COUNTRY REVIEWS

ANGOLA

Angola is divided into (a) Angola proper, which lies south of the Zaire river between 6° and 17°S and 12° and 23°E, and (b) Cabinda, a small exclave lying on the coast to the north of the Zaire River. The major part of Angola is a central plateau of between 1 000 and 1 600 m in altitude, rising in the west-central region to highlands 2 000–2 500 m high. There is a narrow coastal plain. The northern part of Angola is covered with rain forest, the south is savanna merging into semi-arid desert. Cabinda is low-lying, tropical and densely forested.

5. CLIMATE

In general the north of Angola is tropical in climate, whereas the south is semi-arid. The climate is largely conditioned by the cold Benguela current and gives a temperate character to the coastal regions. There are two main seasons, a cold, dry season from May to October, and a warm, wet season from November to April. During the cold period temperatures can drop to freezing on the plateau.

6. HYDROLOGY

6.1 Rivers

The country is on the whole well-watered by rivers draining the central highland plateau. Poll (1967) assigns the rivers to five main basins corresponding to zoogeographical regions. These are:

1. the Zaire River basin where major tributaries include the Kasai and Kwango Rivers;

2. the Zambezi River basin with the headwaters of the Zambezi and its tributaries the Lungue and Cuando Rivers;

3. the Okavango River basin, with the Cuito and Cubango Rivers;

4. the northern coastal rivers chief of which is the Cuanza River;

5. the Cunene River basin.

The major river channels total over 10 000 km in length without counting small streams.

6.2 Lakes

There are no large lakes in Angola, but there are numerous smaller bodies of water associated with the river systems in the south and east of the country.

7. LAND AND WATER USE

Angola is a predominantly agricultural country with some mining in the north-eastern region. There are few reservoirs or impoundments and so far there is no extensive use of water for irrigation.

8. FISHERY YIELD/PRODUCTION

Table 2

Nominal catches in the inland waters of Angola (1971–76)

The zero catch quoted in Table 2 means only that no information is available at the present time on the catch from the inland waters of Angola.

9. STATE OF THE FISHERY

9.1 Yield

The lack of figures and reported catches from Angola almost certainly present a false picture of the importance of inland fish and fisheries. If it is assumed that artisanal fisheries are pursued on all water courses, as they are in most of Africa, and if the catches are of the same order of magnitude, an estimate of at least 10 000 t is obtained by application of the simple rule of thumb for yields from African rivers derived in Welcomme (1976). Obviously, this figure cannot be advanced with any security, but it does suggest that there is a potential or actual yield from inland fisheries that is of some importance.

9.2 Factors influencing yield

As most of the inland waters are rivers the yield would be sensitive to any management work aimed at controlling flow, such as irrigation projects or dam construction. Furthermore some of the rivers are in densely forested areas and are probably relatively unproductive.

9.3 Forecast

Lack of information on the fisheries makes it difficult to judge the condition of the fish stock. The inland fishery sector is unimportant relative to the very extensive marine fishery, hence little attention has been paid to it. It is likely, however, that more emphasis will be placed on this sector as development of the hinterland increases.

10. SPECIFIC REFERENCES

Poll, M., 1967 Contribution à la faune ichtyologique de l'Angola. Diamang Pub.Cult., 75 Lisboa. 381 p.

BENIN

Benin is divided into four natural regions: (a) a flat sandy coastal plain which is transected by brackishwater lagoons; (b) a granitic plateau which occupies most of the centre of the country and rises toward the Atacora mountains in the northwest; (c) the valley of the Pendjari River and (d) the valley of the Niger River.

5. CLIMATE

The coastal region of the country is hot and humid with a moderately even temperature throughout the year. There are two rainy seasons, a major rain from March to June and a minor one peaking in October. The country becomes more arid with a cool period in December and January and a hot period between March and June. Rainfall is concentrated into one season between July and October.

6. HYDROLOGY

6.1 Rivers

Hydrologically the country can be divided into three main drainage areas: (a) to the north Benin borders on the Niger River for about 120 km and the three main mid-course tributaries of that river, the Alibori, Sota and Mekrou Rivers, arise on the central plateau of Benin to flow torrentially northward into the Niger. The Benin bank of the Niger has a broad floodplain covering about 270 km² at peak floods; (b) the Pendjari River, a tributary of the Volta, drains the western slopes of the Atakora mountains and runs for some 400 km through Benin before entering Togo; (c) the south-flowing rivers, the Mono (360 km), Couffo (240 km) and Ouémé (700 km) arise on the central plateau and below torrential upper courses form broad fertile floodplains in the coastal zone. The floodplains terminate in a series of extensive lagoons. The greatest of the floodplains, that of the Ouémé, extends over 2 000 km² at peak floods.

6.2 Lakes

There are several groups of lakes associated with the floodplains of the south-flowing rivers. On the Ouémé there are Lakes Azilli and Cele, both of which cover about 5 km². On the Mono there are about six lakes which covered a total of 16 km² in 1971, but siltation and other changes due to management of this basin are altering their characteristics very rapidly.

6.3 Reservoirs

There are no major reservoirs in the country although there are several small cattle dams in the north.

6.4 Brackish waters

By far the most important bodies of water in the country are the brackishwater coastal lagoons which are contiguous with the whole lagoon system of the West African coast. There are two major lakes, Lake Nokoue-Porto Novo lagoon, which together cover about 14 700 ha and are separated only by the numerous channels of the deltaic fan of the Ouémé River, and Lake Ahémé which covers 8 500 ha. Smaller lagoon systems covering about 2 800 ha connect the major bodies of water with the sea, and run parallel to the coast behind the dune systems.

7. LAND AND WATER USE

Benin is an agricultural country. The south concentrates on plantations of oil palm and to the north the main crops are maize and cotton. Cattle are abundant, particularly on the floodplains of the Niger in the north and the Ouémé in the south. There is a considerable amount of drawdown agriculture on the floodplains in the south and rice cultivation has recently been introduced in the Ouémé.

8. FISHERY YIELD/PRODUCTION

Table 3

Nominal catches in the inland waters of Benin (1971–76)
(in tons)

The Direction des Pêches (1977) gives a more extensive series of records over 18 years from which the information given in Table 4 may be extracted.

Table 4

Comparison of catch by water body in Benin between 1959 and 1976

9. STATE OF THE FISHERY

9.1 Yield

The figures in Tables 3 and 4 indicate a general trend in production from the inland waters of Benin whereby the catch has declined by nearly 50 percent over a period of 20 years.

9.2 Factors influencing yield

Losses have occurred in the four main fisheries of the country for a variety of reasons. In the Niger River the decline was provoked, at least initially, by the failure of the main markets for fish from this region. However, the Sahelian drought also exercised a serious effect as indicated by the smoked fish landed at Malanville market during the drought years.

Table 5

Smoked fish passing through Malanville market

In the Ouémé basin, long and intensive exploitation affected the fishery whose catch dropped from about 10 000 t/y prior to 1960 to about 6 000 t/y in 1976. That overexploitation was responsible is indicated by the disappearance of the larger species of fish and the decline in the mean size of the fish caught. Changes in salinity of the lower reaches of the river, caused by the permanent opening of Lake Nokoué to the sea, have also been implicated, but do not satisfactorily explain the changes in catch that have occurred.

There is, however, no doubt that changes in salinity were responsible for the collapse of the most important fishery on the lake. Thus, the acadja fishery used extensive areas of brush parks to rear and capture fish, giving yields as high as 10 t/ha of park in the late fifties. Subsequently invasion of the lake by teredo worms destroyed or rendered uneconomic large areas of parks, and placed greater fishing pressure on the other fish stocks which in their turn have collapsed.

