2.1.1 Definition, Description and Examples
Floodplains are large flatland areas through which flow rivers whose seasonal high tides cause large-scale flooding. The principal examples are the plains of the Niger, Barotse, Benoue, Chari and Logone, Senegal and Kafue. Fish production depends largely on the extent and duration of the floods. At low water, quantities of fish corresponding to the production capacity of the flooded areas are concentrated in the minor river bed. Migrating fish also concentrate there at the beginning of the flood and are caught on a major scale.
2.1.2 Fishery Resources
Total production in the principal floodplains is estimated at about 500 000 t a year, or 30 to 35 percent of total production of African inland waters. Average productivity, it would seem, may be put at about 40 kg/y/ha of flooded area. It should also be noted that there is a close correlation between one year's catches and flood intensity of the previous year(s).
2.1.3 Fishermen
It is extremely difficult to draw a general picture of fishermen on floodplains, considering the great diversity of customs among the many ethnic groups of fishermen. For many of them, fishing is an occupation that has been traditional for many centuries; it often involves rites that are difficult to grasp. This greatly complicates the task of those who wish to guide fisheries along new paths. They must absolutely see to it that they do not too brutally jar their traditions. But they should be familiar with them! On the floodplains, fishermen migrate in accordance with the river's high tide and subsidence. Such migrations are about to disappear on numerous plains of Africa. They involve population movements from one country to another, and African governments discourage such nomadic fishermen who are difficult to control; all the more so as they take their catches with them and the authorities are increasingly aware of the potential wealth represented by the fishery resources of their waters. However, major migrations still take place within a country.
In general, floodplain fishermen are classified in three categories:
Occasional fishermen, i.e., farmers or stock raisers by vocation who practise subsistence fishing;
Seasonal fishermen, who combine farming with fishing and practise fairly intensive fishing during part of the year, which sometimes involves migration over small distances;
Professional fishermen, who fish throughout the year, depending on the level of the flood waters. They belong to highly specialized population groups and may undertake large-scale migrations leading them very far afield from their homes. The most typical groups fish the Niger River; they are mainly Bozos and Somonos of Mali origin and Haussas of Nigerian origin.
Conflicts occur between occasional and professional fishermen. The latter practise intensive fishing to meet short-term economic needs. Their migrations take them to areas traditionally occupied by occasional fishermen who struggle to ensure their long-term nutritional needs.
2.1.4 Techniques and Organization of Fisheries
Of all types of inland waters in Africa, it is doubtless on the floodplains and in the rivers running through them that fisheries are most ingenious and diverse as regards fishing gear, boats and strategy. This diversity results from the different kinds of fishing grounds (river at peak flood, as the waters subside, and at low water) as well as from the diversity in behaviour of a great many fish species.
Fishing gear can be of two kinds:
so-called “active” gear used for year-round fishing, but especially when the waters are low; fishermen operate the gear while fishing; it consists mainly of seines and castnets;
so-called “passive” gear, also used throughout the year but particularly wellsuited for fish populations in movement; this type of gear works all by itself and consists mainly of lines, gillnets, traps and pots, and barrages.
At the present time in Africa, new types of gear are coming into use and customary techniques are giving way to new ones. For instance, gillnets and castnets, which were virtually non-existent 20 years ago, have come into wide use. Generally speaking, the most widely used fishing gear today in floodplains are gillnets, seines, castnets and, to a lesser degree, lines and pots. The development of fishing techniques as far as gear is concerned is occurring at the expense of active gear that is impractical to handle and difficult of upkeep, such as the large “zemy” of the Logone-Chari (large triangular nets operated from pirogues).
In general, while the level of fishery technology is high in the best-known floodplains (Niger, Logono-Chari and Senegal), nets are sometimes inappropriate. They are supplied by traders who often exchange fish for what the fishermen needs (fishing material, food, cloth, sugar, etc.). This is why the material acquired by fishermen is not always suitable for the conditions of fisheries.
