COUNTRY FILES (contd.)

CAMEROON

1. GEOGRAPHY AND CLIMATE (Welcomme, 1979)

Cameroon (with a surface area of 469 440 km²) is divided into four distinct topographical regions:

1. in the south there is a low coastal plain covered with equatorial rain forests;
2. in the centre there is a transitional plateau which rises to the north to the Adamaoua Mountains;
3. to the west there are mountain forests peaking in Mt. Cameroon (4 050 m);
4. to the north of Adamaoua range, rolling savanna slopes gradually down to the marshlands surrounding Lake Chad.

The climate is as varied as the topography but tends to grade from equatorial-humid in the south to Sahelian-arid in the north. In the south there is a prolonged and heavy rainy season which is at its most intense from June to September. The uplands have less rain and two peaks in April and October.

Cameroon is a primarily agricultural country with hardwood production in the forested areas. Demand for water for irrigation is limited. Several major dams have been installed for flood control, although they also generate electricity. There is a proposal to install a major area of irrigated agriculture on the Yaèrès floodplain down-stream of the proposed Logone River Dam.

2. HYDROGRAPHY (mainly after Balarin, 1985) (see Fig. 1)

Cameroon is characterized by an extremely dry north but very wet, high-altitude western regions. There are numerous perennial rivers in the south with extensive flood-plains.

The total water area amounts to about 2% of the country, nearly 40 000 million m³ and one million hectares, divided as follows (Aubray, 1976):

Table 1 gives data on the main waterbodies and their fishery potential.

2.1 Lakes

There are a number of natural lakes in Cameroon. The largest is Lake Chad, of which 800 km² (“Little Chad” phase) to 1 800 km² (“Normal Chad” phase) are Cameroon territory, or 8–40% of the lake area, depending on the floods (Welcomme, 1979). Other minor lakes (see Table 2), amounting to about 1 500 km² (Aubray, 1976), are scattered around the western region of the country.

2.2 Rivers, Floodplains and Swamps

Cameroon is drained from the Adamaoua Range along four major drainage basins: Atlantic, Zaire/Congo, Niger and Chad (Fig. 1, Table 1). A watershed exists along the South Cameroon Plateau separating coastal and Congo systems.

Within the plateau and coastal lowlands, the Atlantic drainage system is also divided into three minor basins: West, Sanaga and South. The Sanaga is the largest single river in Cameroon (over 920–975 km), with a 140 000 km² basin. Flows range from 473 m³/s (March) to 57 000 m³/s (October), with a mean of 2 072 m³/s. The river is characterized by a numer of rapids and reservoirs. The west Atlantic rivers converge and create the vast Cameroon Estuary. In the south are numerous very small rivers, among which is the Nyong, with an extensive marshland.

The Lake Chad Basin is the smallest river system in Cameroon, with the River Logone as the main element which overflows into a number of lakes and the Yaèrès swamp. Part of this system's waters can join the Benouè system via the Mayo/Kebi. Other rivers termed “Moya” imply seasonal flows characterized by rainfall.

Generally, flow patterns of all Cameroon rivers are typified by rainfall. Equatorial conditions in the south create no flood peaks per season (i.e., Lobe and Nyong). Further north, flows are continuous all year round, with only one peak flood (i.e., Sanaga and Wouri). In the extreme north Sahelian conditions typify one peak flood with dry periods for 6–8 months (i.e., Mayo Tsanga). The ratio of flow per basin area (expressed as l/s/km²) is therefore greatest in the south, declining toward the north.

All rivers are interrupted by rapids and waterfalls; they are shallow and obstructed by sand banks, hazards to navigation.

Water quality parameters of various rivers are given in Table 8.

Characterized by hydromorphic soils and typical vegetation, large areas are prone to inundation. The major floodplains (Fig. 1) are the Yaèrès, over 7 000 km² at peak flood, the upper reaches of the Nyong, and over 1 000 km² of mangrove swamps, mainly around the Wouri Estuary. Bell and Canterbery (1976), however, estimate that the total extent of mangrove is over 5 184 km².

2.3 Reservoirs

There are several impoundments in Cameroon:

• 4 in the Sanaga River system (Edea, Song-Loulou, Mbakaou and Bamendjing);
• Lagdo on the Garoua River (40 m-high dam; 7.7 km³ storage volume);
• Maga (10 m-high dam, 360 km² area);
• Bini (closed 1962; 3.0 km² area);
• Dang (closed 1963; 1.0 km² area);
• Mayo Oulou (80 km²);
• 7 reservoirs in the Mount Mandara area.

Two further large dams have been proposed: one on the Benue at Lagolo, and one on the Logone River.

