by
J.B.E. Awachie
Professor of Zoology
Chairman, National Advisory Committee on Fisheries Research
c/o Hydrobiology/Fisheries Research Unit
Department of Zoology
University of Nigeria
Nsukka, Nigeria
Abstract |
| The natural history and functional significance of river basin management in Africa is appraised in the light of current developmental characteristics vis-à-vis the traditional importance of fisheries to human sociological and economic welfare. Comparative models of on-going river basin development indicate massive disruption of natural production systems and environment with most negative impacts on the fishery and indigenous people on whom developments are imposed. |
| A discernible Africa-wide policy of using river basins as development modules to bridge the widening gap between rural and urban areas, thus stemming the drift of rural people to overcrowded cities, is examined, and attention is drawn to the need to develop policy guidelines for strategic planning development and management options, institutional arrangements, conservation as well as Africa-wide and international cooperation, in order to achieve desired goals. |
| An ecosystem approach to integrated basin management is indicated including detailed predevelopment studies and continuous monitoring undertaken to provide predictive capability for the abatement of stressed resources, for example, fisheries. In this connexion it is worthy of note that management results obtained through simulation models have shown that fisheries production can be optimized, in spite of the multiple and complex negative impacts within the multipurpose system of tropical river basins. |
Résumé |
| L'auteur retrace l'histoire et examine la signification fonctionnelle de l'aménagement des bassins hydrographiques en Afrique, en considérant les caractéristiques actuelles de leur aménagement à la lumière des activités de pêche qui y sont traditionnellement pratiquées et de leur importance économique et sociale pour l'homme. L'étude de divers projets en cours de mise en valeur de bassins hydrographiques, montre qu'il en résulte un bouleversement majeur des systèmes de production naturels et de l'environnement, avec des effets extrêmement négatifs sur la pêche et sur les populations locales. |
| L'auteur examine une politique qui se dessine à l'échelle de l'Afrique pour utiliser les bassins hydrographiques comme module de développement en vue de combler le fossé croissant entre zones rurales et zones urbaines et de freiner ainsi l'exode rural vers les cités surpeuplées, et il attire l'attention sur la nécessité de formuler des directives en ce qui concerne la stratégie à suivre, les options à retenir en matière d'aménagement, les structures institutionnelles, á mettre en place, la préservation de l'environnement et la coopération dans le cadre africain et international, si l'on veut atteindre les objectifs visés. |
| L'auteur expose une façon de concevoir l'aménagement intégré des bassins hydrographiques en partant de la notion d'écosystème et il souligne la nécessité d'exécuter des études détaillées avant la mise en valeur et d'exercer une surveillance continue pour établir des modèles prévisionnels qui permettront de ménager les ressources qui se trouvent dans une situation précaire. A ce propos, il convient de noter que les résultats obtenus à l'aide de modèles simulés montrent que la production de poisson peut être optimisée, malgré les effets négatifs nombreux et complexes de la mise en valeur des bassins hydrographiques tropicaux à des fins multiples. |
The concept of a river basin as unit or focus of human developmental activities is traceable to ancient times. In Africa, as elsewhere, it is probably as old as man himself. It derives from the fact that each river (or indeed, lake basin) provides man with easy access to the necessities of life-reliable sources of water and food, from both the aquatic and terrestrial systems. It is not surprising, therefore, that notable ancient civilizations were associated with the main inland water systems of Africa and, indeed as elsewhere in the world, for example, the Tigris and Euphrates, the Nile and the Niger, to name a few.
For the hinterland peoples of Africa, fish was and still is the most readily available source of cheap dietary animal protein. It is estimated that fish provides some 40 percent of all their human protein intake. This contribution tends to be higher among the rural riparian/lake basin peoples of the forest and wooded high savanna and decreases in the open and low savanna areas, especially among the cattle herdsmen.
The advent of western influence and the growth of big cities within the past 100 years largely disrupted the above set-up and witnessed a steady and ever-increasing drift of Africans to the cities with consequent lowering of the quality of life of the vast majority who provide unskilled labour.
The reactivation of river basins of Africa as modules for enhancing the rapid development of the rural economy with a view to stem the urban drift of rural populations, was initiated about three decades ago, by a few countries like Nigeria, Ghana and Egypt.
The idea of river basin development as an instrument or tool to integrate and restore equitable balance between rural and urban economic development is now generally accepted. Today, the establishment of river/lake basin development units as multipurpose use systems, has spread to practically all those African countries with large and permanent inland drainage systems (Figure 1).
This seminar, following almost two years after the “Expert Consultations on Fishery Management in Large Rivers” in Rome (Welcomme, 1979), and designed to focus on the topical issue of how productive fisheries can be managed in harmony with other activities in a multipurpose use system of river basin development, is considered timely. By pooling experience from various regions of Africa represented here, it should be possible to establish benchmark data for future management and development of river basins without jeopardizing their fishery which, as shown above, is very important to rural people. It should also provide the infrastructure, organizational and cooperative framework for the formulation of reliable Africawide predictive models to minimize the negative impacts on fisheries production by other competing basin activities, e.g., hydroelectricity, irrigation, flood control, navigation, etc. The overall policy and strategy for the achievement of the above are to be indicated (Awachie, 1980).
The major inland fisheries of Africa are supported by the major inland drainage systems which exhibit seasonal cycles in their water levels (Figure 1). The river channel and the seasonally inundated floodplain with its often numerous permanent and temporary lakes, lagoons, ponds and swamps provide the environment for rich fisheries and agricultural production which characterizes the system in the normal unaltered condition.
The nutrient and energy cycles which provide the basis for productive activities on the floodplain are summarized in Figure 2. Welcomme and Hagborg (1976) by simulation techniques developed a general model which describes the way in which the fish populations of African rivers and their fisheries are influenced by different types of flood regime (Figure 3). The value of such a model in enhancing predictive capabilities of fishing managers and consequently the development of appropriate management techniques for various fisheries within the system, has been demonstrated by Welcomme and Henderson (1976) and Welcomme (1979) (Figures 4 and 5). The point being emphasized here is that even in the natural multiple use system of an unmodified river basin, identification of the main factors of production and their relationships will facilitate management actions aimed at increasing production.
It would seem appropriate, at this juncture, to draw attention, even if in outline only, to the biological and human activities resulting from the foregoing abiotic energy and nutrien dynamics in an unaltered floodriver system. As summarized in Figure 6, the abiotic component flow conditions - controls productivity cycles in both terrestrial and aquatic environments and hence intense human economic and sociocultural activities in terms of fishing, crop and animal husbandry, and associated festivals. The latter occur in rotational sequence with the flood phase representing the peak of fishing activities, which the dry phase is more important for field agricultural production.
The above represents the classic picture of the traditional floodplain within which activity rhythms of all organisms including man and his institutions are adapted to the innately unstable flood cycle. It also depicts a level of evolution and development in which floodplain resources are exploited most intensively but in an integrated way.
Within the last two decades in Africa, socio-economic pressures consequent on the ever-increasing human population, the need for land, water and electric power for agricultural, municipal and industrial developments, inter alia, have led to widespread flood control measures with concomitant disruption of floodplain biocoenoses, rhythms of activity and, above all, production (Figure 7).
