This report consists of two parts. The first part is a narrative report containing the findings made during field visits and possible course of action. The second part details the recommendation and technical drawings based upon the possible course of action. References to specific sections or technical drawings found in the second part are no longer made in the first part. The engineering designs provided in this report are indicative in nature and are prepared in such a manner as to contain sufficient information for experienced civil engineers to prepared detailed engineering designs.
The original terms of reference that was agreed upon between the CTA, IRA/89/041 and the NPD on 16 August 1992, prior to the CTA's departure from Iran are as follows:
Sr. Aquaculturist
observe the harvest of at least 2 remaining ponds in Kollahi, collect information on 3 other ponds scheduled to be harvested earlier and come up with a production analysis report.
Together with the Aquaculture Engineer, develop 2 prototype master plans for shrimp culture development, one for low tidal range area such as Bushehr and the other for a high tidal range area such as Hormuzgan.
Aquaculture Engineer
Inspect at least 2 sites, one in a low tidal range area (Bushehr) and the second in a high tidal range area (Hormuzgan) for the purpose of revalidating previous findings on the area.
Together with the Sr. Aquaculturist, develop 2 prototype master plans for shrimp culture development which can be used by Shilat in allocating available land to interested private investors.
Refine, and provide enough details and engineering specifications to conceptual plans for hatchery and pond development previously prepared by the Sr. Aquaculturist, to enable local engineers to prepare detailed engineering designs.
The above terms of reference were premised on a November 1992 visit. However due to circumstances beyond the consultants' control the visit was delayed by 8 months. During the interim, a lot of development had transpired in the area of shrimp culture development in Iran. Accordingly therefore, the tasks were specifically defined during a series of briefings made by the Shilat Aquaculture Department Director. In effect the tasks given to the consultants were tailored to the specific needs of each of the 3 coastal provinces involved at the time of the visit.
Visit the area under development at Cho-ebdi, Bahmanshir River and recommend possible improvements on design as necessary
Come up with a practical plan for establishing a hatchery in Mahshahr (near Bandar Imam Khomenei) using an existing warehouse within the Shilat fishing port complex. The hatchery shall be used for producing P. monodon fry using imported spawners.
In case the warehouse area is not sufficient to accommodate a 100-million PL capacity hatchery, come up with a practical plan for a hatchery that can produce enough PL to fill the deficiency and recommend a possible area where such a hatchery may be established.
Identify possible alternate hatchery sites for Khuzistan.
Visit Hendijan area and determine its potential for any shrimp culture activity.
Supervise in detail the hatchery work in Kollahi and advise the Kollahi staff on improvement in operations giving particular attention to the poor results obtained in the larviculture of P. merguiensis.
Inspect old Shilat cold storage building in Jask and determine the possibility of converting it into a shrimp hatchery.
Inspect unused warehouse at the Shilat Bandar Abbas compound and determine possibility of converting it into a shrimp hatchery.
Visit 1,000 ha area along Helleh River and come up with a master plan for subdividing it into 50 units of 20 ha shrimp farms for distribution to interested private investors and develop a practical layout for a 20 ha farm unit.
Identify other sites in Bushehr outside the Helleh River area for possible shrimp farm development.
Additionally the consultants were also requested by the UNDP Resident Representative to look into the possibility of formulating a project for UNDP assistance on a cost-sharing basis for direct government execution as a follow-up to IRA/89/041. The said project should have as its thrust the development of capability of Shilat to extend assistance to the private sector in shrimp farming.
The Consultants departed from Manila on 4 May, 1993, and were in Rome on 5 – 8 May for briefing at FAO HQ and to collect their entry visa to Iran. They arrived in Tehran on 9 May and left on 16 June. During the 6-week duration of their stay in Iran, they alternated between Tehran and the coastal provinces as detailed in their itinerary (Annex 1), met with, and were assisted by, various individuals (Annex 2).
The approach taken by Shilat was to brief the Consultants on the specific tasks expected of them in every province before sending them out. They were then brought back to Tehran to debrief the Director of the Aquaculture Department on their findings and at the same time to receive specific instructions on the task ahead on their next field visit. Any requirement to enable the Consultants to carry out the specific tasks in each province such as maps, survey instruments, etc. were also conveyed in advance during such meetings. In Tehran they prepared preliminary plans based on their field findings after each trip and presented these for discussion with the Shilat technical staff.