Also listed (Table 2) are details of man-made reservoirs and those hydroelectric schemes proposed for construction. Two of the largest dams, Bamendjing and Mbakaou on the Sanaga River, have a marked seasonal fluctuation and the latter has also been known to dry up completely. Two of the most recent barrages, Maga and Lagdo, have recently been reviewed by De Kimpe (1980a,b; 1983).

2.4 Coastal Lagoons

Although there are extensive coastal mangrove forests/swamps (see section 2.2), there are no significant coastal lagoons.

Fig. 1. MAIN DRAINAGE BASINS AND HYDROLOGICAL STATIONS
(SOGREAH, 1983a mod. in Balarin, 1985)

Table 1. CAMEROON WATERBODIES AND THEIR FISHERY POTENTIAL
(Balarin, 1985)

Modified after: SOGREAH, 1983b; Laclavère and Loung, 1980; Aubray, 1976

Letters and Numbers before water-body names refer to Fig. 1.

Table 2. MORPHOLOGICAL DATA AND USES OF LAKES - CAMEROON
(Abstr. SOGREAH, 1983a; Min.Econ.Plan., 1981)
(Balarin, 1985)

^a c = commercial;
f = fishery;
i = irrigation;
p = power;
w = water supply

2.5 Aquaculture

There are 38 state Fish Culture Centres, but a large number of these are in a state of disrepair or abandonment. There are 6 000–7 000 village ponds in Cameroon (Satia, pers.comm.). SOGREAH (1982a) lists only 1 600 ponds as functional in 1982, but Satia (pers.comm.) considers this to be more in the order of 4 000, operated by 3 200 farmers, 1.3 ponds per farmer at a size of 250–300 m² each. This adds up to a total area of 100–120 ha with an average yield of 1.7 t/ha/yr. Grover et al., (1980), lists over 250–500 ha of ponds. Njock (1979), on the other hand, claims about 6 000 rural ponds, each of 250–400 m², operated by 4 500 farmers and capable of a mean production of 1 t/ha/yr. A total 150–240 t/yr, and about 2 million seeds, were considered as the total for 1980. Statistics therefore remain confused.

3. FISHERY PRODUCTION/POTENTIAL

3.1 Fish production and per caput supply

Table 3. FISH PRODUCTION AND PER CAPUT SUPPLY - Cameroon, 1970–1987

¹ Source: FAO
² Source: FAO Fisheries Department FISHDAB
Reliable catch data exist only for industrial fishery. Yields from inland water bodies known to be reduced as a result of Sahelian drought, but data on annual variations in catch are not available.
³ included in “Inland capture” if not specified.
⁴ - = data not available.
⁵ Vincke, 1989 (pers.comm.)
⁶ From 1980 to 1983, marine exports were as follows: 1980: 1 783 t; 1981: 1 434 t; 1982: 1 800 t; 1983: 2 002 t.

3.2 Inland catch range and potential yield

Table 4. INLAND CATCH RANGE AND POTENTIAL YIELD

(Sources: see text)
¹ before the Sahelian drought: “Normal Chad” phase
² during the Sahelian drought: “Little Chad” phase.
³ Balarin, 1985 (see Table 1)

Total annual yield:
40 000–50 000 t - before the Sahelian drought;
20 000 t - during the Sahelian drought, and present (see Table 3).

Potential annual yield:
45 000–80 000 t in normal (no-drought) climatic situation (Balarin, 1985).

4. STATE OF THE FISHERY (mainly after Welcomme, 1979; Balarin, 1985)

4.1 Yield

Some statistical confusion arises from the situation around Lake Chad and the Yaèrès. These are international waters with free passage of fishermen and their produce. The site of capture of any lot of fish is therefore very difficult to determine and there has undoubtedly been some duplication in recording of catches from this region. The estimated catch from the Yaèrès, equivalent to 43 kg/ha, falls within the range known from other African floodplains (i.e., 40–60 kg/ha of flooded area), but some authorities place it somewhat lower (about 11 500 t, equivalent to 25 kg/ha). The Benue River catch of about 3 000 t appears to be close to the maximum potential. Forest rivers produce a combined catch of about 2 000 t. Some of the small crater lakes support fisheries, but catch data is unavailable.

Inland capture fishery is a non-industrial, artisanal industry which forms one of the main activities of the rural economy throughout Cameroon. Although accurate statistics are not possible, production is believed to have stabilized around 40–50 000 t/yr from 1970 to 1978. However, the recent Sahelian drought dramatically decreased the inland production to an estimated 20 000 t/yr. The actual status of the fishery is not really known. A composite picture for 1982 is proposed in Table 5, together with estimates of potential.

Table 5. TOTAL INLAND FISH PRODUCTION IN 1982
(adapted from Balarin, 1985)

^a Min.Econ.Plan (1981)
^b FAO (1979)
^c FAO, Fisheries Statistics
^d Satia (pers.comm.)
^e Vincke (pers.comm.)
^f SOGREAH (1982b)
^g Welcomme (1979)

Fish farming in Cameroon has a long history but is largely practiced at a subsistence level; few large farms exist and production is low. National production is modest and does not significantly contribute to the national requirement.