The fall in catch in Lake Ahémé from 8 000 t in 1970 to about 5 000 t in 1976 coincides with the removal of acadjas from that lagoon for political reasons.

9.3 Forecast

The history of the fisheries of Benin represents a classical example of past mismanagement of various types. Nevertheless future possibilities could be moderately good. A return to a pluvial phase in the Sahel could increase production from the Niger river to its previous high level, if suitable markets for the products can be found.

In the lagoons previous production levels could possibly be restored. In Lake Ahémé, the simple reintroduction of acadjas in a planned fashion would probably bear immediate results. In Lake Nokoué, the need to control the penetration of sea waters into the lagoon is paramount, and the recent construction of a barrage across the channel at Cotonou to the ingress of sea water might permit the lake to be used as a vast fish culture pond.

In the Ouémé, however, the prospects are somewhat bleak. The fishery is already overexploited and the valley is densely populated so it is difficult to see that the pressure will be relieved. Furthermore, the floodplain of the Ouémé is now being increasingly used for rice culture and the drain-in fish ponds, which contributed much to the fishery are being abandoned. There will almost certainly be an attempt to control the Ouémé floods with an upstream dam in the future and with that the fishery will be lost as a consequence.

A part from the natural water bodies, considerable increases in production of fish from Benin can be foreseen with the successful introduction of brackishwater aquaculture into the coastal belt.

10. SPECIFIC REFERENCES

FAO,1971 Rapport au Gouvernement du Dahomey sur l'évolution de la pêche intérieure, son état actuel et ses possibilités, établi sur la base des travaux de R.L. Welcomme, Spécialiste de la pêche. Rep.FAO/UNDP (TA), (2938):97 p.

Direction des Pêches,1977 Evolution de la pêche dans les eaux intérieures du Bénin. Paper submitted by CIFA Symposium on river and floodplain fisheries. Bujumbura, Burundi, November 1977. CIFA/77/Symp. 2, 18 p.

BOTSWANA

Botswana is a vast tableland of mean altitude 1 000 m, but in the north and northwest several depressions are associated with the drainage patterns of the main rivers. The country is generally arid savanna grading into the Kalahari Desert to the west. The Okavango Depression in the northwest is somewhat better wooded and is generally moister.

5. CLIMATE

Most of the country is dry with hot summers and cold winters and in the desert regions winter temperatures (May–August) can fall below zero at night. The late summer (February–April) is the wettest time of the year, but there is great variability from year to year. Flooding of the Okavango depends as much on the rainfall in the upper catchment in Angola which may be very different from that in Botswana. Most of the water in the Okavango Delta is lost by evaporation.

6. HYDROGRAPHY

6.1 Rivers

The Okavango and its terminal delta are the only aquatic systems of any importance in the country. The Okavango River enters Botswana from Angola after crossing the Caprivi strip, and almost immediately spreads out into fan-shaped delta which covers about 10 000 km². The delta is endorheic and only has outflow in exceptional years when part of the flow drains into the Zambezi system by way of the Selinda Spillway and the Linyati River and into the Mababe Depression by way of the Khwai River. The Mababe Depression may also be flooded from the Zambezi River via the Savuti River. Some water also moves down the Boteti River toward the Makgadikgadi Depression although this has not flooded in recent years.

6.2 Lakes

The only lake of any size in Botswana is Lake Ngami which forms the terminal sump of the Okavango Delta. It is fed by the Thamalakhane River but is not filled every year. Indeed the lake was dry for many years prior to 1951 and was again dry in 1973–74. When flooded the lake can reach up to 200 km² in area and 3.5 m in depth.

7. LAND AND WATER USE

The Okavango Delta area is used for subsistence farming either as dry agriculture or floodplain agriculture. Much of the basin is still occupied by wildlife as population densities are very low. At present there are no irrigation schemes although some are being proposed. All aspects of the ecology and development of the Okavango swamp have been described by Botswana Society (1976).

8. FISHERY YIELD/PRODUCTION

Table 6

Nominal catches in inland waters of Botswana (1970–76)
(in tons)

9. STATE OF THE FISHERY

9.1 Yield

The yield figures quoted in Table 6 are estimated of catch and as yet there has been no systematic survey although Gilmore (1977) also quotes an annual offtake of 1 200 t. The fishing is however pursued as a subsistence activity and few markets exist for an increased production due to poor communications in the country. Estimates of potential from the area on the basis of catches from the similar areas in Africa would suggest that catches could be considerably higher than at present.

9.2 Factors influencing yield

There is still some doubt as to whether the Okavango Delta can perform at the same level of productivity as other African floodplains. The mean of 40 kg/ha drawn from a sample of these would predict a catch of about 40 000 t/y, but the waters are more than usually poor, there are dense growths of vegetation and the main flood season coincides with the cold season, at least in the southern half of the system. Catch levels are, therefore, expected to be somewhat lower than in other comparable systems. However, even if the same potential as the adjacent Kafue system is adopted (15 kg/ha) a yield about 10 times that presently obtained could be expected (i.e., 15 000 t).

9.3 Forecast

Because of the high potential catch relative to present production, increases in yield can be anticipated in the near future.

10. SPECIFIC REFERENCES

Botswana Society, 1976 Proceedings of the Symposium on the Okavango delta and its future utilization. Botswana, Gaberone, the Botswana Society, 349 p.

Gilmore, K.S., 1977 National report on the river and floodplain fisheries of the Okavango delta, Botswana. CIFA/77/Symp. 16, 4 p.

BURUNDI

Most of the country consists of grassy uplands and hills reaching to an altitude of 2 600 m. The Ruzizi Valley and the very narrow shores surrounding Lake Tanganyika in the west are somewhat lower in altitude.

5. CLIMATE

Although it is situated just south of the equator the upland temperatures of Burundi are low because of its altitude. The Ruzizi Valley and the shores of Lake Tanganyika are somewhat warmer. There is a short dry season in January with a major rains from February to May. The major dry season lasts from May to September and is followed by a second rainy spell.

6. HYDROGRAPHY

6.1 Rivers

There are no rivers in Burundi of importance to fisheries. The Ruzizi River which flows from Lake Kivu toward Lake Tanganyika is relatively small and swift flowing. In the northern part of the country the tributaries of the Akanyaru River drain toward the Kagera in Rwanda and eventually Lake Victoria in Tanzania.

6.2 Lakes

The largest body of water in Burundi is the northeastern corner of Lake Tanganyika. About 2 600 km² of this lake lie within the boundaries of the country and this represents about 8 percent of its total area. The lake is very deep and the shoreline plunges steeply downward. There are some small lakes in the north of the country associated with the Akanyaru River. Largest of these are Lakes Cyohoha S. and Rugwero, which are situated between Burundi and Rwanda. Three smaller lakes, Kazigiri, Riwihinda and Camirinda complete the series.

7. LAND AND WATER USE

Burundi is occupied by pastoral peoples who have settled the hills. There is also intensive agriculture and coffee is the main cash crop. There is some irrigated agriculture within the Ruzizi Valley which involves heavy applications of pesticides.

