COUNTRY FILES (Contd.)

NASSER/NUBIA RESERVOIR
(International water)

(See detailed ref. in Entz, 1984)

Geographical data (see Fig. 8)
Location:	Egypt (Nasser); Sudan (Nubia) - 20° 27'-23° 58'N; 30° 35'–33° 15'E
Altitude:	183 m at USL; 170–175 m mean
Dam height:	111 m
Date closed:	May 1964; working lake level reached Sept. 1979
Surface area:	6 850 km² at USL
	6 216 km² at 180 m lake level (5 072 km² in Egypt; 1 144 km² in Sudan)
	3 057 km² at 160 m lake level (2 497 km² in Egypt; 560 km² in Sudan)
Depth:	mean at 180 m lake level:	25.2 m
	at 160 m lake level:	21.6 m
	max. at 180 m lake level:	130 m
	at 160 m lake level:	110 m
Volume:	mean at 180 m lake level:	65.9 km³
	(55.6 km³ in Egypt; 10.3 km³ in Sudan)
	max. at 180 m lake level:	156.9 km³
	(132.4 km³ in Egypt; 24.5 km³ in Sudan)
Length:	max. at 180 m lake level:	496 km
	mean at 160 m lake level:	430 km
Width:	max. at 180 m lake level:	60.0 km
	mean at 180 m lake level:	12.5 km (total lake)
		18.5 km (only Nasser)
	mean at 160 m lake level:	7.5 km (total lake)
		8.9 km (only Nasser)
Shoreline:	at 180 m lake level:	9 250 km
	at 160 m lake level:	6 027 km
Annual fluctuation in level: 7–10 m
Catchment area above High Dam: 2 400 000 km²
Mean inflow:	84.0 km³/yr; 2 662 m³/sec
Suspended solids:	1–10 mg/l (low water); 2–10 g/l (flood); inflow: 134 × 10⁶ t/yr
Displacement time:	2 years
Major inflowing river:	Nile
Outflowing river:	Nile

Specific references: Ali, 1984; Entz, 1984; Latif, 1984; Marshall, 1984.

Physical and chemical data
Surface temperature:
	16–32° C (23.9° C mean); 16–18° C during winter period
Conductivity:	190–300 μS/cm; 260 μS/cm; (210–230 μS/cm mean)
Dissolved solids:	175–200 mg/l (185 mean)
pH:	6.8–9.0; 7.1–9.4
Oxygen:	winter: 6.7–11 (surface); 5.4–8.7 (bottom)
	summer: 4.9–10 (surface); 0 (bottom)
Ionic composition:		mg/l
	Na	8.2–27.8
	K	1.9–8.0
	Ca	14.3–27.5
	Mg	4.5–12.5
	HCO₃	70–160
	Cl	2.96–9.83
	SO₄	5–10.8
	SiO₂	12.45–17.18
	NO₃
	surf.	0.001–1.25
	bottom	0.04–1.27
	PO₄-P	0.10–0.17

Fisheries data
No. of fish species:
	In Nasser Reservoir:
	53 in 16 families (Latif, 1984). See list, Table 4 (p.186). Oreochromis niloticus and O. galilaea are the major fish landed, comprising 95% (1978) of the total fresh, and 75% (1978) of the total salted fish landed (Latif, 1984).
	In Nubia Reservoir:
	43 in 16 families (Ali, 1984). See list, Table 4.

Total annual catch and effort:

	Total catch (t)		No.of fishermen	No.of boats
Year	Nasser	Nubia	(Nasser only)	(Nasser only)
1964	500
1966	749		600	200
1967	1 415		1 050	350
1968	2 663		1 500	500
1969	4 071		1 815	599
1970	5 618	198	2 466	816
1971	6 716	144	3 822	1 039
1972	8 545	228	4 540	1 135
1973	10 693	424	-	-
1974	12 257	268	-	-
1975	14 725	295	-	-
1976	15 971	285	-	2 000
1977	18 406	249	-	-
1978	22 587	204	5 964	1 962
1979	26 995	355	-	-
1980	30 316	628	-	-
1981	33 933	625	-	-
1982	-		9 000	-

Fig. 8. NASSER/NUBIA RESERVOIR
(FAO/UNDP, 1975)

Potential annual yield:

Nasser Reservoir:
earlier estimates based on MEI: 19 000 t/yr
30 000 t/yr (Sadek, 1984)
35 000 t/yr in 1982 (Entz, 1984)
30 kg/ha/yr (Sadek, 1984)
78 kg/ha/yr (Entz, 1984)

Nubia Reservoir:
5 000 t/yr (Ali, 1984)
5 100 t/yr (51 kg/ha/yr) (Henderson, 1975)

