**7. Freshwater aquaculture in the Nile basin**

resources are pathogens, nutrients, trace metals, suspended solids, salts and oxygen demanding materials [25]. Siegel [26] reported that the nutrient base for aquaculture in Lake Manzalah is sewage carried by drains from as far away as Cairo, 140 km to the south. He added that untreated or poorly treated industrial wastes, heavy metals and other pollu‐ tants have been released into the Nile Delta drainage network and have been discharged, along with sewage and agriculture wastes, into the northern delta lakes and their associat‐ ed wetlands. Studies of sedimentary deposits in the southeastern sector of Lake Manzalah have detected different trace metal concentration. They have detected Hg (up to 822 ppb), Pb (up to 110 ppm), Zn (up to 635 ppm), Cu (up to 275 ppm), Cr (up to 215 ppm), Sn (up to 14 ppm) and Ag (up to 4.7 ppm). The results suggest that high concentrations of heavy metals in lake sediments may cause contamination in fish, especially bottom feeders in such environments [26]. This may be the case in the northern lakes, since all of them receive the

**Location Sampling HCB DDTs PCBs Γ-HCBs**

0.05-0.07

<DL-126

286-310

312-352

8.6-12.1

25-53 7-21

166-181

390-430

270-330

581-700

<DL-20

3-26 1-11

1993 0.03-0.18 0.10-0.56 18-48 0.37-1.57

26-55

Cairo 1993 <0.001 0.08-0.12 3-640

Rosetta Branch 1998 1-77 0.2-99 5-161

Damietta Branch 1988 <DL-93 90-102

Rosetta 95-97 197-217 83-97

Damietta 95-97 195-240 109-128

Delta- Egypt "Modified from [27]" <DL: below detection limit

92-93 0.84-2.28

**Table 5.** Concentrations (ng/l) of HCB, DDT's, PCB's and lindane in freshwaters from different locations of the Nile

Although both agricultural drainages and sewage discharges into the lake environments may be considered as sources of nutrient that can compensate the nutrients reduction in the Nile water after the construction of Aswan High Dam (AHD), these discharges have different pollutants, such as organochlorine compounds, which are not only harmful to the fisheries but also to the consumers of fish. In his study, [27] noted that the use of organochlorine insecticides in Egypt began in the 1950's and was extensively used until 1981 to protect crops from insects, disease fungi and weeds, to remove undesired vegetation and for domestic household use in

sewage discharges of major cities.

362 Biodiversity - The Dynamic Balance of the Planet

*River Nile*

*Nile Estuaries*

*Coastal Lakes*

Lake Manzala

Freshwater aquaculture activities in the Nile basin countries depend on the following main factors:

**1.** The status of fish as a main food source according to the customs of the local populations

The existence of a market demand for specific fish living in the local river and lake waters

The economic value of these activities for the private sector compared with other projects

This is clearly demonstrated by the estimation of aquaculture production within the Nile basin countries (Table 6). Although Lake Victoria produces almost 25% of the freshwater fish catch in Africa, the aquaculture productivity of countries sharing the basin of Lake Victoria is very limited. This could be due to the lack of interest of the private sector in developing aquaculture activities, since the Lake production easily satisfies local and international market demand. In Uganda the number of ponds totals 6200, covering a total area of 124.6 ha. In some of these ponds yields of about 10,000 kg ha-1 y-1 were recorded. The most widely distributed species are mirror carp and various tilapia species. However, since the Nile perch is the most popular fish for export, there is little interest in developing aquaculture. It is expected that future expansion in freshwater farming in this part of the Nile basin is promising, especially when the fish stock at Lake Victoria become overexploited.

Although freshwater aquaculture was not commercially practiced in Sudan until 1990, the population density increase and local market demands have encouraged large scale aquacul‐ ture of freshwater fish, especially Tilapia species. The main demand comes from the capital Khartoum, where population density is rising, with growing interest in tilapia fish as an alternative source of animal protein [3].

In Egypt, where water conservation is becoming the highest priority, the reutilization of drainage water from other activities has assisted private sector investment at aquaculture activities in general and freshwater fish farms in particular. This has been spurred by the Egyptian tradition of consuming fish as an essential food item. The local market demand for fish has increased tremendously during the last three decades due to population growth.