Most adversely affected is the fishery, its productivity and management, which therefore must be re-appraised and redeveloped and managed to an optimal level within the changed system. This is so because as pointed by many authors (United Nations, 1970; White, 1973; Welcomme, 1976; Awachie, 1975, inter alia), only in rare cases are the interests of living aquatic resources taken into consideration in planning major alterations of the floodplain. In some cases, this may have been due to the fact that adequate data were unavailable at the planning stage.
Consequent on the foregoing, the following features are currently characteristic of African river basin management and development:
Large dams for hydropower and water resource management;
Unmitigated negative impacts of the large dam approach to development, especially as they affect fisheries, as found in the Kainji (Nigeria), Volta (Ghana) and Kariba (Zambia/Zimbabwe) Dams. The indications are that many of the new or projected dams, e.g., on the Senegal River (Mali) (Smith, 1968) will have similar effects;
National policies which favour the urban consumer. Lipton (1977) and Scudder (1978) have observed that this bias is particularly blantant in tropical Africa, in spite of the fact that rural populations comprise 60–90 percent of the total in these countries. In connexion with the large dams, for example, it is noteworthy that, with the possible exception of Kossou (Ivory Coast), no significant rural electrification scheme is associated with any existing or planned dam projects. This situation helps to provide renewed impetus for the migration of rural peoples to urban centres;
Imposition of development plans by governments. Scudder (op. cit.) has rightly described river basin development in Africa as a classic example of “the development from the above syndrome”. Local populations who bear heavy social costs of the developments including loss of homes, fertile farm lands and fishing grounds, are not usually consulted in any of the critical decision-making phases of project planning, implementation, management and evaluation, and
Establishment or creation of a new system. The system is derived from the modified river basin and is more or less unstable. It is typified by such major landscape features as man-made lakes, polders, dykes, etc., each of which has its own characteristic subsystems with the main components being ecological, production, socio-cultural and economic systems. The functional relationships between the components of a man-made lake ecosystem, e.g., Kainji Lake, are illustrated in Figure 8.
It is now fairly well established that the impact of a man-made lake in the morphology, terrestrial and aquatic resources of a river basin will vary in the three main regions of the modified system viz., upstream areas above the lake, the lake area, and areas downstream of the lake. The lake region and downstream areas are most negatively impacted with fish and fisheries being very adversely affected, e.g., longitudinal and lateral breeding migrations of anadromous species are exterminated by new lake conditions, while downstream, the desiccation of the floodplain reduces the wet lands and isolates floodplain lakes, ponds, etc. (see Figure 7) which not only serve as nursery grounds during the flood phase, but provide a rich pool fishery during the dry season/low water phase.
The above outline characterization of current features and trends in river basin development in Africa is considered sufficient to indicate that a radical change is required in the policy objectives governing their development. Politics of planning and siting of projects should be re-examined as well as developmental and management approaches to be employed, taking full cognizance of relevant and contending economic, sociological and sociocultural parameters. This would ensure inbuilt abatement measures of the above parameters that are negatively impacted. Comparative studies of river basin development and management in Africa indicate that the rural people who have to be relocated and the fishery receive the harshest negative impacts (Harding, 1966; Jackson, 1966; Visser, 1970; Obeng, 1969; Stanley and Alpers, 1975; Scudder, 1966, 1978, inter alia).
It is suggested therefore that policies for future river basin management and development should aim at the following:
Integrated rural and urban development. Provision should be made for the setting up of agro-based industries, e.g., food processing plants within river basin areas; rural electrification and housing projects should be embarked upon to improve the quality of life of river basin peoples;
Full consultation and involvement of local people from the planning to implementation stages in the development and management of river basins, and
Integrated management of the “total environment” of the river basin in order to optimize production from all sectors.
Based on the above policy framework, it should be possible to map out detailed procedures aimed at achieving policy objectives. These should include the following:
Various developmental options should be considered, and based on African experience so far. A systems approach is indicated. This will ensure basin-wide perspectives to development and management, thus allowing for desirable adjustment or abatement for those parameters which receive negative impacts during the process of development. It will, above all, make for social equity.
It is necessary from the inception of the project idea to develop strategic plans in order to: (a) establish programme direction; (b) define targets of production for specified periods, against which progress and achievement can be measured; (c) outline strategies which will be followed to achieve the targets or objectives, and (d) outline resources which will be needed in order to meet objectives. At this stage, clear appreciation of the social aims of development is necessary to provide a basis for choosing among alternatives. An appraisal of accumulated pre-development data, including those from feasibility studies on the physical-chemical, biological and human features of the basin is critical in adopting and developing the right plans.
Based on the experience of the last two decades, the multipurpose use concept in river basin development seems to provide the most equitable option on which basin-wide plans may be based.
If the multipurpose use system is accepted as the centre piece for balanced development of a river basin, then the obvious management procedure is one which is in sympathy with policy objectives on this consideration, i.e., integrated management of terrestrial and aquatic production systems. It should be possible to develop systems in which all the living resources are managed together. Thus a system which links the management of fisheries, forestry and agriculture to those of agro-industrial and hydroelectric units will facilitate recycling of nutrients, optimize the production of the river basin, minimize pollution, eutrophication, biocides and toxic substances and health hazards consequent on changes in the hydrobiological and socio-cultural milieu, e.g., bilharziasis, malaria and other aquatic hosts and vectors of diseases.
Fishery management is treated here as a special case within the context of river basin management and development, because on the one hand fish are very sensitive to alterations in the hydrologic regime and secondly, in practically all known basin developments in Africa, fisheries have received little or no consideration in planning and executing water and land resources development. Consequently there have been severe negative impacts. This often results in the rapid decline of fisheries production, both qualitatively and quantitatively but, above all, in the local disappearance of various aquatic species, thus threatening the integrity of the ecosystem. This situation continues to repeat itself in spite of the fact that fish, as pointed out above, is a major source of animal protein to most hinterland people.
In developing and executing of strategic plans in the river basins of Africa, therefore adequate inbuilt safeguards should be provided and suitable and/or compensatory management techniques employed to sustain recruitment cycles in the altered condition, thus maintaining a desired level of fish production.
Compensatory techniques include the provision of channels, fish ladders or lifts, as appropriate, to facilitate breeding movements of fish; strategically timed release of reservoir water and/or canalization of the latter to desiccated downstream floodplain wetlands, ponds and lakes, and the location of hatcheries at strategic points in the basin to provide desired fish seed with which to stock isolated basin lentic waters, as well as adversely affected stretches of the river channel. The role of aquaculture as an applied management measure in maintaining fisheries production in river and lake basins has been emphasized by Awachie (1975, 1976, 1980).
In the altered river basin, management surveys would have to be undertaken in all fishable waters - reservoirs, natural lakes, upstream and downstream sections of the main water control developments - to determine which of the management tools or combinations of them, viz., maximum sustainable yield (MSY), optimum sustainable yield (OSY), maximum economic efficiency (MEE) or total sustainable biomass (TSB) of Wallace (1975), will provide the best fish landings or combinations of socio-economic and nutritional benefits for the indigenous basin people who are usually the most adversely affected by basin developments.
