Scientific Names | Arabic or Syrian Names | English | French |
Fish | |||
Pleuronectidae | |||
Scophthalmus rhombus (L) | Sole | Brill | Barbu |
Psetta maxima (L) | Sole | Turbot | Turbot |
Solea vulgaris | Sole | Sole | Sole |
Mugilidae | |||
Mugil cephalus (L) | Buri | Common mullet | Mulet cabot |
Mugil auratus (Risso) | Buri | Gold mullet | Mulet doré |
Mugil chelo (Cuvier) | Buri | Thicklip grey mullet | Mulet lippu |
Mugil capito (Cuvier) | Buri | Thinlip grey mullet | Mulet porc |
Mugil saliens (Risso) | Buri | Leaping grey mullet | Mulet sauteur |
Carangidae | |||
Seriola dumerilii (Risso) | Intias | Yellow tail Amber jack | Sériole |
Serranidae | |||
Dicentrarchus labrax (L) | Ghanbar | Sea-bass | Loup, bar |
Sparidae | |||
Likhognathus mormyrus (L) | Faride | Striped sea-bream | Marbré |
Sparus auratus (L) | Ijaj | Gilthead sea-bream | Dorade |
Diplodus sargus (L) | Sargus | White sea-bream | Sar |
Pagellus erythrinus (L) | Jarbiden | Common pandora | Pageot common |
Crustaceans | |||
Penaeidae | |||
Penaeus kerathurus (Forskal) | Kreides, Gambero | Prawn | Caramote |
P. japonicus (Bate) | Kreides, Gambero | Prawn | Crevette japonaise |
P. semisulcatus (De Haan) | Kreides, Gambero | Prawn | Crevette Alexandrette |
Metapenaeus stebbingi (Nobili) | Kreides, Gambero | Prawn | Crevette Alexandrette |
(from FAO, 19801)
1. CHARACTERISTICS OF SOME TILAPIA SPECIES
Temp. range ° C Lethal limits optimum | Breeding 25 cm fish brood/brood year | Salinity % | ||||
Max. breeding | known max. | |||||
Mouth brooders | ||||||
S. spilurus | - | - | - | - | - | 42 |
S. niloticus | 11–42 | - | 500 | - | 29 | 42 |
S. mossambicus | 8–42 | 20–35 | - | 9 | 35 | 40 |
S. aureus | 8-? | - | - | - | - | 42 |
Generalized mouth brooders | 8–40 | 20–35 | 700 | 6–7 | - | - |
Nest guarders | ||||||
T. zillii | 7-? | - | 6 000 | - | 29 | 43 |
2. SUITABILITY OF TILAPIA SPECIES FOR MARINE RESEARCH (Peacock, 1979)
2.1 Species and site
The species tested during these experiments were the following:
Species | Fingerling source | Number imported |
T. zillii | Egypt, Kenya | 300, 100 |
S. niloticus | Kenya | 1 500 |
S. spilurus | Kenya | 520 |
S. aureus | Kenya | 500 |
Fingerlings were obtained at a weight ranging between 1 and 4 g. First, the acclimatization was gradual (5 % per day), in order to confirm salt water tolerance. Then, fingerlings were acclimated in bulk at 10 % and sometimes 20 % per day and transported to sea cages in batches of 100.
The site was Sharm Obhor, a deepwater creek 25 km north of Jeddah. The cages (holding 1 m3 of water) were hung from a 25 m2 raft moored in 20 m depth within 1 km of the mouth of the creek.
Sea temperatures range from 25 to 31°C, averaging 26–27°C from January to May and 28–29°C for the rest of the year.
Fingerlings were fed on trout fry feed up to 50 g whence they graduated to carp feed.
2.2 On-growing Sarotherodon niloticus
A total of 1 500 4-mg fingerlings were imported from Kenya, but a problematic journey reduced the number to 100 which were released in a sea cage after acclimatization. At the third month, a non-identified disease became apparent.
At the fourth month, the males weighed 55 g, the females 20 g. At the fifth month, the cage ruptured.
