Department of Zoology
University of Dar-es-Salaam
P.O. Box 35064
|The present and potential fisheries of the Rufiji basin are reviewed, Impacts on fisheries of a variety of development projects are briefly assessed, including hydroelectric dams, irrigated agriculture, a pulp mill, municipal water supply systems and national parks and game reserves. Some social, organizational and economic factors which may be crucial for a successful mating between industry and fisheries are discussed. A River Basin Fishery Master Plan is advocated as a potentially useful tool in the development and conservation of river basin fisheries. It is suggested that the extent of participation of impact area residents in the planning and decision-making stages of an industrial development project could prove decisive to the success or failure of the project. It is concluded that industrialization of a river basin need not necessarily result in losses in fish production, but rather could result in boosts in fish production provided that the various technical and non-technical problems involved can be solved.|
|L'auteur étudie l'importance actuelle et potentielle de la pêche dans le bassin de la Rufiji et il évoque brièvement les répercussions que pourraient avoir sur la pêche un certain nombre de projects de développement (barrages hydroélectriques, programme d'irrigation, fabrique de pâte à papier, systèmes municipaux d'adduction d'eau, parcs nationaux et réserves de chasse). L'auteur passe en revue un certain nombre de facteurs sociaux, organisationnels et économiques qui peuvent être déterminants pour concilier les impératifs de l'industrialisation et de la pêche. Il préconise l'adoption d'un plan directeur qui pourrait s'avérer particulièrement utile pour la mise en valeur et la préservation des ressources en poisson du bassin et il estime que le degré de participation de la population locale concernée à la planification et à la prise des décisions, dans un projet de développement industriel, peut avoir une influence décisive sur le succès ou l'échec du projet. L'auteur conclut que l'industrialisation d'un bassin fluvial n'entraînera pas nécessairement une baisse de la production de poisson mais peut au contraire se solder par des gains de production, à condition qu'on puisse résoudre les divers problèmes techniques ou non que cela implique.|
The Rufiji River basin (Figure 1) is the largest and single-most important river basin in Tanzania, occupying 20 percent of the land area and receiving one third of the total national rainfall. It is centrally situated and although containing only one major urban centre, Iringa (population of 61 000) several others are located in close proximity to the basin's borders (i.e., Dar-es-Salaam, Morogoro, Mbeya, Songea and the national capital, Dodoma). The basin has considerable potential for hydroelectric, industrial, agricultural, fishery and tourism development, as well as for the supply of municipal water needs. Various types of development projects have been completed or are under construction, while others are planned for the future.
In 1975 the Government of Tanzania created, by an act of Parliament, the Rufiji Basin Development Authority (RUBADA), authorized to plan and coordinate the development activities in the Rufiji basin. Included in RUBADA's terms of reference is:“to promote and regulate fishing industry in the rivers, lakes and dams within the development area” (RUBADA, 1977).
Figure 1 Rufiji River basin, including Mtera, Kidatu and proposed Stiegler's Gorge reservoirs.
In a climate of intensive and varied development, the freshwater fishing industry of a river basin may be particularly vulnerable. The special requirements of the industry severly limit the types of modifications to water quality and hydrological cycles that would be compatible with maximum fish yields and would otherwise be permissible for other industries and water usages. This paper briefly surveys the existing and potential fisheries of the Rufiji basin, examines the possible effects of various development projects on fish yields and suggests ways in which detrimental effects could be minimized.
Physical features relevant to fisheries are given in Table 1. The basin consists of three major tributary basins (Great Ruaha in the north and west, Kilombero in the centre-west, and Luwegu in the south) and the main Rufiji River. Rainfall is largely restricted to a short rainy season in December and January and a longer, more intense rainy season from March to May. There are three major floodplains: Usangu (also called Bohoro Flats), Kilombero and Rufiji.
The numerous headwater streams of the upper Great Ruaha basin discharge on to the large Usangu plain (Figure 2). The latter has an area of 4 400 km2 and contains the permanent Utengule Swamp (518 km2) in its lower region. In the past moderate floodplain fishing activity took place, but this has since declined to a low level primarily due to poor accessibility by road (Mwaiseje and Rodgers, pers. comm.). Other than Wildekamp's (1978) observation of spear fishing for Clarias sp., no concrete information is available about the fish fauna or present fishery on the Usangu floodplain.
It is probably correct to assume that migratory fish stocks inhabiting at least the upper reach of the Great Ruaha River migrate to the Usangu floodplain to spawn during the rainy season. The Great Ruaha fish fauna is diverse (Table 2) and it is suggested that the Usangu floodplain has the potential to support a highly productive fishery. The approximate area inundated is unknown. FAO (1961) only record that widespread flooding occurs during the rainy season and Wildekamp states that “the whole Savanna is flooded” during the rains. Assuming that 75 percent of the area is flooded (3 300 km2), Welcomme's (1978:271) equation correlating floodplain catch with floodplain area predicts a potential yield of up to 12 600 t/y. This is a substantial quantity of fish and a fishery feasibility study is clearly indicated.
The Usangu floodplain also has a high agricultural potential. FAO (1961) determined that 2 100 km2 (48 percent of the area) are suitable for irrigated agriculture provided total flood control is achieved. Total flood control is, however, completely incompatible with floodplain fish production and fisheries, and it is debatable if this is the most economical approach to realizing the agricultural potential of the Usangu floodplain. Construction of dams with sufficient storage capacity to achieve total flood control on a large number of the affluent streams is likely to be extremely costly. A better alternative might be to regulate the natural floods to levels compatible with the requirements of the wet season crop (rice) and to employ pumped irrigation only for dry season crops. Such an irrigation scheme would reduce slightly the long-term mean annual fish yield by eliminating the very high flood discharges responsible for bumper catches, but would still allow a substantial floodplain fishery to exist on the Usangu plain. The expansion of irrigated agriculture on the plain has been slow in comparison with the total potential and by 1977 only 16.4 km2 were under irrigation (RUBADA, 1977). This suggests that the floodplain fishery potential will remain relatively undisturbed for a number of years to come, and intensive development of the fishery is feasible. It may be emphasized that any decision to bring about a major expansion in agricultural activity based on flood control should be proceeded by a cost-benefit analysis which takes into account the economic importance of the potential floodplain fishing industry.
Some physical features of the Rufiji River basin
|Catchment area (km2)||Mean annual rainfall range (mm) in headwater area||Mean annual discharge (m3/s)|
|Great Ruaha River tributary basin||84 000||400–1 200||103.0|
|Kilombero River tributary basin||40 000||1 000–2 000||482.8|
|Luwegu River tributary basin||26 000||800–1 000||311.2|
Rufiji River (at Stiegler's Gorge)
Rufiji River (at Indian Ocean)
Data mainly from FAO (1961) and Hafslund (1979)
The total channel length of the Great Ruaha River from the lower margin of the Usangu plain to the Rufiji River confluence is approximately 480 km. Of this, the uppermost 160 km lie within the Ruaha National Park and the lowermost 120 km lie with the Selous Game Reserve. Fishing is prohibited in both of these areas. Fishing does take place in the intermediate 200 km stretch and statistics are available from the Mtera area (Table 3) where the mean annual recorded catch is 52.9 t. Assuming that the Mtera catch comes from a 10-km stretch of river, the yield is 5.29 t/km. This suggests that the total potential yield from the Great Ruaha River may be as high as 2 500 t/y. The park and reserve effectively (but not destructively) remove 1 500 t/y from this potential. This may be viewed as representing a loss of mean annual per caput consumption of 30 kg of fish (twice the national average of 15 kg; see Bernacsek, 1980) to the diets of 50 000 people. While few may be prepared to argue against the setting aside of areas of land and water for the preservation of unique natural heritages, it may be suggested that some creative thought could be expended on how this fish resource could be harvested without undermining the basic structures and functions of a park or reserve and without significant disturbance of wildelife. As noted below, this problem is not restricted to the Great Ruaha River. Approaches to controlled harvesting could include seasonal fishing to take advantage of stock migration and night-time fishing, both within restricted areas.