8. FISHERY YIELD/PRODUCTION

Table 7

Nominal catches in the inland waters of Burundi (1966–76)
(in tons)

9. STATE OF THE FISHERY

9.1 Yield

Practically all of the fish caught in Burundi comes from Lake Tanganyika. Only small amounts of fish for local consumption are taken from the lakes in the north of the country. There are three main types of fishery on Lake Tanganyika, a ‘pêche coutumière’ operated from dug-out canoes using hand nets. seine nets and gill nets, a ‘pêche artisanale’ operating from catamarans using lift nets, and a ‘pêche industrielle’ operating from larger vessels using purse seines. The two latter categories and to some extent the first fish for ‘Ndagala’ with light attraction. The ‘pêche coutumière’ also fishes beach seines for small cichlids. The mainstay of the fisheries is the ‘Ndagala’ which consists of three main species, Limnothrissa miodon, Stolothrissa tanganicae and Luciolates stappersii.

The FAO project for research into the lake fish stocks (FAO/UNDP, 1977) estimated that the mean sustainable yield from the lake fisheries would be about 17 000 t/y and as such the present catch levels (Table 7) are at this level.

9.2 Factors influencing yield

The fishery in Lake Tanganyika concentrates on a stock of pelagic fish whose density probably depends on the concentrations elsewhere in the lake. At present Burundi in the north, and Zambia in the south, are the only areas of the lake where catches are approaching the maximum that can be predicted. By far the greater part of the lake is still exploited at a relatively low level. As exploitation increases generally the Burundi catch may be affected. The low catches recorded in 1972 and 1973 were due to a period of social unset in the country.

9.3 Forecast

As the Lake Tanganyika pelagic fishery is approaching maximum exploitation it is difficult to see that the production of freshwater fish in Burundi can be increased. The northern lakes are too small and the nonpelagic stocks of fish in Lake Tanganyika are not abundant.

10. SPECIFIC REFERENCES

FAO/UN, 1977 Recherches halieutiques sur le lac Tanganyika, conclusions et recommandations du projet. FF:DP/BDI/73/020, 30 p.

CAMEROON

Cameroon is divided into four distinct topographical regions: (a) in the south there is a low coastal plain covered with equatorial rain forests; (b) in the centre there is a transitional plateau which rises to the north to the Adamaoua Mountains; (c) to the west there are mountain forests peaking in Mt. Cameroun (4 050 m); (d) to the north of the Adamaoua range, rolling savanna slopes gradually down to the marshlands surrounding Lake Chad.

5. CLIMATE

The climate is as varied as the topology 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. The arid north has one short rainy season from June through August.

6. HYDROGRAPHY

6.1 Rivers

Rivers from Cameroon drain into four major basins: (a) in the southeast the Woumo and Dja Rivers drain into the Sangha, a tributary of the Zaire; (b) in the south-centre the Sanaga River (975 km) drains the Adamaoua Mountains to flow into the Atlantic near Douala; (c) the Adamaoua range is drained northward by the Benue River, whose main stream and tributaries total about 1 000 km, and (d) the Logone River and its tributaries, some of which also rise in the Adamaoua range, flow northward to join the Chari before it flows into Lake Chad. There are extensive floodplains, the Yaérés, flanking the Logone for much of its lower course and these cover about 7 000 km² at peak floods. These swamps are drained by seasonal rivers such as the El Beid and the Serbewell. Several smaller rivers, including the Nyong (450 km) and the Ntem drain into the Atlantic.

6.2 Lakes

Part of Lake Chad lies in Cameroon, but because of the considerable variability in the extent of this lake it is difficult to estimate what proportion of it actually lies in the country. In its ‘Greater Chad’ phase, the lake covers about 22 000 km² of which 1 800 km² (8 percent) lie in Cameroon. During the ‘Small Chad’ phase, the lake only covers about 2 000 km², but the Cameroonian waters, which lie around the mouth of the Chari and El Beid Rivers, have been affected relatively less by the drought and still cover about 600 km² open water (i.e., about 30 percent of the lake).

6.3 Reservoirs

There are two large reservoirs in Cameroon, Lake Mbakao (or Lake Tibati) which covers an area of 600 km² at maximum flood, but often dries completely at low water, and Lake Bamendjing, which varies between 150–300 km². Both are headrivers of the Sanaga system. Two further dams have been proposed: (a) on the Benue at Lagolo and (b) on the Logone River.

6.4 Brackish waters

About 1 000 km² of the indented coastline around the Wouri Estuary is covered with mangrove.

7. LAND AND WATER USE

Cameroon is a primarily agricultural country with hardwood production in the forested areas. Demand for water for irrigation is limited. The other 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 Yaérés floodplain downstream of the suggested Logone River dam.

8. FISHERY YIELD/PRODUCTION

8.1 Capture fishery

Table 8

Nominal catches in the inland waters of Cameroon (1971–76)
(in tons)

There is a lack of reliable statistics from Cameroon, and the production figures are therefore in Table 8 in the nature of ‘guestimates’. Perhaps the most reasonable estimations of yield made before the Sahelian drought assigned the production as in Table 9.

Table 9

Production by water body in Cameroon before the Sahelian Drought (in tons)

8.2 Aquaculture

Cameroon is one of the few nations in Africa where aquaculture has made any great impact. There are again, unfortunately, no reliable figures, but in the western area of the country peasant aquaculture is very widely practised and yield from this source makes a large but not defined contribution to the natural production of fish.

9. STATE OF THE FISHERY

9.1 Yield

The total derived from tha analysis by area is 10 000 t less than that quoted in Table 8. Much of this may be accounted for in the catch from the reservoirs and in aquaculture, although it is doubtful whether these together could provide all of the discrepancy. Some statistical confusion also arises from the situation around Lake Chad and the Yaérés. 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 Yaérés, 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) (Stauch, pers. comm.).

9.2 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, more recently, the Sahelian Drought caused the reduction in area of Lake Chad and the failure of the floods over the Yaérés. This has meant the loss of the Yaérés fishery and after a temporary increase in catch a loss in production and potential in Lake Chad.

9.3 Forecast

The failure 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 Yaérés floodplain. Such a rebirth of the fishery may well be endangered by the proposed development of the Yaérés for irrigated agriculture.

CENTRAL AFRICAN EMPIRE

Essentially a well-watered plateau, the uplands of the Central African Empire (c. 1 500 m altitude) serve as a watershed dividing the Chari Basin from that of the Oubangui/Zaire. Most of the country is open savanna tending to become more arid toward the north. There is some rain forest in the extreme southwest which grades into semi-desert in the northeast.

5. CLIMATE

The climate is fairly consistent over most of the country with rains well dispersed throughout the year. There is, however, a drier period from December through April and a wetter period from May through October.

6. HYDROGRAPHY

6.1 Rivers

The Central African Empire is divided into two main watersheds. To the south there is the Zaire Basin, where the Oubangui, together with its headstream the Mbomou forms the southern border of the country for over 1 000 km, and is fed by numerous small rivers. The Mambere drains into the Sangha River which also feeds the Zaire. To the north two main blocks of rivers flow toward the Chari River. In the northeast there is the Vakaga and in the northwest the Bamingui and Ouham.

7. LAND AND WATER USE

The Central African Empire has an entirely agricultural economy with a largely rural population most of which is concentrated in the south of the country. There are large tracts of wild and uninhabited land.

8. FISHERY YIELD/PRODUCTION

8.1 Capture fisheries

Table 10

Nominal catches in the inland waters of Central African Empire (1970–76)
(in tons)

* FAO estimate

8.2 Aquaculture

There is a small but significant yield from aquaculture which is now widely spread in the south of the country. In 1974, 43 t were produced in ponds.

9. STATE OF THE FISHERY

9.1 Yield

The nominal catch figures for 1975 in Table 10 were derived as follows: Oubangui River Basin, 1 800 t/y; northern floodplains, 6 080 t/y. Fish flour from Am Dafok equivalent to 100 t of fresh fish per year.