2.3 On-growing Sarotherodon spilurus
Although fingerlings suffered the same difficult journey experienced by S. niloticus, they survived markedly better (20 % survival after shipment to marine cages and losses by escape through meshes).
On a first trial, about 100 Spilurus fingerlings were released in a net-lined 1 m3 cage. The growth average rate was 1.7 % per day, compared with the 2.9 % achieved in fresh water at Roobab Farm in Kenya with male tilapia. It was suspected that poor feeding was responsible for these results. The fishes weighed around 250 g after 8 months of growth. Mortality, at a rate of 4.7 % per month, was low.
A second trial used a batch of Jeddah-bred fish initially weighing 0.9 mg. During the first five months, the growth rate was 2.7 % per day, which is very satisfactory. Mortality was low again (5.8 % per month). The growth rate dropped markedly as the fish approached 100 g, and again poor feeding is believed to be responsible.
2.4 On-growing S. aureus
The following results showed that S. aureus is not to be considered for salt-water rearing:
mortality after the flight bringing the fishes from Kenya
extensive mortality during salt-water acclimatization
sensibility to diseases
failure to breed satisfactorily.
2.5 On-growing Tilapia zillii
T. zillii from lake Qarun in Egypt were the first tilapia species imported and these adapted well to sea-cages, although they were affected by disease in saltwater aquaria. This species grows more slowly than the three previously described, whilst favouring a cheaper vegetarian diet.
Other trials were initiated by importing fingerlings from Kenya. Two trials were followed by lethal results during salt-water acclimatization. T. zillii are the most common salt-water adapted species in the Near East, but it is apparent that the purely freshwater strain from Kenya lacks the tolerance of Egyptian T. zillii.
2.6 Conclusions
On-growing certain Tilapia species in full-strength seawater is evidently not only feasible, but apparently capable of achieving results at least comparable with those of freshwater techniques. Among the species tested, Sarotherodon spilurus stood out as demonstrating a survival and growth performance that matches the requirements of aquaculture, Admittedly, these trials were of limited duration, occurring over one year with few batches of fish. Other species should not be rejected at this stage.
A combination of aspects of saltwater tolerance, satisfactory breeding characteristics and ease of handling present a very strong case for selecting S. spilurus for marine tilapia farming (which looks very promising).
3. PRELIMINARY OBSERVATIONS OF SOME ASPECTS OF BREEDING THE AFRICAN CICHLID SAROTHERODON SPILURUS (Osborne, 1979)
At an average temperature of 30°C, female Sarotherodon spilurus were found to breed every 9–14 days if the eggs or yolk sac fry were removed from the buccal cavity for in vitro incubation. A breeding unit of 15 females and 2 males produced 64 319 eggs and fry from 82 broods in 50 days of breeding, 1.64 broods per day; 48 000 eggs, 11 155 yolk sacs and 5 164 fry were obtained from 54, 17 and 9 broods respectively, an average of 857 eggs or 656 yolk sac fry or 574 fry per brood. The production was obtained in an area of 8 m2, out of which only 4 m2 were used by the breeding population.
A large incubator, with an incubation capacity of 10 000 eggs has been designed. Hatch rates over 90 percent were obtained by using this apparatus.
Prophylactic use of formalin at the rate of 1:25 000 a.i. prevented fungus growth on the eggs and contributed to the high hatch rates obtained.
Yolk-sac fry were successfully incubated in shallow, unaerated dishes, at stocking densities up to 1 000 fry/litre. Survival rates were over 95 percent.
4. SOME ASPECTS OF THE SALINITY TOLERANCES AND SUBSEQUENT GROWTH OF THREE TILAPIA SPECIES: SAROTHERODON AUREUS, S. SPILURUS AND T. ZILLII (Osborne, 1979)
4.1 Methods
Salinity shocks (10, 20, 30 or 40 per mille) were applied to:
Acclimatization to various salinities has been tested with various procedures (ranging from gradual acclimatization to 40 per mille sea-water over 4 days to direct transfer to seawater) with:
Growths of S. spilurus in three different salinities (2 per mille, 20 per mille, 40 per mille) were tested.