It is further emphasized that because fishery problems in a multiple use system are varied and complex, capability to predict possible fishery impacts of planned river basin uses would facilitate the maximization of benefits derived from all contemplated uses; otherwise, as Pantulu (1978) pointed out, the very benefits to be derived from a given use can be negated by resultant losses in fisheries. These can be considerable. For instance, Pantulu (op. cit.) noted that in the Mekong Basin, where a fairly comprehensive study of the possible effects of integrated development of the river basin on the fisheries was conducted, it was estimated that in an 85-km stretch of the river alone, fishery losses would be about 2 000 t of annual catch with a market value of US$ 1.05 million. The need to undertake such studies to provide comprehensive evaluation of fishery problems in multiple use systems, on an Africa-wide basis is underlined, as it will lead to a desirable and early establishment of a basic African model for fisheries management within a multiple use system of river basin resources.
As part of an emerging overall strategy to use river basins as an instrument to achieve balanced and integrated human and economic development in continental Africa, it is important to develop an adequate and effective institutional framework to manage and develop river basin resources, for, as Johnson (1980) has pointed out, continued wealth and well-being of the society is dependent on successful development, management and protection of these resources, viz., land, air, water and fisheries.
Considering the present level of development and availability of relevant scientific, technological and managerial manpower in most African countries, and in order to benefit from accessible international expertise, it would seem necessary to have institutions organized on a two-tier or three-tier basis.
Comprising: (a) national executing agency comprising administrators, production and research scientists and technologists, including extension and technology transfer personnel and a training wing, and (b) cooperating international experts from such bodies as UNDP, etc.
Comprising: (a) national agency comprising administrators, production scientists of various types, technologists and relevant service support units; (b) specialized and multidisciplinary research institutes to provide research and development services to the various river basin agencies to satisfy their needs for basic information to ensure maximum production and rational development, and (c) a unit of international experts to provide specialized services in production, development, appraisal and training.
The type and details of institutional organization in various African countries, as elsewhere, will relate to the prevailing political and socio-economic climate as well as to the leadership quality available at any point in time.
By way of illustration, the structure and organization for river basin management and development in Nigeria may be outlined here. In order to achieve even development, Nigeria has, within the last 15 years, created 19 municipal states in the Federation.
To take development to the grass roots and ensure equity and social justice in the development of urban and rural areas, the country is currently organized into 11 Federal River/Lake Basin Development Authorities (RBDAs) (Figure 9), most of which, as may be expected, cut across state boundaries, viz.: (1) Sokoto-Rima Basin (with Sokoto as Headquarters); (2) Hadejia-Jema'are Basin (Kano); (3) Lake Chad Basin (Maiduguri); (4) Upper Benue Basin (Yola); (5) Lower Benue Basin (Makurdi); (6) Cross River Basin (Calabar); (7) Anambra-Imo Basin (Owerri); (8) Niger Basin (Ilorin); (9) Niger Delta Basin (Port Harcourt); (10) Benin-Owena Basin (Benin City), and (11) Oshun-Ogun Basin (Abeokuta).
This structural organization conforms to the three-tier system. Each basin is managed by a River Basin Development Authority (RBDA) with a Board of Management and a General Manager superintending a spectrum of scientific, managerial and technological/professional personnel responsible for the execution and monitoring of developmental production processes in the basin. Each RBDA is responsible to the Federal Government through the Ministry of Water Resources.
Research input on basin resources management and development is provided by relevant specialized or multidisciplinary research institutes. There are at present 23 of these, strategically located all over the country. Thus, while the Nigerian Institute for Oil Palm Research (NAIFOR) has its Headquarters in the palm belt city of Benin, the Cocoa Research Institute (CRIN) at Ibadan in the heart of cocoa producing area, and the Leather Research Institute is based in the savanna city of Kano while the multidisciplinary Lake Chad Ŕesearch Institute is located in the Chad basin town of Maiduguri. Each research institute, like RBDA has a Board of Governors which is responsible to the Federal Government through the Ministry of Science and Technology. All of the research institutes are under the Federal Ministry of Science and Technology.
Associated with relevant research institute(s) or RBDA within a basin area are independent units of national or international cooperating agencies which are assigned to specific projects of research, management development studies, production processes, socio-economic appraisals, etc., on a consultancy or bilateral basis. Their functional relationships are summarized in Figure 10.
It is hope that as the basic structure and mode of development and management of other river basins become available from other countries in the region, a common denominator or an African approach/model may emerge and/or be formulated. To achieve this, critical comparative assessment of alternatives in river basin development in relation to social or socio-economic goals, as well as impacts of the various alternatives, would be required.
Practically all the major rivers of Africa, e.g., the Nile, Niger, Senegal, Volta, Zaire, Zambezi, etc., flow through a number of riparian states with consequent legal, political and complex socio-economic implications for their management and development (Austin, 1968; Watt, 1968; Jones, 1968). This is particularly so in case of water resources developments by upstream states which will alter the flow characteristics of the river downstream with consequent severe negative impacts on biological, fisheries and human production systems, especially fisheries.
The achievement of social justice and equity in river basin developments along such rivers calls for the highest level of cooperation, informed and far-sighted political leadership among affected riparian states, the establishment of policies, overall strategies and management approaches, and institutions to superintend and coordinate developments. If African states involved accept the ‘best-use’ principle defined as the maximization of socio-economic returns subject to both biological and economic constraints (Mitchell, 1980), then the adoption of the ecosystems approach, as well as associated policies and strategies to achieve desired objectives, as outlined above, would be recommended.
On institutional arrangements, it is to be observed that basin-wide commissions or joint commissions for coordinating water resources development along international rivers/lakes in Africa are not wanting. Even though some of these were created by cooperative instruments negotiated by African countries themselves, and others with the aid of foreign and/or international organizations such as FAO/UN, their effectiveness in moderating and coordinating basin-wide developments, is yet to be appreciated. Major impediments in the way of joint or international commissions include the polarization of national jurisdictions, bureaucratic approaches, and difficulties in reconciling national developmental priorities with societal goals of cooperating countries.
A possible method to ensure ordered and optimal use of international river basin resources would be to set up regional inter-African or international working parties on a few selected rivers. This would enhance the development of an acceptable African approach to the above problem. This is particularly important for the survival of both artisanal and commercial fisheries in downstream states.
It would be the function of each working party to establish the appropriate organizational structure required to carry out the development of appropriate analytical models and to integrate them with the existing planning frameworks. Eventually, this will culminate in the establishment of “regional institutes for river basin management and development research”.
Specifically, the regional institutes will experimentally develop acceptable approaches to the improvement of river basin development planning and provide guidance to existing national research units as well as other national and inter-governmental planning agencies. In addition, the regional institutes will be charged with the responsiblity to undertake evaluation and long-term monitoring of pilot and experimental programmes indicated above.
Recent developments in the Lower Mekong Basin in Southeast Asia, comprising Democratic Kampuchea, Lao, Thailand and Viet Nam, have shown that optimization of fisheries production within an integrated multiple use river basin development, is possible provided basin-wide comprehensive studies are undertaken to establish the possible effects/relationships of all planned uses of the river on the fishery. Such a study was accomplished with the cooperation of the riparian states indicated above (Committee for Coordination of Investigations of the Lower Mekong Basin, 1976).