9.2 Factors influencing yield

The rivers of the Oubangui Basin are reputedly not very productive. They have no true floodplain and their fisheries are unable to meet the demand for fish in Bangui. The northern floodplains are quite productive and could probably produce more fish. They are, however, far from the main centres of population and are badly served by roads.

9.3 Forecast

Inland fisheries should increase in importance in the Central African Empire over the next few years. The productivity of the northern floodplains may be realized to a greater extent and aquaculture could eventually make a significant contribution to the total catch.

CHAD

Chad is shaped like a shallow basin cut in half. Lake Chad itself lies at the bottom with an altitude of 280 m. The land rises to the north, where the Tibesti Mountains reach altitudes of even 3 400 m, to the east to the highlands of Sudan and to the south to the Chari watershed. The southwest of the country is heavily wooded but rapidly becomes desertic toward the north.

5. CLIMATE

Most of the southern Chad has a prolonged rainy season where the heavy rains last from April through October. Nearer the centre of the country the season becomes shorter, June to September, and north of Lake Chad there is little rainfall.

6. HYDROGRAPHY

6.1 Rivers

The whole of southern Chad is dominated by the Chari River system, which with its main tributaries, the Salamat and Azoum Rivers, extend over about 1 200 km. There are extensive swamps over most of the Chari Basin which are drained by such rivers as the Erguig and Aouk. These swamps have been estimated as covering about 80 000 km². The Chari combines with the Logone to discharge into Lake Chad.

6.2 Lakes

Lake Chad fluctuates in area in a pronounced cycle thought to be some 25 years long. This lake exists in two phases; the Greater Chad in pluvial periods, and the Lesser Chad in drought. During its Greater Chad phase, half of the lake's 22 000 km² lies within the country. In its present (1978) diminished state about 1 200 km² of the remaining 2 000 km² of open water are left around the mouth of the Chari River. Apart from Lake Chad itself there are several smaller lakes. In the Chad Basin there are Lake Iro, situated on the Salamat River floodplain which extends over 200 km², and Lake Fitri, a Lake Chad in miniature to the east of the main lake, which extends over 420 km² but can reach 1 200 km² in the rainy season. There are a further four small lakes lying along the Toubouri Depression of the Mayo Kebbi River in the flood season, but during the dry period are much smaller. Lake Tikem has an area of 15 km²; Lake Fianga, 30 km²; Lake Lere, 42 km², and Lake Trene, 12 km².

7. LAND AND WATER USE

The south of Chad has an agrarian population living mainly on subsistence agriculture. The north is desert and inhabited only by nomadic tribes. The Sahelian transitional savanna is used mainly by pastoral peoples for grazing cattle, sheep and goats.

8. FISHERY YIELD/PRODUCTION

Table 11

Nominal catches in the inland waters of Chad (1971–76)
(in tons)

Considerable statistical confusion arises from the situation around Lake Chad. The best estimates of production from the whole basin over the last few decades give the values in Table 12 which are at best speculative.

Table 12

Estimates of total production from the Lake Chad Basin
(in tons)

Source: Stauch (1977)

These estimates correspond roughly to the figures advanced by the Government of Chad as reflected in the nominal catches (Table 11). It may be assumed, therefore, that Chad has laid claim to the total production from the Lake Chad Basin, whereas in fact only a proportion of the catch originates within Chadian territory. In the case of the lake, Chad has between 50 and 60 percent of the waters although these are among the richest and most productive. Furthermore Cameroon probably produces between 20 000 and 30 000 t from the Yaérés floodplain and the river production should be diminished by this amount. Seen in this light the Republic of Chad was probably producing about 50 000 t of fish in the fifties, 70 000 t in the sixties, up to 100 000 t during the earlier years of the drought and about 50 000 t at present.

9. STATE OF THE FISHERY

9.1 Yield

The present state of the fishery of Lake Chad is very poor. The lake itself has never recovered from the 1972–74 drought and is still in its small phase. The fish population of the rivers were damaged by the changes in flood regime during the droughts and the fisheries there are also diminished.

9.2 Factors influencing yield

As with the other countries of the Sahelian belt, the main factor influencing the fishery is rainfall. This has had an especially severe effect during the latest dry period when catches rose sharply as the lake shrunk (1972–73) but fell sharply as the stocks of the new small lake were unable to support the intensive effects of the same number of fishermen who were previously dispersed over 10 times the area. In the rivers too the failure of two or more successive floods virtually exterminated several of the major migratory species leading to a disequilibrium in population structure which has not yet righted itself.

9.3 Forecast

No amelioration of the fisheries in the Lake Chad Basin can be anticipated so long as the present hydrological regime persists. However, historically the lake has always recovered from these dry spells and it can be expected to regain its large Chad phase of 22 000 km² during the next wet cycle. In that case the potential catch might be expected to exceed past yield (at 100 kg/ha the lake should produce over 200 000 t), but only if the fishery relaxes its intensity sufficiently for the fish stock to build itself up. The ploodplains too can be expected to return a better yield although the potential needs clarification (at as little as 10 kg/ha the 9 million hectares of the Chari Logone floodplains could produce 90 000 t).

10. SPECIFIC REFERENCES

Stauch, A., 1977 Fish statistics in the Lake Chad basin during the drought (1969–1976). Cah.ORSTOM, sér. Hydrobiol., 11(3):201–16

CONGO

The Democratic Republic of Congo can be divided into four topographical regions: (a) there is a coastal plain which extends about 60 km inland to the foothills of the Mayombe Mountains; (b) the Niara and Ogoué Valleys of the south-centre lie between the mountains; (c) the Bateke Plateau which serves as watershed to the Ogoué and some of the feeder streams of the Zaire system, and (d) the Zaire Basin which occupies the whole of the north of the country. There is some dry savanna in the centre of the country but most of it is covered with dense rain forest.

5. CLIMATE

There is one long rainy season which lasts for eight months of the year and peaks in April and November. The dry season lasts from June to September. Temperatures are even but reach a minimum during the dry period.

6. HYDROGRAPHY

6.1 Rivers

The River Zaire forms the frontier between Zaire and Congo for over 500 km of its lower course. The frontier continues for a further 500 km up the Ubangui. The hinterland of these rivers forms a vast marshland with extensive seasonal savanna floodplains and permanent flooded gallery forests. The area which covers about 30 000 km² is drained by the River Sangha, the Likouala and the Likouala aux Herbes as well as by numerous smaller rivers. Several other river systems exist but their importance is relatively slight.

6.2 Lakes

There are no true lakes of any size although Brazzaville is located on the Stanley Pool a lakelike enlargement of the Zaire River.

7. LAND AND WATER USE

Congo is primarily an agricultural country although it also has a considerable forestry industry.

8. FISHERY YIELD/PRODUCTION

8.1 Capture fisheries

Table 13

Nominal catches in the inland waters of Congo (1971–76)
(in tons)

9. STATE OF THE FISHERY

9.1 Yield

There is little doubt that the present catch from the Congo is very low, although it may well be higher than that reported as the nominal catch (Table 13).

9.2 Factors influencing yield

There is little doubt that the potential for increased catch is very great. The main fishery is at present concentrated on the Stanley Pool. The main floodplains of the Zaire Basin are otherwise not fished because of their inaccessibility and low population densities.