The organization of fisheries varies with water conditions: low water, floodwaters and subsiding waters.
(a) Low Water
At low water, fish come to be concentrated in the residual pools left on the plains and in the major bed of the river, so extremely intensive fishing can be done. During this period, the gear that contributes most to catches is definitely the so-called “active” gear (seines, castnets, pots and baskets handled by fishermen, liftnets), although so-called “passive” gear is also used to a large extent (gillnets, lines and pots). Of the latter, the gillnets, which are coming more and more into use, are the most efficient. This is by far the most productive part of the year for floodplain fisheries.
(b) Floodwaters
From the fishery standpoint, flooding is itself divided into two distinct periods: the initial tide before flooding and actual flooding of the plain.
- At the beginning of the tide, certain categories of fish move in great abundance in the river bed and are thus the appointed victims of passive gear (gillnets, pots, longlines with unbaited hooks, traps). Active fishing techniques are also used on a large scale during this period. The most remarkable illustration of the strategy of active fishing when the waters are rising is that based on controlled drifting of barrage nets or trolling along with the current, so to speak going to meet the migrating fish (for example: fishing of Tineni (Alestes leuciscus) in the Niger, combining the use of a barrage net drifting between two pirogues with fishermen using castnets downstream). Drifting gillnets are remarkably efficient during this period.
- During the peak flooding period corresponding to the time when the plains are inundated, the fish are dispersed over an enormous area. This corresponds to the period of least productive fishing which then most often becomes a subsistence occupation. The most widely used gear are lines, pots, gillnets and castnets. As a rule floodwater conditions are unfavourable for use of seines.
(c) Subsiding Waters
While the waters are receding, the fish resume migration toward the river, and this phenomenon leads to resumption of fishing. At that time, fishing is centred largely on young fish born in the flood area.
Pots and traps are the gear used to catch fish moving downstream. Small dams and drains can also be built by fishermen to facilitate the collection of juveniles (Oueme, Logone-Chari). During this period, fishing is often organized collectively, with distribution of the catch according to strict customary rules.
2.1.5 Fishing Boats
Fishing boats for floodplains come in a great many models. The most remarkable ones, owned by professional fishermen, are as a rule large, well-built and well-suited to river navigation. In areas where fishermen can readily obtain tree trunks, they are made of single tree trunks while in more desert regions (Niger) they are made of planks nailed together or else cut out of tree trunks with one or two sides built up of planks. Every-where pirogues are either rowed or pushed with poles. Outboard engines are used in some regions, for instance Niger, mainly to reach fishing grounds or markets quickly.
2.2.1 Definition, Description and Examples
What is referred to are well-defined watercourses, the flooding of which does not extend to large areas. Many rivers and streams fall into this category along certain parts of their course though they cross heavily flooded plains during high water downstream or upstream; for example, the middle reaches of the Black Volta, the Comoe, the Bandama and the lower reaches of the Congo.
Watercourses or parts thereof that fall into this category usually flow through rougher terrain than floodplain rivers, often in forest areas. They vary extremely in size, from the Lower Congo with its enormous discharge to forest streamlets found everywhere in the wet equatorial tropics.
2.2.2 Fishery Resources
Such rivers and streams yield much less fish in Africa than do the large floodplains, essentially because of the smallness of the production areas.
The fish populations here are also less fished because their density does not vary considerably over the year as happens in inundated areas (no great concentrations during the dry season). For this category of rivers and streams, the best fishing season is still the low-water season.
2.2.3 Fishermen
Fishing is mainly of the occasional or seasonal type, practised by the riverain populations. It should be noted, however, that in watercourses without floodplains in West Africa (Nigeria, Benin, Ghana and Ivory Coast) located close to the large fishing areas of the Sahel (Niger, Logono-Chari), one finds seasonal settlements of regular fishermen from Mali or Nigeria (Bozos, Haussas, etc.).