As in many African areas, fish and fishery products provide about 50 percent of the animal protein intake of local people. Because of the vital role of fish in both the diet and production system of the Lower Mekong people (some 25 percent of the 35 million inhabitants are in the fisheries business), basin pre-modification studies were carried out to identify, predict the direction (positive or negative), extents and values of these impacts on both capture and culture fisheries.
With the information gathered, about six proposed major groups of basin-wide activities which impact on fisheries (dam construction and emplacements, agricultural development, industrial development, flood control, navigation improvement and freshwater fishery development) and their interrelationships within the system of integrated development of the basin, predictive models were developed. These facilitated the adoption of suitable management measures, including abatement procedures, to achieve the optimization of fisheries production in the modified Lower Mekong valley. An abbreviated type of such models, which shows the systems of complex interrelationships that influence fish catch is illustrated in Figure 11.
For instance, although it was shown that “basin-wide development following the Indicative Plan could result in an overall loss in annual total fishery catch within the basin of between 32 447 t and 48 207 t with a landed value of about US$ 5–6 million”, it was found that effective fishery management could increase the yield so significantly that the possible losses would not occur. Attention may also be drawn to the fact that the above achievement did not include the dramatic potential benefits of aquaculture in the basin.
The above picture of the Mekong contrasts sharply with that of Nigerian/Niger development in Kainji where the sensitivity of fisheries to the major alteration of the water flow regime, caused by the Kainji dam, led to significant depression of fisheries production in all affected areas from the lake to the apex of the Lower Niger delta (Awachie, 1978). Indeed, the pre-impoundment studies in Kainji, as elsewhere in Africa, were no more than salvage operations. They were of short duration (White, 1965) and not sufficiently detailed and basin-wide as to be useful for meaningful prediction of the fate of the fishery.
The above situation would appear to have occurred in most of the major river basin developments in Africa and appears to persist because the grim fact is that the dynamics of biological production in tropical Africa are still not well understood. As a result, fishery management in most African river basins continues to be empirical.
It has been noted aboved that as a matter of deliberate policy, the river basins of Africa are closely associated with the current rapid rate of economic development in Africa. Negative impacts of integrated basin development on the environment could be severe and might lead to a complete and unnecessary change of the ecology of the target area for development. It is therefore considered essential that conservation measures be inscribed in the policies governing the management and development of river basins in African countries.
More often than not, river basin development is associated with gross ecosystems disruption and consequent deterioration of environmental quality. Dealing with this problem in relation with fisheries management of the Great Lakes of North America, Johnson (1980) has emphasized that the continued wealth and well-being of society depend on successful development, management and protection of the resources - land, air, water and fisheries. Complex interplay between air, water and water communities is better appreciated through the misfortunes of serious environmental issues such as pollution of air by massive emissions of sulphur and nitrogen oxides leading to acid rains with adverse impacts on fisheries and aquatic resources, e.g., sensitive lakes and streams, etc.
In tropical Africa, massive deforestation in river basin development areas to provide firewood, land for field crops, animal husbandry, housing projects and lumber and agro-based industries lead to rapid deterioration of forest soils, desertification, and an intractable erosion menace with its concomitant sediment load problems and adverse impact on fisheries production/fish species composition. In this connexion, observations recently made in “Global 2000 Report to the President” of the United States and issued on 24 July 1980, on the global environmental situation and tropical forest ecosystems, would seem relevant.
The picture is that “if the present trends continue, the world in 2000 will be more crowded, more polluted, less stable ecologically and more vulnerable than the world we live in now”. The report makes special reference to the need for a strategy to conserve the world's tropical forests by promoting the wise use of tropical forests through American foreign assistance, educational programmes of international institutions, e.g., FAO of the United Nations, and new initiatives in research and technology which can reduce pressures for exploitation of tropical forests.
It suffices to re-emphasize here, that if the ‘ecosystems approach’ advocated above is applied to conservation problems arising from river basin management and development in Africa and, indeed, elsewhere in the so-called developing countries, then fishery and environmental quality issues will be tackled at the grass roots in a broader, less compartmentalized manner, thus providing comprehensive approaches to their solution - be the problems those of pollution, eutrophication, waste management, biocides, environmental toxicology or even those of diseases attendant on environmental alteration.
In this address, the history of river basin management and development in Africa have been outlined especially as they affect the fishery. It is fairly well established that fishery resources are very sensitive to modifications of the environment arising from basinwide management. Impacts on fisheries from other basin development activities are often significant and may be quite severe as in the case of the single purpose dam developments which characterize existing river basin developments in Africa.
Fishery problems are shown to be quite varied and complex within multipurpose use river basin development, because all the planned development activities will impact upon the fisheries, both natural (capture) and aquaculture. There is therefore need to undertake, prior to the initiation of basin development, detailed multidisciplinary studies to provide a data base for planning basin-wide management and development. In the case of fisheries, such data will provide predictive capability for management thus optimizing fisheries production.
For river basin development in Africa in the future, efforts should be made to develop a common African approach within clearly defined and agreed policy guidelines, even though emphasis and developmental priorities/alternatives may differ. To optimize benefits from all sections and safeguard environmental integrity, an ecosystems approach to integrated multiple use systems is indicated.
Adequate strategic planning and development of management options for fisheries and other resources to be developed, will require the availability of expert manpower in all disciplines to be involved at all stages of river basin resources development. At the present level of technical and managerial competence in the region, inter-African and international cooperation would be necessary to assemble required staff and develop national and regional institutions for development.
Functions of the “Regional or Africa-wide Institute(s) for River Basin Development Studies” should include:
Comparative studies on river basin management;
Establishment of an “Information Base and Documentation Centre”;
Development of African models for the optimization of integrated management of river basin projects;
Provision of continuous monitoring and case assessment for environmental, economic and human parameters of the river basins, and
Advising national RBDAs and research institutes on matters relevant to their national assignments.
It is hoped that the invited contributions and experience papers from various CIFA countries will provide fresh and various new dimensions to the many issues in river basin development and management in Africa, which for lack of space and time have barely received mention in this address.