9.3 Forecast

The floodplain complex of the Sangha/Likouala Rivers is possibly one of the most important undeveloped inland fisheries in Africa. The 30 000 km² of floodplains are mainly savanna and although the gallery forests and flooded rain forests are covered with blackwaters, the savanna plains are flooded by whitewaters. A conservative estimate of potential (20–30 kg/ha) would give an estimate of yearly catch of 60 000–100 000 t. Because of its inaccessibility and the difficulties of operating there, the development of the area may take some time.

EGYPT

Egypt is an almost rainless block of desert consisting of high plains and hills in the east and along the Nile Valley. The Nile River forms the main axis of the country and stretches some 1 300 km from the Sudan border to the Mediterranean. It can be divided into two main areas, the delta which extends as far as Cairo and the rest of the Nile Valley.

5. CLIMATE

Egypt is almost totally arid and all water enters the country through the Nile. Summer temperatures are high but winter temperatures may fall as low as 10°C.

6. HYDROLOGY

6.1 Rivers

The Nile is the only river in Egypt and receives no tributaries in its course through the country. It runs for about 1 300 km from the Sudan border, although its upper course is now barred by the Aswan Dam. Below Ciaro the river splits into two distributaries, the Rossetta and Damieta branches.

6.2 Lakes

There is one natural lake, Lake Qarun, situated near El Fayum. It covers 220 km² and, although originally freshwater, its salinity has increased steadily since 1920. The lake is shallow and very productive.

6.3 Reservoirs

The Aswan Dam retains a large body of water, Lake Nasser-Nubia, which covers 3 059 km² at a level of 160 m and 6 216 km² at a level of 180 m. The equivalent values for the Egyptian portion of the lake, Lake Nasser, are 2 585 km² and 5 248 km².

6.4 Brackish waters

There are several brackishwater lagoons situated along the coastal portion of the Nile Delta. These are: Lake Manzalla, 1 450 km²; Lake Burullus, 560 km²; Lake Edku, 130 km², and Lake Mariut, 200 km². Two other low lying areas are also flooded - the port Fouad Depression, 200 km² and the Bardaweel Depression, 600 km². All these areas are very shallow, about 1 m.

7. LAND AND WATER USE

The inhabited strip of Egypt follows the banks of the Nile and expands into the delta. There is very intensive cultivation of crops as well as date palms involving extensive irrigation networks. These, together with the flood control effects of the Aswan Dam, have stopped flooding over the previous floodplain.

8. FISHERY YIELD/PRODUCTION

Table 14

Nominal catches of the inland waters of Egypt (1970–76)
(in tons)

The nominal catch (Table 14) breaks down by waterbody approximately as in Table 15.

Table 15

Catch of individual waterbodies of Egypt

9. STATE OF THE FISHERY

9.1 Yield

The steady increase in catch over the period 1970–76 has been largely due to the filling of Lake Nasser, although this alone has only added about 10 000 t to the potential of the country. There has, therefore, been a parallel development of the other fisheries. The present yield from aquaculture is estimated at about 7 000 t/y (FAO/UNDP, 1974).

9.2 Factors influencing yield

The continued high catch ratio from most water bodies in Egypt indicates that there is little overfishing at present. The coastal lagoons and the brackish Lake Qarun are extremely productive, but unfortunately have been filled in to some degree for agriculture. An extension of such land reclamation, together with the cessation of inflow of fresh waters after the closing of the Aswan Dam, may affect production in the future. Pollution by domestic sewage and agro-chemicals is also a real problem in the delta area.

9.3 Forecast

The reclamation of land around the lagoons, the extension of irrigation and the lower flow of the Nile will probably all contribute to a diminution of fish catch from this more northerly part of the system. This may be offset to a certain degree by coastal aquaculture in the lagoons. The potential of Lake Nasser is relatively high, but once fully developed production from natural waters will probably peak and then slowly decline.

10. SPECIFIC REFERENCES

FAO/UNDP, 1974 Fish yield projections in the Nasser Reservoir: Report prepared for the Government of the Arab Republic of Egypt, based on the work of R.A. Ryder and H.F. Henderson. FI:DP/EGY/55/558(5): 32 p.

ETHIOPIA

The central part of Ethiopia is a high plateau 2–3 000 m in altitude with occasional peaks reaching as high as 4 600 m. The plateau slopes away to the west toward the Somalian plains. The country is split diagonally by the Great Rift Valley.

5. CLIMATE

Generally temperate on the plateau, the climate becomes hot and arid on the lowlands and is desertic in the northeast and the south. On the plateau there is a short wet season from February to April and a major rainy season from June until September.

6. HYDROLOGY

6.1 Rivers

The Blue Nile (Abbai) River takes its source from Lake Tana and flows for about 760 km through Ethiopia. It is torrential and steeply encased by mountains for much of its course. The Awash River rises near Addis Ababa and flows northward along the Rift Valley for over 500 km before dissipating in a complex of salt lakes and marshes (Lake Abbé and Lake Gamari).

The Omo River flows south from the central highlands for some 600 km and discharges into Lake Rudolf through a small marshy delta. Two other rivers, the Shebele (about 900 km in Ethiopia) and the Gamala (about 500 km in Ethiopia) drain the highlands toward the south and cross the Ogaden desert before entering Somalia.

6.2 Lakes

The largest lake in Ethiopia is Lake Tana which covers 3 500 km². It is moderately shallow, with a mean depth of 15 m and the waters are rich in nutrients. The remaining lakes in the country form a string along the Great Rift Valley (Table 16).

Table 16

Characteristics of the Ethiopian Rift Valley lakes

The very high conductivity of the waters of some of the lakes shows them to be the highly saline, soda-type lakes typical of the Rift Valley.

6.3 Reservoirs

There is one major reservoir in Ethiopia, the 250 km² Lake Koka which was formed by damming the Awash River.

7. LAND AND WATER USE

Ethiopia is an entirely agricultural country where intensive use of marginal lands has caused severe erosion in places. Rivers are consequently highly silted. There has been little development for irrigation except along the Awash River.

8. FISHERY YIELD/PRODUCTION

Table 17

Nominal catches in Ethiopian inland waters (1970–76)
(in tons)

9. STATE OF THE FISHERY

9.1 Yield

The nominal catch figures (Table 17) reflect the general lack of interest in the inland fisheries sector until the present. There is in fact a considerable potential from the inland waters of Ethiopia as show theoretical estimates made using the Morpho-Edaphic Index (MEI) as derived from other African lakes (Table 18). The analysis excludes those lakes with very high salt content.

Table 18

Estimated potential yield from Ethiopian lakes based on MEI

^a assuming production of 100 kg/ha

9.2 Factors influencing yield

Apart from the physico-chemical limitation of productivity in the salt lakes most water bodies appear to have considerable potential for increased yield. At present this is not realized mainly because of local food customs and the consequent lack of interest in fishing within the country.

9.3 Forecast

The main inland fisheries are within easy reach of the major urban centres and it is almost inevitable that the inland fisheries of Ethiopia will develop considerably over the next few decades.

GABON

Gabon is divided into two main zones: (a) a low-lying coastal region and (b) an interior plateau which is transected by river valleys and mountain chains of about 900 m in altitude. The highest peak is 1 550 m high.

5. CLIMATE

The climate is hot and humid with a long cold dry season from June to September, a short rains from October to December, a short dry season from December to January and a long rains from January to May.

6. HYDROLOGY

6.1 Rivers

The main river in the country is the Ogooue which rises in the highlands of Congo but flows for 1 200 km through Gabon to discharge into the Atlantic at Port Gentil. There are many other rivers draining this wet and forested country, the Nyanga, Lolo, Ivindo, Ogoula, N'Gounie, Woleu, Ofoué, Ntem and Lovetsi are all over 450 m long.