Table 8. LIST OF FISH SPECIES FOR NASSER/NUBIA RESERVOIR
(adapted from Latif, 1984 and Ali, 1984)

	Family	Species	Nasser ^a	Nubia ^b
1.	PROTOPTERIDAE	Protopterus aethiopicus	+	+
2.	POLYPTERIDAE	Polypterus bichir	+
		P. spp.		+
3.	MORMYRIDAE	Mormyrops anguilloidos	+	+
		Petrocephalus bane	+	+
		Marcusenius isidori	+
		M. spp.		+
		Gnathonemus cyprinoides	+	+
		Mormyrus kannume	+	+
		M. caschive	+	+
		Hyperopisus bebe	+	+
4.	GYMNARCHIDAE	Gymnarchus niloticus	+
5.	CHARACIDAE	Hydrocynus forskalii	+	+
		H. lineatus	+
		H. brevis	+
		Alestes nurse	+	+
		A. baremose	+	+
		A. dentex	+	+
6.	DISTICHODONTIDAE	Distichodus niloticus	+	+
		D. rostratus		+
		D. engycephalus		+
7.	CITHARINIDAE	Citharinus citharus	+	+
		C. latus	+
8.	CYPRINIDAE	Chelaethiops bibie	+
		Raiamas niloticus	+
		R. loati	+
		Labeo forskalii	+
		L. niloticus	+	+
		L. coubie	+	+
		L. horie	+	+
		Discognathus vinciguerrae	+
		Barbus werneri	+
		B. perince	+
		B. neglectus	+
		B. anema	+
		B. bynni		+
9.	CLARIDAE	Clarias anguillaris	+	+
		C. Lazera	+	+
		Heterobranchus bidorsalie		+
10.	SCHILBEIDAE	Eutropius niloticus	+	+
		Schilbe mystus	+	+
		S. uranoscopus		+
		Siluranodon auritus	+
11.	BAGRIDAE	Bagrus bayad	+	+
		B. docmac	+	+
		Chrysichthys auratus	+	+
		C. rueppelli	+
		Clarotes laticeps	+	+
		Auchenoglanis biscutatus	+
		A. occidentalis	+	+
		A. spp.		+
12.	MOCHOKIDAE	Synodontis schall	+	+
		S. serratus	+	+
		S. clarias	+
		S. batensoda		+
		S. khartoumensis		+
		Mochocus niloticus	+
		Chiloglanis niloticus	+
13.	MALAPTERURIDAE	Malapterurus electricus	+	+
14.	CICHLIDAE	Oreochromis niloticus	+	+
		O. galilaea	+	+
15.	CENTROPOMIDAE	Lates niloticus	+	+
16.	TETRODONTIDAE	Tetraodon fahaka	+	+
17.	OSTEOGLOSSIDAE	Heterotis niloticus		+
			53	43

^a Latif, 1984
^b Ali, 1984 (Note: Nubia data are for 1967–1979)

ROSEIRES RESERVOIR

Geographical data (Welcomme, 1972, 1979)
Location:	Sudan - 11° 40'N; 34° 23'E. See Figs. 2 and 6 (p.177).
Date closed:	1966
Surface area:	290 km²
Depth:	68 m (max); 10 m (mean)
Volume:	3 km³
Max. length:	75 km
Major inflowing rivers:	Blue Nile
Outflowing river:	Blue Nile
Annual fluctuation in water level: 13 m

Fisheries data
No. of fishermen:	70–100 (1975)
Total annual catch:
	300–500 t (1975) (Henderson, 1975);
	2 250 t (1976),
	1 800 t (1982),
	1 500 t (1984) (George et al., 1985).
Potential annual yield:
	1 700 t (58 kg/ha/yr) (Henderson, 1975)

SENNAR RESERVOIR

Geographical data (Welcomme, 1972, 1979; Henderson, 1975)
Location:	Sudan - 13° 46'N; 33° 36'E. See Figs. 2 and 6 (p.177).
Altitude:	422 m
Date closed:	1925
Surface area:	140–160 km²
Depth:	26 m (max); 6.5 (mean)
Volume:	0.93 × 10⁹ m³ (CSTR, 1982)
Major inflowing river:	Blue Nile
Outflowing river:	Blue Nile
Annual fluctuation in level: 17 m

Fisheries data
No. of boats:	50 (1975)
Total annual catch:
	1 000 t (1975) (Henderson, 1975)
	1 400 t (1982),
	1 100 t (1984) (George et al., 1985; FAO, 1982).
Potential annual yield:
	1 100 t (71 kg/ha/yr) (Henderson, 1975)