4.2 Results and conclusions
Although eggs survived abrupt transfer to higher salinities, hatchability was reduced as salinity increased, from 95.7 percent at 2 per mille, to 86.3 percent at 10 per mille, 72.2 percent at 20 per mille, 48.2 percent at 30 per mille and 29.2 percent at 40 per mille.
No yolk-sac larvae survived beyond day 5 at salinities higher than 20 per mille. In 2 and 10 per mille, 99 percent of yolk sac fry that successfully hatched survived to day 7.
Survival of fry during acclimatization is dependent on the first salinity change. At a day 1 salinity of 10 per mille, survival was uniformly over 98 percent, even if subsequently transferred abruptly from 10 to 40 per mille. Survival reduced to 66 percent, 1.3 percent and 0 percent for a day 1 salinity of 20, 30 and 40 per mille respectively.
It is recommended that the fastest acclimatization procedure be used for fry, i.e., 2–10–40 per mille in two days. There is no apparent benefit from slow, gradual acclimatization.
Juvenile S. spilurus exhibit the same tolerances and survivals as fry.
Growth and survival in brackish or full-strength seawater are higher than that found in freshwater. A growth coefficient of 2.49 percent/day (length) in 2 per mille and 3.12 and 3.09 percent/day in 20 to 40 per mille respectively, was found.
There was no significant difference in growth rates in 20 or 40 per mille.
The race of T. zillii imported from Kenya appears unable to tolerate full strength seawater. However, a population of T. zillii which differs morphologically has been noted. This population lives at salinities of 1–3 per mille and has a reduced salinity tolerance in marked contrast to populations found in Lake Qarun, Egypt.
S. aureus appears unsuitable for culture in full-strength seawater. The possibility of a disease with this stock cannot, however, be ruled out entirely. It has been, therefore, recommended that further trials be carried out with this species.
1. Purpose of Analysis
The purpose of looking into the costs and earnings of potential pond culture is to form an opinion as to whether or not pond culture has a possibility of becoming economically attractive as a commercial activity.
2. Management Scheme
Recent developments in southeast Asia and the Middle East indicate that semi-intensive culture of mullets in saltwater ponds may be commercially viable. Mullet production of 3 t/ha/year is reported, from 30 g to 500 g (Mugil capito) or 1 500 g (Mugil cephalus) in a two-year production cycle. Calculations will be made for two different farm sizes: 8 and 50 hectares.
The farm has two types of ponds, all about 2 ha in size. Fry is harvested from the wild and raised for 9 months in fry rearing ponds until a weight of 30 g, then transferred to production ponds for growth to market size.
Pumping station is calculated for a water change every 3 months.
3. Inputs
Excavation accounts for the major part of pond construction costs. Therefore, the costs of pond construction do not decrease markedly with the increase in size of the farm (assuming, as we have done, that the size of individual ponds remains about the same).
Because of the considerable investment, depreciation and interest occupy between 25 and 30 percent of annual cost for a farm under full operation.
Amongst the recurrent costs, feed (40%) and salaries account for the greater part.
4. Output
The production of 3 t of mullets per hectare (of production pond) per year, uses a feed consisting of 25–30% of proteins.
As part of the pond area is used for grow-out of fingerlings, the effective yield is about 5/ha of pond area every two years.
5. Returns
The revenue generated, under different assumptions of prices at the farm-gate, is shown at the bottom of Table 5. Comparing gross revenue and costs it appears that this type of corporate fish culture, for the local market, could be commercially possible in Syria.
The price of £S 12/kg at the farm-gate, may be considered the equivalent of a freshwater fish price (Tilapia). At present, a £S 15/kg price is a minimum production price from fisheries.
