137 gillnet fleets) and the relative distribution in the shore, surface and bottom samples (from Ita, 1978)
Family/Species | Number | % | Distribuion (%) | |||
Shore | Surface | Bottom | ||||
CHARACIDAE | ||||||
Hydrocynus forskalii (Cuvier) | 89 | 5.91 | 18.9 | 69.5 | 11.6 | |
Alestes dentex (Cuvier & Valenciennes) | 83 | 5.50 | 14.3 | 84.5 | 1.2 | |
Alestes baremose (Joannis) | 80 | 5.31 | 19.5 | 76.8 | 3.7 | |
Alestes macrolepidotus (Cuvier & Valenciennes) | 52 | 3.45 | 43.4 | 56.6 | - | |
Alestes nurse (Ruppell) | 42 | 2.78 | 56.8 | - | - | |
Alestes brevis (Boulenger) | 1 | 0.07 | 100.0 | - | - | |
Hydrocynus brevis (Günther) | 1 | 0.07 | - | 100.0 | - | |
Total | 348 | 23.09 | ||||
MOCHOKIDAE | ||||||
Synodontis batensoda (Ruppell) | 67 | 4.44 | 45.7 | 50.0 | 4.3 | |
Synodontis gambiensis (Günther) | 60 | 3.98 | 12.3 | 7.4 | 80.2 | |
Synodontis membranaceus (Geoffroy St. Hilaire) | 51 | 3.38 | 26.8 | 51.8 | 21.4 | |
Synodontis nigrita (Cuvier & Valenciennes) | 30 | 1.99 | 41.2 | 32.4 | 26.5 | |
Synodontis filamentosus (Boulenger) | 30 | 1.99 | 100.0 | - | - | |
Synodontis ocellifer (Boulenger) | 29 | 1.92 | 40.6 | 40.6 | 18.8 | |
Synodontis eupterus (Boulenger) | 3 | 0.20 | 33.3 | - | 66.7 | |
Synodontis schall (Bloch Schneider) | 2 | 0.13 | - | 100.0 | - | |
Synodontis budgetti (Boulenger) | 1 | 0.07 | - | 100.0 | - | |
Synodontis sorex (Günther) | 1 | 0.07 | 100.0 | - | - | |
Synodontis violaceus (Pellegrin) | 1 | 0.07 | - | 100.0 | - | |
Synodontis omias (Günther) | 1 | 0.07 | - | 100.0 | - | |
Total | 276 | 18.31 | ||||
CICHLIDAE | ||||||
Sarotherodon galilaeus (Linnaeus) | 128 | 8.50 | 74.6 | 24.6 | 0.8 | |
Sarotherodon niloticus (Linnaeus) | 41 | 2.72 | 62.8 | 37.2 | - | |
Tilapia zilii Gervais | 8 | 0.53 | 77.8 | 22.2 | - | |
Total | 177 | 11.75 | ||||
CYPRINIDAE | ||||||
Labeo senegalensis Cuvier & Valenciennes | 139 | 9.22 | 63.9 | 10.9 | 25.2 | |
Labeo coubie Ruppell | 30 | 2.00 | 51.4 | 17.1 | 31.4 | |
Labeo pseudocoubie Blache & Milton | 5 | 0.33 | 66.7 | 33.3 | - | |
Total | 174 | 11.55 | ||||
CITHARINIDAE/DISTICHODONTIDAE | ||||||
Distichodus rostratus Günther | 91 | 6.04 | 52.1 | 41.7 | 6.3 | |
Citharinus citharus (Geoffory St. Hilaire) | 49 | 3.25 | 36.4 | 40.0 | 23.6 | |
Citharinus distichodoides Pellegrin | 12 | 0.80 | 30.8 | 69.2 | - | |
Total | 152 | 10.09 | ||||
BAGRIDAE | ||||||
Chrysicthys auratus (Pfaff) | 50 | 3.32 | 46.6 | 20.6 | 32.8 | |
Chrysichthys nigrodigitatus | 35 | 2.32 | 2.0 | 2.0 | 96.0 | |
