According to the database developed by DMRIF with TCP/ERT/2251, there are now 90 artificial reservoirs (no natural inland water bodies) in Eritrea, out of which 53 have a known area. Their total area amounts to 733 ha (Table A in Annex). The average depth of these 53 reservoirs is 6.0 meters. According to this average figure, the area of the 32 reservoirs for which there are data on capacity but not area can be estimated. This gives another 123 ha (Table B in Annex). The total available freshwater area is then 856 ha for 85 reservoirs.
Figure 1.: Breakdown of the main purposes of Eritrean reservoirs (number and area of reservoirs)
Most of the reservoirs are used for irrigation purposes (Figure 1), but those used for water supply, though only 4 in number, represent more than 35% of the total area. For those whose main purpose is unknown, it is most likely that their basic use would be irrigation. The major constraint induced by these primary uses is that aquaculture/fisheries would always be a second purpose with all the potential problems such as a drying in years of drought, or the impossibility to use organic fertilization in reservoirs aimed at human water consumption.
Concerning altitude, most of the reservoirs are situated in the highlands. More than 70% of the area is situated beyond 1800 m, and more than 55% beyond 2200 m (Figure 2). This has implications for water temperature and consequently on the yields that could be expected if reservoirs are stocked with warm water species such as Tilapia and Clarias.
Figure 2: Breakdown of the altitude of Eritrean reservoirs (number and area of reservoirs)
An estimate of air and water temperatures as a function of altitude has been done for Ethiopia, and one can reasonably estimate that it would be valid for Eritrea. However, most of the reservoirs in Eritrea are small, and their average water temperature should be between the calculated air and water temperatures (lesser heat storage capacity).
The temperature estimate, according to Figure 3, would be 17–21°C for reservoirs above 2200 m (1), 19–23°C for reservoirs between 1800 and 2200 m (2), and 23–25°C (and up to 30°C) for reservoirs below 1800 m (3).
Figure 3: Relationship between altitude, air and water temperature, and estimation of water temperature in Eritrean water bodies (1 > 2200 m, 1800< 2<2200 m, 3<1800 m)
Eleven reservoirs were visited during the mission (Beleza, Adi Sheka, Elabered 1 to 7, May Nefhi and Himbirti). They represent 345 ha out of a total of 856, and can thus provide a good idea of what Eritrean reservoirs are like in general. Most of the reservoirs have compacted earth dams, but the largest ones have either masonry or concrete dams.
Eritrean reservoirs are filled by temporary rivers and streams during the rainy season (mainly in July), and the water is then stocked for one year. A certain amount of these reservoirs dry up before the next rainy season, though exact details are not available except for those visited by the mission.
Water quality
Although no technical analysis material was available, the general aspect of impounded water and observation of aquatic life provide good indications of the suitability of reservoirs for aquaculture and/or fisheries and allows a rough estimate of the fish productivity. Findings are summarized in Table 1.
| Reservoir | Area (ha) | approx. water temp. | Mineral turbidity | Phytoplankton | Aquatic weeds | Shallow areas | Risk of drying | Risk of oxygen drop | General quality | Expectable yield (kg/ha/yr) |
| Beleza | 12 | 22 | - | ++ | ++ | ++ | ++ | - | + | 200 |
| Adi Sheka | 80 | 22 | - | -/++ | - | + | - | + | - | 100 |
| Elabered 1 | 15 | 25 | ++ | - | - | - | - | - | - | 150 |
| Elabered 2 | 0.5 | 27 | ++ | - | - | - | ? | ? | - | 150 |
| Elabered 3 | 5 | 27 | - | +++ | + | +++ | - | - | +++ | 500 |
| Elabered 4 | 1.5 | 27 | - | ++ | - | + | - | - | ++ | 350 |
| Elabered 5 | 2 | 27 | - | +++ | + | + | - | - | ++ | 400 |
| Elabered 6 | 1 | 27 | - | +++ | ++ | + | - | - | ++ | 500 |
| Elabered 7 | 0.5 | 27 | - | ++ | ++ | + | ++ | - | ++ | 350 |
| May Nefhi | 220 | ? | +++ | -/+++ | - | - | - | +++ | - | <100 |
| Himbirti | 5 | 20 | - | ++ | +++ | +++ | - | - | ++ | 300 |
Table 1 : Evaluation of the quality for fish culture and/or fisheries of 11 Eritrean reservoirs (-: low, +: moderate, + +: high, + + +: very high)
The best apparent conditions occur in Elabered 3 to 7 reservoirs, where the phytoplantonic activity is quite good and the temperature of the water relatively high. Shallow areas, which are suitable for fish breeding and feeding, occur mainly in relatively small reservoirs. Also, temperatures in highland reservoirs are moderate, which lowers their potential productivity, even when the conditions of phytoplankton, weeds and depth are suitable (Beleza and Himbirti reservoirs).