Figure 1 Major river basins of Africa with their floodplains: (1) Senegal; (2) Niger-middle delta complex; (3) Oeme; (4) Niger-Anambra; (5) Benue. (6) Chari and Logone systems including the Yaeres; (7) Nile Sudd; (8) Zaire, Ubangui and Sangha floodplain complex; (9) Luapula-Mweru system; (10) Zambezi-Barotse plains; (11) Zambezi-Kajue plains; (12) Shire-Elephant and Ndinde marshes; (13) Okovango-Lake Ngami system; (14) Limpopo
Figure 2 Energy and nutrient dynamics on a natural floodriver basin (adapted from Welcomme and Hagborg, 1976)
Figure 3 Model of normal relationships in the dynamics of African floodplain fish and its fishery (adapted from Welcomme and Hagborg, 1976)
Figure 4 Theoretical parametric changes in a multi-species fishery with fishing pressure (from Welcomme and Henderson, 1976)
Figure 5 Numerical dynamics of fish in one age group over 52 weeks. Simulated water levels indicated (from Welcomme, 1979)
Figure 6 Seasonal relationships between environmental dynamics and human activity cycles in the flood river basin (adapted from Welcomme, 1979)
Figure 7 Desiccated downstream floodplains by Kainji Dam - Tada area, Nigeria
Figure 8 Summary of the relationships of the components in a man-made lake ecosystem (from ICSU, 1972)
Figure 9 River systems of Nigeria and their organization into 11 River Basin Development Authorities (RBDAs): (1) Sokoto-Rima Basin; (2) Hadejia-Jema' are Basin; (3) Lake Chad Basin; (4) Upper Benue Basin; (5) Lower Benue Basin; (6) Cross River Basin; (7) Anambra-Imo Basin; (8) Niger Basin; (9) Niger Delta Basin; (10) Benin-Owena Basin; (11) Ogun-Oshun Basin
Figure 10 Structural and functional relationships of River Basin Management and Development Agencies in Nigeria
Figure 11 Model of system of interrelationships which influence catch. (Adapted from “Report of the Mekong Basin-Wide Fisheries Studies, 1976”)
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by
Mac Litterick
Department of Zoology
University of Nairobi
P.O. Box 30197
Nairobi, Kenya
Abstract |
| Kenya is a country with a relatively small quantity of major inland drainage systems. Permanent rivers total less than 4 000 km in length; however, limited water surface and a high population growth rate put a premium on proper management and development of river basins. |
| Examples are given of management and development in two contrasting drainage basins in Kenya, the Tana River Basin and the Lake Victoria Basin and the impacts of these developments on fisheries. It is concluded that while the nature of negative impacts on fisheries are well known as are the solutions to the problem, persistence and recurrence of these problems is in the practical difficulties of implementing solutions. Management of river basins in Kenya will remain geared mainly to water supply needs with fisheries of lesser interest. Fisheries will indirectly benefit, however, because of the need to maintain good water quality for supply purposes. The good quality water thus available can be turned to advantage both for maintaining capture fisheries and for use in fish culture. |
Résumé |
| Le Kenya compte relativement peu de grands réseaux hydrographiques. Avec des cours d'eau permanents d'une longueur de moins de 4 000 km au total, il est d'autant plus important, compte tenu du taux de croissance démographique élevé, d'aménager et de mettre en valeur le mieux possible les bassins hydrographiques existants. |
| Ce document étudie, à titre d'exemple l'aménagement et la mise en valeur de deux bassins hydrographiques très différents, celui du fleuve Tana et celui du lac Victoria, et les répercussions de cet aménagement sur les pêcheries. L'auteur conclut que les effets négatifs sur la pêche sont bien connus, de même que les solutions à apporter à ces problèmes, mais que ceux-ci persistent néanmoins et réapparaissent en raison des difficultés pratiques d'application des solutions envisagées. L'aménagement des bassins hydrographiques du Kenya continuera à être axé sur l'approvisionnement en eau, les intérêts de la pêche demeurant au second plan. Toutefois, la pêche bénéficiera indirectement de la nécessité de maintenir la qualité de l'eau à un niveau satisfaisant pour l'approvisionnement de la population. La lutte contre la pollution de l'eau peut ainsi s'avérer bénéfique tant pour la pêche que pour la pisciculture |
The surface water resources of a region are the result of the interaction between the physical relief and climate of the region. Past geological events create catchments and lake basins while differences in altitude influence rainfall and temperature. The turbulent geological history of East Africa associated with the formation of the East African Rift Valley system has produced in Kenya a country of marked physical contrasts, experiencing a wide range of climatic conditions.
Rainfall in Kenya is characteristically low and erratic with an uneven geographical and temporal distribution. Over 70 percent of the country receives less than 500 mm of rain per annum; 13 percent between 500 and 750 mm, and only 15 percent receives more than 750 mm (Kenya, 1972). This low rainfall (annual mean 500 mm) coupled with high rates of evaporation and seepage into groundwater reservoirs, reduces significantly the water available for run-off to less than 5 percent of precipitation with a range from 1 to 12 percent in the Rift Valley Basin and the Lake Victoria Basin, respectively (Table 1).
Kenya is thus a country not endowed with major inland drainage systems and possesses less than 4 000 km of permanent rivers, most of which are small by African standards. The annual discharge from all Kenyan rivers amounts to approximately 14 × 109 m3; this can be compared with discharges from several major African rivers, for example, Zaire (1 293), Zambezi (220), Niger (189), and Nile (94) × 109 m3 yr-1.
Table 1
The catchment area, mean annual rainfall and mean annual run-off of the drainage basins of Kenya
| Drainage basin | Catchment area '000 km2 (%) | Mean annual rainfall (mm) | Mean annual run-off 106 m3 (%) | Run-off as percent of rainfall | |||
| I | Lake Victoria | 45 | (8.4) | 1 245 | 6 705 | (46.9) | 12 |
| II | Rift Valley | 127 | (21.8) | 535 | 860 | (6.0) | 1 |
| III | Athi River | 70 | (12.0) | 585 | 1 294 | (9.0) | 3 |
| IV | Tana River | 132 | (22.7) | 535 | 4 700 | (32.9) | 7 |
| V | Ewaso Ngiro | 205 | (35.1) | 255 | 740 | (5.2) | 2 |
| Total Mean | 579 | 631 | 14 299 | 5 | |||
Source: Kenya, 1972; Ongweny, 1979; Ongweny (undated)
The resultant limited surface water resources in conjunction with the highest population growth rate in the world (4.04 percent) (Myers, 1980) puts at a premium the proper management and development of drainage basins for domestic, agricultural and industrial water supply. The development and management of river basins is therefore principally directed toward enhancing the availability of water for supply. Fisheries are generally treated as incidental though not altogether ignored. In addition, the importance of fish in the Kenyan diet is localized and consequently inland fisheries, and river fisheries in particular, receive a low priority at the national level.
River basin developments in Kenya, as elsewhere, are essentially of two distinct types. First, direct developments which modify the rivers themselves and principally involve impoundment, but in more limited circumstances include river diversions, canalization, and interbasin water transfers. Second, land utilization development of the catchment area of a river which inevitably has indirect but equally important effects upon the river and its fishery.
The effects of development, either of the direct or indirect type, can be broadly categorized as follows:
The alteration or destruction of riverine habitats; of especial importance are changes to those areas used by fish for spawning purposes.
Denial or restriction of access to suitable habitats; again spawning sites are of importance particularly in anadromous species. Restrictions may be imposed physically, for example, by the construction of dams not provided with fish passes, ladders or lifts. Similarly the regulation of flood water may deny access to floodplain lakes and pools for riverine lateral migrants. Access may also be limited by chemical barriers in the form of water pollutants entering the river in the effluent discharges of bankside industries, irrigation schemes or settlements.
Reduction in flood discharge which results in a reduced stimulus to migrate; this is naturally a significant factor controlling anadromous species whether migrating into rivers from the sea or from lakes.
The present drainage system in Kenya is the result of past and recent tectonic and volcanic events associated with the formation of the Rift Valley and comprises five distinct drainage areas (Kenya, 1972). These areas are delimited in Figure 1, and pertinent data relating to them are summarized in Table 1.