Bagrus bayad Pfaff | 26 | 1.72 | 66.7 | 10.0 | 23.3 | |
Clarotes laticeps Ruppell | 12 | 0.80 | 92.3 | - | 7.7 | |
Auchenoglanis occidentalis (Cuvier & Valencienne) | 6 | 0.40 | 83.3 | 16.7 | - | |
Bagrus docmac (Forskal) | 4 | 0.20 | 40.0 | - | 60.0 | |
Auchenoglanis biscutatus Geoffry & St. Hilaire | 1 | 0.07 | - | 100.0 | - | |
Total | 134 | 8.89 | ||||
SCHILBEIDAE | ||||||
Eutropius niloticus (Ruppell) | 68 | 4.51 | 9.0 | 48.7 | 42.3 | |
Schilbe mystus (Linnaeus) | 31 | 2.06 | 10.5 | 39.5 | 50.0 | |
Physalia pellucida Boulenger | 13 | 0.86 | 14.3 | 64.3 | 21.4 | |
Total | 112 | 7.43 | ||||
MORMYRIDAE | ||||||
Marcusensius senegalensis (Steindachner) | 29 | 1.92 | 44.4 | 5.6 | 50.0 | |
Hyperopisus bebe (Gunther) | 14 | 0.93 | 11.8 | 35.3 | 52.9 | |
Hyppopotamyrus pictus (Marcusen) | 12 | 0.80 | 64.3 | 7.1 | 28.6 | |
Mormyrops deliciosus (Leach) | 7 | 0.46 | 77.8 | 11.1 | 11.1 | |
Mormyrus rume Cuvier & Valenciennes | 7 | 0.46 | 71.4 | 14.3 | 14.3 | |
Mormyrus macrophthalmus Gunther | 3 | 0.20 | - | 50.0 | 50.0 | |
Marcusenius kainji sp.nov. | 1 | 0.07 | 100.0 | - | - | |
Marcusenius cyprinoides (Linnaeus) | 1 | 0.07 | 100.0 | |||
Total | 74 | 4.91 | ||||
CENTROPOMIDAE | ||||||
Lates niloticus (Linnaeus) | 38 | 2.52 | 54.8 | 28.6 | 16.6 | |
OTHERS | ||||||
Ctenopoma kingsleyae Gunther | 7 | 0.46 | 28.6 | 71.4 | - | |
Gymnarchus niloticus Cuvier | 4 | 0.26 | 80.0 | 20.0 | - | |
Ghana obscurus (Gunther) | 2 | 0.13 | 100.0 | - | - | |
Arius gigas Boulenger | 2 | 0.13 | - | - | 100.0 | |
Heterotis niloticus (Cuvier) | 1 | 0.07 | 100.0 | - | - | |
Barilius niloticus (Joannis) | 1 | 0.07 | 100.0 | - | - | |
Hemichromis fasciatus Peters | 1 | 0.07 | 100.0 | - | - | |
Hepsetus odoe (Bloch) | 1 | 0.07 | 100.0 | - | - | |
Clarias anguillaris (Linnaeus) | 1 | 0.07 | 100.0 | - | - | |
Clarotes macrocephalus Daget | 1 | 0.07 | - | - | 100.0 | |
Barbus occidentalis Boulenger | 1 | 0.07 | 100.0 | - | - | |
Total | 22 | 1.47 | ||||
Grand total | 1 507 |
Table 9. Relative abundance of fish caught in the cofferdammed lake (4.8.1966 to 21.8.1966) (from Motwani and Kanwai, 1970)
Fish species | Numbers caught | Total weight (kg) | ||||
MORMYRIDAE | ||||||
Hyperopisus occidentalis | 166 | 48.81 | ||||
Mormyrus rume | 91 | 29.69 | ||||
M. macrophthalmus | 87 | 16.96 | ||||
M. hasselquisti | 2 | 0.50 | ||||
Mormyrops deliciosus | 84 | 36.45 | ||||
M. oudoti | 37 | 17.84 | ||||
M. engystoma | 1 | 0.45 | ||||
Petrocephalus bane ansorgei | 12 | 0.27 | ||||