7. BIBLIOGRAPHY

Ali, 1984
Bailey, 1987
Balarin, 1986; 1988
Blache & Miton, 1962
Boulenger, 1907
Brook & Rzoska, 1954
Burgis, 1987
Carleton & Pena, 1982
Coche, 1983
CSTR, 1982
Dumont, 1984
Entz, 1984
Europa Publs., 1986
FAO, 1982; 1983a,b
FAO/UNDP, 1975
FAO/WB, 1976
George, 1975; 1976
George et al., 1985
Green, 1987
Hefny, 1982
Henderson, 1975
Huet, 1959
Ibrahim, 1984
Kapetsky & Petr, 1984
Krishnamurthy, 1981
Latif, 1984
Marshall, 1984
Osro, 1986
Sadek, 1984
Sandon, 1950
Talling, 1957
Welcomme, 1972; 1979; 1985
Yousif, 1985

TUNISIA

1. GEOGRAPHY AND CLIMATE

Tunisia has an area of 15 536 km². The Atlas Mountains dominate the topography of the northern part of the country, rising to a maximum elevation of 1 544 m asl. The south is mainly desert (40% of the total land area). The interior is hot and dry, while the coastal zone is more moderate. The north generally receives adequate rainfall. Due to low runoff and high salinities water quantity and quality limit irrigation agriculture in most parts of the country.

2. HYDROGRAPHY

2.1 Lakes

Kelbia (100 km²) and Sidi Mansour (35 km²) are the two largest low-salinity lakes. There are several others of less than 1.0 km². A number of salt lakes and marshes occur in the country, some of large basin size (i.e., Chott Djerid, 4 580 km²; Chott Fedjadj, 570 km²; Sabkhet Sidi El Hani, 360 km²). The term “chott” or “sebkha” defines a non-permanent water body (swamp or lake), submitted to the occurrence of seasonal precipitations.

2.2 Rivers, Floodplains and Swamps

Four small river systems discharge into the Mediterranean Sea; the Oued Medjerda is the largest of these. Several landlocked rivers discharge into salt lakes. Total national runoff is only 2.5 km³/year of rainfall of 33 km³/year (90% is lost as evaporation).

2.3 Reservoirs

There are 14 large dams/reservoirs with a combined area of over 176 km². The two largest are Bourguiba-Sidi Saad (90 km²) and Sidi Salem (43 km²). The total impounded volume is 1.451 km³ or 58% of total annual runoff. There are some 15 small earthen dams which store irrigation and potable water. Combined area is circa 2.0 km². There are also small reservoirs associated with nine principal oases, with a combined area of 0.03 km².

2.4 Coastal Lagoons

There are seven important coastal lagoons with a combined surface area of 550 km²; the largest are Bibane (230 km²), Bizerte (150 km²) and Ichekeul (100 km²).

2.5 Aquaculture

No data available on aquaculture ponds or production centres.

3. FISHERY PRODUCTION/POTENTIAL

3.1 Fish production and per caput supply (see Table 1)

3.2 Inland catch range and potential yield (see Table 2)

Table 1. FISH PRODUCTION - Tunisia, 1970–1987

		Nominal Production (including exports) (t) ²				Nominal Consumer Supply (including exports) (kg/person)
Year	Population '000 ¹	Inland capture ⁷	Aquaculture ³	Marine capture ⁶	Total	Inland capture	Aquaculture ³	Marine capture	Total
1970	5 127	100	- ⁴	24 300	24 400	0.02	-	4.8	4.8
1971	5 220	100	-	27 400	27 500	0.02	-	5.3	5.3
1972	5 315	100	-	28 000	28 100	0.02	-	5.3	5.3
1973	5 412	800	-	31 000	31 800	0.15	-	5.7	5.7
1974	5 511	301	-	42 350	42 651	0.05	-	7.7	7.7
1975	5 611	0	-	31 686	31 686	0	-	5.6	5.6
1976	5 759	0	-	34 923	34 923	0	-	6.1	6.1
1977	5 911	0	-	38 441	38 441	0	-	6.5	6.5
1978	6 067	0	-	54 600	54 600	0	-	9.0	9.0
1979	6 228	0	-	58 778	58 778	0	-	9.4	9.4
1980	6 392	0	-	60 073	60 073	0	-	9.4	9.4
1981	6 524	0	-	57 376	57 376	0	-	8.8	8.8
1982	6 659	0	139 ⁵	62 708	62 847	0	0.02	9.4	9.4
1983	6 797	0	186 ⁵	67 051	67 237	0	0.03	9.9	9.9
1984	6 937	0	116 ⁵	74 871	74 987	0	0.02	10.8	10.8
1985	7 081	0	147 ⁵	88 908	89 055	0	0.02	12.6	12.6
1986	7 237	0	182 ⁵	92 618	92 800	0	0.02	12.8	12.8
1987	7 396	0	212 ⁵	99 169	99 381	0	0.03	13.4	13.4