2.2.4 Techniques and Organizations of Fisheries
In this milieu, as a rule fishery technology is mediocre as compared with the major fishing zones on the floodplains. There is usually no brisk trade in fish, and a large part of production is consumed by the fishermen themselves. This tends to limit contacts between fishermen and merchants along the watercourses. Yet it is these very contacts which usually lead to better supplies of gear.
All the gear mentioned in discussing the floodplain areas is used for this type of watercourses (seines, gillnets, castnets, lines, traps, baskets), but generally less effectively. Passive fishing gear (pots, traps, barrages) is used most when the fish are migrating (high tide and when the waters recede), while active fishing techniques using seines, castnets or baskets are the ones that yield the major portion of the catch during times of low waters.
Involving relatively small total production, the organization of fisheries is less developed in this environment than it is on the large floodplains (Niger, Senegal, Logone-Chari).
2.2.5 Fishing Boats
Different types and sizes of pirogues made of single tree trunks are to be found on these watercourses. They are made locally and are more or less suited to the types of river or stream.
2.3.1 Definition, Description and Examples
Lagoons constitute an environment in between inland waters and sea waters. Lagoons, located in flat coastal areas, are fed fresh water from coastal rivers and sea water through channels. In some places, they can play an important role in the production of inland fisheries (Benin, Gabon, Ivory Coast, Madagascar, etc.)
2.3.2 Fishery Resources
Lagoon fish may be divided into two kinds:
Freshwater species, such as Tilapia, Heterotis, Clarias, etc., species that can thrive in water containing a certain degree of salinity; and
euryhaline species that migrate between sea waters and inland waters; this group comprises numerous species, the most typical one doubtless being the mullet.
Lagoons are distinguished from other inland waters by sometimes considerable shrimp resources. Shrimp are very much like euryhaline fish in their migrations and are a commodity of great commercial value. Shrimp reproduce in the sea and migrate between the lagoons and the sea, following a well known cycle. These migrations are taken advantage of to catch adults as the tides go out and the immature ones as the tides come in.
2.3.3 Fishermen
Lagoon fishing is practised usually by extremely dense populations of fishermen, sometimes they are even too numerous. These professional fishermen are often engaged in types of fishing that vary with the season.
2.3.4 Techniques and Organization of Fisheries
From the standpoint of artisanal fishery technology, lagoons resemble lakes (see paragraph 2.4), but differ as regards the techniques for catching migratory species (shrimp and euryhaline fish). These special techniques are based on the combined uses of barrages and traps (shrimp traps in the lagoons of Benin, mullet barrages in the lagoons of Madagascar). These sometimes elaborately designed structures and gear are made from traditional materials (laths and plant fibres).
Mention should also be made of a fishing technique peculiar to the lagoons of Benin, known by the name of “acadja” fishing. The acadja consists of a network of branches set out in shallow mud, with the purpose of getting the fish to concentrate in one place. Actual fishing consists in encircling the acadja with a net, removing the branches and catching the fish - a remarkably efficient technique.
2.3.5 Fishing Boats
The times of tiny mosquito-pirogues are past and in lagoons we find pirogues made of single tree trunks from the tropical or equatorial forest which is frequently nearby. These pirogues of massive wood are heavy, unstable and dangerous; long life would seem to be their only advantage.
2.4.1 Definition, Description and Examples
This category includes all natural lakes of Africa which are less than 30 m deep and do not form part of the lakes in the African Rift Valley. From a practical point of view, they are characterized by fisheries organized only on an artisanal scale. Lake Chad is the most representative example. Depending on the year, it covers an area of 5 000 to 10 000 km2 and has a considerable fishery potential. But Africa is dotted with very many large, small and medium-size lakes, the exploitation of which can have an important impact on the supplying of markets with fish. Some examples: the lakes of the Kagera basin, Lake George, the lakes of southern Malawi.
All these lakes are hydrologically more stable than the rivers and streams mentioned above. Some of them are subject to considerable seasonal variations (Lake Chad), but all of them normally offer year-round conditions suitable for fishing.