Since August 1992, when the Senior Aquaculturist left Iran after his one-year tour of duty, the Aquaculture Department of Shilat had taken several steps to hasten the development of a shrimp culture industry in the country. This was learned during the initial briefing given by the Director of the Aquaculture Department upon arrival of the consultants. In brief these are as follows:
Shilat has established 20 ha demonstration shrimp farms in the other coastal provinces and has embarked on completing the unfinished pilot farm in Kollahi, Hormuzgan province.
Ponds for shrimp culture trials along the Caspian sea coastal area are also being constructed in Mazandaran.
Based on the encouraging results of the trial culture of the black tiger shrimp, P. monodon, at Ghofaz, Khuzistan province, along Bahmanshir River (a harvest of 1.7 tons per hectare was reportedly attained), Shilat has released 300 ha to the private sector in Cho-ebdi, which is located at the opposite side of Bahmanshir River. The Ghofaz area cannot be used for such purpose because it has been declared a sanctuary for migratory birds by the Environmental Protection Organization. Of the 300 ha released, some 100 ha is expected to be completed within 3 months.
Shilat ran a public advertisement in their in-house magazine in March 1993, inviting private parties to invest in shrimp culture. As an incentive, Shilat is to provide shrimp fry and feeds during the first year of operation. About 100 parties responded to the advertisement but only 20 has been granted permits some have already started construction work.
Target species for the Bahmanshir area is the black tiger shrimp in order to take advantage of the brackishwater supply. Initially, Shilat shall import the required fry stock from Malaysia. Once a large scale hatchery is ready, the stock import shall shift to spawners and broodstock so as to reduce the cost of importation.
Shrimp feed shall initially be imported (from Thailand). At the same time however, attempts shall also be made to formulate feeds locally in cooperation with a commercial feed mill. An initial batch of 1,000 kg have already been produced for immediate testing in the Kollahi grow-out ponds.
During the next 5-year national development program, shrimp culture development shall be given priority and the required infrastructure are to be established.
The test farm used for P. monodon trial culture in Summer/Fall 1992 is located in Ghofaz, along the west bank of Bahmanshir River. It consists of 4 units 0.45 ha ponds and a 0.65 ha reservoir pond which also served as a sedimentation pond. Water is pumped up from the river to the reservoir pond and after a reasonable period of time for the sediments to settle, the water was pumped directly to the grow-out ponds. Shrimp fry from Malaysia were stocked in July 1992 at a density of more than 10 per m2. These were fed with pelletized feed imported from Thailand and were harvested 3 months later by November due to the onset of the cold season. The harvest was reportedly equivalent to 1.7 tons/ha with an average shrimp size of 15 g. The small size was attributed to the limited growing period but was nevertheless considered a big success.
However, it later turned out that Ghofaz is considered a sanctuary for migratory birds by the Iranian environmental agency which has forbid any further development along the west bank. Shilat therefore decided to earmark the river's east bank for shrimp culture development instead. Here, in the village of Choebdi, a 20 ha demonstration farm is being developed. Adjacent to the Shilat farm, 2 other groups are also developing their 20 ha farms. Two tracts of land, one measuring 5,000 ha and the second 2,000 ha has been marked for large scale expansion on a 1:50,000 topographic map but has not yet been actually surveyed.
The 20 ha demonstration farm at Cho-ebdi is basically a scaled-up version of the earlier farm at Ghofaz. It is designed with a reservoir which shall be served by 10 units of 20 cm discharge volute pumps (8 operating and 2 reserve units). Water from the reservoir shall be pumped for distribution to the grow-out ponds using 5 units of the same size pump (4 operating and 1 reserve), through above-dike concrete flumes. The number of pumps for the first stage pumping (river to reservoir) is double that for the second stage (reservoir to ponds) due to the limited hours imposed by the tidal regime. Both sets of pumps are to be housed in one pumping station.
