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Table 1.1 List of reservoirs studied, including data on area and potential fish yields (after Crul, 1992)

NameCountryAreaPot. yield (t/y)
Kafue Flats/GorgeZambia4 340.0
18 476
KossouCôte d'lvoire1 600.0
7 378
Jebel AuliaSudan1 500.0
6 952
BuyoCôte d'lvoire900.0
4 345
LagdoCameroon700.0
3 448
MteraTanzania610.0
3 038
ManantaliMali600.0
2 992
MbakaouCameroon500.0
2 530
MwadingushaZaire446.0
2 278
SelingueMali409.0
2 103
ItezhitezhiZambia360.0
1 870
MagaCameroon360.0
1 870
BamendjingCameroon300.0
1 582

Table 2.1 Summary of limnological data for some Cameroonian rivers

Source:
river;
location;
De Kimpe (1980a)
Benue
Lagdo
SOGREAH, 1983
Benue
Lagdo
Logone
Bongor
Sanega
Nachtigal
pH
7.2
7.5
7.7
7.1
Conductivity
   mho/cm
80.0
μS/cm   
122   
50   
30   
HCO3 mg/l
55   
55   
45.7
16.3
Cl mg/l
3   
3.0
-   
0.7
NO2
0   
-   
-   
-   
NO3
4.9
-   
-   
-      
PO4
0   
-   
-   
-   
Ca
9.0
9.0
5.6
3.1
Mg
2.0
2.0
2.1
1.0
Na
3.9
3.9
3.5
1.8
K
3.0
3.0
1.8
1.6
NH4
0   
-   
-   
-   
SiO2
20   
20   
-   
14.4
SO4
-   
-   
0   
0.8
Fe
-   
-   
-   
0.78
TDS
-   
-   
-   
39.0

TDS = total dissolved solids

Table 2.2 Fishermen, boats and gear by ethnic group around Lake Lagdo, February 1990 (after Van der Knaap et al., 1991a)

 12345678910111213141516171819
Subtotal for Djoukoun/Agatou26353666025201911257700280.0782.0206002015464
Subtotal for Fishermen from Far North80183974149121002862130901.51575.570015060613
Subtotal for Haussa/Kabawa27123846119197002931712134.0623.5488070939411
Subtotal for Local fishermen597284600510040121190315.0893.015305191464
Subtotal for Fishermen from Mali28127051100260009.035.0029900
TOTAL1960190919929857381318392361321639.53909.01361871140930272

1. Masterfishermen
2. Assistants
3. Outboards
4. 5 HP
5. 8 HP
6. 15–16 HP
7. 25 HP
8. 30 HP
9. 40 HP
10. Plywood canoes
11. Dugout canoes
12. On foot
13. Gourd
14. 200 mesh net
15. 400 mesh net
16. Hooks
17. Traps
18. Nile perch net
19. Castnet

Table 2.3 Annual fish production by fishing enterprise at Lake Lagdo (after Van der Knaap et al., 1991b)

YearProduction
(t)
Number of enterprisesAnnual production (t) by enterprise
1985/19867 6561 1936.42
1986/198713 4041 4869.02
1987/198812 8761 8007.15
198910 5001 6596.33
199012 2891 9606.27

Table 2.4 Annual fish production by unit area at Lake Lagdo (after Van der Knaap et al., 1991b)

YearProduction
(t)
Mean surface
(km2)
Production
(kg/ha)
1985/19867 656381201
1986/198713 404395339
1987/198812 876436295
198910 500600175
199012 289600205
199110 675600178

Table 2.5 Monthly average catch rates for gillnets of various mesh sizes (mm) (after Van der Knaap et al., 1991b)

Month40–99No.100–129No.130–223No.
January8.862112.974249.051
February5.95517.082410.101
March5.471710.576316.8911
April7.1278.9333-0
May7.62414.45357.151
June7.78732.30346.368
July8.55725.603524.036
August9.691319.894611.246
September4.831815.09295.5311
October8.3879.1932-0
November5.9018.084-0
December3.07115.1925-0

Table 2.6 Species composition for three categories of gillnets, based on mesh size