**Table 6.** National aquaculture production in the countries of the Nile Basin [29], [30]

Consequently, the price of captured fish has risen, assisted further by the degradation of the natural fisheries. The result was that fish moved out of the affordable range for poor people. The high price of fish was remedied by freshwater aquaculture, which is a very well-known practice in Egypt since 1930. Although records were not available at that time on the size of production, the FAO statistical services sector was able to establish records of the Egyptian fisheries and aquaculture beginning in 1950. These records indicate that the total fish catch from aquaculture has linearly increased up to 539,748 tons year -1 in 2005 (Figure 6). This quantity represents not only aquaculture freshwater fish but also brackish and marine cultured ones. Data suggests that >60% of this quantity consists of freshwater fishes, mainly Tilapia species.

are critically important in sustaining food security. However, this is not the case for the upstream countries of the Nile River basin, where, although the great lakes have abundant fish production, there is a lot of concern about malnutrition of the populations surrounding the basin. An example is provided by Lake Victoria which supports Africa's largest fishery. Its most valuable product is the Nile perch, much of which is exported. This has given rise to arguments claiming a direct linear relationship between perch exports and disturbingly high rate of malnutrition along the lake's shore [32]. This state of affairs is mainly due to the foreign fish processing companies that control the fish exports, and the high demand on the Nile perch especially in the EU countries. With such high demands for Nile perch, the value of the fisheries has risen considerably. In 1983, there were 12,041 boats operating on the lake. By 2004, there were 51,712 boats and 153,066 fishermen. Of the 1433 landing sites identified in 2004 along the lake shores, just 20% of the population had communal lavatory facilities, 4% were served by electricity and 6% were served by potable water supply [32]. The authors have concluded that, Policy options can include targeting health care specifically at the lake's communities. They also added that local organizations such as LVFO (Lake Victoria Fishery Organization), should translate the largest inland fishery benefit into discernible positive impact on the ground. That

0

1950

1955

1960

1965

1970

**Figure 6.** Aquaculture fish production in Egypt and its Economic value during the period 1950-2005 [14]

Aquaculture Value (US\$ 1000)

1975

1980

**Year**

1985

1990

1995

2000

2005

The Nile Fishes and Fisheries http://dx.doi.org/10.5772/57381 365

200000

400000

600000

**Tons/Year**

800000

1000000

means positive economic return has to be reflected on fishermen families.

The Ugandan portion of Lake Victoria fish is among the highest revenue foreign exchange earner for non-traditional exports. In fact, the fish exports registered unprecedented growth in earnings, coming second after coffee exports in 2001. Its proportional contribution to export earnings rose from 5% in 1994 to 17% in 2001. It is estimated that fish exports in 2001 were in the order of 28,000 metric tons, with a value of approximately US\$ 78 million. That estimate is

During the last two decades, and due to the reutilization of drainage water, the salinity in these water bodies has increased, leaving them brackish. These changes in water salinity are paralleled by changes in the cultured fish species. In fact, most of the fish farms responded to changes in water salinity by turning from Tilapia to carp fish farms and then to grey mullet. The total income of produced fish from aquaculture in Egypt is estimated at 971,846 \* 103 US \$ per year (Figure 6), according to the available estimate of 2005 [14]. Based on these figures it is estimated that the supply of fish per capita has increased from 7 kg year -1 in 1990 to 15 kg year-1 in 2003. In fact, Egypt is not only the leading country in the Nile River basin in freshwater aquaculture (Table 6), but also the first amongst the Mediterranean countries and the Arab world [31], [29], [3], [13], [14].