¹ Source: FAO
² Source: FAO Fisheries Department FISHDAB
³ included in “Inland capture” if not specified.
⁴ - = data not available.
⁵ fresh, brackish and marine water (Vincke, 1989, pers.comm.).
⁶ from 1980 to 1983, marine exports were as follows: 1980–6 368 t; 1981–6 679 t; 1982–5 479 t; 1983–7 167 t. The export figure for 1969 was 1 555 t.
⁷ Lagoons capture is included in marine capture.

Table 2. INLAND CATCH RANGE
(no potential yield figures available)

Water body	Period	Annual catch range (t)
Lake Besbessia	1969	1.3
Lake Kelbia	1966; 1968; 1972	191.7; 18.5; 0.6
Bir M'Chergua Reservoir	1980	3.5
Mellegue Reservoir	1970; 1981	2.4; 4.4
Nebhana Reservoir	1980	8.9
Bibane Lagoon	1970; 1981	269; 440
Bizerte Lagoon	1973; 1981	24.5; 101
Ghar El Melh Lagoon	1967; 1981	21.4; 64
Ichkeul Lagoon	1970; 1981	60.6; 195
Khenis Lagoon	1971; 1981	7; 10.4
Tunis Lagoon	1970; 1981	472.8; 490.5

No information available for:
Lake Sidi Mansour; Mejerda River; Reservoirs Abdel Monam, Ben Metir, Bezirk, Bou Heurtma, Bourguiba-Sidi Saad, Chiba, Gdir El Goulla, Kasseb, Lakhmess, Masri, Mlaabi, Nacherine, Sidi Salem and Tahouna; Bou Grara Lagoon

Total annual yield (including lagoons): 900–1 350 t
Potential annual yield: no data available.

Fig. 1. MAP OF TUNISIA

4. STATE OF THE FISHERY

4.1 Yield

Since the mid-1950's total inland catch has generally remained between 900 and 1 500 t/yr. Most of this is derived from the lagoons. A significant production is obtained from aquaculture (finfish and shellfish). Aquaculture production (t) by species, from 1982 to 1987, is given below (Vincke, 1989, pers. comm.).

Species	1982	1983	1984	1985	1986	1987
Dicentrarchus labrax	-	-	2	15	30	40
Sparus aurata	-	-	15	5	20	25
Mugilidae	-	-	-	5	10	12
Crassostrea gigas	12	19	4	12	20	25
Mytilus galloprovincialis	127	167	95	110	102	110
Total	139	186	116	147	182	212

4.2 Factors influencing yield

Lakes and reservoirs suffer from prior rainfall runoff in some years (see, for example, the trend in catches from Lake Kelbia which is mainly the result of declining rainfall).

4.3 Future development possibilities

Certainly reservoir fisheries are at a low state of development and offer good possibilities for expansion. Lagoons also do not appear to be particularly heavily exploited. Extensive aquaculture practices could increase lagoon yields.

5. KEY BIBLIOGRAPHY

Lemoalle, 1987 (Coastal Lagoons)

6. WATER BODIES DIRECTORY

Lakes (Chotts)
Besbessia	Kelbia	Sidi Mansour

Rivers
Medjerda

Reservoirs
Abdel Monam	Chiba	Mlaabi
Ben Metir	Gdir El Goulla	Nacherine
Bezirk	Kasseb	Nebhana
Bir M'Chergua	Lakhmess	Sidi Salem
Bou Heurtma	Masri	Tahouna
Bourguiba - Sidi Saad	Mellegue

Lagoons
Bibane	Ichkeul (= Tindja)
Bizerte (= Menzel, Abderahmen)	Khenis (= Monastir)
Bou Grara	Tunis (= Goulette)
Ghar El Melh

LAKE BESBESSIA (Chott)

Geographical data
Location:	Tunisia

Fisheries data
Total annual catch:	1.3 t (1969)

LAKE KELBIA (Chott)

Geographical data
Location:	Tunisia - 35°35'N; 10°8'E (see Fig. 2
Surface area:	0–100 km² (highly variable; can dry up)
Depth:	2.25 m (max); 0.75 m (mean); 0 (min).