The Lake Victoria Basin (LVB) and the Tana River Basin (TRB) occupy a little over 30 percent of the land area of Kenya, but together contribute nearly 80 percent of the countries annual run-off. They also contain, along with the Athi River Basin (ARB) the majority of the Kenyan population (Kenya, 1972). The LVB and TRB are both managed by development authorities, namely the Lake Victoria Basin Development Authority, set up in 1978, and the Tana River Development Authority which was formally established in 1974, and which since 1979 has had control also over the Athi River Basin. The LVB and TRB together provide adequate examples of basin development and management in Kenya and the consequent impact on fisheries, and therefore only these two basins will be considered further.
In terms of their development and the ecology of their river fisheries, the Victoria and Tana basins are in marked contrast. The LVB is a multi-river basin containing approximately 10 rivers of significant size which drain about 47 percent of Kenya's run-off westward into Lake Victoria. The TRB is, on the other hand, a single basin containing the Tana River and its several tributaries which drain 33 percent of Kenya's water eastward into the Indian Ocean.
Figure 1 The major drainage basins and principal centres of population in Kenya
Development in the Victoria basin is predominantly of the indirect ‘catchment’ type which is leading to rising levels of pollution in the Nyanza rivers and the lake. Effluent is contributed mainly by agriculture-associated industries including that from the many sugar refineries which are located on several of the larger rivers, for example, the Nyando, Kuja, and the Nzoia. Also on the Nzoia is sited the Pan African Paper Mill, which appears to control its effluent to a particularly high standard (pers.comm., B. Meadows). The increasing quantities of effluent discharged into the upper Nzoia from the rapidly expanding industries in Eldoret are sources of potentially serious pollution, if proper and effective means of control are not implemented and enforced.
Several operational irrigation schemes abstract water from the rivers in the LVB and proposed expansion of these and additional schemes with hydroelectric generation, are either under consideration or construction (Ongweny, 1979). These direct developments, if undertaken, will have unpredictable effects on river fisheries, but will hopefully allow for the extension of dam and pond fish culture. Increasing levels of siltation in these rivers is, however, causing concern and delays in the implementation of some planned developments (Ongweny, unpublished).
The Tana River Basin is characterized by major direct development of the river. The Tana is at present dammed at three sites, Kindaruma, G'taru and Kamburu, for the purpose of hydroelectric power generation with ancillary provision for irrigation. A fourth dam, the Upper Reservoir at Masinga is due for completion in early 1981 and will provide seven months live storage to increase the generating capacity of the lower dams and to further develop the irrigation potential within the upper and lower Tana basins. It will simultaneously provide additional water for supply to Nairobi.
The headwaters of the Tana and its tributaries drain the steep slopes of the Aberdare Range and Mount Kenya where forest clearance and inadequate attention to soil conservation are contributing massive quantities of sediment to the rivers (Ongweny, 1976). Soil erosion constitutes the major environmental problem in Kenya today and is especially acute in the TRB where the sediment is seriously shortening the lifespan of the H.E.P. stations downstream.
Other forms of pollution are relatively uncommon in the majority of the rivers of the TRB, but effluent from coffee processing factories sited on headwater streams is reducing water quality for irrigation and processing of the coffee, and causing considerable economic loss. This situation is now being ameliorated with funds provided by international aid organizations (Kenya, 1975).
Assessment of the impacts of basin development on river fisheries is only possible when adequate long-term fisheries statistics are available. The collection of reliable catch statistics from rivers is notoriously difficult, the more so when the contribution by rivers to the total annual inland water catch is small. During the period 1971–77, inclusive, river catches recorded amounted to less than 5 percent by weight of the total landings from inland waters which averaged 27 075 t/y during this period. River catches have declined from over 1 500 t/y prior to 1975 to less than 100 t in 1977 (Kenya, 1971–77). Whether this decline can be attributed to a real decline in river yield or to a reduction in the intensity of data collection is in doubt, but it would appear that river fisheries would not repay the additional expense and effort incurred by more intensive data collection in Kenya.
The data on the yield of river fisheries are collected by the Kenya Fisheries Department and represents the off-take from the more important fish landing sites located on the larger rivers, the Tana and Athi in the east and the Nzoia, Sondu and Kuja, amongst others in the west. The invisible yield (Welcomme, 1976) from the numerous smaller tributaries and streams and which is directly consumed by the local populace is totally unmonitored, but likely from circumstantial evidence to be substantial (Welcomme, 1976). It may be concluded, therefore, that although the official figures for river catches are small, they represent only a minor fraction of the total biomass of fish removed from running waters in Kenya. River fisheries must in consequence be incorporated effectively in the cost benefit analyses of multipurpose developments of river basins to protect and foster this important and cheap resource for the inhabitants of the area being developed.
Even in the absence of adequate data, it can be seen that in the Tana River the condition of the fishery can be fairly directly related to the development of the river. The absence of passes for migrating fish including the eel (Anguilla spp.) around the lowest of the dams at Kindaruma has effectively precluded these long-distance migrants from the upper river where they once lived. Eels are still caught in the most upstream dam at Kamburu, but presumably represent the survivors from the pre-impoundment population trapped upriver. It is probable, therefore, that in due course the eel will disappear from the upper Tana basin unless remedial action allows elvers to successfully by-pass the Tana dams.
The regulatory effects of the dams, which will become more pronounced after the closure of the Upper Reservoir, may be expected to adversely affect the floodplain fisheries of the lower Tana, but the evidence here is equivocal. A computer simulation model (Tana River Development Authority, 1976) predicts that the number of floodless years will be doubled and the frequency of extremely low flows reduced by a factor of about three. However, extreme flood peaks will occur as before because more than half of the Tana flood water originates below the most downstream dam at Kindaruma, and because the total capacity of all the dams is limited. The overall effect of the regulation will be to level the peaks and troughs in river flow, truncating all but the highest flood peaks and reducing the incidence of exceptionally low flows by the controlled release of compensation water from the dams.
This situation will be parallelled in the Athi-Sabaki River, if and when the proposed regulatory and storage dams are completed on that river system. In both the Tana and the Athi-Sabaki river basins the fish are purely riverine and seasonally migrate laterally into floodplain lakes (locally called ziwas), either prior to, or for the purpose of breeding (Whitehead, 1960). The breeding adults often arrive in the lower reaches of the river either from upstream or from ziwas; directly a link has been established with the river. Spawning may take place in the lakes, streams, or ziwas, but only occasionally in the river itself. While retained in the floodplain lakes, the fish are readily available for exploitation. Estimates made in the early 1950s indicated a possible yield of nearly 300 t from the lower Sabaki River alone. More recent estimates from the Tana and Athi Rivers were not available at the time of writing.
The establishment of lacustrine conditions in the dams on the Tana River has led to the development of lake fisheries, particularly in Kamburu and Kindaruma, where Tilapia dominate the catches. These fish will at least partially compensate for any reduction in fish yield from the river fishery downstream. No data are available for the weight of fish landed at Kamburu, but estimates of the expected yield from the Upper Reservoir indicate an annual total of approximately 400 t (Tana River Development Authority, 1976).