2.4.2 Fishery Resources
Whereas in regard to total inland fishery production of Africa the tonnage from such shallow lakes seems rather insignificant, the centralized production structure has an important advantage over other areas fished. The ratio between area (production potential) and shore length (fish landing facilities) is more favourable than it is along watercourses.
However, while lakes often permit centralization of production, which is good for the development of fisheries, they may be difficult to exploit appropriately in their entirety owing to the large distances that have to be covered under often precarious navigation conditions, which is a handicap to high fishery yield.
Natural productivity of tropical lakes varies in the extreme, ranging from 15 kg/ha in poor upland lakes to more than 100 kg/ha in fertile lakes of volcanic regions. Average productivity is about 50 kg/ha/y.
2.4.3 Fishermen
People living along the shores of natural lakes who practise fishing have as a rule been long settled there and fishing therefore is often done according to time-honoured custom. Among the populations, one encounters various attitudes toward fishing, from those of ethnic groups whose sole occupation it is to those who absolutely refuse to fish at all.
On Lake Chad, fishing conditions have radically changed owing to drought and the considerable drop of the water level in the past few years. Very dense vegetation has infested the lake along its shores, and the fishermen have organized themselves in line with the new ecological conditions. Three types of fishermen are to be found in this region:
Most fishermen live in permanent villages. Located far from the fishing grounds, they use big single-trunk pirogues with outboard engines. The product of their work provides them with a degree of prosperity. They are integrated into the commercial setup.
The second group lives in temporary camps on the lake shore or on islands. They move from one fishing place and sales outlet to another.
The third group lives in floating camps on ambatch rafts. As they cannot make major investments in gear and boats, they fish with traditional gear (longlines, pots) and move about in small single-trunk pirogues without engines.
2.4.4 Techniques and Organization of Fisheries
Fishery technology on lakes is often simpler and less diversified than on rivers because fish migration is rarely as great as in rivers and the milieu of lakes is more stable. The most widely used gear is the gillnet, but castnets, seines, lines and pots are also used.
The technological level of gear is mediocre owing to a lack of suitable supplies and organization of fisheries based on small units (two fishermen, one pirogue, a few dozen metres of netting). The gillnet most widely used nowadays is not really efficient unless there is sufficient drop and it is raised properly. All too often, for example, fishermen hang too much webbing on the ropes, which gives them longer mounted nets but of greatly diminished efficiency. Only rarely also do the small fishing units have several nets of a sufficient variety of mesh size. Mesh size is generally adjusted to the most common fish and the most usual size, leaving other fish species in the lakes underfished.
Other fishing gear suited to shallow lakes, such as longlines, castnets or fyke nets, are not used everywhere but could be easily brought into use. Original techniques for fishing, such as the “acadjas” in Benin, may also be useful when environmental conditions are favourable
2.4.5 Fishing Boats
In view of the long distances involved and navigation difficulties on lakes, the fishing boat plays a particularly important role. In contrast with what can be noted on certain watercourses with floodplains (Niger), boats on lakes are ill suited in many cases. They are too small, often equipped only with paddles, and cannot be used for fishing in bad weather. The best example of this aspect of artisanal fishing technology is certainly Lake Chad where fishermen traditionally used boats made from papyrus stems (there is no timber in the area) which were quite unsuitable for navigation on the large lake. At present, such kadayes have practically disappeared and have been replaced especially by small single-trunk pirogues strengthened with some planks. These pirogues are often equipped with a rudimentary sail which facilitates navigation on the lake. Nevertheless, this type of boat is dangerous and unsuitable.
2.5.1 Definition, Description and Examples
This category includes all small, medium-size and large man-made lakes. A distinction has to be made between large reservoirs (more than 1 000 km2) and smaller lakes found throughout Africa.
The large reservoirs (Lakes Nasser, Kariba, Volta, Kainji, Kossou, etc.) are intermediate as far as their size is concerned between the so-called “shallow lakes” described above and the big lakes of the African Rift Valley dealt with in the next section. As a rule, small-scale fishing is practised there, but very often it would be possible to develop more intensive fishing of pelagic species as well.