The design of the proposed demonstration farm conforms with basic engineering standards. However some improvements can still be made in the water intake system to make it capable of drawing water from different levels so as to have some degree of choice on the salinity level. Furthermore locating the second stage pumps in the same area as of the first stage pumps while seemingly advantageous in the sense of having a single pump house is not practical since it will not be possible to change water while simultaneously filling the reservoir pond since it would result in the transfer of the river water's full silt load. Relocating the second stage pumps to a point farthest from the first stage pump will also make possible the simultaneous transfer of water to the rearing ponds even as the reservoir pond is being filled, with the silt load considerably minimized. The additional expense entailed in constructing 2 pump houses, with the second half as large as the first, is not likely to be substantial, but will result in a more functional water supply system.
It was suggested during one of the technical meeting that the actual intake points of the 5 pumps involved be transferred to the far side of the reservoir pond by installing pipes in order to achieve the same purpose as actually relocating the pumps. While this may be so, it is doubtful if this is actually cheaper than splitting the pump house into two, considering that 5 large pipes each with a diameter of 20 cm are involved and that these have to be laid over a distance of 300 m. Besides, five large pipes laid across the pond bottom represents so much obstruction to water flow especially when draining the pond for periodic clean up. All in all, having a separate pump house for the second stage pumps is considerably simpler than extending the intakes by installing pipes.
Located some 150 km south of Ahwaz and less than 25 km from Bandar-e-Imam Khomenei, one of Iran's major international port, which overshadows it, Mahshahr is often informally referred to through the bigger port's name. Shilat has built a fishing port with cold storage facilities in Mahshahr to serve Khuzistan province. Within the fishing port compound a large warehouse with a floor area of 4,202 m2 lies unused. It is this warehouse that the consultants examined for possible conversion into a shrimp hatchery. Within the fishing port complex both freshwater and electricity are already available. Seawater can be drawn from the pier which is built along a deep channel through which fishing boats can readily pass through even during the lowest tide.
The channel is deep enough for fishing boats to dock even at low tide. Water is generally murky at low tide but appears to be relatively cleaner when the tide comes in. Some oil slicks and garbage, probably from the fishing boats were observed. But these did not appear to stay and were flushed away constantly by the tidal currents. At the time of the visit, the salinity of the water measured 42 ppt. Other than the oil slicks, the water did not show any other sign of pollution. No unusual smell or discoloration was observed. Indeed fish were seen to be swimming normally at all times.
A trial hatchery has been set up close to the warehouse. This was reportedly intended for marine fish. This consisted of a shed made of temporary materials (reed matting for wall and roof in a steel frame). One side of the shed was inexplicably left open, while the opening at the opposite side was not provided with a door. Thus effectively it was open from two sides. The seawater supply system consisted of a centrifugal pump, a large sedimentation tank which serves as a reservoir, and a header tank. The sedimentation tank was fitted with a vertical filter consisting of a double steel screen mesh filled with crushed gravel. Asphalt was used to make the sedimentation tank waterproof, since it was made of concrete hollow blocks. The culture tanks consisted of 2 m square fiberglass tanks with a depth of 50 cm.
According to the expert in charge of the temporary hatchery, only one attempt has been made to breed shrimps using M.affinis, but no eggs were recovered although signs of spawning were observed. Further inquiry revealed that the seawater was used without any treatment (EDTA, chlorination and dechlorination), as is the usual practice in Bushehr and in Kollahi.
The warehouse was found large enough to house a hatchery with a capacity of 100 million shrimp fry over a period of 3 months. Due to the turbidity of the seawater supply and the limited times when it would be safe to pump in seawater with a low risk of any oil material being sucked in, it will be necessary to construct a reservoir which will also serve as the sedimentation tank. In addition, two large rapid sand filters will also be required to further clarify the water. Two filters are required so that one can always be in active use while the other is being backwashed.
Khuzistan has a very limited coastline along the persian Gulf. Most of these are low lying, silty and with very flat slope. The only exception is along the channel leading towards Bandar-e-Imam Khomenei and Bandar-e-Mahshahr. This channel is deep and navigable even for large ocean liners. Even within this area however, the land itself is low lying and is submerged during high tide. Consequently any land development requires filling with borrowed soil material. All the roadways as well as the shilat fishing port complex are built on reclaimed land.
With such a terrain it would be expensive and impractical to establish a hatchery outside those areas which have already been reclaimed. At any rate should there be a need for additional hatchery capacity, there appears to be sufficient land space within the already reclaimed area of the Shilat fishing port complex.