SOGREAH (1982b) suggests an aquaculture production of 23 t/yr, while Satia (pers.comm.) is of the opinion that the total is close to 200 t/yr; this is close to the 1982–1987 estimates of Vincke (1989, pers.comm.), with production varying from 124 to 282 t/yr (see Table 6).

Table 6. PRODUCTION FROM AQUACULTURE IN CAMEROON, BY SPECIES (t)

Source: Vincke (1989, pers.comm.)

4.2 Factors influencing yield

Several factors affect the yield in Cameroon. Firstly, the forest rivers are mostly blackwater rivers and are generally unproductive. Thus, although there is a very extensive network of large rivers in the south of the country, they do not contribute much to the potential. Secondly, the recent Sahelian drought caused the reduction in area of Lake Chad and failure of the floods over the Yaèrès. This has meant loss of the Yaèrès fishery and, after a temporary increase in catch, a loss in production and potential in Lake Chad.

There is a lack of understanding in the importance of regulation explosives and poisons being used. A shortage of trained personnel to supervise and offer advice, as well as poor supply of equipment and absence of marketing infrastructure for shipment to distant markets, hamper development.

4.3 Future development possibilities

The future of capture fisheries depends very much on the climatic developments of the Sahelian region. Improvements cannot be anticipated during the Little Chad phase but, with the restoration of a period of higher rainfall, stocks may once again build up both in the lake and on the Yaèrès floodplain. Such a rebirth of the fishery may well be endangered by the proposed development of the Yaèrès for irrigated agriculture.

5. KEY BIBLIOGRAPHY

Balarin, 1985

6. WATER BODIES DIRECTORY

(Physico-chemical data of various rivers are given in Table 8.)

LAKE BALENG

LAKE BAMBILI

LAKE BAROMBI KOTO (= KOTTO)

LAKE BAROMBI MBO (= KUMBA)

LAKE BENAKUMA

Fig. 2. LAKE CHAD
(Welcomme, 1972)

LAKE CHAD
(International water)

The catch from Cameroon waters prior to the Sahelian drought was circa 5 000 t (Welcomme, 1979).

Potential annual yield:

Table 7. CHEMICAL COMPOSITION OF WATERS DURING “NORMAL” CHAD PERIOD IN MAIN LAKE ZONES
(cited in Leveque, 1987)

Values are in meq/l when not otherwise specified.
Values between parentheses () are approximate and deducted from evaporation experiments.

LAKE DEBUNDSHA

LAKE DISSONI (= SODEN)

LAKE EJAGAM

LAKE FIANGA
(International water)

LAKE MBOANDONG

LAKE NYOS

LAKE OKU

LAKE TIBATI

LAKE TIZONO

BENUE RIVER AND FLOODPLAIN
(International water)

Physical and chemical data (see Table 8)

CHARI RIVER AND YAERES FLOODPLAIN
(International water)

Fisheries data

Total annual catch: the catch from the Chari/Logone system, which originates mainly from the Yaèrès floodplain (4 600 km²) was estimated (in the early 1960's) at 20–30 000 t from Cameroon and 35 000 t from Chad (Blache & Miton, 1962). The status of this fishery changed during the Sahelian drought, when much of the plain was left unflooded.

Potential annual yield: 12 500 t in Yaèrès floodplain (Sources: see Table 1)

CROSS RIVER
(International water)

LOGONE RIVER AND YAERES FLOODPLAIN
(International water)

SANAGA RIVER

SANGHA RIVER
(International water)

BAMENDJING RESERVOIR

BINI RESERVOIR

DANG RESERVOIR

EDEA RESERVOIR

LAGDO RESERVOIR

MAGA RESERVOIR

MAYO OULOU RESERVOIR

MBAKAOU RESERVOIR

SONG-LOULOU RESERVOIR

Table 8. ANALYSES OF RIVER WATERS - CAMEROON
(SOGREAH, 1983a)

* Total dissolved solids

7. BIBLIOGRAPHY

Aubray, 1976
Balarin, 1985
Bell & Canterbery, 1976
Blache et al., 1964
Blache & Miton, 1962
De Kimpe, 1980a,b; 1983
Durand, 1980
Dussart, 1969
FAO, 1979
Grover, Street & Starr, 1980
Laclavere & Loung, 1980
Leveque, 1987b
Min. Econ. Plan, 1981
Moses, 1982
Njock, 1979
SOGREAH, 1982a,b,c; 1983a,b,c
Stauch, 1966; 1977
Van der Meeren, 1980
Welcomme, 1972; 1979