### **8. Economic value of freshwater fisheries of the Nile basin**

There is no doubt that freshwater fisheries provide an essential supply of animal protein to large parts of the developing world. At national, community and family levels these systems

**Figure 6.** Aquaculture fish production in Egypt and its Economic value during the period 1950-2005 [14]

Consequently, the price of captured fish has risen, assisted further by the degradation of the natural fisheries. The result was that fish moved out of the affordable range for poor people. The high price of fish was remedied by freshwater aquaculture, which is a very well-known practice in Egypt since 1930. Although records were not available at that time on the size of production, the FAO statistical services sector was able to establish records of the Egyptian fisheries and aquaculture beginning in 1950. These records indicate that the total fish catch from aquaculture has linearly increased up to 539,748 tons year -1 in 2005 (Figure 6). This quantity represents not only aquaculture freshwater fish but also brackish and marine cultured ones. Data suggests that >60% of this quantity consists of freshwater fishes, mainly Tilapia

**Table 6.** National aquaculture production in the countries of the Nile Basin [29], [30]

**Country 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 - 2007 Burundi** 25 24 25 30 50 50 55 55 50 10 200 **DR Congo** 723 759 760 700 700 730 700 750 750 750 2970 **Eritrea** - - - - - - - - - - - **Ethiopia** - 1 33 36 36 22 28 33 55 85 - **Egypt** 45000 50000 55000 55916 877 54195 45380 46887 45473 53302 635516 **Kenya** 126 251 603 698 722 749 763 813 893 500 4240 **Rwanda** 64 38 44 164 58 53 53 50 49 50 4038 **Sudan** 43 45 100 234 203 200 200 200 1000 1000 1950 **Tanzania** 35 37 375 375 400 350 200 150 200 200 10 **Uganda** 38 34 42 52 63 77 87 179 194 210 51110

During the last two decades, and due to the reutilization of drainage water, the salinity in these water bodies has increased, leaving them brackish. These changes in water salinity are paralleled by changes in the cultured fish species. In fact, most of the fish farms responded to changes in water salinity by turning from Tilapia to carp fish farms and then to grey mullet. The total income of produced fish from aquaculture in Egypt is estimated at 971,846 \* 103

\$ per year (Figure 6), according to the available estimate of 2005 [14]. Based on these figures it is estimated that the supply of fish per capita has increased from 7 kg year -1 in 1990 to 15 kg year-1 in 2003. In fact, Egypt is not only the leading country in the Nile River basin in freshwater aquaculture (Table 6), but also the first amongst the Mediterranean countries and the Arab

There is no doubt that freshwater fisheries provide an essential supply of animal protein to large parts of the developing world. At national, community and family levels these systems

**8. Economic value of freshwater fisheries of the Nile basin**

US

species.

world [31], [29], [3], [13], [14].

364 Biodiversity - The Dynamic Balance of the Planet

are critically important in sustaining food security. However, this is not the case for the upstream countries of the Nile River basin, where, although the great lakes have abundant fish production, there is a lot of concern about malnutrition of the populations surrounding the basin. An example is provided by Lake Victoria which supports Africa's largest fishery. Its most valuable product is the Nile perch, much of which is exported. This has given rise to arguments claiming a direct linear relationship between perch exports and disturbingly high rate of malnutrition along the lake's shore [32]. This state of affairs is mainly due to the foreign fish processing companies that control the fish exports, and the high demand on the Nile perch especially in the EU countries. With such high demands for Nile perch, the value of the fisheries has risen considerably. In 1983, there were 12,041 boats operating on the lake. By 2004, there were 51,712 boats and 153,066 fishermen. Of the 1433 landing sites identified in 2004 along the lake shores, just 20% of the population had communal lavatory facilities, 4% were served by electricity and 6% were served by potable water supply [32]. The authors have concluded that, Policy options can include targeting health care specifically at the lake's communities. They also added that local organizations such as LVFO (Lake Victoria Fishery Organization), should translate the largest inland fishery benefit into discernible positive impact on the ground. That means positive economic return has to be reflected on fishermen families.

