PART II - SYNTHESES OF INFORMATION ON SELECTED AFRICAN RESERVOIRS (continued)

PARTIE II - SYNTHESES DE L'INFORMATION SUR CERTAINS RESERVOIRS AFRICAINS (continuer)

KAINJI (NIGERIA) (continued)

Table 14. Standing stock (kg) and density of fish species and families captured in 21 retenone samples in Kainji Lake between 1975 and 1976 (From Ita, 1981b)

Family/Species		Mean Ichthyomass/ha	Mean Density/ha	Total Number	Mean Wt. (g)
1	CICHLIDAE
	Sarotherodon galilaeus	42.39	1 470.89	7 030	30.5
	S. niloticus	35.22	324.29	2 783	101.3
	Tilapia zillii	24.96	559.22	3 419	46.0
	Chromidotilapia guentheri	1.71	148.58	779	12.2
	Hemicromis bimaculatus	0.23	9.47	49	28.8
	H. bimaculatus	0.17	28.54	118	5.8
	Tilapia dageti	0.01	0.34	1	15.0
		104.69	2 541.33
2	BAGRIDAE
	Bagrus bayad	15.56	71.00	228	205.6
	Chrysichthys auratus	9.51	993.18	3 778	9.8
	Auchenoglanis occidentalis	5.76	144.16	898	36.7
	Clarotes laticeps	1.85	45.45	279	45.0
	Auchenoglanis biscutatus	1.48	7.12	30	198.4
	Bagrus docmac	0.99	5.52	26	136.7
	Chrysichthys nigrodigitatus	0.73	38.89	152	19.1
	C. furcatus	0.03	0.12	1	225.0
		35.91	1 305.44
3	CITHARINIDAE AND DISTICHODONTIDAE
	Citharinus citharus	33.13	184.37	829	173.7
	Distichodus rostratus	1.97	37.78	146	54.4
	Citharinus distichodoides	0.37	7.50	28	45.1
	Paradistichodus dimidiatus	0.23	102.67	434	2.2
		35.70	332.32
4	CHARACIDAE
	Alestes macrolepidotus	6.19	201.26	992	27.3
	A. dentex	5.44	144.76	640	34.3
	A. baremose	5.35	371.01	1 298	14.2
	A. leuciscus	2.49	431.48	1 293	6.0
	A. nurse	2.15	111.26	532	19.4
	Hydrocynus forskahlii	2.01	7.89	32	226.2
	Alestes brevis	0.97	39.65	135	27.9
	Hydrocynus vittatus	0.02	0.25	1	72.0
		24.62	1 307.56
5	CYPRINIDAE
	Labeo senegalensis	8.96	279.91	1 179	35.5
	L. coubie	2.99	32.60	147	78.0
	L. pseudocoubie	0.50	8.69	48	63.1
	Barbus spp.	0.27	212.52	1 281	1.4
	Labeo parvus	0.25	6.46	28	42.0
	Barbus macrops	0.12	64.61	154	1.8
	Barilius niloticus	0.01	0.29	1	40.0
		13.10	605.08
6	MOCHOKIDAE
	Synodontis batensoda	2.59	37.11	120	59.3
	S. gambiensis	1.30	33.70	119	39.1
	S. nigrita	0.92	19.91	93	44.3
	S. membranaceus	0.42	18.69	69	20.4
	S. ocellifer	0.27	9.95	21	30.2
	S. eupterus	0.20	10.01	34	19.8
	S. budgetti	0.18	3.89	11	43.6
	S. filamentosus	0.15	26.47	205	5.1
	S. gobroni	0.03	0.31	1	100.0
	S. vermiculatus	0.01	0.37	2	35.0
	S. sorex	0.001	1.30	3	0.7
		6.07	161.71
7	MALAPTERURIDAE
	Malapterurus eletricus	5.92	42.13	229	131.9
8	CLARIIDAE
	Clarias anguillaris	3.49	15.98	123	213.3
	C. lazera	1.87	15.45	115	134.2
		5.36	31.43
9	MORMYRIDAE
	Mormyrus rume	1.67	12.66	37	136.1
	Marcusenius senegalensis	0.59	19.38	71	31.3
	Mormyrops deliciosus	0.42	11.35	51	44.9
	Marcusenius kainji	0.11	6.36	31	16.6
	Hippopotamyrus psittacus	0.11	14.88	60	8.0
	Petrocephalus bovei	0.11	17.80	53	5.8
	Hyperopisus bebe	0.08	1.88	7	45.7
	Marcusenius cyprinoides	0.08	2.15	7	35.7
	Mormyrus hasselquisti	0.05	0.92	3	53.3
	Petrocephalus bane	0.03	10.70	36	2.9
	Hyppopotamyrus pictus	0.02	1.33	4	13.0
	Pollimyrus isidori	0.01	0.61	14	1.9
		3.28	100.02
10	CENTROPOMIDAE
	Lates niloticus	2.78	116.68	73	96.8
	SCHILBEIDAE
	Schilbe mystus	0.24	18.60	90	11.7
	Eutropius niloticus	0.14	8.66	34	18.6
	Physailia pellucida	0.02	13.50	46	1.5
		0.40	40.76
12.	OTHERS
	Polypterus senegalus	0.72	19.65	69	45.2
	Channa obscurus	0.42	4.20	17	85.7
	Pellonula afzeliusi	0.36	412.12	1 952	0.9
	Mastacembelus leonnbergi	0.07	5.91	45	7.8
	Hepsetus odoe	0.05	0.22	1	215.0
	Phago loricatus	0.03	0.77	6	41.7
	Protopterus annectens	0.03	1.37	4	21.3
	Ctenopoma kingsleyae	0.01	0.87	4	14.5
	Tetrodon fahaka	0.01	0.11	1	110.0
	Garra waterloti	0.01	0.70	4	7.0
		1.71	445.92
	GRAND TOTAL	239.54	7 030.38