P. psittacus | 29 | 0.76 | ||||
P. harringtoni | 1 | 0.13 | ||||
P. isidori | 1 | 0.04 | ||||
Gnathonemus tamandua | 366 | 37.91 | ||||
G. abadii | 140 | 12.74 | ||||
G. senegalensis | 108 | 10.50 | ||||
G. deboensis | 43 | 4.19 | ||||
G. pictus | 26 | 1.52 | ||||
G. petersii | 2 | 0.08 | ||||
G. niger | 1 | 0.10 | ||||
G. cyprinoides | 1 | 0.02 | ||||
Total: | 1 198 | 218.96 | ||||
Percentage of Total Catch: | 20.70 | 19.54 | ||||
CHARACIDAE | ||||||
Hydrocynus forskali | 27 | 8.90 | ||||
H. lineatus | 1 | 1.90 | ||||
Alestes baremose | 942 | 64.75 | ||||
A. dentex | 505 | 35.70 | ||||
A. leuciscus | 498 | 4.16 | ||||
A. macrolepidotus | 95 | 18.04 | ||||
A. nurse | 34 | 2.69 | ||||
A. imberi | 1 | 0.09 | ||||
Total: | 2 103 | 136.23 | ||||
Percentage of Total catch: | 36.27 | 12.16 | ||||
CITHARINIDAE | ||||||
Distichodus rostratus | 63 | 115.44 | ||||
D. engycephalus | 3 | 2.68 | ||||
Citharinus citharus | 276 | 91.13 | ||||
C. distichoides | 9 | 1.17 | ||||
C. latus | 3 | 1.62 | ||||
Total: | 354 | 212.04 | ||||
Percentage of Total Catch: | 6.10 | 18.92 | ||||
CYPRINIDAE | ||||||
Labeo coubie | 125 | 38.61 | ||||
L. senegalensis | 53 | 8.50 | ||||
L. pseudocoubie | 5 | 1.08 | ||||
Barbus occidentalis | 1 | 0.03 | ||||
Barbus sp. | 7 | 0.01 | ||||
Barilius senegalensis | 1 | 0.04 | ||||
Total: | 192 | 48.27 | ||||
Percentage of Total Catch: | 3.30 | 4.30 | ||||
SCHILBEIDAE | ||||||
Schilbe mystus | 350 | 33.95 | ||||
Eutropius niloticus | 98 | 6.60 | ||||
Physailia pellucida | 15 | 0.10 | ||||
Total: | 463 | 40.65 | ||||
Percentage of Total Catch: | 8.00 | 3.63 | ||||
BAGRIDAE | ||||||
Bagrus docmac | 148 | 121.24 | ||||
B. bayad | 39 | 36.12 | ||||
Chrysichthys auratus | 106 | 8.41 | ||||
C. nigrodigitatus | 89 | 8.56 | ||||
C. furcatus | 9 | 11.03 | ||||
Clarotes laticeps | 25 | 13.47 | ||||
C. macrocephalus | 6 | 5.38 | ||||
Total: | 422 | 204.21 | ||||
Percentage of Total Catch: | 7.25 | 18.22 | ||||
MOCHOCIDAE | ||||||
Synodontis gobroni | 392 | 54.75 | ||||
S. gambiensis | 152 | 12.49 | ||||
S. budgetti | 125 | 61.49 | ||||
S. membranaceus | 116 | 45.38 | ||||
S. violaceous | 58 | 5.02 | ||||
S. courteti | 53 | 13.03 | ||||
S. vermiculatus | 53 | 7.04 | ||||
S. sorex | 27 | 2.08 | ||||
S. ocellifer | 19 | 1.15 | ||||
S. resupinatus | 19 | 2.90 | ||||
S. batensoda | 11 | 0.88 | ||||
S. robbianus | 10 | 0.33 | ||||
S. melanopterus | 9 | 0.19 | ||||
S. clarias | 7 | 0.89 | ||||
S. nigrita | 5 | 0.46 | ||||
S. schall | 3 | 0.30 | ||||