SpeciesMesh
> = 130
mm
%Mesh
100 < = x
< 130 mm
%Mesh
40 < = x
< 100 mm
%
SCHILBE MYSTUS0.010.040.010.030.211.57
LABEO SENEGALENSIS0.180.650.461.502.4117.97
SAROTHERODON GALILAEUS15.6656.3325.4482.812.5519.02
SAROTHERODON NILOTICUS0.361.291.595.180.231.72
BARUS BAYAD0.250.900.260.850.473.50
SYNODONTIS SPP0.020.070.180.590.745.52
CHRYSICHTHYS SPP0.150.540.160.523.8528.71
CLARIAS LAZERA0.040.140.020.070.020.15
TILAPIA ZILLI0.030.110.050.160.110.82
ALESTES NURSE0.040.14 0.000.443.28
AUCHENOGLANIS OCCIDENTALIS0.541.940.682.211.007.46
GYMNARCHUS NILOTICUS 0.00 0.00 0.00
ALESTES MACROLEPIDOTUS 0.000.010.030.584.33
HEPSETUS ODOE 0.00 0.000.010.07
CTENOPOMA SPP 0.00 0.000.030.22
HEMICHROMIS SPP 0.00 0.000.010.07
CITHARIUNS CITHARUS4.0014.391.234.000.181.34
HYDROCYNUS SPP5.9221.290.170.550.130.97
HETEROTIS NILOTICUS0.180.650.130.420.030.22
CHANA OBSCURA0.010.04 0.00 0.00
POLYPTERUS SPP 0.00 0.000.100.75
PROTOPTERUS ANNECTENS 0.00 0.00 0.00
MORMYRUS AND MORMYROPS SPP0.130.47 0.00 0.00
TETRAODON FAHAKA0.020.070.070.230.080.60
HETEROBRANCHUS BIDORSALIS 0.00 0.00 0.00
LABEO COUBIE0.010.040.020.070.010.07
HYPEROPISUS BEBE0.050.180.020.07 0.00
DISTICHODUS SPP0.080.290.010.03 0.00
CLAROTES SPP0.020.070.030.10 0.00
EUTROPIUS NILOTICUS 0.00 0.00 0.00
GNATHONEMUS SPP 0.000.020.070.040.30
EPIPLATYS SPP 0.00 0.00 0.00
TYLOCHROMIS JENTINKI 0.00 0.00 0.00
BARILIUS SPP 0.00 0.00 0.00
LATES NILOTICUS0.080.290.150.490.151.12
MALAPTERURUS ELECTRICUS0.020.070.010.030.020.15
ALESTES BARILIUS 0.00 0.000.010.07
TOTAL27.8010030.7210013.41100

Table 2.7 Frame survey results of Maga Reservoir, Cameroon (Dr Baba Malloum Ousman, pers. comm.)

YearFishermenCanoesNetsLonglinesTraps
1986/1987    8394351 1531 465-
1987/19881 1209121 4832 172-
1988/19891 4809461 62410 820300
1989/19901 4809561 62410 820300
1990/19911 8116941 4031 569 97
1991/19921 8116941 4041 569 97

Table 2.8 Fish production from Maga Reservoir (Dr Baba Malloum Ousman, pers. comm.)

YearTonnes
19842 603
19852 623
1986700
19871 229
19883 642
19893 585
19901 161
19911 241
19921 766

Table 2.9 Summary of figures on fishery potential of four reservoirs in Cameroon

ReservoirFishery potential t/year 1)Fishery potential t/year 2)
Bamendjing   5001 582
Mbakaou3 5002 530
Lagdo2 9003 448
Maga1 5001 870

1) Summarized from Vanden Bossche and Bernacsek (1990b) who compiled data from Balarin (1985), who in his turn modified data after SOGREAH, 1983 b; Laclavere and Loung, 1980; Aubray, 1976.
2) Summarized from Crul (1992).