An important hydroelectric scheme on the Great Ruaha River is presently in its final stage of construction. It will consist of a large storage head tank reservoir at Mtera and the main power generating dam downstream at Kidatu. Expected physical characteristics of the two dams and reservoirs and predicted potential fish yields are given in Table 4. The predicted stabilized annual catch for the large and shallow Mtera reservoir (Figure 3) is 3 000–7 000 t while the small and deep Kidatu reservoir might produce only 61–140 t. The Mtera yield will represent a substantial boost to Great Ruaha fishery potential. No major detrimental downstream effects are expected due to impoundment since the river does not develop any large floodplains in the downstream area and it supplies only 11 percent of the lower Rufiji River discharge. Neither dam will have a fish ladder. The production of some migratory species resident below each dam is therefore expected to decline since these stocks will presumably no longer have access to floodplain spawning and nursery grounds upstream.
Figure 2 Great Ruaha River tributary basin
Commercially important (or potentially important) fish species occurring in the Rufiji River basin. The fish fauna of the Luwegu River tributary basin is completely unknown
|Family, genus and species||Great Ruaha tributary basin||Kilombero tributary basin||Rufiji River|
|Protopterus aethiopicus Owen||X||-||-|
|Mormyrus hasselquistii Cuv. and Valen.||-||-||X|
|M. cf kannume Försk||-||-||X|
|M. longirostris Peters||X||X||-|
|Hippopotamyrus discorhynchus (Peters)||X||-||-|
|Gnathonemus livingstonii Blgr.||X||-||X|
|G. macrolepidotus (Peters)||X||-||-|
|Megalops cyprinoides (Broussonet)||-||-||X|
|Anguilla nebulosa labiata Peters||X||-||-|
|Anguilla sp. indet.||-||-||X|
|Salmo gairdneri Richardson1||X||-||-|
|S. trutta Linn.1||X||-||-|
|Hydrocynus vittatus Castelnau||X||X||X|
|Alestes affinis Gunther||X||X||X|
|A. lateralis Blgr.||-||-||X|
|A. stuhlmanni Pfeffer||-||X||X|
|Petersius conserialis Hilgendorf||-||-||X|
|Distichodus petersii Pfeffer||X||X||X|
|D. rufigiensis Norman||X||-||X|
|Citharinus congicus Blgr.||X||X||X|
|Barbus macrolepis Pfeffer||X||X||X|
|B. oxyrhynchus Pfeffer||X||-||-|
|Labeo cylindricus Peters||X||-||X|
|L. ulangensis Steindachner||X||X||X|
|Labeo sp. indet.||X||X||X|
|Opsaridium loveridgei (Norman)||X||-||X|
|Bagrus orientalis Blgr.||X||X||X|
|Eutropius mobiusii Pfeffer||X||X||X|
|Schilbe mystus (Linn.)||X||X||-|
|Heterobranchus longifilis Valen.||-||-||X|
|Clarias mossambicus Peters||X||X||X|
|C. theodorae Weber||-||-||X|
|Synodontis fuelleborni Hilgendorf||-||X||X|
|S. maculipinnis Norman||X||X||X|
|S. matthesi Poll||X||-||-|
|S. rufigiensis Bailey||-||-||X|
|Micropterus salmoides (Lacep.)1||X||-||-|
|Sarotherodon esculenta (Graham)1||X||-||-|
|S. urolepis (Norman)||-||X||X|
|Sarotherodon sp. indet.1||X||-||-|
|Tilapia rendalli (Blgr.)1||X||-||-|
|T. zillii (Gervais)1||X||-||-|
|Eleotris fusca (Bloch and Schneider)||-||-||X|
|Glossogobius giuris (Hamilton Buchanan)||-||-||X|
Based on Matthes (1967), Bailey (1969), Petr (1974, 1976), Hopson (1979) and Bernacsek (1980, 1980a, 1980b, 1980c)
Fish yields (t) from the Rufiji basin. Data from Annual Reports of the Fisheries Division, Ministry of Natural Resources and Animal Production
|Year||Great Ruaha River (Mtera area)||Kilombero floodplain||Rufiji floodplain|
|1971||41.0||1 000||2 700|
|Annual mean||52.9||4 660||3 582|
|Total mean annual recorded catch for Rufiji basin: 8 295 t|
NA: Not available
Bernacsek (1980a) and Havnevik (1980)
Some features and predicted fish catches from Mtera and Kidatu reservoirs, Great Ruaha tributary basin
|(Expected) date of dam closure||December 1980||November 1975|
|Generating capacity (MW)||60||200|
|Dam height (m)||45||40|
|Mean regulated volume (km3)||1.80||0.165|
|Mean regulated area (km2)||360||9.6|
|Mean regulated mean depth (m)||5.00||17.2|
|Conductivity (micromhos/cm at 20°C)||214||409|
|MEI (morphedaphic index)||42.8||23.8|
|Predicted peak bloom catch (t/y)||4 800–31 400||-|
|Predicted stabilized catch (t/y)||3 000– 7 000||61–140|
Data from Bernacsek (1980b)
The problem could be alleviated by installing fish ladders. Failing this, the deficit (unlikely to exceed 1 000 t/y) can easily be made up from the potential Mtera catch. The rate of survival to maturity of migratory fish species resident in the Mtera reservoir during the dry season is likely to be much higher than it was in the unimpounded river. This should result in much larger spawning migration runs up to the Usangu floodplain and therefore increase the potential floodplain fishery yield there. A corollary to this is that flood control on the Usangu plain would adversely effect fish production in the Mtera reservoir.
One, and possibly two, urban areas will extract municipal water supplies from the Great Ruaha basin. The Iringa Urban Master Plan calls for the extraction of water from the Little Ruaha River to service an estimated population of 32 700 by the year 2000 in the central business district. Sewage will be treated in stabilization ponds and then possibly be used for irrigation. Returns to the river channel will be marginal at best. Dodoma presently obtains its water supply from local underground sources, but these will likely be insufficient to meet future population growth needs. One option is to pipe water from the Mtera reservoir. It is likely that irrigation water for the dry Dodoma area will similarly be obtained. If large-scale increases in such consumptive water usages occur in the future, some depression of fish yields from the Great Ruaha basin will be unavoidable.
The system of numerous headwater streams discharging on to a large floodplain which occurs in the upper Great Ruaha basin is duplicated in the upper Kilombero basin (Figure 4). The Kilombero valley floodplain is larger in area (6 736 km2) and contains the permanent Kibasira Swamp (89 km2 in 1962, but has increased substantially in area in recent years; Rodgers, pers. comm.). A highly productive fishery operates on the Kilombero floodplain (Hopson, 1979:6). The highest recorded catch was 8 549 t in 1976 (Table 3). FAO (1961) notes that the Kilombero valley is flooded for extensive periods every year. A potential yield of about 25 800 t/y is predicted by Welcomme's equation.