Table 15. Mean and percentage ichthyomass (in kg) of fish families sampled in Kainji Lake arranged in order of decreasing ichthyomass; compared with percentage weight of gill-net catches along the shore in 1976 (From Ita, 1981b)

Family	Rotenone		Gill-net*
Family	Ichthyomass	%	% Wt. at Shore
Cichlidae	104.69	43.71	25.5
Bagridae	35.91	14.99	12.6
Citharinidae and Distichodontidae	35.70	14.90	8.9
Characidae	24.62	10.28	14.8
Cyprinidae	13.10	5.47	14.8
Mochokidae	6.07	2.53	8.9
Malapteruridae	5.92	2.47	-
Clariidae	5.36	2.24	0.2
Mormyridae	3.28	1.37	4.5
Centropomidae	2.78	1.16	7.7
Schilbeidae	0.40	0.17	0.6
Other species	1.71	0.71	1.5
T O T A L	239.54	100.00

* Progress Report April 1976 – March 1977, Kainji Lake Research Institute

Table 16. Percentage composition by number of fish families in the shore, surface and bottom samples for 1976 (adjusted according to effort) (From Ita, 1978)

Family	Shore	Surface	Bottom	Total fish
Characidae	26.1	70.0	3.9	357
Mochokidae	37.4	31.3	31.3	313
Cichlidae	71.5	27.4	1.1	186
Cyprinidae	63.3	12.2	24.5	196
Citharinidae	44.4	43.8	11.7	162
Bagridae	40.7	11.1	48.2	162
Schilbeidae	10.0	47.7	42.3	130
Mormyridae	46.5	15.1	38.4	86
Centropomidae	53.7	29.3	17.1	41
Others	50.0	33.3	16.7	24
Total fish	41.8	36.6	21.6	1 657

Table 17. Mean ichthyomass (kg) and density per hectare of fish species estimated from 21 rotenone samples in Kainji Lake. (Numbering reflects order of importance)