Hendijian and its vicinity, namely Zohre River and Bahrikon Sar has a coastal profile in the form of a very wide, almost flat intertidal area. At Bahrikon Sar a jetty has been built in order to enable fishing boats to dock and facilitate the transport of the catch to the market. This jetty now extends 600 m seaward from the high tide line. Yet inspite of its length, the edge of the water at low tide is still several hundred meters away. It is estimated that the jetty would have to be extended by at least 500 m before it will reach an acceptably deep area where small fishing boats can dock even at low tide to facilitate the unloading of the fishermen's catch.
The soil at Bahrikon Sar ranges from silty clay to silty loam. However this type of soil is found only at the top layer which ranges in depth from 2.0 m at the upper intertidal line to below 0.5 m towards the lower intertidal line. When dug, the nature of the substrate changes to a form of black mud the particles of which are loose and show no sign of cohesion or plasticity whatsoever. Soil studies previously made by a local engineering firm (Sazeh Pardazan) in connection with other projects envisioned in the area have shown that the soft subsoil extends as much as 25 m below before hitting stable layer. Indeed during the visit it was observed that a two meter long rod can be shoved down the ground with very little resistance.
At the Zohre River banks, the land is low lying although like Bahrikon Sar the actual water line at low tide is actually very far and hardly accessible. Zohre river itself appears to be heavily silted at the mouth and has no free access to the sea. During the visit, the tide was still going down but river water was no longer observed to be flowing. Indeed during the visit although arrangements were made for a boat trip out to the river mouth, this could no longer be made due to the obstruction.
Due to the nature of the coastline and the nature of the subsurface soil it appears that the area is completely unsuitable for any shrimp culture development activity. In the Bahrikon Sar area ponds can conceivably be developed only in the upper intertidal and supra-tidal area in order to avoid the soft muddy layer. However this will mean as much or even more than 2 km distance from the water's edge at low tide. This means a long supply canal in order to have access to the water. However excavation of a canal is out of the question due to the nature of the subsoil. Since such a canal would without any doubt hit the black mud layer, the loose nature of the black mud means the canal will just fill up with black mud as fast as it can be dug.
A suggestion was made during a technical meeting to pipe in the water. First of all'a supply pipe for shrimp ponds will need to be very big. For a 100 ha area it is estimated that a minimum pipe diameter of 9 m will be required. Such a pipeline will need some kind of support at regular intervals in order for it not to break. Since it has been determined that stable ground is at least 25 m below, this would probably mean driving piles down to that level. It should also be noted that a shrimp pond is not merely a hole in the ground. Some structures such as sluice gates and a pumphouse are invariably needed. Again these structures can hardly be built without an adequate and stable foundation. Needless to say, in any currency, it would be extremely unwise to even think of such an undertaking. It is a basic premise that shrimp culture, or any aquaculture activity, is site specific. It is for this reason that site selection is an unavoidable prerequisite. Some coastal areas are suitable. Some are not. Hendijan just happens to be one of those which are not.
The township of Jask is located in a cape which juts out into the Sea of Oman. The promontory itself is a narrow U-shaped tongue of land with one end of the U attached to the mainland and the other end free, thus forming a sheltered cove connected to the open sea by a very narrow channel. Local people refers to the cove as the “small sea” and the open waters as the “big sea”.
The Shilat complex, which includes the usual fishing port, ice plant and cold storage facilities, is located along the small sea. The old cold storage plant under consideration as a possible hatchery was built in 1978. It is no longer in use as a cold storage having been superseded by a new and larger plant. However part of it is being used as offices, kitchen, dining room and a mezzanine has been converted into quarters for Coast Guard personnel detailed to the area. All the refrigeration machineries are still in place. The whole building is made of steel. Some of the metal paneling are already rusty in places and may need localized repairs, but the whole unit appears to be still structurally sound.
The water in the small sea, as can be expected, is not as clear as that of the big sea, but is still of much better quality than the seawater supply of either the Kollahi or Bushehr hatchery. The ice plant draws its seawater supply for making sea ice from inshore wells. The wells are 11 m deep and the water at high tide is 6 m deep. The well water has a very high transparency with the bottom of the well always clearly visible. The surface salinity of the well water ranges from 37 ppt during low tide to 42 ppt at high tide. This shows some ground water influence.