FAO (1961) considered the potentially irrigable area of the Kilombero floodplain to be 3 335 km2 (50 percent of the area), but by 1977 only 14 km2 were under irrigation. The feasibility for full flood control on the Kilombero floodplain is likely to be even less than for the Usangu floodplain due to the more intense rainfall in the catchment area of the former
Figure 3 Mtera reservoir
Figure 4 Kilombero River tributary basin
Of considerably greater concern is the construction of a 176 t/d bleached kraft plus stone groundwood pulp mill near Mufindi which is expected to reach full capacity by 1987. The treated mill effluent will be discharged into the small North Ruaha River some 100 km upstream from the rich fishing grounds of the Kilombero floodplain. The present design of the treatment system has been criticized by Bernacsek (1980c) as being inadequate to protect the downstream fish stocks from sublethal effects of chlorinated wastes. Aeration lagooning is largely ineffective for removing highly toxic and non-biodegradable compounds such as chlorinated guaiacols and resin acids (Leach and Thakore, 1975; Landner, 1976; British Colombia Research, 1976). Such contaminants may be expected to accumulate in fish tissue (perhaps to an extent making it unfit for human consumption) and in sediments (thus partly trapping the toxicants within the river basin). A solution to this problem is either construction of a tertiary treatment system (for example, using the activated charcoal process) or use of an alternative, environmentally more acceptable bleaching process (i.e., oxygen bleaching or a closed bleach plant). The choice of traditional chlorine bleaching is regrettable, and at this late stage the second alternative may no longer be feasible. The potential effect of the Mufindi pulp mill on Rufiji basin fish yields is identified as the single most serious problem facing the basin's fishing industry, and one that needs further attention in the immediate future. There should be a review of the relevant literature and studies should begin on the treatment of a simulated effluent and its effects on indigenous fish species under African conditions. Since the Kilombero floodplain is potentially the most productive fishing ground in the entire Rufiji basin every effort must be made to protect the floodplain and its fish stocks from adverse effects of water pollution.
The Kilombero River, from the lower margin of the Kilombero floodplain to the Luwegu River confluence, is about 85 km long and is situated within the Selous Game Reserve. The potential yield from the river during the dry season may be substantial but cannot be harvested due to the prohibition on fishing in the Selous. This problem was discussed above in connexion with the Great Ruaha River.
Almost the entire Luwegu basin, except for a small portion in the southwest, lies within the Selous Game Reserve (Figure 5). No fisheries exist in the basin and no information is available on the fish fauna and potential fish yield. No extensive floodplains are developed in the basin and this suggests that the potential yield may be disproportionately smaller than for the other two basins. Based on catchment area a potential yield of at least 700 t/y is predicted using the catch versus river basin catchment area equation determined by Welcomme (1978:268), but a field survey is required to establish more reliably the true potential. The discharge of the Luwegu River is substantial and multipurpose impoundments could boost the fishery potential considerably. Again, the problem of exploiting fish stocks situated within parks or reserves must be solved before the potential yield of the Luwegu basin can be realized.
From the Kilombero-Luwegu Rivers confluence to the Rufiji delta, the Rufiji River has a channel length of about 300 km. The entire upper section and the Internal Delta area of the lower section (below Stiegler's Gorge) of the river are situated within the Selous Game Reserve. A floodplain (1 450 km2) is developed in the lower section (Figure 6) which supports an active fishery described recently by Hopson (1979) and Bernacsek (1980a). A series of small permanent lakes on the floodplain contribute substantially to the dry season catch. Estimated yields (Table 3) are somewhat less than the 5 600 t predicted by Welcomme's equation. FAO (1961) considered 809 km2 (56 percent of the area) as suitable for irrigated agriculture.
A major hydroelectric project at Stiegler's Gorge is in the planning stage. The dam is being designed for multipurpose use, including electricity generation, flood control, irrigation agriculture and fishery. The dam will result in a flood probability of only 6 out of 22 years on the Rufiji floodplain compared to 19 out of 22 years prior to impoundment. Bernacsek (1980a) predicted long-term declines of at least 42–58 percent in floodplain fish catches. Since the dam will not be able to eliminate flood risk and as current agricultural practices on the floodplain are attuned to sequential wet and dry season crops (the former irrigated, of course, by natural floods), serious consideration is being given to the annual release of artificial floods for irrigation even though this may reduce somewhat the hydroelectric output. The effect of river bed erosion will however progressively increase, over time, the regulated flood discharge required to produce adequate flooding, and eventually a stage may be reached where regulated flooding becomes incompatible with even minimum economical power generation. The long-term prospects for the Rufiji floodplain fishery are therefore poor. Bernacsek (1980a) suggested that provisions should be made to conserve water levels in the small permanent floodplain lakes. Catches of possibly as much as 1 000 t/y might be obtained from the lakes and the main river channel, while the residual deficit could be made up from reservoir and/or marine yields. Since the Stiegler's Gorge dam will isolate the lower Rufiji fish stocks from the rest of the basin, the Internal Delta will represent the only long-term prospect for breeding and nursery grounds for migratory species of the lower Rufiji. The Internal Delta should therefore be designated a fish sanctuary. The hydrological regime of the Internal Delta could easily be maintained by the release annually of a very short duration flood.
Figure 5 Luwegu River tributary basin
Figure 6 Lower Rufiji River floodplain
The Stiegler's Gorge dam will create a large reservoir (Figure 7) whose water level will be raised after a period of about 15 years by the addition of saddle dams. Expected physical characteristics of the dam and reservoir and potential catch are presented in Table 5. The fish fauna is expected to be diverse and will likely include a pelagic characid community. The predicted stabilized Stage 2 catch is 5 100–8 200 t/y. This should be sufficient to exceed deficits from the Rufiji floodplain. FAO (1961) noted that if complete flood control on the Rufiji floodplain is an objective, then this might be achieved by construction of an additional dam - on the upper Kilombero River at Kingenenas. Bernacsek (1980a) predicted that this could result in stabilized Stage 2 catches rising to about 7 700–11 800 t/y in the Stiegler's Gorge reservoir due to increased conductivity and a higher more stable mean regulated water level resulting in a greater reservoir surface area. The Kingenenas reservoir itself could add substantially to the Rufiji basin yield and it was speculated that the combination of Kingenenas reservoir and Kilombero floodplain adjacent aquatic systems might synergistically produce ‘super’ high yields. The Kingenenas dam would have to include some provision to give migratory fish species in the Stiegler's Gorge reservoir access to the Kilombero floodplain spawning grounds.
The Mufindi pulp mill is expected to have an effect on the Stiegler's Gorge reservoir fishery since the reservoir will trap upward of 15 million tons of sediment per year. If the sediment is contaminated with chlorinated organic toxins, these compounds will enter the reservoir's food chain. Detritivores and piscivores may exhibit the highest accumulation of toxicants in their body tissues.
The objective of rational river basin fishery management may be defined as optimal sustainable exploitation and protection of all available stocks. This may be difficult enough to achieve in an unaltered basin. In a basin such as the Rufiji, which is undergoing complex development, the problems are formidable. The majority of the technical problems which must be overcome to allow a successful or satisfactory mating between industry (senso lato) and freshwater fisheries are well known from experience elsewhere and are likely to be resolvable. In some cases a loss in fish yield may have to be tolerated (i.e., Rufiji floodplain) if the benefits realized from other production sections are judged of greater importance. However, the factors which may be crucial for achieving coexistence between fisheries and industry are not necessarily technical but social, organizational and economic. Four such factors, discussed below, are identified as being of crucial importance.