Fish Species	No.	Mean Ichthyomass/ha	Mean Density/ha	No.
Sarotherodon galilaeus	1	42.39	1 470.89	1
S. niloticus	2	35.22	324.29	7
Citharinus citharus	3	33.13	184.37	11
Tilapia zillii	4	24.96	559.22	3
Bagrus bayad	5	15.56	71.00	18
Chrysichthys auratus	6	9.51	993.18	2
Labeo senegalensis	7	8.96	279.91	8
Alestes macrolepidotus	8	6.19	201.26	10
Malapterurus electricus	9	5.92	42.13	21
Auchenoglanis occidentalis	10	5.76	144.16	14
Alestes dentex	11	5.44	144.76	13
A. baremose	12	5.35	371.01	6
Clarias anguillaris	13	3.49	15.98	36
Labeo coubie	14	2.99	32.60	27
Lates niloticus	15	2.78	116.68	15
Synodontis batensoda	16	2.59	37.11	25
Alestes leuciscus	17	2.49	431.48	4
A. nurse	18	2.15	111.26	16
Hydrocynus forskahlii	19	2.01	7.89	49
Distichodus rostratus	20	1.97	37.78	24
Clarias lazera	21	1.87	15.45	37
Clarotes laticeps	22	1.85	45.45	20
Chromidotilapia guentheri	23	1.71	148.58	12
Mormyrus rume	24	1.67	12.66	40
Auchenoglanis biscutatus	25	1.48	7.12	50
Synodontis gambiensis	26	1.30	33.70	26
Bagrus docmac	27	0.99	5.52	54
Alestes brevis	28	0.97	39.65	22
Synodontis nigrita	29	0.92	19.91	30
Chrysichthys nigrodigitatus	30	0.73	38.89	23
Polypterus senegalus	31	0.72	19.65	31
Marcusenius senegalensis	32	0.59	19.38	32
Labeo pseudocoubie	33	0.50	8.69	46
Channa obscurus	34	0.42	4.20	55
Synodontis membranaceus	35	0.42	18.69	33
Mormyrops deliciosus	36	0.42	11.35	41
Citharinus districhodoides	37	0.37	7.50	48
Pellonula afzeliusi	38	0.36	412.12	5
Synodontis ocellifer	39	0.27	9.95	44
Barbus spp.	40	0.27	212.52	9
Labeo parvus	41	0.25	6.46	51
Schilbe mystus	42	0.24	18.60	34
Hemichromis fasciatus	43	0.23	9.47	45
Paradistichodus dimidiatus	44	0.23	102.67	17
Synodontis eupterus	45	0.20	10.01	43
S. budgetti	46	0.18	3.89	56
Hemichromis bimaculatus	47	0.17	28.54	28
Synodontis filamentosus	48	0.15	26.47	29
Eutropius niloticus	49	0.14	8.66	47
Barbus macrops	50	0.12	64.61	19
Marcusenius kainjii	51	0.11	6.36	52
Hippopotamyrus psittacus	52	0.11	14.88	38
Petrocephalus bovei	53	0.11	17.80	35
Hyperopisus bebe	54	0.08	1.88	58
Marcusenius cyprinoides	55	0.08	2.15	57
Mastacembelus leonnbergii	56	0.07	5.91	53
Hepsetus odoe	57	0.05	0.22	72
Mormyrus hasselquisti	58	0.05	0.92	62
Phago loricatus	59	0.03	0.77	64
Protopterus annectens	60	0.03	1.37	59
Chrysichthys furcatus	61	0.03	0.12	73
Petrocephalus bane	62	0.03	10.70	42
Synodontis gobroni	63	0.03	0.31	69
Hippopotamyrus pictus	64	0.02	1.33	60
Hydrocynus vittatus	65	0.02	0.25	71
Physailia pellucida	66	0.02	13.50	39
Ctenopoma kingsleyae	67	0.01	0.87	63
Synodontis vermiculatus	68	0.01	0.37	67
Tetraodon fahaka	69	0.01	0.11	74
Barilius niloticus	70	0.01	0.29	70
Tilapia dageti	71	0.01	0.34	68
Garra waterloti	72	0.01	0.70	65
Pollimyrus isidori	73	0.01	0.61	66
Synodontis sorex	74	0.001	1.30	61
Total		239.54

Table 18. Food and feeding habitats of fishes in some tropical man-made lakes (from Ita and Morcos, 1981)