Freshwater is supplied by a tanker into the shilat complex but is always available. A ground level reservoir with a capacity of 200 m3 is built in as part of the old cold storage plant and is still in use. From this reservoir the water is distributed throughout the complex by pumping. A supply of slightly brackish water with a salinity of 5 ppt drawn from a deep well in a nearby village is also available and arrangements can apparently be made to pipe it in if required. This particular water supply has actually been developed to serve a housing compound for Iranian Air Force personnel located just across the road from the Shilat compound.
The electrical power supply in Jask is generated locally and is not yet connected to the national power grid. The generator in use is old, inadequate and unreliable. However it is already scheduled for upgrading. In the meantime the Shilat cold storage plant is equipped with a 1,000 kva trailer type generator which is used whenever the ice maker is in operation.
Jask is easily accessible and is served by the main coastal highway which leads all the way to Bandar Abbas, about 285 km away. It has an airfield maintained by the Air Force but which reportedly is served by a once-a-week commercial flight from Tehran. Telephone service is available.
In terms of seawater quality, Jask is definitely one of the better sites in Iran for a marine hatchery. Furthermore temperature wise, Jask being farther south than Busher or Khuzistan, can be expected to get warm earlier in spring. Its only disadvantage is its relative distance from the possible grow-out pond areas. Jask do not have any site that can be used for pond development. However it should be noted that the packing and transport of shrimp fry over long distances is a very well established practice and should not be considered a big obstacle. From the possible pond areas within Hormuzgan, Jask should be within a 5 to 8 hour driving distance. The inadequate and less than reliable local supply of electricity should also not be considered a big problem. Even in an area with good electrical supply a stand-by generator is still required. With the available floor area and assuming that the present offices and living quarters will not be vacated, it should be possible to develop the remaining area into a hatchery with a capacity of 30 to 40 million postlarvae during 3 to 4 month operation.
A marine hatchery in Jask will have the advantage of not requiring an expensive seawater sedimentation and filtration system. Water drawn from an inshore well is pre-filtered and can be used directly. The old cold storage plant although rusty in some places can still be renovated to house the required larval rearing tanks.
The coastline of Bandar Abbas and its vicinity is not the type of area which one would select for a marine hatchery. The intertidal area is very wide due to the very gentle slope of 4:10,000 or less and the relatively high tidal range of 4.2 m. The coastal soil is generally silty to silty clay making the coastal water always turbid. With this kind of beach profile drawing of clean seawater becomes an expensive proposition since it would be necessary to run a supply pipe across the intertidal flat so that the intake will be within the subtidal area where the water would normally be relatively cleaner. This would involve a distance of more than 1 km. Furthermore with such a distance it would be necessary either to locate the pump station right over the intake point. Alternatively the supply pipe has to be installed with a slope that is reversed to the natural slope so as to enable the seawater to flow by gravity to an inshore sump pit from which it can then be pumped. Generally therefore it is much simpler to just locate a hatchery in an area where the beach profile is relatively steep or alternatively where the substrate is sandy and an in shore well capable of yielding clean water.
The above condition applies to the Shilat compound in Bandar Abbas. Although located along a beachfront, the water at low tide is actually more than a kilometer away and the water is always turbid. However Shilat has recently started to build an earth-filled concrete jetty to enable fishing boats to dock and unload their catch even at low tide. As designed the jetty will be extended up to the point where the minimum water depth will be 0.8 m even at low tide. At the time of the visit, construction of the jetty was already more than half way towards the target depth.
The presence of the jetty makes it feasible to get relatively cleaner water from the subtidal area without incurring a large expense. Upon completion it would be easy to install a seawater pipeline along the jetty and to construct a pumphouse right over the intake. However a filtration system will still be required in order to remove both inorganic and organic particles in the form of small marine organisms which are unavoidable in an open intake system.
The empty warehouse which is being contemplated for alternate use including possible conversion into a marine hatchery, is relatively new. Beside it is adequate space for a filtration and seawater treatment system. Electricity and fresh water supply is available. Brackishwater with a salinity of 12 ppt is also available from a well within the compound. The warehouse is just one big hall with a floor area of 1,166 m2 without any partition. The required larval rearing and postlarval tanks can easily be laid inside the building. It is estimated that the building can house a hatchery with a capacity of 25–30 million shrimp fry per season.