Figure 7 Upper Rufiji River and proposed Stiegler's Gorge reservoir
Some features and predicted fish catches from the proposed Stiegler's Gorge reservoir, Rufiji River
(without saddle dams)
(with saddle dams)
|(Expected) date of dam closure||1987||2004|
|Generating capacity (MW)||900||1 200|
|Dam height (m)||134||134|
|Mean regulated volume (km3)||15.3||23.2|
|Mean regulated area (km2)||760||923|
|Mean regulated mean depth (m)||20.1||25.1|
|Conductivity (micromhos/cm at 20°C)||216||216|
|MEI (morphedaphic index)||10.7||8.61|
|Predicted peak bloom catch (t/y)||7 400–27 200||5 400–10 100|
|Predicted stabilized catch (t/y)||4 600– 7 500||5 100– 8 200|
Data from Bernacsek (1980a)
River basin fisheries are mainly artisanal in nature, partly commercial and partly subsistence. They are not ‘modernistic’ compared to, for example, a freezer trawler fleet. In some areas the fishing profession may have a social stigma attached to it. A proportion of the fishermen are migratory or non-professionals. Fishermen rarely form socio-economic organizations or associations which could have a collective voice in planning the expansion and/or protection of their industry. The lobbying power of the industry may be almost nil as a result. This lack of collective organization is undoubtedly an important factor in preventing fishermen and their industry from achieving higher status within the social and economic milieu of the nation as a whole. It may also stunt the growth of occupational professionalism among fishermen. The establishment of dynamic fishermen associations and collectives should be viewed as of great importance in the consolidation and higher development of the industry.
The internalized, non-parastatal nature of the industry tends to lower its position in the national economic hierarchy. River basin fisheries usually earn no foreign exchange and realize no tax revenue to the Government. On the other hand, the industry gives employment and respectable incomes (and unlike many types of crop agriculture, a daily cash income flow) to the fishermen and places on the market inexpensively an essential nutritional item-animal protein. National self-reliance must mean first and foremost self-sufficiency in food stuffs. Fish supplies a large proportion of dietary protein in Tanzania and other developing countries and any loss in fish production must be viewed as directly resulting in a decline in per caput animal protein consumption. It is clear that the true economic importance of fish production would be grossly underestimated if analysed solely in monetary terms, although comparison of the costs of locally-harvested fish versus imported fish is, of course, highly favourable to the former.
In Tanzania, due to the high actual and/or potential yields of the Great Lakes and the coastal marine fishing grounds, river basin fisheries tend to be somewhat neglected by management bodies. This is however a poor use of resources since river basin fisheries have several advantages over Great Lakes and marine fisheries. Potential yields are in some cases substantial. For example, the total potential yield from the Rufiji basin exceeds the total Tanzanian marine catch of 46 000 t (Table 6) and is of the same order of magnitude as catches from Tanzanian waters of Lake Victoria (65 000 t) and Lake Tanganyika (62 000 t). Exploitation of small or shallow inland aquatic systems is comparatively inexpensive and often highly efficient (to the extent that overexploitation may easily come about) and transport cost and spoilage losses incurred are generally much smaller since the distances from the fishing grounds to the consumer are usually relatively short (as compared to dispatching marine or Great Lake fish to central inland markets). Investment in river basin fisheries can be viewed as being of comparatively low risk and bringing a high rate of economic return. It is clear that the economic importance and/or potential of river basin fisheries may not be fully recognized by the Government and developers and this lack of recognition impedes the progressive development of these fisheries.
Summary of potential yields from floodplains and reservoirs in the Rufiji basin (t/y)
|Fishing ground||Low estimate||High estimate|
|Usangu||12 600||12 600|
|Kilombero||25 800||25 800|
|Rufiji (post-impoundment)||1 400||2 100|
|Sub-total (% of grand total)||39 800 (83%)||40 500 (73%)|
|Mtera||3 000||7 000|
|Stiegler's Gorge (Stage 2)||5 100||8 200|
|Sub-total (% of grand total)||8 161 (17%)||15 340 (27%)|
|Grand total||47 961||55 840|
Since the problems of fisheries development and protection in an industrially developing river basin are complex and often interdependent, it may be suggested that an effective approach toward comprehensive basin fishery development might be to formulate a Fisheries Master Plan for the basin as a whole. The Master Plan should identify all basin fish resources, present concrete plans for effectively exploiting these resources, analyse the effects of the various ongoing and/or proposed development projects and recommend steps to be taken to minimize or eliminate effects detrimental to fisheries. In the case of the Rufiji basin, RUBADA intends to undertake responsibility for production of such a Fisheries Master Plan, but in other basins in Tanzania and elsewhere the Fisheries Departments could be entrusted with this task. Priority should be given to those basins with the greatest fishery potential yield and/or undergoing the greatest amount of potentially ecologically disruptive development. Considerable accurate baseline data on the physical, chemical, biological, industrial and socio-economic components of the basin are required if the Master Plan is to become an effective instrument in fishery development and conservation. In the case of the Rufiji, a substantial amount of information is already available upon which to base the Master Plan.
Furthermore, legislative incorporation or governmental approval of the Master Plan must be sought and won. This would ensure that all industrial development projects within a river basin must be compatible and integrated with the basin's fishing industry. Most importantly, it would place a river basin fishing industry into a position where it would be able to strongly influence its own long-term future.
In many developing countries, development projects typically involve three parties:
Unfortunately, the planning and decision-making stages which proceed the construction stage often do not include the last party and it may be suggested that a major reason for the failure of some projects is the exclusion of impact area residents from the planning and decision-making processes. Lack of confidence by the other two parties in the ability of impact area residents to critically evaluate the impacts of a project and to responsibly contribute to planning deliberations is almost surely misfounded and the success or failure of the project may in the end rest largely on the contribution of the residents. The experiences, knowledge and aspirations of tens or hundreds of thousands of impact-area residents cannot be ignored in favour of the opinions of a handful of experts and consultants who may have no long-term, vested interest in the success or failure of the project. It should be considered vital (and indeed just) that an increased share of planning and decision making powers be given to impact-area residents and their elected representatives.
In the case of the Rufiji basin, a number of concrete steps have been taken toward this end. Village surveys are conducted by RUBADA on diverse topics related to the development projects. Review meetings and seminars are organized during which there is an exchange of information and problems are freely discussed. All members of Parliament for constituencies situated within the basin are members of RUBADA's governing Board of Directors and are entrusted with expressing the views of their constituents to the Board.
At the same time, a greater appreciation on the part of foreign development agencies and consulting firms of the very profound and far-reaching effects that some types of development projects can have on a developing country must come about. In particular, indiscriminate or inappropriate installation of advanced Western technology can lumber a developing country with massive, long-term environmental problems rectifiable only by very costly salvage operations and with the cost passed on to the future generations. Solving environmental problems is always cheaper to do early on in the development process during the planning stage, rather than later on when a potential problem has become a real problem. Developing countries can advantageously draw on the extensive experience of the developed world in the area of environmental degradation and consequent loss in fish production.
In answer to the question posed by the title of this paper, the prospects for coexistence between fisheries and industry in the Rufiji basin are on balance excellent. Credit must be given to RUBADA for its attempts to identify and conduct research into potential conflict areas and also for taking up these problems with other Governmental bodies (for example, in the case of the potential effects of the Mufindi pulp mill on the Kilombero floodplain fishery). It is the belief of this author that industrialization of a river basin need not necessarily result in a decline in fish yields (as has too often been the experience in the past), but rather, with innovative and appropriate ‘hydro-biological engineering’, fish yields can be boosted. In view of Africa's high population growth rate, achievement of a post-industrialization boost in river basin fish yield should constitute an important part of a nation's food production strategy. Failure to achieve this must be viewed as mismanagement of a valuable renewable resource and should not be interpreted as an inherent and unavoidable result of industrialization.