Table 1
POND CONSTRUCTION AND ASSOCIATED INVESTMENT
ITEM | UNIT | SP/UNIT | LIFETIME | 8 ha | 50 ha | ||||
No OF UNIT | VALUE | DEPRECIATION | No OF UNIT | VALUE | DEPRECIATION | ||||
Construction of ponds | 2 ha pond | 160 000 | 20 | 4 | 640 000 | 32 000 | 25 | 4000000 | 200 000 |
Pomping station | Unit | - | 8 | 1 | 150 000 | 13 500 | 1 | 500 000 | 62 500 |
Building | m2 | 2000 | 20 | 50 | 100 000 | 5000 | 400 | 800 000 | 40 000 |
Fisheries equipment | - | - | 5 | - | 50 000 | 10 000 | - | 100 000 | 20 000 |
Other equipment | - | - | 5 | - | 50 000 | 10 000 | - | 200 000 | 40 000 |
Subtotal | 990 000 | 70 500 | 5600000 | 362 500 | |||||
Miscellaneous | % | - | - | 99 000 | 7050 | 560 000 | 32 250 | ||
Subtotal | 108 9000 | 77 550 | 6160000 | 398 750 | |||||
Working capital (1,5 year) | 257 500 | 1605000 | |||||||
Total investment | 1346500 | 7 765000 |
Table 2
COST OF CONSTRUCTION OF A 2 HA POND
DYKES CONSTRUCTION
- | Two external dykes : 2 × 100 m × 16 m2 = 3200 m3 | |
- | " dykes : 2 × 200 m × 8 m2 = 3200 m3 | |
Total excatated and compacted = 6400 m3 × 20 S.P. = | 128 000 | |
Inlet facilities (part of canal, pipes) | 10 000 | |
Outlet facilities (monk, 0,4 m pipe, harvesting box) | 25 000 | |
Adjacent discharge excavated channel | ||
100 m × 4 m2 × 20 SP = 400 m2 | 8 000 | |
Total | 161 000 |
Table 3
PUMPING REQUIREMENTS (50 ha)
Water depth : 1,5 m - total water volume : 1,5×500 000 = 750 000 m3
4 water change per year : 3 000 000 m3/year
Pumping capacity : 1 m3/s = 3 600 m3/h - 75 HP Yearly pumping hours needed
Fuel needed : 835 × 75 × 0,15 = 9400 1
Table 4
SEMI-INTENSIVE FISH CULTURE
REQUIREMENT AND COSTS OF PERSONNEL
Personnel | SP/Unit/year | 8 T fish-farm | 50 T fish-farm | ||
No | Total cost | No | Total cost | ||
Manager | 54 000 | 1 | - | 1 | 54 000 |
Biologist | 36 000 | - | - | 1 | 36 000 |
Technician | 18 000 | 1 | 18 000 | 2 | 36 000 |
Labourer | 16 000 | 1 | 16 000 | 2 | 32 000 |
Unskilled labour | 14 500 | 1 | 14 500 | 4 | 58 000 |
Total/year | 4 | 48 500 | 10 | 216 000 |
Table 5
COST OF OPERATION AND INCOME
(2 YEARS)
8 ha | 50 ha | |||||
Item | Unit | SP/Unit | NB | SP | NB | SP |
Labour | Year | 216 000 | 2 | 432 000 | ||
Year | 48 500 | 2 | 97 000 | |||
Fry | 1000 | 300 | 144 | 43 200 | 900 | 270 000 |
Feed | T | 2000 | 96 | 192 000 | 600 | 1200 000 |
Fuel | T | 900 | 4 | 3600 | 20 | 18 000 |
Pumping (maintenance) | 7500 | 25 000 | ||||
Miscellaneaous | % | 10 | 10 | 194 500 | ||
Subtotal | 343 300 | 2139 500 | ||||
Depreciation | 77 550 | 398 750 | ||||
Interest | % | 5 | 67 350 | 388 250 | ||
Total cost | 488 200 | 2926 500 | ||||
Revenue | T | 12 000 | 40 | 480 000 | 250 | 3000 000 |
T | 15 000 | 40 | 600 000 | 250 | 3750 000 |
1. Management Scheme
Recent developments in the Mediterranean region indicate that intensive culture of sea-bass (Baghran), in certain settings may be commercially viable. Such a culture is analysed in this Appendix. Calculations will be made for two different farm sizes: 50 t and 300 t/year.