Small and medium-size reservoirs are fished in much the same way as shallow lakes. But all reservoirs differ from natural lakes due to their recent construction and their purposes (energy production, irrigation). These differences essentially affect the hydrological and chemical cycles of their waters, fish biology, and the social structures of fishermen populations.
2.5.2 Fishery Resources
It may be roughly estimated that the productivity of reservoirs is about 50 kg/ha/y, after reaching higher levels in the initial period after they have been filled with water. Small shallow reservoirs are perhaps slightly more productive.
Among the major reservoirs mentioned above (Nasser, Volta, Kariba, Kainji and Kossou), it would seem that only Lakes Volta, Kossou and Kainji are now being fished satisfactorily as regards productivity. Lake Nasser and especially Lake Kariba seem to be largely under-fished at present.
A multitude of small and medium-size reservoirs throughout Africa constitute a considerable production potential on the same footing as the large reservoirs, though they are often underfished. In a country like Upper Volta, where fish is in short supply, there are many such reservoirs, which makes their underexploitation all the more regrettable.
The basic fish population of reservoirs at the outset is made up of the species of the original watercourse. Passage from a running water environment to one of calm waters normally causes a profound change in the basic populations. Some species disappear entirely in the new environment while others remain or flourish in it.
In some cases, fish are introduced into reservoirs to fill certain unoccupied ecological niches. Usually this means introducing planktonophagous species not represented in the river fauna (in Lake Kossou, Tilapia nilotica and Heterotis niloticus; in Lake Kariba, sardinella to stock pelagic zones).
2.5.3 Fishermen
There are no customary fishermen on a recently built reservoir. Fishing is therefore done by local farmers who take up this new occupation or else by regular fishermen who come in from elsewhere. For riverain populations displaced by the reservoir, fishing is often an extremely attractive activity, sometimes enabling them to earn twice or three times what they could earn by farming. But the additional income is frequently wasted instead of being invested in fishing gear or boats. Any agricultural reconversion programme following the creation of a reservoir should provide for incentives to savings or investment of the profits from fishing.
A new reservoir often facilitates fishery development projects. The local population is not familiar with fishing and is more receptive to an artisanal technology that is appropriately geared to the milieu. This factor should be exploited to the maximum and the new fishermen populations should be provided with extension services from the moment when the reservoirs are filled with water.
All too often, unfortunately, the value of fishery production in reservoirs was not sufficiently taken into account when they were designed; even when a major fishery component was projected and studied, professional fishermen from other areas settle there, often to the detriment of the former local farmers who have taken up fishing. This happened on Lake Kossou which was invaded by Bozo fishermen from Mali, despite major programmes for fishery development. Great attention must therefore be paid to the human factors and proper training must be quickly provided for the local populations. Such migrations have been observed in the case of large reservoirs; by contrast, small and medium-size reservoirs are not invaded by foreign professional fishermen, but - and this is the other side of the picture - they are frequently underexploited.
2.5.4 Techniques and Organization of Fisheries
The first fishing gear to appear on reservoirs are gillnets; castnets, pots and lines follow. Because of the encumbrance of bush and forest vegetation, seines are only rarely used. To facilitate fishery organization on new man-made reservoirs, development work should precede their construction. Channels for fishing and navigation should be provided by felling trees; adequate fish landing or transport sites should be cleared of brush, and access roads or paths to the future reservoir should be built.
2.5.5 Fishing Boats
On new man-made lakes, fishermen often use single-trunk pirogues from the former water-course. They may be highly dangerous in squalls.
When a man-made reservoir is established, a programme often provides for the construction of suitable pirogues made from planks. They are made in small boatyards around the lakes by specially trained local craftsmen (e.g., on Lake Kossou).