Physical and chemical data
Salinity:	highly variable: 1–80 ‰
Dissolved solids:	4.0–70 g/l

Fisheries data
Total annual catch:
	Year	Total catch (t)
	1961	115.7
	1966	191.7
	1968	18.5
	1969	82.1
	1970	10.4
	1971	41.8
	1972	0.6

LAKE SIDI MANSOUR (Chott)

Geographical data
Location:	Tunisia - 34°14'N; 9°30'E
Surface area:	up to 35 km², but can dry up completely for periods of several years.
Inflowing rivers:	Baiache, Segui, Belkhire

Physical and chemical data
Temperature:	3–24° C
Total dissolved solids:	1 200 mg/l

MEDJERDA RIVER
(International water)

Geographical data
Source:	Algeria
Total length:	305 km (80 km in Algeria; 225 km in Tunisia)
Countries traversed:	Algeria, Tunisia
Major tributaries:	Mellegue
Discharges to:	Mediterranean Sea - 37°6'N; 10°14'E
Special features:	Mellegue Reservoir on Mellegue tributary in Tunisia

ABDEL MONAM RESERVOIR

Geographical data
Location:	Tunisia
Surface area:	0.31 km² at normal level
Depth:	3.5 m (mean) at normal level
Volume:	1.1 × 10⁶ m³ at normal level
Outflowing river:	Abdel Monam

Physical and chemical data
Total dissolved solids: 900 mg/l

BEN METIR RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	440 m at USL
Dam height:	60 m
Date closed:	1954
Surface area:	3.50 km² at USL; 2.90 km² at normal level
Depth:	20.9 m (mean) at USL; 19.7 m (mean) at normal level
Volume:	73 × 10⁶ m³ at USL; 57.2 × 10⁶ m³ at normal level
Outflowing river:	El Lil

Physical and chemical data
Total dissolved solids:	1 000 mg/l

BEZIRK RESERVOIR

Geographical data
Location:	Tunisia
Dam height:	22 m
Date closed:	1959
Surface area:	1.02 km² at normal level
Depth:	5.9 m at normal level
Volume:	6 × 10⁶ m³ at normal level
Outflowing river:	Bezirk

Physical and chemical data
Total dissolved solids:	1 600 mg/l

BIR M'CHERGUA RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	122.50 m at normal level
Dam height:	43 m
Date closed:	1971
Surface area:	7.05 km² at normal level
Volume:	0.130 m³ at USL
Outflowing river:	Meliane

Fisheries data
Total annual catch:	3.5 t (1980, 4 months)

BOU HEURTMA RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	228 m at USL; 221 m at normal level
Date closed:	1976
Surface area:	8.94 km² at normal level
Depth:	13.1 m (mean) at normal level
Volume:	117.5 × 10⁶ m³ at normal level
Annual fluctuation in level: 2–3 m
Major inflowing rivers: Guezala, El Lil

BOURGUIBA-SIDI SAAD RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	282 m at normal level
Date closed:	February 1982
Surface area:	90 km² at normal level
Depth:	40 m (max) at normal level; 2.2 m (mean) at normal level
Volume:	0.200 m³ at normal level
Major inflowing rivers:	El Hateb, El Hadjed
Outflowing river:	Zeroud

CHIBA RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	78 m at USL
Dam height:	26 m
Date closed:	1963
Surface area:	2.72 km² at normal level
Depth:	1.5 m (mean) at normal level
Volume:	4 × 10⁶ m³ at normal level
Outflowing river:	Chiba

Physical and chemical data
Total dissolved solids:	1 500 mg/l

GDIR EL GOULLA RESERVOIR

Geographical data
Location:	Tunisia
Dam height:	27 m
Date closed:	1968
Surface area:	0.07 km² at normal level
Depth:	40.0 m (mean) at normal level
Volume:	2.8 × 10⁶ m³ at normal level

KASSEB RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	292 m at USL
Dam height:	57.6 m
Date closed:	1969
Surface area:	4.37 km² at USL
Depth:	57 m (max) at USL; 18.7 m (mean) at USL
Volume:	81.9 × 10⁶ m³ at USL
Annual fluctuation in level: 5 m
Outflowing river:	Kasseb

LAKHMESS RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	517 m at normal level
Dam height:	32 m
Date closed:	1966
Surface area:	1.02 km² at normal level
Depth:	7.8 m (mean) at normal level
Volume:	14.6 × 10⁶ m³ at USL; 8.0 × 10⁶ m³ at normal level
Outflowing river:	Lakhmess

MASRI RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	161 m at normal level
Dam height:	38 m
Date closed:	1965
Surface area:	0.95 km² at normal level
Depth:	7.4 m (mean) at normal level
Volume:	7 × 10⁶ m³ at normal level