	Food types	Kainji*	Kariba
Primary Consumers	Bottom deposits, filamentous algae and higher plants	Alestes spp. h(5), Labeo spp. h(4), Serotherodon spp. h(2), Tilapia spp. h(2), Citharinus spp. h(2), Distichodus h(3), spp. Barbus occidentalis, Synodontis batensoda, S. gobroni, S. resupinatus, S. budgetti, S. melanopterus, S. eupterus, S. nigrita, S. schall, Auchenoglanis occidentalis, Micralestes acutidens, Sierrathrissa leonensis, Pellonula afzelius, Garra waterloti, Mastacembelus loennbergi	Tilapia mortimeri, Tilapia rendalli, Labeo altivelis, Distichodus scienga, Labeo congoro, Tilapia andersonii, Distichodus mossambicus, Alestez lateralis, Barbus fasciolatus, Barbus unitaeniatus, Micralestes acutidens, Labeo cylindricus, Barbus lineomaculatus, B. prechii, Labeo lunatus, Barbus paludinosus
Secondary Consumers	(mainly insectivores), insect larvae, molluscs and crustaceans	Synodontis clarias, S. courtetti, S. vermiculatus, S. violaceus, S. filamentosus, S. sorex, S. ocellifer, S. gambiensis, Marcusenius spp. h(4), Mormyrus spp. h(3), Mormyrops deliciosus, Petrocephalus spp. h(3), Hyperopisus bebe, Hippopotamyrus spp. h(2), Polymyrus spp. h(2), Hemichromis bimaculatus, Chrysichthys spp. h(3), Auchenoglanis biscutatus, barilius senegalensis, Chromidotilapia guntheri, Tetraodon fahaka, Heterotis niloticus, Campylonormyrus tamandus	Sargochromis giardi, Haplochromis carlottae, Haplochromis darlingi, Hemihaplochromis philander
Tertiary Consumers	(Biscivors) fish	Hydrocynus spp. h(3), Bagrus spp., Clarotes laticeps, Schilbe spp. h(2) Lates niloticus, Gymnarchus niloticus, Hemichromis fasciatus, Polypterus spp. h(3), Malapterurus electricus, Hetrobranchus bidorsalis, Hepsetus odoe, Arius gigas, Channa obscurus, Phago loricatus, Eutropius niloticus, Clarias sp.	Hydrocynus vittatus, Clarias gariepinus Sargochromis codringtoni, Heterobranchus longifilis, Mormyrops deliciosus, Mormyrus longirostris, Serranochromis robustus, Serranochromis macrocephalus, Eutropius depressirostris, Malapterurus Electricus, Schilbe mystus
	Food types	Nasser	Volta**
Primary Consumers	Bottom deposits, filamentous algae and higher plants	Alestes spp. h(3), Citharinus Citharus, Labeo spp. h(4), Synodontis schall, Auchenoglanis occidentalis, Sarotherodon spp. h(2)	Alestes spp. h(5), Synodontis schall, S. nigrita, S. membranaceus, Labeo spp. h(4), Tilapia spp. h(2), Distichodus spp. h(2), Citharinus spp. h(2), Pellonula afzeliusi, Auchenoglanis occidentalis, Sarotherodon spp. h(2), Barbus spp.
Secondary Consumers	(mainly insectivores), insect larvae, molluscs and crustaceans	Barilius niloticus Auchenoglanis biscutatus, Chrysichthys auratus, Chrysichthys ruppelli, Mormyrus spp. h(2), Tetraodon fahaka	Physalia pellucida, Ctenopoma Kingsleyae, Siluranodon auritus, Marcusenius brachyistius, Chrysichthys spp. h(3), Tetraodon spp. h(2), Synodontis gambiensis, Hemichromis bimaculatus, Hyperopisus bebe, Mormyrus spp. h(3), Synodontis sorex, S. ocellifer, Gnathonemus spp. h(5), Polypterus senegalus, Petrocephalus spp. h(4), Mormyrops deliciosus, Pelmatochromis guntheri, Heterotis niloticus
Tertiary Consumers	(Biscivors) fish	Mormyrops anguilloides, Hydrocynus forskalii, Bagrus spp. h(2), Eutropius niloticus, Schilbe spp. h(2), Clarias lazera, Heterobranchus bidorsalis, H. longifilis, Malapterurus electricus, Lates niloticus	Clarias spp. h(3), Schilbe mystus, Hydrocynus spp. h(4), Hemichromis faciatus, Lates niloticus, Polypterus spp. h(2), Hepsetus odoe, Bagrus spp. h(2), Ophicephalus obscurus, Heterobranchus spp. h(2), Eutropius spp. h(2), Clarotes laticeps, Malapterurus electricus, Gymnarchus niloticus, Protopterus spp. h(2)

* Extracted from Ita and Otubusin (Unpubl.)

** The information was modified from Evans and Vanderpuye (1973)