S. omias | 3 | 1.08 | ||||
S. filamentosus | 2 | 0.04 | ||||
Total: | 1 044 | 209.50 | ||||
Percentage of Total Catch: | 18.00 | 18.68 |
Table 10. Summary of fish catches in River Niger (1965 and 1966) and Kainji Lake (1969) (from Imevbore and Okpo, 1975)
Families | River 1965 | River 1966 | Lake 1969 | ||
% No. | % No. | % Wt. | % No. | % Wt. | |
characidae | |||||
Alestes longipinnis | - | - | - | 0.02 | 0.001 |
A. dentex | 2.44 | 8.71 | 3.34 | 0.02 | 0.001 |
A. baremose | 16.25 | 6.05 | 0.42 | 0.03 | |
A. macrolepidotus | 0.32 | 1.64 | 1.67 | 0.12 | 0.08 |
A. nurse | 1.12 | 0.59 | 0.25 | 0.38 | 0.03 |
A. imebri | 0.017 | 0.008 | - | - | |
A. leuciscus | 8.59 | 0.39 | - | - | |
Hepsetus odoe | 0.37 | - | - | ||
Hydrocynus forskalii | 0.47 | 0.83 | 0.07 | 0.20 | |
H. vittatus (lineatus) | 0.32 | 0.017 | 0.18 | 0.70 | 1.83 |
total % | 4.57 | 36.28 | 12.72 | 1.73 | 2.17 |
mormyridae | |||||
Mormyrops deliciosus | 0.22 | 1.45 | 3.41 | - | - |
M. macrophthalmus | 1.97 | 1.50 | 1.59 | - | - |
M. rume | 0.22 | 1.57 | 2.78 | 0.24 | 0.31 |
M. hasselquisti | 0.05 | 0.03 | 0.05 | 0.10 | 0.02 |
Gnathonemus senegalensis | 0.13 | 1.86 | 0.98 | - | - |
G. pictus | 0.15 | 0.45 | 0.14 | - | - |
G. tamandua | 1.90 | 6.32 | 3.54 | - | - |
Hyperopisus bebe | - | 2.86 | 4.56 | 0.02 | 0.02 |
Petrocephalus bane | 0.70 | 0.21 | 0.03 | 0.02 | 0.001 |
Mormyrops oudoti | 0.70 | 0.63 | 1.67 | 0.02 | 0.001 |
M. engystoma | 0.017 | 0.04 | - | - | |
Petrocephalus psittacus | 0.50 | 0.07 | - | - | |
P. harringtoni | 0.017 | 0.01 | - | - | |
P.isoderii | 0.017 | 0.004 | - | - | |
Gnathonemus abadii | 11.13 | 2.42 | 1.19 | 0.02 | 0.006 |
G. debonensis | 0.74 | 0.39 | - | - | |
G. petersii | - | 0.03 | 0.007 | ||
G. niger | - | 0.017 | 0.009 | ||
G. cyprinoides | - | 0.017 | 0.002 | 0.16 | 0.03 |
total % | 17.17 | 20.66 | 20.47 | 0.58 | .39 |
cyprinidae | |||||
Labeo senegalensis | 1.95 | 0.91 | 0.79 | 0.35 | 0.49 |
L. coubie | 0.45 | 2.16 | 3.61 | 3.43 | 4.60 |
L. pseudocoubie | - | 0.09 | 0.10 | 0.54 | 0.84 |
Other Labeo spp. | 1.00 | ||||
Barbus occidentalis | 0.03 | 0.077 | 0.003 | 0.02 | 0.03 |
Barbus sp. | - | 0.12 | 0.001 | - | - |
Barilius senegalensis | - | 0.017 | 0.004 | - | - |
total % | 3.43 | 3.37 | 4.51 | 4.34 | 5.96 |
cichlidae | |||||
Tilapia nilotica | 2.17 | - | - | 0.26 | 0.15 |
T.galilaea | 0.65 | - | - | 1.53 | 1.14 |
T. zilli | 0.92 | - | - | - | - |
T. melanopleura | - | - | - | 0.03 | 0.002 |
T. monodi | - | - | - | 0.10 | 0.01 |