MELLEGUE RESERVOIR

Geographical data
Location:	Tunisia - 36° 19'N; 8° 42'E
Altitude:	270 m at USL (250 m, mean level)
Date closed:	1956
Surface area:	16.0 km² at USL
	14.72 km² at normal level
	7.705 km² at mean level
Depth:	45 m max at mean level
	65 m max at USL
	18.2 m (mean) at normal level
Volume:	267.7 × 10⁶ m³ at normal level
Outflowing river:	Mellegue

Physical and chemical data
Total dissolved solids:	1.0–2.5 g/l

Fisheries data
Total annual catch:
	Year	Tons
	1968	5.2
	1970	2.4
	1979	4.9
	1980	11.5
	1981	4.4

MLAABI RESERVOIR

Geographical data
Location:	Tunisia
Surface area:	0.98 km² at normal level
Depth:	3.6 m (mean) at normal level
Volume:	3.5 × 10⁶ m³ at normal level
Outflowing river:	Mlaabi

Physical and chemical data
Total dissolved solids:	900 mg/l

NACHERINE RESERVOIR

Geographical data
Location:	Tunisia
Dam height:	14 m
Date closed:	1962
Surface area:	0.151 km² at normal level
Depth:	9 m (max) at USL; 2.50 m (max) at mean level;
	2.6 m (mean) at normal level
Volume:	0.4 × 10⁶ m³ at normal level
Outflowing river:	Nacherine

Physical and chemical data
Total dissolved solids:	2 800 mg/l

NEBHANA RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	230 m at USL
Dam height:	62 m
Date closed:	1968
Surface area:	5.32 km² at USL
Depth:	16.2 m (mean) at USL
Volume:	86 × 10⁶ m³ at USL
Outflowing river:	Nebhana

Physical and chemical data
Temperature:	12.8° C
Total dissolved solids:	1 000 mg/l

Fisheries data
Total annual catch:	8.9 t (1980, 3 months)

SIDI SALEM RESERVOIR

Geographical data
Location:	Tunisia
Altitude:	110 m at USL
Dam height:	57 m
Surface area:	43.00 km² at normal level
Depth:	12.9 m (mean) at normal level
Volume:	0.555 km³ at normal level
Outflowing river:	Mdjerda

TAHOUNA RESERVOIR

Geographical data
Location:	Tunisia
Surface area:	0.125 km² at normal level
Depth:	7.2 m (mean) at normal level
Volume:	0.9 × 10⁶ m³ at normal level
Outflowing river:	Tahouna

Fig. 2. COASTAL LAGOONS AND SEBKHAS OF NORTH TUNISIA
(after Lemoalle, 1987)

EL BIBANE LAGOON

(all data, except “Total annual catch, 1961–81” from Lemoalle, 1987)

Geographical data
Location:	Tunisia - 33° 15'N; 11° 15'E (see Fig. 3)
Surface area:	230 km²
Depth:	6.8 m (max); 4 m (mean)
Volume:	934 × 10⁶ m³

Physical and chemical data
Surface temperature:
	max. August: 28–30°C
	min. January: 6–11 °C
Salinity:	(in 1981–82, central part)
	end of summer: 45 ‰;
	end of winter: 42 to 43.5 ‰
Alkalinity:	2.5–2.8 meq/l
Ionic composition:	close to sea water

Fisheries data
No. of fish species:	over 60 species, all marine; Sparus aurata, Diplodus annularis and Solea vulgaris = 60% of the catch.

Total annual catch:

Year	Tons	Year	Tons
1961	628.4	1971	246.2
1962	583.0	1972	255.1
1963	652.4	1973	288.1
1964	596.2	1974	235.5
1965	513.8	1975	46.8
1966	478.2	1976	385.0
1967	448.5	1977	335.0
1968	385.9	1978	523.6
1969	256.4	1981	440.5
1970	269.6	1980's mean 535 t/yr (23 kg/ha)

Fig. 3. EL BIBANE LAGOON
(after Lemoalle, 1987)

BIZERTE (= MENZEL, ABDERAHMEN) LAGOON

Geographical data
Location:	Tunisia - 37° 12'N; 9° 51'E (see Fig. 2)
Surface area:	150 km²
Depth:	15 m (max); 1.0 m (mean)
Max. length:	13 km
Max. width:	11 km
Major inflowing river:	Tindja Channel (outflow from Ichkeul Lagoon)
Outflow:	Bizerte Canal (8 km) to Mediterranean Sea.

Physical and chemical data
Surface temperature:	10–28.6°C (18.25° C annual mean)
Salinity:	27–39 ‰ (34.17 ‰ annual mean)

Fisheries data
Total annual catch:	Year	Tons
	1908	170
	1939	2 400
	1973	24.5
	1977	51
	1981	101.6
Aquaculture production:	(mussels)
	1964	92
	1976	70

BOU GRARA LAGOON

Geographical data
Location:	Tunisia - 33° 35'N; 10° 50'E
Surface area:	500 km² (subdivided by a causeway into a large western basin and a small eastern basin)
Depth:	10+ m (max); 3 m (mean)
Max. length:	27 km
Max. width:	22 km
Outflow:	restricted passageways to Mediterranean Sea.