Bailey, R.G. 1969 The non-cichlid fishes of the eastward flowing rivers of Tanzania, East Africa. Rev.Zool.Bot.Afr., 80(1–2):170–99
British Colombia Research, 1976 Biodegradability of various toxic compounds in pulp and paper effluents. CPAR Rep.For.Serv.Environ.Can., (408–1):45 p.
Bernacsek, G.M., 1980 Introduction to the freshwater fishes of Tanzania. Dar-es-Salaam, University of Dar-es-Salaam, 78 p.
Bernacsek G.M., 1980a The Stiegler's Gorge hydroelectric scheme. Predicted effects on fish yields from the Rufiji River basin, Tanzania. In Report. Fisheries Division of the Ministry of Natural Resources and Tourism and the Rufiji Basin Development Authority.
Bernacsek, G.M., 1980b Assessment of potential fish yields in Mtera and Kidatu reservoirs, Great Ruaha River, Tanzania. In Report. Fisheries Division of the Ministry of Natural Resources and Tourism and the Rufiji Basin Development Authority.
Bernacsek, G.M., 1980c Preliminary assessment of the possible effects of the Mufindi pulp mill on fish yields of the Rufiji basin, Tanzania. In Report. Fisheries Division of the Ministry of Natural Resources and Tourism and the Rufiji Basin Development Authority.
FAO, 1961 The Rufiji Basin, Tanganyika. Report to the Government of Tanganyika. Rome.
Hafslund, A.S., 1979 Stiegler's Gorge power and flood control development. Preliminary project report. Oslo, Hafslund/Norad.
Havnevik, K.J., 1980 Economy and organization in Rufiji District: The case of crafts and extractive activities. BRALUP Res.Pap., Univ.Dar-es-Salaam, (65)
Hopson, A.J., 1979 Report on the freshwater fisheries on the Lower Rufiji River with particular reference to possible changes resulting from modifications to the environment by the proposed dam at Stiegler's Gorge. Technical paper 1, Rome, FAO, FAO/TCP/URT/8806(i):47 p.
Landner, L., 1976 Bioaccumulating, chlorinated substances found in cellulose bleachery effluents. IVL Bull., 5(2):8 p.
Leach, J.M. and A.N. Thakore, 1975 Isolation and identification of constituents toxic to juvenile rainbow trout (Salmo gairdneri) in caustic extraction effluents from kraft pulpmill bleach plants. J.Fish.Res.Board Can., 32(8):1249–57
Matthes, H., 1967 The fish and fisheries of the Ruaha River Basin, Tanzania. (Systematics, ecology, zoogeography, fisheries). EAFFRO Occas.Pap., (9):19 p.
Petr, T., 1974 A pre-impoundment limnological study of the Great Ruaha River (Tanzania) and some of its tributaries (River Yovi and Little Ruaha) in and around the proposed impoundment areas. Report for TANESCO Tanzania. Stockholm, SWECO, 104 p.
Petr, T., 1976 Limnology of the Great Ruaha River above Kidatu. In Ecological studies of the Mtera basin, Stockholm, SWECO, pp. 87–99
RUBADA (Rujiji Basin Development Authority), 1977 A short report on the development of the Rufiji basin. Dar-es-Salaam, Rufiji Basin Development Authority, 17 p.
Welcomme, R.L., 1978 Some factors affecting the catch of tropical river fisheries. CIFA Tech. Pap., (5):266–75
Wildekamp, R.H., 1978 Messages from Tanzania. Part 1. Killi-News Brit.Killifish Assoc., (160):1–4
Ministry of Natural Resources and Tourism
|Among Tanzania's floodplain fisheries, the greatest fishery resource potential lies in the natural waters of the Kilombero River basin. As in other African river basins, the fishes in the basin respond to variations in flooding regimes. The flooding undergoes short-and long-term changes induced by varying weather and climatic patterns. Hence, each flooding pattern affects the fish populations and their availability to the fishery differently. In turn, the fishery is affected, and through it, the local economy in terms of employment, income and economic growth of the region.|
|With a proper development and management policy, additional commercial exploitation of the fisheries would be ideal in view of the high productivity of the natural system, easy accessibility to the main commercial centres in the country and a sufficiently developed infrastructure for the rural area.|
|Future increases in fish supply could be achieved by intensifying fish farming in the area as another development alternative.|
|Parmi toutes les plaines d'inondation de Tanzanie, ce sont les eaux naturelles du bassin de la Kilombero qui recèlent les ressources potentielles en poisson les plus importantes. Comme c'est le cas pour d'autres bassins fluviaux d'Afrique, le poisson réagit aux variations à court et à long terme du régime des crues qui sont elles-mêmes fonction des conditions métérologiques et climatiques; chacune de ces modifications affecte l'ichtyomasse et par conséquent l'importance des prises, avec des répercussions évidentes sur l'économie locale en termes d'emploi, de revenu et de croissance économique régionale.|
|Il doit être possible, grâce à une politique appropriée de mise en valeur et d'aménagement, de développer la pêche commerciale, ce qui constitue la solution idéale compte tenu du taux de reproduction biologique élevé, de la facilité d'accès aux principaux centres commerciaux du pays et de l'existence dans cette région d'une infrastructure rurale suffisamment développée.|
|Pour accroître la production de poisson, une autre solution consisterait à développer la pisciculture dans la région.|
Fish from the freshwater lakes of the country are playing an important role in supplementing the protein deficient diet of the people and in contributing to the economy of the country. Development of the fisheries in Tanzania could lead to increased income in the fisheries sector which could in turn stimulate demand for domestic industrial products, as well as provide employment and earn the sector foreign exchange because of its potential for export of staple fish products to neighbouring countries.
Tanzania's total annual output of all fish is about 165 000 t. Small inland lakes, floodplain fisheries and ponds contribute about 28 000 t annually as shown in Table 1.
Approximate output of all fish per year in Tanzania in 1974
|Lake Tanganyika||52 000|
|Lake Victoria||45 000|
|Indian Ocean||30 000|
|Inland lakes, floodplain fisheries and ponds||38 000|
Source: Annual Report of the Fisheries Division, Ministry of Natural Resources and Tourism, Tanzania, 1975
Most Tanzanians consume meat as a main source of animal protein. Fish is the second source. The demand for fish is increasing and soon pressures will reveal the need to increase production further. This could necessitate exploiting floodplain fisheries which are currently not being adequately managed and exploited. With proper management these could contribute about 50 000 t/y during normal flooding regimes.
Like in most countries, fishing makes only a small contribution to GDP. This is estimated to be about 7 percent for Tanzania.1 The full contribution of the fishery industry to income could be assessed after value added in processing, marketing, distribution and the share of activities in related industries attributable to fishing operations are taken into consideration. But due to the subsistence nature of the fishery industry in Tanzania and the absence of adequate statistical system, it becomes difficult to make any meaningful assessment.
However, fisheries contribute about 17 000 t of the total food consumption in Tanzania, which is 467 000 t. From the nutritional point of view, the contribution of fish as a source of protein to the diet of Tanzanians is especially important.2
1 Tanzania Government Report - The State of the National Economy Government Printer - Dar-es-Salaam
2 1976/77 Report by the Food and Nutrition Centre, Dar-es-Salaam, Tanzania
The Kilombero floodplain fisheries are one of the greatest fishery resource potentials in Tanzania.
The river is preceded by the Kilombero swamps, which are about 40 km wide and about 100 km long. The river meanders through Morogoro and coast regions. The swamps are surrounded by a complex of water courses, channels, small lakes and marshes which extend up to a width of 10 km.
Southeastward the swamps end and the river forms a single channel. Further east the river basin forms an area of about 196 000 km2.