2.6.1 Definition, Description and Examples
The deep lakes of Africa are mainly those of the Rift Valley (Lakes Malawi, Tanganyika, Kivu, Mobutu Sese Seko, Idi Amin Dada) and Lake Victoria. Their area ranges from 2 325 km2 (Lake Idi Amin Dada) to 68 635 km2 (Lake Victoria). They are veritable inland seas. Most of them have two distinct zones:
a biotic zone rich in plankton and fish, from the surface to a depth of 70 m (Lake Kivu) or 200 m (Lake Tanganyika); and
an abiotic zone, generally without oxygen and without fish, between the biotic zone and the lake bottom.
2.6.2 Fishery Resources
It is estimated that present production of Africa's deep lakes far exceeds 250 000 t a year. This could be increased substantially by a more rational exploitation of fish stocks1. For example, pelagic species are often underfished because they keep away from the shores. Yet they could be caught by relatively simple methods. For instance, according to recent estimates, Lake Kivu, which is virtually unexploited at present, could produce more than 30 000 t of small pelagic clupeids a year by artisanal night fishing using lights, liftnets and wooden or glassfibre catamarans. Even the lakes which are exploited have unfished areas containing interesting species, such as the northern part of Lake Malawi and some southern and central sectors of Lake Tanganyika. As a rule, a sustained fishing effort in these different types of deep lakes yields 20 to more than 100 kg of fish/ha/y. Compared with fisheries on seasonal floodplains, lake fisheries offer a stable source of protein throughout the year.
2.6.3 Fishermen
Three main groups of fishermen may be distinguished - occasional fishermen, artisanal fishermen and wage-earning fishermen.
More than half of the fishermen on the big lakes are local farmers who practise subsistence fishing close to shore. These occasional fishermen, who own their gear, sell only the surplus of their catch once they have met their own needs.
The artisanal fishermen live by the sale of their catch and devote only little time to their food crops. In general, they use fishing material that is more elaborate and more expensive than that of the occasional fishermen. They are not always the owners of their boats and gear.
Wage-earning fishermen work on a daily, weekly or monthly basis for boat owners, in small semi-industrial or industrial fishing units. In general, they are found near big agglomerations in relatively small number and live solely on their wages.
Artisanal and wage-earning fishermen often move along the shores, from one shore to the other or from one country to another in pirogues, depending on the fishing grounds and sales outlets.
2.6.4 Technology and Organization of Fisheries
There are four main types of fishing on the big lakes of Africa:
Customary fishing by day or at night near the shores using gillnets, pots, longlines, beach seines, handlines and spoon nets;
artisanal night fishing using fires or, more recently, petroleum pressure lamps and spoon nets, liftnets (square dipnets) or small purse seines;
semi-industrial fishing using mainly bottom pair trawls towed by motorized boats;
industrial fishing using seiners with surrounding nets of the ringnet type, with a net-carrying auxiliary boat and lamp-carrying boats or fairly powerful trawlers for catching pelagic or demersal species.
Most of the gear for these types of fishing is made locally from material manufactured by small local plants or imported.
Lake fishermen often specialize in a technique geared to the environment and fish stocks, employing relatively sophisticated material and tactics.
For fishing on an artisanal or semi-industrial scale, fishermen or owners in some countries may obtain government loans to buy their fishing gear and boats.
2.6.5 Fishing Boats
Most boats used by the fishermen of the big lakes are still dugouts; they are very unstable and therefore ill-suited to navigation on this sort of inland sea.
In view of the increase in timber prices owing to a shortage of big trees, this type of pirogue is gradually being replaced by small locally made boats of planks, which are more stable.
Metal catamarans are sometimes used in artisanal fishing with liftnets. Unfortunately, they are too heavy for easy handling with paddles or with a small outboard engine; they are therefore replaced by wooden or glassfibre units.
For semi-industrial and industrial fishing, some local boatyards make wooden or metal units that are well-suited to the various types of fishing.
Lastly, substantial savings in fuel could be achieved by the systematic use of sails as an auxiliary means of propulsion1.