Table 2.10 List of fish species caught in the Maga Reservoir and Logone River, including their vernacular names (after De Kimpe, 1980b)

 MASSAMOUSGOUMFOUFOULDE
Heterotis niloticusHeraouhina Laréou
Hyperopisus bebeMouranaAvriSoudao
Mormyrus sp.BinendanadaDo'ni 
  Ankoï 
Gnathonemus sp.BinendanadaMoukoum say 
Petrocephalus sp.Moudina Soudao
Gymnarchus niloticusSinildaMounkouYaouni
TetraodonMamoukKorkotoBagoulidi
HydrocynusChekah'laGoéSagaie
  Yiehou 
Alestes dentexDjiod'haAniaKetchaperado
Alestes baremoze HackdiPelepelekou
Alestes macrolepidotus Gerken'kou 
Ichthyoborus BotchenchebekouYarendeou
Citharinus MadaraïFalia
  Abade 
DistichodusDakaouasnaTchenchebakoSiaké
  Bedjef 
Barbus sp.Koulay Souleina Dabalabala
Bidé   
Labeo sp.BlaraGirgilaBidé
BagrusLacturendiMalaoBlagi
AuchenoglanisPininaGougourouNakaset
ClariasNon'nanHoedeiMoubalao
SchilbeNerek'maKotoboSolet
  Bezné 
EutropiusNerek'maBeznéSolet
SynodontisGuémilaKokoyeKouroungou
Malapterurus electricus AmbourniniFeféoundé
Lates niloticusGoeklof'naMaldangAkaltao
Tilapia sp.SilaïdjaraïnaAsougouniFaraoré
PolypterusChallaYamBodiou
ProtopterusSoïdaMoukouloumBoyénaou
  Abd'haï 

Table 3.1 Summary of information on water level, surface and volume of Lake Kossou

 Year Level (m ASL)Surface (km2)Volume (km3)
minimummaximumminimummaximumminimummaximum
1971157.89183.45-485-3.
1972183.15186.154755903.7  5.
1973184.10187.935056804.156.
1974186.50190.446108255.6   8.
1975-192.87-863-9.
1987184.00188.005007003.9   6.

Table 3.2 Summary of physico-chemical parameters for Lake Kossou (after Bearez, 1988)

Water temperature: average 29°C, range 29–33°C
Transparency: range 130–280 cm
Conductivity (20°C): 100 μ S/cm
Alkalinity: 50 ppm CaCO
  
Dissolved oxygen: seldom over 5 mg/l
pH: range 7.5 – 8.0

Table 3.3 Development of the fishery at Lake Kossou for the period 1972–1975 (estimated from data collected by Bazigos and Begin) (after Entz, 1984)

Mean annual number of full-time fishermen

YearLake surfaceFishermen trained by AVBIvorians attractedTotal IvoriansForeign fishermenAVB canoesGillnetsProduction (t/y)
197148083(?)(?)(?)41600(?)
1972600226500726645185(10 000)5 640
19736808125411 35366986316 8004 905
19748101 5487682 3166541 18420 9027 355
19756251 6239072 53001 30515 728-
(June)        

(AVB: ‘Autorité pour l'aménagement de la vallée du Bandama’ or Bandama Valley Management Authority)

Table 3.4 Number of fishing gear sets, boats, fishermen and fishing camps by administrative region (after Bearez, 1988)

Administrative region Number of fishing gearNumber of canoes Number of fishermenNumber of fishing camps
SeinesGillnetsLonglinesTrapsCastnetsForeignIvorian
YAMOUSSOUKRO
TIEBISSOU
106
  40
605
460
130
135
1 450
1 450
54
  8
260
240
220
200
35
20
20
25
TOTAL1461 0652652 900625004205545

Table 3.5 Annual fish yield estimates at Lake Kossou (after Bearez, 1988)

YearProduction (in tonnes)Yield (kg/ha/year)
19725 430106
19734 69582
19747 35589
19755 10567
19767 335102
19779 315147
19787 518129
19878 000133

Table 4.1 Summary of baseline limnological data from Bafing River (after Anne et al., in press).