6.2 Lakes

There are several freshwater lakes associated with the floodplains of the Ogooué River. The largest of these are Lake Ezaga (52.5 km² - dry season area), Lake Onangué (167.5 km² - dry season area), Lake Oguemoue (46.5 km² - dry season area) and Lake Anengué.

6.3 Brackish waters

The coast is dotted with brackish water lagoons, including Lake Tchanga Tchini, Lake N'Gomi, Lake Iguela, Lake Nologo and Lake M'Bani.

7. LAND AND WATER USE

Gabon is very sparsely populated and the main commercial activity is forestry, the majority of the country being thickly wooded.

8. FISHERY YIELD/PRODUCTION

Table 19

Nominal catches in the inland waters of Gabon (1970–76)
(in tons)

For a country with such an extensive network of inland waters the nominal catch of 400 t quoted in Table 19 seems very low. Mougnassa (1977) advances a more reasonable figure of about 30 percent of the total national catch (6 056 t) which would put the present yield at 1 800 t, a figure completely consistent with the 1 485 inland fishermen listed as working in the country.

9. STATE OF THE FISHERY

9.1 Yield

Even at 1 800 t the yield of the inland fisheries appears very low considering the extent of the resource. It may safely be suggested therefore that the fishery is underdeveloped, an observation confirmed by Mougnassa (1977) who describes the fishery as developing.

9.2 Factors influencing yield

At present human and sociological factors seem to be keeping the fishery at a low level of productivity. Fishermen are not abundant and are badly equipped. There is little infrastructure in the form of training establishments or marketing networks or sales facilities for fishing gear.

9.3 Forecast

It is fairly certain that the inland fisheries of Gabon will develop in the future. More catch can be anticipated from the natural waters and with the recent introduction of aquaculture the production of freshwater fish could probably be doubled or even tripled.

10. SPECIFIC REFERENCES

Mougnassa, 1977 Country report on Gabon. Paper submitted to CIFA Symposium on river and floodplain fisheries. Bujumbura, Burundi

THE GAMBIA

The Gambia is a long low-lying strip of land flanking the Gambia River for the lower 480 km of its course. Nowhere does the land rise above 40 m in altitude. Much of the river is estuarine and mangroves penetrate upstream for a considerable distance. Salt water penetrates 150 km upstream in the floods and 200 km during the dry season.

5. CLIMATE

The winters are cool and summers warm. The climate is dry for most of the year with a single rainy season lasting from June to September. The flood of the river coincides with this.

6. HYDROLOGY

6.1 Rivers

The Gambia is the only river, entering from Senegal and flowing for its last 480 km through the country. Several small tributaries briefly traverse the country to discharge into the Gambia River. Most of the banks are flooded during the rains and the estimated area of waters at peak floods of 2 000 km² covers about 40 percent of the area of the country.

6.2 Brackish waters

The saline downstream reaches of the river are lined with mangroves and are generally estuarine in character.

7. LAND AND WATER USE

The Gambia is a wholly agricultural country whose activities are confined to the banks of the river. There is some rice culture, but little flood control or irrigation. On the whole the flood regime still controls the activities of the rural communities.

8. FISHERY YIELD/PRODUCTION

Table 20

Nominal catches in the inland waters of the Gambia (1970–76)
(in tons)

9. STATE OF THE FISHERY

9.1 Yield

It is evident that the nominal catch (Table 20) is low compared with the state of the resource. The Gambia River can be divided into two main fisheries. In the estuarine reaches there are heavy fisheries for Ethmalosa fimbriata, mullets and other brackishwater species. In the freshwater reaches there is a well developed floodplain fishery which concentrates mainly on characins, siluroids and cichlids. Two estimates of potential can be advanced. Firstly simply on the basis of the length of the river one would expect to find at least 2 000 t of fish per year (using Welcomme's (1975) formula). The area is however largely estuarine and also has extensive upstream floodplains, which, on the basis of 40 kg/ha (mean derived from other similar systems), would be expected to produce about 8 000 t/y. These two estimates are disparate and because of the lack of fundamental research work on the river it is difficult to decide which corresponds best to the real situation. It is in any case to be supposed that actual catches are greater than the official estimates.

9.2 Factors influencing yield

Factors which may influence yield in the future are plans to control the flood of the Gambia River which would cut down on the amount of floodland available to the fish.

9.3 Forecast

That the recorded catch of inland fish in Gambia will rise in the next few years. This may not be due so much to any actual increases in production but to improvements in statistical systems which will enable better estimates of catch.

GHANA

Ghana is divided into three main regions. There is a narrow sandy coastal plain, behind which there is a range of low but abrupt hills. To the north there are low-lying plains. The southwestern part of the country is densely forested, and to the north are bush savanna and grasslands.

5. CLIMATE

The coastal belt is warm, fairly dry to the east but becoming more humid to the west. The forest zone is very humid but the rest of the country becomes progressively more arid northward. In the south there are two rainy seasons, March–June and September–December, separated by dry periods. In the north the two wet seasons tend to be closer together and merge into one.

6. HYDROGRAPHY

6.1 Rivers

Ghana is extremely well watered and is drained principally by the Black, White and Red Volta River and the Oti River, but several smaller water courses, including the Pra, Tano and Bia, drain the forested southwestern areas.

6.2 Lakes

The only natural freshwater lake of any size in the country is Lake Bosumtwi, a crater lake of 49 km² in area.

6.3 Reservoirs

Ghana contains the largest reservoir in Africa, the 8 482 km² Lake Volta. This reservoir which is backed up behind the Akosombo high dam is over 400 km long and has drowned much of the lower courses of the various rivers of the Volta system.

6.4 Brackish waters

There are several brackishwater lagoons situated around the delta of the Volta River. The largest of these is Keta Lagoon (330 km²). The nature of the lagoons has changed considerably since the closure of the Akosombo Dam as the former periodic flushes of fresh water do not now occur and the lakes have become more saline as a consequence.

7. LAND AND WATER USE

Ghana is almost entirely agricultural except for some industry which is located mostly at Tema. The Akosombo Dam was built to provide power for the industrialization of Ghana but also supplies Togo and Benin. Forestry is also an important activity in the southwest of the country.

8. FISHERY YIELD/PRODUCTION

Table 21

Nominal catches in the inland waters of Ghana (1970–76)
(in tons)

In addition to the nominal catches given for the whole country (Table 21) there are estimates of catch which have been gathered for Lake Volta (Table 22).

Table 22

Estimated catches from Lake Volta (1969–73)
(in tons)

These figures differ from the nominal catch figures and in some years exceed them. This implies that no production is assigned to the other inland waters of Ghana.

9. STATE OF THE FISHERY

9.1 Yield

The catch from Lake Volta reached a peak of about 60 000 t in the years immediately after the lake filled. Subsequently there has been a decline to 35 000–40 000 t which seems to be stabilization level. Catch from other inland waters is unrecorded although the yield of the coastal lagoons is almost certainly quite high and the upper courses of the Volta River with their floodplains must also produce some fish.

9.2 Factors influencing yield

The yield of Volta has followed the classic pattern of peak and stabilization. The dam has undoubtedly affected the catch downstream and probably also the fisheries of the coastal lagoons. There has been little effort at introducing fish culture although the coastal lagoons are well adapted to brackishwater ponds.

9.3 Forecast

The Volta Lake will continue to provide large amounts of fish and the catch from other water bodies may be recorded giving higher nominal catches in the future. Any further real gains in production will have to be through aquaculture.