The farm has two types of raceways (25 × 2 m and 75 × 4 m), in order to grow the fish from fry (2 g) to fingerlings (30 g), then from fingerlings to commercial size (330 g). Fry will come from a hatchery, included or not in the farm. Feed will contain about 45% of protein and conversion index will be 1:2.5. Water change will vary from 1 l/sec for 100 kg of fish (commercial production) to 2 l/sec for 100 kg of fish (fingerlings production). Density will be 15 to 20 kg/m3.
2. Inputs
Concrete for raceways construction, and pumping station implementation accounts for the major part of farm construction costs. Therefore, the costs of raceways construction do not decrease markedly with the increase in size of the farm (assuming, as we have done, that the size of individual raceways remains about the same. The costs of pumping station implementation, on the contrary, does not increase with the increase in size of the waterpumping capacity. Depreciation and interest occupy between 20 and 25 percent of annual costs for a farm under full operation. Amongst the recurrent annual costs, fry and feed account for the greater part; energy and salaries are the two other main components. Two hypotheses are presented for each farm; a first hypothesis, with a higher rate of mortality, and a lower conversion index: this hypothesis could be used for the first 2 or 3 years of production. The second hypothesis corresponds to a well managed farm.
3. Outputs and Revenues
The farms are calculated for a production of 50 t/year and 300 t/year; costs of production vary between £S 25 and 36/kg. Sea-bass is considered as a first category fish, and £S 40–50/kg price could be obtained either on local market or on neighbouring countries markets. Comparing such prices and production costs, it appears that intensive marine fish farming could be now commercially possible in Syria. In addition, we should point out that the above analysis was carried out under unfavourable assumptions: cost of feed should be lower (£S 2.5/kg); cost of energy could be reduced by using diesel engine for pumps, etc.
RACEWAYS CONSTRUCTION AND ASSOCIATED INVESTMENTS
Unit | SP/Unit | Life time | 50 T | 300 T | |||
No Unit | S.P | No Unt | S.P | ||||
Raceways (25×2m) | each | 22 000 | 20 | 6 | 132 000 | 30 | 660 000 |
" (75×4m) | each | 110 000 | 20 | 8 | 880 000 | 50 | 5500 000 |
Water supply | m3/S | - | 18 | 1 | 500 000 | 5 | 1000 000 |
Power distribution | kw | - | 15 | 70 | 80 000 | 350 | 300 000 |
Power generator | kw | 10 | 60 | 60 000 | 300 | 210 000 | |
Buiding | m2 | 2000 | 10 | 200 | 400 000 | 1600 | 1200 000 |
Equipment | - | 5 | - | 180 000 | - | 510 000 | |
Miscellaneous | % | - | - | 10 | 223 000 | 940 000 | |
Total | 2455 000 | 10 320000 | |||||
Depreciation | 198 660 | 699 600 |
PRODUCTION SCHEME OF SEA-BASS (DICENTRARCHUS LABRAX)
IN THE MEDITERRANEAN
Phase | Duration (months) | Initial weight | Final weight | Conversion rate | Mortality % (first years) | Mortality % (full operation) |
Hatchery | 4 | 0 | 2 | - | - | - |
Fingerling production | 3–3.5 | 2 | 25 | 1.5 | 25 | 20 |