 April 1977October 1978
Electric conductivity μ S/cm44.148.5
pH6.68.2
   
O2 (ppm)6.08.4
iron (ppm)0.030.06
   
ammonium (ppm)0.090.13
silicates (ppm)8.79.2
phosphate (ppm)<0.01<0.01

Table 5.1 Summary of physico-chemical data for Jebel Aulia Reservoir (various sources as quoted by Vanden Bossche and Bernacsek, 1991 and Khalid, 1990

 Vanden Bossche et al., 1991 Khalid, 1990 
 Source Source
Surface temperature21.0 – 29.5°CWelcomme, 197216–31°CAsma, 1985
Transparency  45–85 cmPonedelko et al, 1964
   12.5–52 cmAsma, 1985
Dissolved solids180 mg/l - dam endWelcomme, 1972  
 120 mg/l - river end   
Dissolved oxygen  5.0–6.5 mg/lPonedelko et al, 1964
   4.1–10.8 mg/lAsma, 1985
pH9.2 - dam endWelcomme, 19728.35–8.40Ponedelko et al, 1964
 7.5 - river endBrook and Rzoska, 19547.4–8.6Asma, 1985
 8.0–8.3 at centreTalling, 1957  
Conductivity  160 – 330 μS/cmAsma, 1985
Ionic composition mg/l Talling, 1957  
 Ca8 – 11   
 CaCO365 – 70   
 Cl3 – 7   
 SO41   
 SiO26.11   
 Fe0.1 – 0.5   
 NO3-N0.02 – 0.06 0.05 mg/lPonedelko et al, 1964
 NH3-N0.04 – 0.06   
 PO4-P0.04 – 0.10   

Table 5.2 List of commercial species caught in Jebel Aulia Reservoir, their contribution to the total production, and their local names (Asma, 1985)

Scientific name% of catchVernacular name
Hydrocynus forskalii5.6Kas
Chrysichthys auratus5.2Abu Reyala
Labeo horiae5.0Tutkum
Alestes baremose4.8Kawara
Eutropius niloticus4.6Schilbaya Arabi
Oreochromis niloticus4.6Bulti
Hydrocynus lineatus4.4Kas
Synodontis schall4.4Gargour

Table 6.1 List of fish species caught in the Great Ruaha River and its tributaries

Mormyrus longirostris
Gnathonemus livingstoni
Gnathonemus macrolepidotus
Gnathonemus sp.
Petrocephalus catostoma
Hippopatamyrus discorhynchus
Mormyrid sp. 1
Mormyrid sp. 2
Alestes affinis
Hydrocynus vittatus
Distichodus petersii
Distichodus rufigiensis
Barbus macrolepis
Barbus zanzibaricus
Barbus jacksonii
Barbus innocens
Barbus paludinosus
Barbus kerstenii
Barbus neumayeri
Barilius loveridgei
Labeo spp.
Bagrus orientalis
Synodontis maculipinna
Synodontis matthesi
Schilbe mystus
Eutropius mobiusii
Pareutropius longifilis
Clarias mossambicus
Tilapia urolepis
Haplochromis gr. ‘bloyeti’

Table 6.2 Summary of available data on number of fishermen, boats and gear as well as on fish production (t) for the Mtera Reservoir (after Lyimo, pers. comm.)

NumberYear 1986198719901991
Fishermen1 2381 4931 8151 716
Boats1 0441 2041 4721 478
Gillnets (")10 82510 8253 6573 657
 2175175  
 2.5873873238238
 34 2374 237360360
 3.52 4022 4022 9462 946
 42 8172 817307307
 4.5287287  
 534345858
 5.5    
 6  2424
 6.5  1010
 7  2121
Hooks29 17229 17210 32110 321
Traps1821825252
     
Production3 2543 3613 7615 025

Table 7.1 Summary of available physio-chemical data for the Mwadingusha Reservoir

Surface temperature:25–26°C in rainy season
Conductivity:K20 128–309 μS/cm
pH:7.1–8.2; 7.5–8.4 (Konare, 1984)
Oxygen:15.0 mg/l, Jan.; 2.0, April;
 21.0, July (Konare, 1984)
Ionic composition:mg/l
Na3.07–6.0
K0.78–1.56
Ca11.04–49.07
Cl0.71–2.49
SO40.19–5.0
SiO214.06–21.06
NO3-N3.01–11.02
PO4-N9.0–18.0

Table 7.2 Summary of existing annual catch figures for the Mwadingusha Reservoir

YearTotal catch (t)No. of fishermenNo. of boats
1953314--
19542 354--
19557 991--
1956674--
19571 359--
19584 223--
1959–60---
19616 115--
1962–77---
19781 500--
1979–81---
19824 350--
19833 106*1 4101 583**

* 1 606 t marketed fish + 1 500 t fishermen consumption
** Konare, 1984


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