GUINEA

Guinea is divided into four main regions: (a) a narrow coastal belt; (b) the Fouta Djallon Mountains, which are on average 1 000 m high; (c) the Upper Guinean Plains, with an altitude of 300 m, and (d) a densely forested southeastern region.

5. CLIMATE

The coastal region and most of the inland areas have a tropical climate with high humidity and temperature. There are two rainy seasons. In the north the climate is sudanic with a single rainy season and greater daily and seasonal temperature variations.

6. HYDROLOGY

6.1 Rivers

Many of West Africa's great rivers rise in the Fouta Djallon Mountains. The Upper Niger has a length of 580 km within Guinea, and together with its major tributaries probably totals over 3 400 km of waterways. Other important rivers are the Gambia (210 km), the Bafing headwater of the Senegal (130 km), the Konkoure, the Kolente and many others. Aubray (pers. comm.) estimates the total length of main rivers in the country to be about 6 500 km. In addition, there are several floodplains associated with the rivers (especially the Niger) which cover about 200 000 ha during the rains.

6.2 Lakes

There are no natural lakes of appreciable size in Guinea.

6.3 Reservoirs

Five reservoirs already exist with a combined area of 3 140 ha. One larger dam is projected for the Konkoure River which will cover 50 000 ha when completed.

7. LAND AND WATER USE

Peasant agriculture, pastoralism and forestry are about equally practised in the country. Rice culture is practised in the floodplain areas of the north.

8. FISHERY YIELD/PRODUCTION

Table 23

Nominal catches in the inland waters of Guinea (1970–76)
(in tons)

The figures given in Table 23 do not reflect the true catch. Aubray (pers. comm.) noted the existence of intensive fishing activities especially in the Niger, and estimated that the catch varies between 500 and 1 000 t depending on the year.

9. STATE OF THE FISHERY

9.1 Yield

There seems to be little doubt that the present catch exceeds the official figures quoted as nominal catch. An estimate of 1 000 t has been advanced, but the extent of inland waters in the country would suggest that the potential is even higher than this, say about 5 000 t.

9.2 Factors influencing yield

The main constraint on increasing the catches of the inland fisheries in Guinea is the lack of infrastructure for marketing and distributing the produce. Competing uses of the floodplains for rice culture may limit the productivity of these regions.

9.3 Forecast

The inland fish catch in Guinea will undoubtedly rise over the next decade. The country is highly suitable for aquaculture, and the introduction and popularization of the rearing of fish in ponds would make a valuable contribution to the economy. In addition, the projected dam on the Konkoure will almost certainly add to the potential.

IVORY COAST

Nearly the whole country is low-lying and only in the northwest does the relief begin to rise toward the Guinea highlands. The southern half of the country is densely forested and the northern half consists of sparse scrub savanna growing on poor lateritic or sandy soils.

5. CLIMATE

The south of the country has a typical tropical climate with warm even temperatures and high humidity throughout the year. There is a heavy annual rainfall which is concentrated into two rainy seasons, March–July and September–December. In the south the climate is more arid with a tendency for the two rainy seasons to become amalgamated into a single season lasting from March to October.

6. HYDROLOGY

6.1 Rivers

Apart from two very short headwater tributaries of the Niger River all the rivers in Ivory Coast are south-flowing. There are three main basins which lie wholly within the country. The Sassandra River (650 km), the Bandama River (1 050 km) and the Comoe River (1 160 km). In addition the Cavally River forms the frontier with Liberia and the Bia River emerges from Ghana for the final few kilometres of its course.

6.2 Lakes

There are no natural lakes of any importance in the country.

6.3 Reservoirs

Ivory Coast has two main large reservoirs: Lake Kossou on the Bandama River which covers an area of 1 700 km² and Lake Ayame on the Bia River which covers an area of between 84 and 197 km² depending on the intensity of flooding and the stage of drawdown.

6.4 Brackish waters

There are numerous brackishwater lagoons along the coastal strip of Ivory Coast. Of these the largest is the Ebrie lagoon with an area of 532 km²; second is Abi-Tendo-Eki complex which covers 410 km². Several other smaller lagoons are dispersed along the coast.

7. LAND AND WATER USE

The Ivory Coast has a predominantly agricultural economy based on a wide range of products.

8. FISHERY YIELD/PRODUCTION

Table 24

Nominal catches in the inland waters of Ivory Coast (1970–76)
(in tons)

9. STATE OF THE FISHERY

9.1 Yield

The nominal catches seem low in view of the catches from the two reservoirs. The catch from Lake Ayamé was recorded at 1 200 t in 1969, and has presumably continued at that level in subsequent years. The catch from Lake Kossou was recorded at 903 t in 1972 and 2 202 t in 1973. Catch projections from the lake (FAO/UNDP, 1976) indicate that the production will stabilize at about 8 000 t (47 kg/ha) at an area of 1 700 km². In addition to the production from the reservoirs there are important fisheries on the main rivers which possibly produce about 3 000 t/y and also on the coastal lagoons. The lagunar production is not known but has been estimated at about 5 000 t/y. The present production from aquaculture is estimated at about 10 t/y (FAO/UNDP, 1975). Total yield from the inland waters of Ivory Coast may therefore be estimated at about 17 000 t.

9.2 Factors influencing yield

The main factor which has tended to keep the catch rates from Ivorian inland waters low is the lack of skilled fishermen within the country. Traditionally the waters have been fished by Ghanaian fishermen, but the policy of the Ivorian Government to keep foreign fishermen out of the country left a shortage of manpower. This has to a certain extent been overcome by the training of fishermen on Lake Kossou, and there is almost certainly a continued if illicit foreign presence on the various fishing grounds.

9.3 Forecast

Ivory Coast possesses a diverse inland fishery which can produce up to 17 000 t/y from the natural waters alone. Attempts to introduce aquaculture on a large scale have so far been unsuccessful, though there is no doubt that a potential exists for expansion of both fresh and brackishwater production of fish in ponds.

10. SPECIFIC REFERENCES

FAO/UNDP, 1976 Développement de la pêche dans le lac Kossou. Côte-d'Ivoire: Conclusions et Recommandations, FI:DP/IVC/71/T26, Rome, 1976, 102 p.

KENYA

The western and central parts of Kenya consist of highland plateaus which are divided from north to south by the Great Rift Valley. The plateaus are crowned by mountains of which Mount Kenya (5 200 m) is the highest. The highlands slope downward to the east.

5. CLIMATE

Kenya has a wide range of climates. The north, and much of the east of the country are desertic with little rainfall and high temperatures. The highland plateaus have warm temperate climates with two well marked rainy seasons: February–May and October–December. The coast has a monsoon climate with a prolonged wet season peaking in May.

6. HYDROLOGY

6.1 Rivers

The rivers of Kenya fall into two main groups: (a) coastal rivers - the Athi (Galana) River 560 km long with a broad floodplain in its lower reaches and the Tana River 800 km long; (b) rivers flowing into Lake Victoria of which the Nzoia River, Yala River and Sio River are the most important. Several seasonal rivers such as the Turkwell drain the western rift wall toward Lake Rudolf. Altogether FAO/UN (1966) estimated about 3 000 km of rivers in the country.

6.2 Lakes

The major Kenyan lakes fall into two main groups: (a) Lake Victoria; (b) the Rift Valley lakes. Kenya possesses 4 100 km² (69%) of Lake Victoria. A considerable portion of this is located in the shallow and productive Kavirondo Gulf. Characteristics of the Rift Valley lakes are shown in Table 25.