Hemichromis fasciatus | 0.05 | - | - | 0.05 | 0.01 |
Pelmatochromis guentheri | - | - | - | - | - |
total % | 3.79 | 1.97 | 1.31 | ||
citharinidae | |||||
Distichodus rostratus | 1.55 | 1.09 | 10.79 | 0.12 | 0.24 |
D. engycephalus | 0.20 | 0.05 | 0.25 | - | - |
D. brevipinnis | 1.27 | 0.03 | 0.004 | ||
Citharinus citharus | 16.71 | 4.76 | 8.52 | 69.56 | 67.76 |
C. latus | 3.99 | 0.05 | 0.15 | 2.04 | 4.31 |
C. distichodoides | 0.50 | 0.16 | 0.11 | 2.33 | 1.84 |
Citharidium ansorgei | 0.15 | 0.03 | 0.004 | ||
total % | 24.37 | 6.11 | 19.82 | 74.11 | 74.16 |
centropomidae | |||||
Lates niloticus | 0.27 | - | - | 2.16 | 2.96 |
total % | 0.27 | - | - | 2.16 | 2.96 |
schilbeidae | |||||
Schilbe mystus | 2.49 | 6.04 | 3.17 | 0.26 | 0.08 |
Eutropius niloticus | 2.97 | 1.69 | 0.62 | 0.02 | 0.01 |
Siluranodon auritis | - | 0.02 | 0.001 | ||
Physalia pellucida | - | 0.26 | 0.009 | 0.09 | 0.001 |
Other spp. | 0.03 | - | - | - | - |
total % | 5.49 | 7.99 | 3.80 | 0.39 | 0.09 |
bagridae | |||||
Chrysicthys nigrodigitatus | 0.52 | 1.54 | 0.80 | 0.05 | 0.01 |
Chrysicthys auratus | - | 1.83 | 0.79 | 0.64 | 0.13 |
C. furcatus | - | 0.16 | 0.13 | - | - |
Bagrus bayad | 0.27 | 0.67 | 3.38 | 0.12 | 0.27 |
B. filamentosus | - | 0.03 | 0.05 | ||
B. docmac | 0.05 | 2.55 | 11.33 | - | - |
Auchenoglanis occidentalis | 0.25 | 0.91 | 0.79 | ||
A. biscutatus | - | 0.05 | 0.06 | ||
Clarotes laticeps | 0.67 | 0.43 | 1.26 | 0.10 | 0.01 |
Clarotes macrocephalus | - | 1.04 | 0.50 | - | - |
Other spp. | 0.89 | - | - | - | - |
total % | 2.65 | 8.22 | 18.19 | 1.90 | 1.32 |
mochokidae | |||||
Synodontis membranaceus | 0.96 | 2.00 | 4.24 | 7.91 | 6.49 |
Other spp. | 19.03 | ||||
Synodontis gobroni | 6.76 | 5.12 | 0.12 | 0.02 | |
S. gambiensis | 2.62 | 1.17 | 0.16 | 0.03 | |
S. budgetti | 2.16 | 5.75 | 0.09 | 0.04 | |
S. violaceous | 1.00 | 0.50 | - | - | |
S. courteti | 0.91 | 1.22 | 0.03 | 0.004 | |
S. vermiculatus | 0.91 | 0.66 | - | - | |
S. sorex | 0.47 | 0.19 | 0.56 | 0.20 | |
S. ocellifer | 0.33 | 0.11 | 0.51 | 0.03 | |
S. resupinatus | 0.33 | 0.27 | - | - | |
S. batensoda | 0.19 | 0.08 | 0.42 | 0.22 | |
S. robbianus | 0.17 | 0.03 | - | - | |
S. melanopterus | 0.16 | 0.02 | 0.02 | 0.003 | |
S. clarias | 0.12 | 0.08 | 0.42 | 0.09 | |
S. nigrita | 0.09 | 0.04 | 0.07 | 0.01 | |
S. schall | 0.05 | 0.03 | 0.16 | 0.02 | |
S. eupterus | 0.38 | 0.03 | |||
S. omias | 0.05 | 0.1 | - | - | |
S. filamentosus | 0.03 | 0.004 | - | - | |
total % | 19.99 | 18.35 | 19.61 | 10.85 | 7.19 |