In the three largest reservoirs, the water quality seems poor mainly because of a high turbidity and an absence of shallow areas (May Nefhi, Elabered 1), or because of a lack of appropriate nutrients (Adi Sheka). At May Nefhi and Adi Sheka, heavy algae blooms were observed close to the banks, which may cause very low oxygen levels during the night. At May Nefhi, the mission team was told that these blooms could cover the whole area of the lake. Such a condition presumably is unsuitable for fish culture/fisheries because of the oxygen reduction risk, although it might be possible that the introduction of fish would allow the control of blooms (but not the turbidity anyway).
Another aspect that can only be supposed is that as all the reservoirs are filled with runoff water. They must then become very silty by the end of the rainy season, and this must notably delay the start of the biological activity. A slight lack of food would then occur during a period to be determined, which could affect the overall productivity of these water bodies. The issue of water quality should obviously be evaluated and monitored in a more scientific way, but the general appreciation from the field trips is that potential is quite limited, unfortunately mostly in the largest reservoirs.
There are no indigenous fish in the Eritrean reservoirs, so all the present fish have been stocked at one time or another. Still, it is not clear whether there are fish or not in many of the water bodies.
The reservoirs which were built by the Italians were generally stocked with common carp (Cyprinus carpio), catfish (Clarias spp.) and sometimes eel (Anguilla anguilla). The latter have no doubt long since disappeared, as they cannot breed in fresh water. Catfish and common carp have in some cases persisted, for example in Elabered reservoirs where they seem to breed and grow normally. In Adi Sheka reservoir, catfish reportedly were present but disappeared after the destruction of the dam during the war. However, as catfishes can live under extreme conditions they most probably are still present since the reservoir never dried completely. Their presence would then be unknown because no real fishing activity occurs at this location.
| Reservoirs | Species | Area (ha) | Tentative yield (kg/ha/yr) | Tentative production (kg/yr) |
| Adi Sheka | Tilapia, Crucian carp (?), Catfish (?) | 80 | 100 | 8,000 |
| Elabered 1 | Common carp, Catfish | 15 | 150 | 2,250 |
| Elabered 2 | Common carp, Catfish | 0.5 | 150 | 75 |
| Elabered 3 | Common carp, Catfish | 5 | 500 | 2,500 |
| Elabered 4 | Common carp, Catfish | 1.5 | 350 | 525 |
| Elabered 5 | Common carp, Catfish | 2 | 400 | 800 |
| Elabered 6 | Common carp, Catfish | 1 | 500 | 500 |
| Elabered 7 | Common carp, Catfish | 0.5 | 350 | 175 |
| TOTAL | 14,825 |
Table 2: Estimation of fish productivity in Eritrean reservoirs
The second possible origins for fish in the reservoirs are the introductions made by the Ethiopian Fisheries Department in 1989. As far as is known two reservoirs were stocked at that time with Crucian carp (Carassius spp.) and Tilapia zilli :
Beleza reservoir with some 1000 fish for 12 ha;
Adi Sheka reservoir with some 50 fish for 80 ha.
Though the introduction was successful in Beleza there are apparently no fish at present. The reservoir has probably dried since 1989. In Adi Sheka, despite the very low number of fish introduced, Tilapia zilli are still present and are known to breed. The presence of Crucian carp is possible but unknown. For May Nefhi reservoir the situation is unclear. No fish are known to have been introduced, but small fish of an unidentified species have been reported by one source. Other informants claim that no fish has ever been noticed in this reservoir, however. The reservoirs where presence of fish is documented are summarized in Table 2.
The production estimate of the Eritrean reservoirs where fish are now present is around 15 tons. It is now interesting to see to what extent that production is being exploited.
There is now only one professional inland fisher in Eritrea, who operates in Elabered reservoirs. He is 72 years old and has been fishing there for over 35 years.1 This veteran operator angles for catfish with a single hook (No 7) line on a 4–5 m bamboo pole.2 He uses carp fillets as a bait, and catches the carps with bread. Catching up to 8 catfish per day, his total daily average can be estimated around 3 kg. As he fishes an average of 5 days per week, his annual catch should be 260 × 3 = 780 kg.