The Ugandan portion of Lake Victoria fish is among the highest revenue foreign exchange earner for non-traditional exports. In fact, the fish exports registered unprecedented growth in earnings, coming second after coffee exports in 2001. Its proportional contribution to export earnings rose from 5% in 1994 to 17% in 2001. It is estimated that fish exports in 2001 were in the order of 28,000 metric tons, with a value of approximately US\$ 78 million. That estimate is

Fishing industry is also important for the livelihoods of over 65,000 fishermen and other people employed full-time in related activities (estimated at some 300,000 men). The fish industry in Egypt also produces fish powder (from non-edible fish) of about 543 tons to be used as nutritive

The Nile Fishes and Fisheries http://dx.doi.org/10.5772/57381 367

Without exception, the freshwater fisheries in the Nile basin countries are under severe and constantly stressful conditions. The Nile fisheries have continued to deteriorate despite its impressive freshwater resources and the many efforts by national and regional institutions with national and international support. This decline is mainly due to the rapid increase in population densities surrounding the water bodies of the Nile basin, which has negatively influenced the water quality of these basins and their fisheries. In addition, overexploitation of the fish resources has advantaged non-commercial and invasive species in their competition with native and economically valuable ones. The lack of regulatory fishing plans and man‐ agement policy in most of the Nile basin fisheries has also added complexity to any future strategic plans to safeguard such valuable resources. In order to manage this important sector

**9. Future of freshwater fish production of the Nile basin**

**•** Make appropriate information data available to guide decision makers

**•** Control the use and dumping of Pesticides residuals in the Nile basin

**•** Promote sustainable practices with the help of scientific knowledge.

**•** Investigate and improve the socio-economic status of fishermen.

of governments and NGO's to disseminate this information.

degraded natural fisheries of the Nile basin.

**•** Enforce laws and sustainable management of fisheries resources and the fish habitat.

**•** Provide adequate financial resources and human capacity to implement fisheries program.

**•** Regulate fishing gear and practices that may otherwise damage fish stocks and habitat.

The poverty of many of the diverse populations living along the Nile basin remains a barrier to the implementation of concepts of natural resources conservation, despite the many efforts

Faced with a continuing large gap between global supply and demand for fish protein, with critical shortage in some regions, aquaculture is widely regarded as having a crucial role to play in meeting global and regional food requirements over the next 20 years. Aquaculture can be a water efficient means of food production, and also brings wider resources manage‐ ment benefits. To this end, it is advisable that the Nile basin countries take advantage of the existing water resources and encourage the private sector in implementing aquaculture activities as an actual and future alternative of animal protein and as a substitute for the

food additives in poultry farms [13].

along the Nile basin there is a need to:

**Figure 7.** Growth trends in total fish production in Egypt (marine and freshwater catch) compared with aquaculture during the period 1950-2005 [14].

only for the Nile perch. Other estimates included Nile tilapia from other countries bordering the lake (Kenya and Tanzania). These account for a total catch of 110 metric tons. However, the difference in value is marked, since the Nile perch is exported to EU countries, while the other species and small size Nile perch are locally consumed or regionally exported at lower prices. Recent statistics on the annual total fish production of the three countries (Kenya, Tanzania and Uganda) from Lake Victoria is amounted to 960, 500 tones [30]

In Sudan freshwater fisheries contribute very little to the national economy, especially as the estimated fish consumption per capita is only 1.7 kg year -1. In general, the fishing industry in 2003 is estimated to have exported 1,629 tons of fish with a value of US\$ 533,000, while a quantity of 157 tons was imported for local consumption at a cost of US\$ 324,000. This means that the total earnings from fish production did not exceed US\$ 200,000 representing only 0.4% of the national GDP [13].

As previously highlighted, Egyptian fisheries, including both natural fisheries and aquacul‐ ture represent the largest producers of freshwater fishes within the Nile basin countries. This is mainly due to the rapid growth in freshwater aquaculture production, amounting to about 60% of the national total fish catch (Figure 7). Despite high fish production, the fishing industry plays a relatively minor direct role in the economy of Egypt. Nevertheless, domestic fish production makes a valuable contribution to the national food supply and to the traditional way of life, for which fish eating remains an important part. In addition, it is a significant source of food for the tourist industry.

Fishing industry is also important for the livelihoods of over 65,000 fishermen and other people employed full-time in related activities (estimated at some 300,000 men). The fish industry in Egypt also produces fish powder (from non-edible fish) of about 543 tons to be used as nutritive food additives in poultry farms [13].