Table 25

Characteristics of the Rift Valley lakes of Kenya

One small lake, Lake Jipe lies between Kenya and Tanzania. About half of the lake's total 38 km² lie in each country. Many other small lakes and dams are dotted around the country, and there are several small seasonal lagoons in coastal areas at the mouths of the Tana and Galana Rivers.

6.3 Reservoirs

There is one large river on the Athi River and numerous ponds and dams scattered throughout the country. FAO/UN (1966) estimated between 12 000 and 22 000 ponds and 3 000 dams; in 1975, this area of ponds was estimated at 2 800 ha (FAO/UNDP, 1975) made up of about 28 000 individual ponds.

7. LAND AND WATER USE

The highlands of Kenya are used for agriculture, whereas the lowland areas tend to be occupied by pastoral peoples. Large areas of the country have been reserved as game parks and much of the north is desertic and supports only very limited populations.

8. FISHERY YIELD/PRODUCTION

Table 26

Nominal catches in the inland waters of Kenya (1970–76)
(in tons)

Of the nominal catch shown in Table 26, Kenya Fishery Department statistics indicate catches from the Kenyan waters of Lake Victoria as in Table 27.

Table 27

Fish catch from the Kenyan waters of Lake Victoria
(in tons)

FAO/UN (1966) estimated the production of the various water bodies in 1965 as in Table 28.

Table 28

Production of fish from the inland waters of Kenya (1965)

9. STATE OF THE FISHERY

9.1 Yield

FAO/UN (1966) projected increases in most waters to be reached by 1970. These increases, in fact, predicted a yield of about 25 000 t, a figure very similar to that quoted as nominal catch, from 1970 to 1975. Lake Victoria is exceptional in that it not only maintained its yield in the face of overexploitation but has increased it to 17 000 t. It would now appear that most inland waters are approaching full exploitation and that further increases in catch are not foreseeable from natural waters. The only exception to this is Lake Turkana.

9.2 Factors influencing yield

Lake Turkana has always remained the point of uncertainty in Kenyan inland fisheries. The lake is very isolated and the fishery has been very late in starting. It has always been assumed, due to the richness of the waters, that productivity would be high - the MEI for instance predicts catches of up to 93 000 t (about 123 kg/ha) and FAO/UN (1966) estimated the potential at between 50 000 and 160 000 t. However, more recent investigations by the Lake Turkana Investigation Team in 1975 suggested that the potential yield would be much lower than this, between 5 000 and 10 000 t.

9.3 Forecast

As the catches from most waters seem to have reached their upper range giving a total catch of about 37 000 t in 1976, the potential for further development rests mainly on the actual potential from Lake Turkana. If the potential is as low as suggested by the Lake Turkana Investigation Team, then little increase in overall production can be anticipated. Any increase over and above the present tonnage will reflect the degree to which the lake can exceed this estimate.

10. SPECIFIC REFERENCES

FAO/UN, 1966 Report to the Government of Kenya on Fishery Development Possibilities. Based on the work of D.H. Rhodes. Rep.FAO/TA, (2144):77 p.

LIBERIA

Apart from a narrow coastal strip Liberia consists of a series of plateaus of moderately high altitude within a few higher hills of up to 1 500 m. The country is densely forested.

5. CLIMATE

The climate is hot and humid with one major extended rainy season between April and November. There is very little variation in temperature which averages about 30°C.

6. HYDROLOGY

6.1 Rivers

Six main rivers flow across the country from the Fouta Djallon Mountains of Guinea. These are the Lofa River, the St. Paul River, the Saint John River, and the Cestos River which have their lower courses entirely in the country, the Mano River which forms the frontier with Sierra Leone and the Cavalla (Cavally) River which forms the frontier with Ivory Coast. In addition there are several smaller streams such as the Grand Cess River, the Sino River and the Farmington River.

6.2 Lakes

There are no large natural lakes in Liberia.

6.3 Reservoirs

There is one small hydroelectric reservoir near Monrovia.

6.4 Brackish Waters

Lagoons (such as Lake Piso - 180 km²), tidal creeks and swamps are plentiful along the coastline.

7. LAND AND WATER USE

Liberia exports iron, rubber and timber. Apart from the commodities the country is wholly devoted to small-scale agriculture.

8. CATCH

Table 29

Nominal catches from the inland waters of Liberia (1970–76)
(in tons)

9. STATE OF THE FISHERY

9.1 Yield

There is very little information on the inland fisheries of Liberia. In view of the area of fresh and brackish waters the nominal catch of 4 000 t cited in Table 29 seems low, but lacking further information it is difficult to make a forecast of potential catch.

MALAGASY REPUBLIC

The Malagasy Republic is situated on the Island of Madagascar and some smaller offshore islands. The main island consists of a central high plateau between 1 000 and 2 000 m in altitude which falls away steeply on all sides to a narrow coastal belt.

5. CLIMATE

The central islands have a temperate climate with a single rainy season from November to April. The coastal regions have a tropical climate. On the north and west coast rains are light whereas on the south and east rains are heavy and continuous throughout the year.

6. HYDROLOGY

6.1 Rivers

Many rivers flow from the central highlands of Madagascar. Most of these are torrential in their upper courses with only very small or restricted floodplains. Nevertheless Collart and Rabelahatra (1977) estimate the area of floodplain to be 91 800 ha.

6.2 Lakes

The main natural lakes in the country are listed in Table 30.

Table 30

Areas of the main natural lakes of Madagascar

6.3 Reservoirs

There are two large dams situated near the capital Antananarivo (Table 31).

Table 31

Areas of the major reservoirs of Madagascar

6.4 Brackish Waters

Madagascar has enormous brackishwater resources. These consist of lagoons on the east coast and mangrove swamps grouped around the mouths of the main rivers on the west coast (Table 32).

Table 32

Areas of the major brackish waters of Madagascar

7. LAND AND WATER USE

The country is wholly agricultural and bad land-use practices and deforestation have resulted in severe erosion problems which have lead to many of the rivers being heavily charged with silt.

8. FISH YIELD/PRODUCTION

Table 33

Nominal catches in the inland waters of Madagascar (1970–76)
(in tons)

An estimated production of about 12 300 t per year (equivalent to 130 kg/ha/y) is obtained from the commercial fisheries in the major lakes and lagoons. The yield of the subsistence fisheries is thought to be 28 000 t, giving a total yield of 40 000 t, which agrees with the nominal catch (Table 33).

9. STATE OF THE FISHERY

9.1 Yield

The estimate of 40 000 t was taken by Collart and Rabelahatra (1977) as near the maximum that can be produced from natural waters.

9.2 Factors influencing yield

The fishery has been developing at about 2 percent per year over the last 15 years. In some lakes, e.g., Lake Alaotra, accelerated development of the fishery occurred when better fishing materials were introduced. Lake Itasy was overexploited between 1960 and 1965 and the stocks did not reconstitute themselves. Many of the other areas, such as the Pangalanes are recorded to be unproductive and intensively exploited.

9.3 Forecast

No great increases in natural fish production can be anticipated from the inland and brackish waters of Madagascar. They are at present intensively exploited and need rational management to maintain their present levels of productivity. Further growth of the inland fisheries sector could occur through fish culture and/or intensive management of inland water bodies by stocking and feeding.

10. SPECIFIC REFERENCES

Collart, A. and A. Rabelahatra, 1977 Pour le recueil des données statistiques de base sur les pêches continentales. Production et commercialisation. Projet de développement des pêches continentales et de l'aquaculture, MDRRA-PNUD-FAO. Doc.Tec.FAO.Antananarivo, (MAG/76/002-1): pag. var.