Physical and chemical data
Surface temperature:	11.5–34° C
Salinity:	37.50–39.35 ‰

GHAR EL MELH LAGOON

(all data, except “Total annual catch, 1961–81”, from Lemoalle, 1987)

Geographical data
Location:	Tunisia - 37° 10'N; 10°10'E (see Fig. 4)
Surface area:	26 km²
Total length:	7 km
Max. width:	4.5 km
Depth:	2 m (max); 1.0 m (mean)
Major inflowing river:
	lateral flooding of Medjerda (formerly); at present several small streams and drainage channels.
Outflow:	short canal to Mediterranean Sea.

Physical and chemical data
Salinity:	in winter: 25–37 ‰
	in summer: 39–46 ‰
Surface temperature:	18.5°C (mean); 27.4°C (max); 9.7°C (min).
Ionic composition:	same as sea water.

Fisheries data
No. of fish species:	12 small stationary species;
	32 migratory marine species.
No. of fishermen:	420
Total annual catch:
	Year	Tons	Year	Tons
	1961	57.7	1971	16.0
	1962	119.0	1972	11.3
	1963	162.6	1973	63.5
	1967	21.4	1974	50.2
	1968	21.5	1975	46.9
	1969	20.2	1976	44.8
	1970	15.3	1978	64.8
			1981	64.1
	1980'5, current mean: 62 ± 20 t/yr
	(Mugils over 50%; Anguilla, 15%; Dicentrarchus, 8%)

Fig. 4. GHAR EL MELH LAGOON
(Lemoalle, 1987)

ICHKEUL (= TINDJA) LAGOON

(all data, except “Total annual catch, 1961–81” from Lemoalle, 1987)

Geographical data
Location:	Tunisia - 37° 17'N; 9° 40'E (see Fig. 2)
Surface area:	89 km² in summer; 100 km² in winter
Catchment area:	2 200 km²
Total length:	14 km
Max. width:	5 to 6 km; plus swamp extensions in winter
Depth:	2 m (max); 0.90 m (mean)
Major inflowing rivers:	Sejnane (44%) and Joumine (38%); total inflow, including smaller streams: 271 × 10⁶ m³/yr. In summer, sea water inflow through Tindja Channel.
Outflow:	Tindja Channel to Bizerte Lagoon (5 km downstream) in winter.

Physical and chemical data
Surface temperature:	9.5–29.5° C (18.2° C annual mean)
Salinity:	1–3 ‰ (end winter); 30–33 ‰ (end summer)

Fisheries data
No. of fish species:	mainly Mugils (68% of the catch), Anguilla (25%), Dicentrarchus labrax and Solea vulgaris
Total annual catch:
	Year	Tons	Year	Tons
	1961	19.3	1971	92.1
	1962	72.2	1972	92.8
	1963	129.8	1973	260.5
	1964	60.4	1974	173.0
	1965	86.4	1975	160.6
	1966	127.6	1976	115.7
	1967	57.6	1977	123.1
	1968	76.7	1978	132.0
	1969	22.2	1981	195.0
	1970	60.6
	1980's, current mean: 128 t/yr (13.5 kg/ha) with high variability.

KHENIS (= MONASTIR) LAGOON

(all data, except “Total annual catch, 1961–81” from Lemoalle, 1987)

Geographical data
Location:	Tunisia - 35° 45'N; 10° 45'E (see Fig. 5)
Surface area:	1.73 km²
Total length:	3 km
Max. width:	0.5 km
Depth:	2.00 m (max. in the channel); 0.5 m (mean central)
Special features:	an artificial lagoon created by damming shallow seabed in the South (in 1952).

Physical and chemical data
Surface temperature:	mean, in 1977–78: 12.8°C in January; 28°C in July
Salinity:	40 to 50 ‰
Oxygen (saturation):	60 to 130%

Fisheries data
No. of fish species: main catches: mugils, Sparidae
Total annual catch:
	Year	Tons
	1971	7.0
	1972	4.4
	1973	16.0
	1974	5.4
	1975	11.2
	1976	11.9
	1977	9.4
	1978	9.2
	1981	10.4
Production:	mean: 34 kg/ha/yr; since 1984 there is an important aquaculture production centre.