Commercial production | 3–6 8–13 | 25 70 | 70 330 | 2.5 2.5 | 15 20–40 | 10 20 |
INTENSIVE MARINE FISH FARMING
REQUIREMENTS AND COSTS OF PERSONNEL
Personnel | S.P/Unit/Year | 50 T | Fish-farm | 300 T | Fish-farm |
No | Total Cost | No | Total Cost | ||
Manager | 54,000 | 1 | 54000 | 1 | 54.000 |
Biologist | 36,000 | 1 | 36.000 | 2 | 72.000 |
Technician | 18,000 | 2 | 36,000 | 6 | 108.000 |
Labourer | 16,000 | 2 | 32,000 | 10 | 160.000 |
Unskilled labour | 14,500 | 4 | 58,000 | 20 | 290.000 |
TOTAL | 10 | 216.000 | 39 | 684.000 |
REQUIREMENTS AND COSTS OF FINGERLINGS
50 T FISH - FARM
H 1 | H 2 | |||
Weight of fish (g) | Mortality(%) | Number | Mortality(%) | Number |
330 | 25 | 150 000 | 20 | 150 000 |
70 | 15 | 200 000 | 10 | 187 500 |
30 | 25 | 235 000 | 20 | 210 000 |
2 | - | 313 500 | - | 260 500 |
Costs : H 1 : 313 500 × 1,5 = 470 250
H 2 : 260 500 × 1,5 = 390 750
REQUIREMENTS AND COSTS OF FINGERLINGS
300 T FISH - FARM
H 1 | H 2 | |||
Weight of fish (g) | Mortality (%) | Number | Mortality (%) | Number |
330 | 25 | 900 000 | 20 | 900 000 |
70 | 15 | 12 00000 | 10 | 1125 000 |
30 | 25 | 1412 000 | 20 | 1250 000 |
2 | - | 1882 000 | - | 1562 500 |
Costs : H 1 : 1 882 000 × 1,2 = 2258 400
H 2 : 1 562 500 × 1,2 = 2258 400
ANNUAL RUNNING COSTS FOR A PRODUCTION
OF 50 T PER YEAR
Unit | S.P/Unit | H 1 | H 2 | |||
No | S.P | No | S.P | |||
Personnel | Year | 216 000 | 1 | 216 000 | 1 | 216 000 |
Fry | 1000 | 1500 | 313,5 | 470 250 | 260,5 | 390 750 |
Feed | T | 3000 | 150 | 450 000 | 125 | 375 000 |
Electrecity | 1000 kwh | 350 | 400 | 140 000 | 400 | 140 000 |
Miscellaneous | % | - | 10 | 127 625 | 1C | 112 175 |
Sub-total | 1403 875 | 1233 925 | ||||
Depreciation | 198 660 | 198 660 | ||||
Interest | % | 5 | 228 040 | 5 | 215 295 | |
Total | 1830 575 | 1647 880 | ||||
Cost/kg | 36,60 | 33 |
ANNUAL RUNNING COSTS FOR A PRODUCTION OF
300 T PER YEAR
Unit | S.P/Unit | H 1 | H 2 | |||
No | S.P | No | S.P | |||
Personnel | Year | 684 000 | 1 | 684 000 | 1 | 684 000 |
Fry | 1000 | 1200 | 1822 | 2258 000 | 1562,5 | 1875 000 |
Feed | T | 3000 | 900 | 2700 000 | 750 | 2250 000 |
Electricity | 1000 kwh | 350 | 1577 | 551 950 | 1577 | 551 950 |
Miscellaneous | % | - | 10 | 619 400 | 10 | 536 100 |
Sub-total | 6813 350 | 5897 050 | ||||
Depreciation | 699 600 | 699 600 | ||||
Interest | % | 5 | 1027 000 | 5 | 958 300 | |
Total | 8539 950 | 7554 950 | ||||
Cost/kg | 28,5 | 25,2 |
COMPARAISON BETWEEN INTENSIVE FISH FARMING, MARINE FISHERIES
AND CHICKEN PRODUCTION
Requirements for 1 T of production | Requirements for S.P. 1000 of production1 | |||||
Marine fish farming | Marine fisheries | Chicken | Marine fish farming | Marine fisheries | Chicken | |
Investments (S.P.) | 35 000 | 53 000 | 20 000 | 1 500 | 4 100 | 3 000 |
Manpower (man-year) | 0 13 | 0 36 | 0 07 | 0 003 | 0 028 | 0 010 |
Emergy (S.P.) | 1 840 | 2 320 | 600 | 55 | 180 | 90 |
Imported food components (S.P.) | 4 110 | - | 3830 | 120 | - | 570 |
( 1 ) Marine aquaculture : S.P. 35/kg
Marine fisheries : S.P. 13/kg
Chicken (alive) : S.P. 6.7/kg