In the rivers of the LVB the relationship between basin development and the reported decline in the yield of the river and lake fisheries is more difficult to establish, partly because of the lack of data on fish yield from the rivers and partly because several possible impacts may be operating in concert. The fish taken from the Nyanza rivers are almost entirely anadromous species and ascend the rivers from Lake Victoria at the onset of the rainy seasons, usually in late March and October. Prior to the rains these fish, which include Barbus altianalis radcliffi, Labeo victorianus, Schilbe mystus and Alestes nurse, congregate in the river mouths where they are exposed to intensive fishing which continues unabated when they move upstream to their spawning grounds (Whitehead, 1959). The wide variety of indigenous and ingenious fish traps employed by the local fishermen can remove a significant proportion of the unspawned population which will ultimately lead to reduction in the lake stock. Concurrently, the fish that manage to evade the fish traps on their upstream journey may find conditions of water quality and substratum unsuitable and for either reason fail to spawn successfully. Even if successful spawning takes place, the young, which are frequently more susceptible to pollutants, will have to pass downstream through polluted stretches of water to reach the lake where they mature. At present little is known of the tolerance of tropical fish to the pollutants commonly occurring in the rivers in which they usually breed.
Whitehead (1959) reported that in 1959 the river fisheries of Nyanza produced approximately 2 500 t/y and noted that even then they were threatened by two main dangers: first, by overfishing, and second, by modification of river regimes by irrigation schemes, H.E.P. developments and pollution. His warning would appear to have been well founded. Whatever the actual cause or causes, the decline of the river fisheries in the LVB is beyond question and the widely acknowledged overfishing of the lake stocks must be a significant contributory factor.
In conclusion, I would like to take this opportunity to express my personal opinion on three points. First, that the nature of the negative impacts on fisheries, resulting from river basin developments, would appear to be largely well defined and the solutions to these problems reasonably well known and understood; the reason for the persistance and recurrence of these problems is the practical difficulties encountered in implementing these solutions. Implementation is frequently hampered, not only by technical difficulties, but also by adverse political and economic forces. These forces are particularly acute in multi-national river basin developments, a situation which Kenya fortunately does not have to face as Kenya's five river basins are confined within the national borders.
Second, I believe that the management of river basins in Kenya will remain geared to water supply needs and consideration of fisheries interests will always be subordinated to this primary end. Fisheries will, however, benefit indirectly in some cases because water quality will have to be maintained by the implementation of pollution control and abatement policies to protect the limited resources of water that are available for supply.
Finally, I would suggest that if river management concentrates on, and succeeds in maintaining a high standard of water quality, fisheries management and production may then be most profitably conducted in river basins using aquaculture techniques based on the high quality water thus made available.
Kenya, 1971–77 Fisheries Department, Statistical tables
Kenya, 1972 Kenya's National Report to the United Nations on the Human Environment. Nairobi, Government of Kenya
Kenya, 1975 Ministry of Water Development. Recirculation of water combined with land treatment as a solution to the problem of river pollution from coffee factories. Nairobi, Ministry of Water Development
Myers, N., 1980 Kenya's baby boom. New Sci., 18 Sept. issue: 848–50
Ongweny, G.S., 1976 Problems of soil erosion and sedimentation in selected water catchment areas in Kenya with special reference to the Tana River. Paper presented to the United Nations Water Conference, Mar del Plata, Argentina
Ongweny, G.S., 1979 Water resources of Lake Victoria drainage basin in Kenya. In Natural resources and the development of Lake Victoria Basin in Kenya, edited by C.O. Okedi. Occas.Pap.Inst.Dev.Stud.Univ.Nairobi, (34) : 68–84
Ongweny G.S., Water development and environment in Kenya. Consultancy paper for the National Environment Secretariate, Office of the President. UNEP/UNDP/Government of Kenya Project (undated)
Tana River Development Authority, 1976 Report on Upper Reservoir preconstruction environmental study. Nairobi, Government of Kenya
Welcomme, R.L., 1976 Some general and theoretical considerations on the fish yield of African rivers. J.Fish Biol., 8:351–64
Whitehead, P.J.P., 1959 The river fisheries of Kenya. Part 1. Nyanza Province. E.Afr.Agric. For.J., 24:274–8
Whitehead, P.J.P., 1960 The river fisheries of Kenya. Part 2. The lower Athi (Sabaki) River. E.Afr.Agric.For.J., 25(4):259–65
by
I. Amusu
Federal Department of Fisheries
Victoria Island
Lagos, Nigeria
Abstract |
| The history of fisheries development activities in Nigeria is relatively recent compared to agriculture, animal husbandry and forestry. As a means for accelerated development and management of river basins in Nigeria, 11 River Basin Development Authorities were established in 1976 with the purpose of providing water for irrigation and domestic water supply, improvement of navigation, generation of power, recreation, and fisheries. The Federal Department of Fisheries works in collaboration with the River Basin Development Authorities to promote fishery development through a number of different kinds of projects which provide financial and technical assistance to capture fisheries and in commercial and small-scale fish farming. |
| In spite of the great potential of the resources and the intensive efforts underway in fishery development and management, there are a number of problems which include the large number of fishermen to be assisted, some 400 000, and the fact they are widely dispersed in many remote areas. Staff at the extension level are scarce, and data necessary for planning are not readily available. |
Résumé |
| Les activités de développement de la pêche au Nigéria sont relativement récentes, par comparaison avec l'agriculture, l'élevage et la foresterie. En vue d'accélérer la mise en valeur et l'aménagement des bassins hydrographiques du Nigéria, il a été crée en 1976 onze offices spécialisés, ayant pour objectifs l'approvisionnement en eau pour l'irrigation et les usages domestiques, l'amélioration de la navigation, la production d'electricité, les activités récréatives et la pêche. La Département fédéral des pêcheries s'efforce de promouvoir le développement des pêcheries en collaboration avec ces offices au moyen d'un certain nombre de projets d'aide financière et technique à la pêche et à l'aquiculture commerciale et artisanale. |
| Malgré l'importance des ressources potentielles et l'intensité des efforts actuels en vue de développer et d'aménager les pêcheries, il subsiste un certain nombre de problèmes liés notamment au grand nombre de pêcheurs qui ont besoin d'une aide (400 000 environ) et à leur extrême dispersion géographique dans des régions souvent éloignées. Le personnel de vulgarisation est insuffisant et les données nécessaires à la planification ne sont pas faciles à obtenir. |
The history of fisheries development activities in Nigeria is relatively recent compared to agriculture, animal husbandry and forestry. The present development-orientated Federal Department of Fisheries is the agency responsible for the implementation of the Federal Government fisheries programmes, and it came into being only in 1976, as part of the measures taken to given effect to the Federal Government policy of accelerating food production in the country.
Fisheries development and management in river basins entails capture of fisheries in rivers and lakes, and fish farming on the floodplains. Riverine fisheries in Nigeria have for years been at a subsistence level, while fish farming has only been recently introduced. A few small fish farms were in existence before the Federal Department of Fisheries came into being, but they were mainly used for research purposes.
An FAO survey of Nigeria shows that mangrove swamps of the Niger Delta cover an area of about 750 000 ha, and a large part of this could be converted to brackishwater fish ponds.
The irrigation dams and reservoirs being built by the various River Basin Development Authorities could be stocked with fingerlings from our Fish Seed Multiplication Project.
The introduction of rice field/fish culture could be considered for some of the large rice projects being implemented by some River Basin Development Authorities.