Fig. 5. MONASTIR LAGOON
(after Lemoalle, 1987)

TUNIS (= GOULETTE) LAGOON

(all data, except “Total annual catch, 1961–81” from Lemoalle, 1987)

Geographical data
Location:	Tunisia - 36° 50'N; 10° 10'E (see Fig. 6)
Surface area:	45 km² (bisected by a canal), decreasing
	North basin: 28 km²; outflow: Khereddine Channel
	South basin: 13 km²; outflow: South Channel
Depth:	3.60 m (max); l m (mean)

Physical and chemical data
Surface temperature:
	19.2°C (mean); 9°C (in winter); 30°C (in August)
Salinity:	North basin: 38 ‰ (winter 33, summer 43 ‰)
	South basin: 42 ‰ (winter 40, summer 45 ‰)
Special features:	highly eutrophic due to input of municipal sewage; high concentration of H₂S in sediments, mainly in north basin.

Fisheries data
Main fish species:	Mugilidae (mainly Mugil cephalus, chelon labrosus, Liza ramada) and Anguilla anguilla, for the migratory species; Aphanius fasciatus as stationary species.
Total annual catch:
	Year	Tons
	1961	496.6
	1962	582.0
	1963	357.2
	1964	364.2
	1965	313.0
	1966	408.7
	1967	535.6
	1968	432.6
	1969	606.9
	1970	472.8
	1971	546.7
	1972	531.3
	1973	946.7
	1974	651.1
	1975	465.7
	1976	379.7
	1977	580.5
	1978	700.0
	1981	490.5
	1980's, current mean: 500 t

Fig. 6. TUNIS LAGOON
(after Zaouali, 1987)

7. BIBLIOGRAPHY

Lemoalle, 1987
Zaouali, 1987

WEST SAHARA

1. GEOGRAPHY AND CLIMATE

The Saharawi (surface area of 178 999 km²) consists largely of desert plateau. The climate is hot and semi-arid. Most of the country is too arid for agriculture. There are large deposits of phosphate.

2. HYDROGRAPHY

2.1 Lakes

Although there are a number of lake basins, they are usually dry.

2.2 Rivers, Floodplains and Swamps

There are two river systems (the Uad el Fat and Uad Assag), but they infrequently contain water.

2.3 Reservoirs: None of significant size.

2.4 Coastal Lagoons: None of significant size.

2.5 Aquaculture: No aquaculture in West Sahara (Vincke, 1989, pers.comm.)

3. FISHERY PRODUCTION/POTENTIAL

3.1 Fish production and per caput supply (see Table 1)

3.2 Inland catch range and potential yield

No information available.

4. STATE OF THE FISHERY

4.1 Yield

No data available, but there seems to be no inland fishery activity.

4.2 Factors influencing yield

Extremely low rainfall.

4.3 Future development possibilities

Extremely limited. The construction of artificial coastal lagoons (for example at Bahia, de Rio de Oro) would create some additional potential.

5. KEY BIBLIOGRAPHY (none)

Table 1. FISH PRODUCTION AND PER CAPUT SUPPLY - West Sahara, 1970–1987

		Nominal Production (including exports) (t) ²				Nominal Consumer Supply (including exports) (kg/person)
Year	Population '000 ¹	Inland capture	Aquaculture ³	Marine capture	Total	Inland capture	No aquaculture	Marine capture ⁵	Total
1970	76	- ⁴		4 000	4 000	-		52.6	52.6
1971	84	-		4 000	4 000	-		47.6	47.6
1972	93	-		4 000	4 000	-		43.0	43.0
1973	102	-		4 000	4 000	-		39.2	39.2
1974	110	-		4 000	4 000	-		36.4	36.4
1975	117	-		4 000	4 000	-		34.2	34.2
1976	123	-		4 000	4 000	-		32.5	32.5
1977	126	-		4 000	4 000	-		31.7	31.7
1978	129	-		4 000	4 000	-		31.0	31.0
1979	132	0		0	0	0		0	0
1980	135	0		0	0	0		0	0
1981	139	0		0	0	0		0	0
1982	142	0		0	0	0		0	0
1983	147	0		0	0	0		0	0
1984	151	0		0	0	0		0	0
1985	155	0		0	0	0		0	0
1986	159	0		0	0	0		0	0
1987	164	0		0	0	0		0	0

¹ Source: FAO
² Source: FAO Fisheries Department FISHDAB
³ No aquaculture in West Sahara (Vincke, 1989, pers.comm.)
⁴ - = data not available.
⁵ Most of the fish being exported, the “nominal consumer supply” data for marine capture do not reflect the reality and are highly overestimated.

6. WATER BODIES DIRECTORY

No permanent water body.

Fig. 1. MAP OF WEST SAHARA