Catfish is sold in fillets, at prices of 1 EBirr for a small fillet (100–150 g) and 2 EBirr for a big fillet (300 g). This makes for an average price of 7 EBirr/kg fillet. The filletting yield of catfish being around 50%, the fisher's daily earning should be 3 × 50% × 7 = 10.5 EBirr, and the yearly earning would then be 10.5 × 260 = 2730 EBirr.
The assumed costs would be :
50 hooks and 50 m line (1 EBirr/pc, 1 EBirr/m)
78 l cooking oil (1 l oil for 5 kg fillets, 5.50 EBirr/l)
The yearly costs would then be 50 + 50 + 78 × 5.50 = 429 EBirr, which leaves a fair net income of approximately 2300 EBirr.
Subsistence fisheries have also been noticed in Elabered 1 and Adi Sheka. The method in Elabered 1 is unknown, and in Adi Sheka it is quite rudimentary (enclosing tilapia in shallow bays and then catching them by hands). In Adi Sheka, people know how to fish with hooks and used to do so for catfish before the destruction of the dam. They now state that hooks are no longer available.
At all events, the catch of these subsistence fisheries must be very low, and the total inland catch in Eritrea is probably 1 ton or less per year.
The only freshwater products sold in Eritrea are the fried catfish fillets in Elabered. The price is fairly high (7 ETB/kg), but the village where the fish is sold is close to Elabered State Farm and it is likely that customers, many of whom are employees of the farm, have an above average purchasing power.
It must be noted that in this area, though common carp are present and the fisher is able to catch them, none is being consumed except by the fisher himself. Other people find it too bony.
1 Some years ago two Nigerians, now deceased, used to fish at Elabered as well.
In Adi Sheka reservoir, tilapia is caught for occasional self-consumption, and prepared fried (when oil is available), in soup or in “wott” (the traditional national food). Catfish was also eaten before the destruction of the dam.
Though the market for freshwater fish almost does not exist, it seems that the most acceptable fish are catfish and tilapia. As common carp is at least 30 % of the existing production potential, the real exploitable production potential would then be around 10 tons per year of catfish and tilapia.
As noted before, Eritrea has 856 ha of inland water bodies. In order to make a gross estimation of the production potential, the following assumptions were made:
water bodies whose average depth is below 4 meters were considered as having a high risk of drying, and consequently were not taken into account;
extrapolating from estimates for the reservoirs that have been visited, annual productivity was estimated at 200 kg/ha/yr for reservoirs over 2200 m, 300 kg between 1800 and 2200 m, and 400 kg below 1800 m.
Based on these assumptions, the total production that could be expected from Eritrean inland fisheries is more or less of 150 tons per year (see Table A and B in Annex). Yet this figure must be immediately qualified as perhaps too optimistic, since:
the reservoirs which dry may be more numerous than estimated;
even for those which don't dry completely, the area and the subsequent production might be slightly reduced at the end of the dry season, and moreover a risk of altered water quality (oxygen) would exist during the warm months as the water content might be reduced, with more concentrated nutrients and a warmer temperature; and
for the largest reservoirs visited (May Nefhi, Adi Sheka, Elabered 1), the on-the-spot productivity estimates are far below those in the estimation pattern (the total production for these three reservoirs could be around 32 t instead of 66 t).
In light of all these reasons, it seems fair to say that 150 t should be considered as a maximum and that a more realistic figure would be an inland fisheries potential of 100 t per year.
The freshwater fish market would be limited to remote rural areas or small towns where sea fish is not available, because it is very unlikely that people used to the high quality, tasty fish from Massawa would accept to eat freshwater fish. It is generally difficult to people used to seafish to turn to freshwater fish.
The commercial market for freshwater fish should be very limited. For example, as his income level is quite satisfactory, it is very surprising that the Elabered fisher has no competitors. Moreover, he practices self-limitation of his catches, though they are far below the potential of the place. It is then very likely that the market in this area is already saturated by some 3 kg of fish per day, even though conditions are quite favorable. Fish have been present in the area for a long time, and local purchasing power is beyond the average for rural areas because of the presence of the Elabered State Farm. In Adi Sheka, the fish are caught for self-consumption and sale of the catches has never occurred. It is likely that most people in rural areas could not in fact afford the expense of buying fish.