There are about 14 species of fish to be found in the Kilombero River basin. Fish growth in the river is fast due to abundant supplies of food.
About 3 000 people live along the river in communal villages of not less than 250 inhabitants, their major occupation being fishing supplemented with little subsistence agriculture. Fishing is common throughout the plain and is not a seasonal economic activity. In view of its being a permanent activity, the total number of fishermen employed in the fishery tends to fluctuate from year to year only marginally (Table 2).
Over 5 000 t are harvested annually on a subsistence level. The main fishing tribe is the Wandamba who fish along with little farming. Fishing starts with the onset of the annual flood, depending on the method employed.
Traditional fishing methods include longlining and ndaba. Gillnetting is used in lagoon and riverine areas.
Fish catches depend largely on the extent and duration of floods. With low water the stocks concentrate in the river channel. As a result most of the fish on the floodplain are then already concentrated and are easily fished. The amount of fish landed during each flood regime varies from one year to another and throughout the river basin. Catch is also a function of effort and productivity of the individual fishermen and the type of gear used.
The fish stocks of the Kilombero River Basin are self-regulating. Recruitment, which is the accession of juveniles to a fishable stock is dependent on the parent population and on food supply, as well as fishing. The stocks are long-lived species and the biomass, which is the total amount of fish that is available in a body of water at any one particular time, is influenced greatly by the extent and duration of floods.
Catch tends to vary with the level of effort and, hence, each level of effort is associated with a different equilibrium size. The catch is therefore a function of stock size and effort. This relationship is demonstrated by the following diagram.
Figure 1 Population equilibrium analysis
In Figure 1 at low effort E1, the population equilibrium is at P1 and as effort increases to higher levels, the catch curve shifts up and, hence, the equilibrium population size decreases as effort increases. With effort E3, for example, population decreases to P3.
Thus, the fishing mortality becomes a function of fishing effort and the size of the stock. For any given population size, higher effort is associated with larger catches and for any given level of effort, the larger the population, the larger the catch.
Based on Figure 1, the shape of the sustained yield curve will depend on the shape of the population equilibrium curve. If the equilibrium population size decreases as effort increases, catch will eventually always be larger than growth and, hence, the equilibrium population may fall to zero (Schaefer, 1957).
The growth of Morogoro Region has depended on the goods and services produced locally by the fisheries (Kilombero River basin) and agricultural sectors. Activities of these basic sectors provide the means of payment of raw materials, food and manufactured products not produced in the region. The two basic sectors also support the service activities, transportation and other public utilities which are predominantly local in productive scope and market areas.
Hence, the fluctuations of the fishing industry of the Kilombero River basin and those of the agricultural sector lead to fluctuations in local incomes which in turn also induce fluctuations in retail sales and other various service trades. Their fluctuations have had a multiplier effect like the growth of residential industries in the region's major towns.
In this paper an attempt is made to analyse the interrelations of the various sectors of the Morogoro Regional economy, as well as the spread of impulses originating from the basic sector to other sectors directly and indirectly.
Table 3 indicates the various sectors of the regional economy.
The Regional Multiplier is thus calculated for the year 1979 using the following formula:
The multiplier clearly indicates that the impulses are expansionary and inflationary in view of the fact that the region's increase in output and income does give rise to further induced spending as consumption rises due to a rise in regional income. Further expansion in production and income on the strength of the two basic sectors of agriculture and fisheries will still give rise to further induced spending because of excess without an obvious end to the process.
Commercial future exploitation of the basin is ideal in view of its high productivity, easy accessibility to the main commercial centres in the country, and a sufficiently developed infrastructure for the rural hinterland. Expansion of the traditional fishery of the Kilombero River basin could lead to increased income in the fisheries sector, could be an important source of scarce foreign exchange because of its potential for export of staple fish products to neighbouring countries and could reduce the growing unemployment problems experienced in the region.
Fish production, number of fishermen and canoes for the Kilombero floodplain for 1977 and 1978
|t/fisherman||t/canoe||Value of fish|
|1977||350||290||7 031||20||24||43 572||150.2||124.5|
|1978||332||250||2 042||6.1||8.2||13 911||55.6||41.9|
NOTE: US$ 1.00 = Tan.Sh. 8
Employment by sector, Morogoro Region (1979)
|Agriculture||419 609||219 609||200 000|
|Fisheries||3 000||1 000||200|
Construction, furniture and metals
|3 500||3 500||-|
|Manufacturing||14 975||5 000||9 975|
Transportation, communications and public utilities
|31 970||25 000||6 970|
|Wholesale and retail trade||6 500||6 500||-|
|Government administration||19 981||19 981||-|
|Total||499 535||280 590||218 945|
Source: Office of the Prime Minister, United Republic of Tanzania. A survey on the state of the economy of Morogoro Region up to 30 June 1980
At the present stage, it is not recommended that heavy capital investment be made in the fishery because of the uncertainty of the stock which fluctuates in accordance to the extent of the flooding. However, fish farming in the Kilombero area would be an ideal development alternative to increasing supply and, hence, promoting consumption in the region and the country.
The development of the Kilombero River basin fisheries requires tremendous efforts in dissemination of the findings of modern science and technology, expansion of education and training to improve the performance of operatives and the improvement of facilities for processing, marketing, handling and storage. Opportunities for selling high unit-value products to neighbouring countries could be envisaged and projects for improvement of traditional operations for serving the domestic market could be promoted.
The major constraint is the lack of finances and skills for developing the Kilombero floodplain fisheries. Even if such fisheries could be developed, the prevailing low purchasing power in the region holds back the transformation of potential demand into effective demand. Hence, effort is necessary to develop the means and incentives for both increased fish production and consumption. This may require bilateral and international assistance.
Unlike in developed countries, most of the responsibility for developing the fisheries is in the hands of the government. As is usually the case, rival claims of other branches of the economy often reduce the funds available to the fishery industry. To make up the shortages of capital and skills, bilateral and multilateral assistance is particularly required in the form of investment capital, provision of research and training facilities, as well as pilot stations. Such assistance, if supplemented with proper management and exploitation of the river basin, could expand the supply of fish in the region and in the country as a whole.