Large fish farm projects could be sited in some of the river basins in the country, and since these areas come under the jurisdiction of the River Basin Development Authorities, these Authorities could implement more fishery projects.
For the riverine fisheries, modern fishing imputs could be made available at a subsidized rate to the artisanal fishermen to induce increased fish production.
In 1976, 11 River Basin Development Authorities were established to ensure the effective exploitation of the inland water resources in the country; these are (Figure 1):
The purposes for their establishment included:
This is accomplished through surface impoundment of waters by constructing small, medium and large dams. Meanwhile, the attention of the River Basin Development Authorities is mainly on irrigation. The Federal Department of Fisheries in collaboration with these River Basin Development Authorities is carrying out fishery development throughout the country, including in these river basins.
Figure 1 Map of Nigeria showing major rivers
The need for the development of fisheries in the river basins cannot be overemphasized as it is essential for complimenting the production from marine sources, hence the Federal Department of Fisheries has carefully designed development projects to achieve this objective.
For ease of management, the underlisted development projects are located at strategic points in the country, as shown in the map (Figure 2).
Figure 2 Map of Nigeria showing Federal Inland Fisheries Development Projects
This project aims at bringing the advantages of modern technology of about 400 000 Nigerian artisanal fishermen. Essential fishing inputs have been supplied in a package form and at 50 percent subsidy to the local fishermen, so as to induce increased fish production in the inland waters, including the river basins. In addition, infrastructural facilities, like landing bases, stores, fuel depots, workshops and improved smoking kilns are provided under this project.
Some of the fishing inputs distributed so far include: outboard engines; fishing nets; nylon ropes; hooks; twine; navigation bouys; floats, and lead sheets.
Under this project, financial releases were made to the various States' Ministries of Agriculture and National Resources, to offer assistance in form of grants and subsidies for the construction, rehabilitation and maintenance of fish ponds, as well as for fishing operations all over the country. So far, more than Naira 2.1 million has been released under this project.
The effects of the National Accelerated Fish Production Project and the Special Fisheries Development Project can be seen in Table 1.
Table 1
Nigerian fish supplies by the Artisanal Sector 1971–79
(unit in t)
| 1971 | 1972 | 1973 | 1974 | 1975 | 1976 | 1977 | 1978 | 1979 | ||||||||||
| Total | 405 | 129 | 433 | 767 | 459 | 616 | 465 | 444 | 496 | 059 | 486 | 159 | 488 | 022 | 501 | 414 | 524 | 127 |
| Artisanal | ||||||||||||||||||
| (i) Coastal and brackish water | 199 | 639 | 218 | 738 | 228 | 411 | 226 | 094 | 256 | 034 | 245 | 336 | 247 | 858 | 255 | 426 | 264 | 495 |
| (ii) Inland rivers and lakes | 205 | 490 | 215 | 029 | 231 | 205 | 239 | 350 | 240 | 025 | 240 | 823 | 240 | 164 | 245 | 986 | 259 | 632 |
This project is designed to solve the fish seed problem which aquaculture development is facing in this country. Under it, high-quality fish seeds of local and some well-accepted exotic fish species are being produced.
The project is being implemented at 10 locations in the country; they are:
| Naska | - | Kaduna State |
| Oyo | - | Oyo State |
| Bagauda | - | Kano State |
| Akure | - | Ondo State |
| Umuna/Okigwe | - | Imo State |
| Odeda | - | Ogun State |
| Agbor | - | Bendel State |
| Etinan | - | Cross River State |
| Panyam | - | Plateau State |
| Wamako | - | Sokoto State |
Out of these 10 existing centres, two are quite large with a target production of 1 million fingerlings each, while the other eight are smaller, with an average target production of 250 000 fingerlings each. Some of these centres have already met their targets and production still continues.
In addition, two new large centres are under construction at Bakolori (Sokoto State) and Tiga in Kano State.
Several irrigation dams and reservoirs, some of which are built by the River Basin Development Authorities, have been stocked with fingerlings from the Fish Seed Multiplication Project. It is envisaged that with the completion of the two large centres, now under construction, there will be enough fingerlings to stock the fish farms, dams and reservoirs which are springing up.
The centre under construction at Bakolori is being implemented by the Federal Department of Fisheries and the Sokoto-Rima Basin Development Authority.
After a survey of the whole country in 1978, by the Asiaphil Fisheries Corporation of Manila, Philippines, a recommendation for the establishment of two types of fish farms was made; these were:
The Small-Scale Model Fish Farms, and
The Large-Scale Commercial Fish Farms.
The Small-Scale Model Fish Farms
The Small-Scale Model Fish Farms are starting off with 10–12 ha each and are expected to be at least 50 ha each when fully completed. The fish farms belong to the Federal Government and are purely for fish production. One of the main objectives is for these fish farms to serve as models, demonstrating the economic viability of fish farming. These fish farms are sited in five states, while the sixth site is in the form of pen/cage culture which is to be carried out in four different dams in Kaduna State. At a production figure of about 2 ½ t/ha/y; it is expected that the small-scale model fish farms would produce about 650 t of fish/y.
Large-Scale Commercial Fish Farms
Three of these large-scale commercial fish farms were recommended for immediate implementation. For better coordination, and to avoid duplication of efforts, this aspect of the fish farm project had been handed over to the various River Basin Development Authorities under whose jurisdiction the areas fall.
The fish farms are expected to be about 500 ha each, and it is pleasing to note that two of these River Basin Development Authorities have started the implementation of this project.
When fully operational, and at a production figure of about 2 ½ t/ha/y, these three fish farms would produce about 3.750 t of fish/y.
Toward effective management, the Federal Department of Fisheries embarked on regular training of technicians and professionals, both locally and overseas. The training covers a wide range of fields, from aquaculture to fisheries management, fisheries inspection, boat building, etc. The training courses are related to both inland and offshore fisheries development.
To ensure a rational development, management and conservation of Nigeria's inland fisheries resources, an Inland Fisheries Decree has been drafted. Its provisions are being popularized all over the country. One of these is the campaign against the use of destructive fishing methods in inland waters. There is an Inspectorate Unit of the Federal Department of Fisheries which is responsible for enforcing the regulations of both the Inland and Offshore Fisheries Decrees.
Despite the very great potential and the development and management efforts being made, there are still problems encountered during the implementation of these projects.
The fishermen who number about 400 000 are scattered all over the country. They are traditional fishermen and have many different fishing locations. This makes it difficult to bring them together in form of Cooperative Societies.
This also makes it difficult to reach them with fishing inputs. Apart from being widespread, they live in very remote areas and this makes them inaccessible too. Because they live in remote areas, it is not easy to get their catches to the consumers, and because there are no effective means of preserving their catches, some of their fish get to the market in a rather poor state.
There seems to have been a communication gap between the River Basin Development Authorities and the Federal Department of Fisheries at the planning stages. In constructing reservoirs, the possibilities of exploiting them for fisheries activities seem not to be taken into consideration, and this hampers fisheries development in such reservoirs.
Manpower shortage is another major problem. There is inadequate aquaculture personnel to man the government aquacultural projects. Extension service workers are also short.
Raw data which are needed for adequate planning are not readily available. There is also inadequate financial resources on the part of the local fishermen to improve their largely subsistence fishing.