Taking all these points into account, it can reasonably be assumed that the main market for freshwater fish in Eritrea would be a subsistence market in the short term, and may become monetised only in the long term.
Another aspect of the situation is the availability of fishing gear. The fisher in Elabered stated that gear was only available in Asmara, but that now it was even impossible to find fishing line there. The villagers in Adi Sheka stated that hooks were no longer available. This is quite understandable due to the extreme narrowness of the freshwater fishing gear market. Even if there was a development of freshwater fishing activities, it is extremely unlikely that the market would develop itself enough to induce private trade of fishing gear, especially in remote rural areas. In any development plan for inland fisheries, the issue of availability of fishing gear should be studied seriously.
It should be borne in mind that the potentials estimated above are biological potentials. To get the maximum economic and social profitability from the exploitation of fish stocks, it is generally recommended that production should be 70% of the potential. Moreover, as the quantities considered are quite limited, it is not suitable to use “heavy” equipment such as gillnets and boats. The use of “light” equipment like hooks and lines operated from the shore (or castnets) would limit the catches to a comparable figure, thus allowing this maximum economic and social profitability.
The production figures allowed would then be 7 t/yr for the currently stocked lakes, and 70 t/yr in the hypothesis of the stocking and exploitation of all available water bodies.
Relying more or less on the figures available for the existing inland fisher, one could assume that 1 kg fish caught with hook and line would cost 0.2 EBirr to the producer, and that it could be sold at around 3 EBirr (direct sale), leaving a 2.8 EBirr/kg profit (from which labour should be remunerated). If the producer fishes for self-consumption, a non-monetary profit of 2.8 EBirr (saving on potential expenses) could be assumed.
According to these figures, the exploitation of the existing resources would generate a profit of 19,600 EBirr at the national level, and the exploitation of the potential resources would generate 196,000 EBirr. In the case of the latter, however, some expenses will have to be incurred for the stocking of reservoirs. Assuming that the transfer of a fingerling caught in the existing stocked reservoirs to an empty one would cost 0.2 EBirr, the stocking of 500 ha would require 500,000 fingerlings and cost 100,000 EBirr. This would be a medium-long term action, as the collection of fingerlings could only start very slowly due to the lack of important breeding stocks. For subsequent years, a recurrent cost of 20,000 EBirr/year could be expected (restocking of reservoirs where accidents have occurred, such as drying or oxygen failure). The recurrent profit at the national level would then be of 176,000 EBirr/yr.
It must be remembered that these figures do not take into account the costs of administrative staff, research equipment, etc., which may be involved in an inland fisheries monitoring activity. It is also to be noted that both the need of fingerlings and the expected profit do not take into account the establishment of a breeding station (high investment costs, but mostly high recurrent costs).
Also, it would also be necessary for the development to occur by itself, without any need of training, subsidised inputs, marketing facilities, and so on, with the administrative action being limited to the stocking and monitoring of reservoirs. Fulfillment of these conditions is questionable, as most of the rural people in Eritrea have exceedingly limited to nil experience with the consumption or catching of fish.
It is furthermore necessary that all the potential would be caught, otherwise the costs of stocking and monitoring activities would be too high compared to the income generated.
This is why the most reasonable solution for the moment could be to deal with the existing fish stocks, to see if an improvement of their exploitation would be possible by low cost actions such as making fishing gear available on a commercial basis. If these experiences fail, it would mean that in the actual socio-economic context of Eritrea there is no real interest and/or market for freshwater fishes. In that case, the cost of an extension/information campaign will have to be evaluated in view of the expected returns.
Ultimately it is important to bear in mind that inland fisheries development in Eritrea would have very limited benefits even in case of total success, and that many unfavorable market and other socio-economic conditions could well affect the outcome of such a development.
The same factors that pose obstacles to the development of inland fisheries in Eritrea must also be carefully considered when assessing the potential for inland aquaculture development. Questions of water shortage and quality especially loom as serious concerns, and make the prospect of classical pen farming unlikely. New technologies are emerging particularly in Isreal for intensive aquaculture in enclosed systems adapted to the needs of arid zones. These are based on either ground water or desalinated water and have very low water replenishment requirements as they are recirculating. However, the technological and capital inputs for these systems are extremely high and it is very doubtful that they would be appropriate to serve the needs of Eritrea at the present time.