Anderson, L., 1977 The economics of fisheries management. Baltimore, Johns Hopkins University Press
FAO, 1978 Fisheries in the food economy. FFHC Basic Stud., (19)
Fox, P., 1976 Preliminary observations on fish communities of the Okavango Delta. Paper presented at the Symposium on the Okavango Delta and its future utilization. Gaborone, Botswana
Schaefer, M.B., 1957 Some considerations of population dynamics and economics in relation to the management of commercial marine fisheries. J.Fish.Res.Board Can., 14(5):669–81
Tanzania, 1980 Office of the Prime Minister, A survey on the state of the economy of Morogoro Region up to 30 June 1980. Dar-es-Salaam, Office of the Prime Minister
Welcomme, R.L., 1975 The fisheries ecology of African floodplains. CIFA Tech.Pap., (3):51 p. (issued also in French)
|Bona Bak Nyang||S.A. Gumaa|
|Director of Fisheries||Department of Zoology|
|Ministry of Wildlife, Conservation,||and||Faculty of Science|
|Fisheries and Tourism||University of Khartoum|
|The inland waters of southern Sudan cover more than 2 million ha. Fishery resources are underexploited. Fishing is a seasonal activity, and living conditions at fish camps are difficult. Most fish preservation is accomplished by sun-drying, and marketing is by “goods-exchange”.|
|The principal problems facing the fishery are lack of capital, communications, transport, fish storage and marketing facilities, fishing gears, and inefficient fish processing. However, the changing attitudes of the local peoples toward the fishing profession and with a multifaceted technical assistance programme for development of fisheries, the situation is now improving.|
|The Fisheries Cooperative Development Programme (FISHCOD) has as its cornerstone a Basic Services Package (BSP) which provides a variety of minimum services to maintain the fisherman's capacity to pursue his profession, including training in fishing and fish processing, provision of fishing gears, boats and consumer goods, improvement of health and hygiene at fishing camps, cooperatives, storage facilities and fish markets.|
|Problems thus far have been logistical and not conceptual, and understanding and acceptance of the programme has been increasing in all quarters.|
|Les ressources halieutiques des eaux intérieures du Soudan méridional, qui couvrent une superficie de plus de 2 millions d'hectares, sont sous-exploitées. La pêche y est saisonnière et se pratique dans des conditions difficiles. On se contente la plupart du temps, pour conserver le poisson, de le sécher au soleil, et la commercialisation s'effectue sur la base du troc.|
|Les principaux problèmes dans le secteur de la pêche sont le manque de capitaux, de moyens de communication et de transport et d'installations de stockage et de commercialisation du poisson, l'insuffisance du matériel de pêche et l'inefficacité des techniques de traitmenent du poisson. Toutefois, on constate actuellement une amélioration de la situation qui s'explique par le changement d'attitude des populations locales vis-à-vis de la profession de pêcheurs et par un programme polyvalent d'assistance technique pour le développement des pêcheries.|
|Le Programme de développement des coopératives de pêche (FISHCOD) s'appuie essentiellement sur un système de prestation de services de base destiné à permettre aux pêcheurs de continuer à exercer leur activité (formation professionnelle aux techniques de pêche et de traitement du poisson, fourniture d'engin de pêche, d'embarcations et de biens de consommation, amélioration des conditions de santé et d'hygiène sur les lieux de pêche et création de coopératives, d'installations de stockage et de marchés pour la commercialisation du poisson).|
|Les problèmes rencontrés jusqu'ici sont plutôt d'ordre logistique que conceptuel, et l'on constate que le programme est de mieux en mieux compris et accepté dans tous les secteurs de l'opinion.|
The White Nile has its southern most source in Burundi at the head of the Luvironzio River, 2 000 m above sea level. It later joins the River Kagera, the principal tributary from Lake Victoria (Figure 1), and emerges from it to pass through parts of two lakes, Kioga and Albert, before falling steeply down the Sudan plain. In the Sudan it partly feeds the swamps or ‘Sudd’ with about half its water content, the rest flowing smoothly down the basin where it meets the Blue Nile at Khartoum. This ‘Sudd’ region extends to about 500 km up to Malakal and forms an obstacle to navigation, irrigation, transportation and fishing.
The inland waters of the southern Sudan cover more than 2 million hectars, the fishery resources of which are, to a large extent, underexploited.
The rapid flow of the White Nile (which in some areas may reach 200 m3 sec.-1) renders fishing efforts futile in the main stream, especially with gear, such as gillnets and seine nets, thus leaving sheltered areas, such as lakes, smaller tributaries and the swamp, as the main centres for fishing activities. Besides the rapid water current, floating weeds (Eichhornia crassipes (Solms)) also form a serious obstacle to fishing and which at certain times of the year (July–August) may completely block the river.
The area where fishing activities are most prominent extends from Malakal to just beyond Bor at the Aliab valley. The main river varies in width all along its course and twines deeply all the way to Bor. The largest water bodies in the area where fishing activities are most extensive are the three lakes No, Jur (or Nuong) and Shambe. Other waters may be used but may not be as important commercially as these three sites. A confluence of several tributaries forms a stagnant water system just after Bor known as the Aliab valley.
In the southern part of the Sudan several methods for catching fish exist, some of which are used at the subsistence level while others are commercial. Subsistence fishing is either through the use of cast nets, traps, or quite commonly, spearing. Commercial fishing, on the other hand, has now been greatly modified through the introduction of modern gear, such as nylon gillnets and boats.
The Fisheries Department in the region has formulated a series of laws governing the type of fishing gear to be used, i.e., the types of nets, the twine and the meshes, also laws to prevent the use of poisons and explosives, as well as laws for quality inspection and marketing. At present commercial fishermen are using monofilment gillnets (nylon or otherwise) with a minimum mesh size of 3 in (76 mm).
A fish inspection ordinance applies to fishing camps in order to raise the standard quality of the fish for export. Most of these camps are run by town-based merchants with agents operating in the sites. Camp inspection is the duty of Fisheries officers which operate from long fibreglass boats with powerful outboard engines for quick and easy transport. Each officer-in-charge is fully responsible for the camps he visits and is fully authorized to decide on the quality of the fish and to see that the laws are abided.
In actual numbers certain species show highest abundance, however, the picture is reversed when wet weights are considered. All considered, it is the fish with large weights, e.g., Lates niloticus, Mormyrus caschive, Distichodus niloticus, Clarias, moon fish (Citharinus, Heterotis and Gymnarchus) that rank high in importance (Table 1).
The occurrence of all these species in confined waters, lakes and tributaries is only natural since, as stated earlier, the main Nile is too swift for fish to feed, breed and carry out other biological activities. These side waters are ideal breeding grounds where the spawn will find shallow waters and vegetation to adhere to, and the emergent larvae (which are too weak to swim) will find food and shelter. It is not before full metamorphosis, that the young fish will venture out of the lake. These lakes are very productive compared to the main stream with a much higher phyto- and zooplankton density. A few smaller water bodies, however, are not suitable for young fish because of adverse chemical conditions of the water.
Figure 1 The White Nile and its tributaries
Commercially-important species of fish of the River Nile
|Tilapia spp.||Lesser perch||20|
|Citharinus citharus||Moon fish||15|
|Distichodus niloticus||Rough cast fish||15|
|Lates niloticus||Nile perch||10|
|Heterotis niloticus||Thick-skinned fish||10|
|Gymnarchus spp.||Freshwater rat-tail||5|
Most of the commercially-important species have two breeding seasons, one in early April/May, and the other just before the flood in August/September. At the moment, however, the situation of overfishing is not serious and the waters still seem to contain adequate amounts for high production. The yield per hectare (at present) is well below that estimated earlier, which was 140 000–155 000 t/y for the southern waters and 165 000 t/y for all the other waters of the White Nile. The annual production at present ranges between 12 000 and 18 000 t/y, a typically underexploited situation. But we must bear in mind that about two thirds of the waters are still virgin due to their inaccessibility for reasons of natural barriers.
This problem may in future be partly solved by the construction of the “Jonglei Canal”, which will link Bor to Malakal and which, in its first phase, will drain 25 percent of the swamp, thus facilitating construction of roads or waterways to water bodies that were once inaccessible.
An important aspect determining the success of a fishery lies in the methods used for preserving and processing of the fish, getting them ready for utilization and marketing. In the southern region of the Sudan three main methods of fish processing can be found; salt-drying, sun-drying and smoking.
Owing to the harsh conditions in which fish camps are found it is impossible to utilize modern techniques such as freezing for processing and keeping of fish. Smoking of fish is not common since it is mainly practiced by smaller fishermen. Salt-drying, though the most efficient method, can only be implemented by large tradesmen at camps and cooperatives, since ‘salt’ remains a precious commodity in some desolate areas where commercial barges and steamers do not often pass. Sun-drying therefore remains the commonest though, not the most efficient, due to attack of fish by insects, etc., thus rendering the dry fish of a lower value commercially
Marketing of the dry fish is mainly through ‘goods-exchange’ with neighbouring countries like Zaire and Central Africa, where goods such as coffee, timber, tea and beer are taken in exchange. Rarely, however, is it sold for money since this will be followed by complicated procedures of currency exchange and customs.
At each fish camp fish above a certain size are split into two halves, salted and left to dry for a few days before being packed into large canvas bags. These are then piled by the ‘harbour’ where they will be ‘shipped’ to their final destinations. Commercial camps usually use commercial steamers and barges, while cooperative camps may use the latter, but also have their own barges.
Fish camps in the south of the Sudan do not function during the rainy season and with its onset, the fishermen usually sink their wooden boats and quit the camp, the main reason being that in damp conditions the fish will not dry well and often rot very quickly. With the recession of the flood (October/November) they come back, salvage the boats and resume their activities for the following 8–9 months.
The problems of fisheries in the White Nile basin are varied and complex. These have been related to lack of capital, lack of communications and transport, lack of storage and marketing facilities, lack of fishing gear and fish processing materials.
An extremely high rate of illiteracy among the fishermen population and lack of knowledge or modern fishing methods and gear have contributed to the stagnancy of fisheries activities. To top it all, the fishing profession has been until very recently, considered a despised activity by the local population.
Swift current of the river, seasonality of fishing and the presence of water hyacinth (Eichhornia crassipes) in the White Nile, particularly in the Sudd areas, have presented the fishermen with problems resulting in a low level of fishing operations. Long distances have caused problems of accessibility to market.
One serious problem faced by the fishermen is their inability to fish extensive areas of presumed high productivity simply because there is no access to isolated papyrus-locked lagoons, and there are no natural mounds or otherwise elevated areas on which the fishermen can establish their camps.
A word about the conditions of fishing camps may be in order here. Fishing camps are situated on mounds, ‘platforms built on clay and mud’, which become quite hard after they are dry. The floor level of these mounds is approximately 20 cm above the water level. Their size is sometimes as small as 100 m2. On these mounds the fishermen have their huts, racks for drying fish, shades for storing fish, cooking places, etc. The hygiene is not very satisfactory. Excrements of various origin can be seen anywhere. Fish offal and other garbage is heaped at the outskirts of the mound providing a good breeding ground for the flies. Mosquitoes are found in incredible numbers. No doubt then that malaria, diarrhea and other diseases are rampant with adverse effect on fish production.
The British Colonial Government's development policy was geared mainly toward the development of the cotton crop for export purposes. Fisheries was not a priority. That legacy of no priority to fisheries development was inherited and lasted long with us until recently when the Southern Region Government, with support from the Central Government and international and bilateral agencies, started to pay special attention to fisheries resources development.
The Department of Fisheries was established in the Southern Region Government to collect revenue through licensing and inspection fees. It also engaged in fish production by setting up fishing camps. The extension and development activities were ignored and for these reasons, it contributed little to the improvement of the fish industry.
Another problem has been the lack of any coordination between activities allied to fisheries and between the various agencies responsible for the fisheries development in the White Nile River basin.
During the last few years changes have been noticed in the attitudes of the Nilotic people toward the profession of fishing. One Nuer fisherman who appeared prosperous stated that in the 1977 November/December fishing season he brought 92 bales of fish to Juba. He commenced commercial operations in 1975. Whilst several of his brothers fished independently, financing the purchase of nylon twine for nets by the sale of cattle, he had gone to Omdurman as a labour migrant and saved £.Sd. 180. On his return home he built a small shop using indigenous materials and started commercial fishing, this activity eventually becoming his major source of capital. In 1976 he purchased a Yirol mahogany canoe for £.Sd. 260 and in 1977, a second for £.Sd. 255. In early 1978 he was employing four labourers using four nets from each canoe.
The Government also took many steps to reorganize the fisheries industry and launched a ten-point programme to attain this goal:
inviting bilateral and international agencies to assist the fisheries and related industries;
emphasizing the inclusion of fisheries activities as part of all development programmes launched in the area;
stimulating coordination of fisheries programmes;
training of fishermen;
cooperativization of fish production and marketing based on ethnic groups;
basic services package (BSP) approach to fishermen's requirements;
emphasis toward extension and development functions rather than revenue collection as regards staff of the Fisheries Department;
local self-sufficiency in fishing boats and local transport boats;
attention to health and hygiene in fishing camps;
intensive cooperative membership education.
The Fisheries Cooperative Development Programme (popularly known as FISHCOD), has been under implementation for about two years now. It is too early to assess its results, but the bright lining in the sky of darkness is already becoming visible.
Activities of the FISHCOD developed around the Regional Fisheries Training Centre established in Malakal in 1974 with the help of FAO/DANIDA. This Centre has been training the local fishermen in modern methods of fishing, fish processing, cooperative organization and the preparation and use of fishing gear. It has also graduated 30 boatbuilders. We have experienced some advantages in developing these two auxiliary industries together. The University of Juba runs a Faculty of Fisheries for training the high-level manpower for fisheries development.
Faced with the problem of enabling the graduates of the Fisheries Training Centre to carry out their profession after the graduation, they were advised to form fisheries and boatbuilding cooperative societies. One of each type has been established already and is functioning. Three more fish marketing cooperatives are scheduled to form during the next two years. The fisheries cooperatives are being formed on the basis of ethnic groups - Nuer, Shiluk and Dinka - one for each group with obvious advantages.
ILO, FAO, UNDP, DANIDA, the Executive Organ of the Jonglei Canal Commission, the Central and Regional Governments have all joined hands to assist the fisheries industry in the White Nile River basin. ILO/UNDP are running the Cooperative Fisheries and Boatbuilding Industry Project at Malakal. FAO/UNDP are implementing the Sudd Fisheries Development Project under the auspices of the Executive Organ of the Jonglei Development Commission at Bor. DANIDA financed the setting up of the Regional Fisheries Training Centre.
Another project supported by FAO/UNDP and launched in the area is the Integrated Rural Development in the Dinka area at Kongor. Activities for fisheries development are included in this programme also.
Planning and implementation of all these projects is coordinated through a Fisheries Development Coordination Council with representatives from all agencies concerned. The Council functions under the Executive Organ of the Jonglei Development Commission.
The Basic Services Package (BSP) approach is the cornerstone of all the FISHCOD programmes. BSP is conceived on the hypothesis that the fisherman should be provided a package of minimum services to enable him to maintain his interest, capacity and determination to pursue his profession. The BSP includes nine items:
training of fishermen in fishing, fish processing and preparation and use of fishing gear;
intensive cooperative membership education;
provision of fishing gear, e.g., boats, nets, salt, etc., on cash or hire-purchase credit;
provision of consumer goods on cash payment;
delivery of items under (3) and (4) and purchase of fish on cash payment at the fishing camps;
improvement of health and hygiene in fishing camps;
availability of fisheries and cooperative extension services at fishing camps;
provision of storage facilities at central points - Malakal, Shambe, Adok, Bor and Juba;
setting up fresh fish markets.
The responsibilities of the staff of the Fisheries Department are now focused toward fisheries extension and development activities rather than toward revenue collection and licensing. Cooperative Field Agents work hand in hand, with Fisheries Extension Agents to attain the goals of the FISHCOD programme as members of a team.
An important feature of the FISHCOD programme is developing the boatbuilding industry as an auxiliary of the fisheries development programme. Fishing canoes, boats and transport boats within the size range of 6 m to 12 m are being produced by the Boatbuilders Cooperative and sold to the Fisheries Cooperatives
As mentioned earlier, hygiene conditions in some fishing camps are horrible and must be improved. Although this is one of the services of BSP, not much has been done in this area.
The two pillars for the success of the FISHCOD programme are training in fisheries and education in cooperation. The programme lays due emphasis on both.