The main task laid out for the visit to the Shilat Shrimp Culture Station in Kollahi was to examine in detail the hatchery operation and offer expert advise on ways to improve the operation with emphasis on the larviculture of banana shrimp, P. merguiensis, which reportedly was encountering survival problems. Accordingly the culture history for the past runs were obtained and examined.
As can be seen in Table 1, the Kollahi hatchery started their first P. merguiensis run on 7 April, 1993 when the temperature still ranged between 24 to 25°C. The low temperature persisted during their first 4 runs and became better only on their fifth run. As can be expected, larval development was greatly delayed at low temperature levels. It took 9 days during the first two runs and going down to 8 then 7 days only on the third and fourth run as the ambient temperature increased as the season progressed. In the fifth run, as the temperature edged towards 28°C, the length of time for the nauplii to reach Mysis stage went down to 6 days.
In the first run, attempts were made to rear the larvae through even when the survival was very low after reaching Mysis-3. Instead of discarding the whole batch the larvae were transferred to a small fiberglass tank. As can be expected less than 1,000 postlarvae were recovered. The second to fourth run were discarded at M-3 stage. Only the fifth run reached postlarval stage with a sufficiently high survival rate as to be readily visible.
For larval rearing in a hatchery the water temperature should be stable and should ideally be within the range of 28 to 32°C. At low temperature, larval development is delayed and the larvae are generally weak and may be abnormal in the sense of not attaining full metamorphosis. Very few of such larvae reaches the postlarval stage, as can be seen in the first run. In fact it is better not to waste time, feed and tank space for such runs.
Subsequently, the hatchery had two tanks of P. merguiensis which at the last day of the visit (21 May) appeared to be developing normally. It had attained Zoea-3 stage and the density did not appear to be any lower than 400,000 and 600,000 estimates made when the larvae first attained the Zoea stage.
Table 1. Summary of data on the larviculture of P. merguiensis, in the Shilat Shrimp Culture Station Hatchery in Kollahi in April to May, 1993.
| Run No.: | 1 | 2 | 3 | 4 | 5 |
| Temperature Range (°C): | 24–25 | 24–25 | 26–27 | 26–27 | 27–28 |
| Number of Spawners: | 24 | 16 | 2 | 4 | 5 |
| Hatch Date: | 07/04 | 12/04 | 30/04 | 01/05 | 06/06 |
| First Count (x1,000): | 1,925 | 1,000 | 300 | 200 | 150 |
| Z-1/Z-2 | N-6 | N-1 | N-2 | N-4 | |
| Date Mysis: | 16/04 | 21/04 | 08/05 | 08/05 | 12/05 |
| No. Days N-1 to M-1: | 9 | 9 | 8 | 7 | 6 |
| Last Stage Attained | PL's < 1,000 | M-3 | M-3 | M-3 | PL-6 as of 21/05 |
The hatchery did not appear to have any problem with the two other species it was rearing, namely, P. semisulcatus and Metapenaeus affinis. At the time of the visit the nursery tanks had a stock of 240,000 postlarvae (PL-31) of the former and about 1,000,000 PL-30 and PL-31 of the latter species. The larval rearing tanks were also full, two with M. affinis PL-4 stage totalling almost 500,000 and three with P. semisulcatus ranging from Z-3 (230,000) to M-3 (300,000) and PL-6 (less than 10,000), in addition to the 2 tanks with P. merguiensis mentioned previously. It appears that the banana shrimp is more sensitive to low temperature than the other two species.
The station head is fully aware of the temperature problem during early spring. For this reason an oil-fired steam generator has been installed to produce heat for a heat-exchange loop in the newly constructed outdoor seawater treatment tank. The steam generated is also piped to radiators inside the hatchery to heat the air space. Unfortunately the heating system was installed too late to be of use during the cold months. However it should prove useful for the next season. Spawning and hatching is done in a small room which is heated using electrical radiant heaters. Here the air temperature is maintained at 30 to 32°C.
The construction of two water treatment tanks between the hatchery building and the water tank now frees the two circular tanks inside the hatchery for use as treatment tanks for algal culture. The algal culture area itself is now being enclosed using corrugated fiberglass sheets. Plans are being made to transfer the hatchery water supply intake from its present location in one of the rearing ponds (which also serves as a sedimentation pond), to the nearest branch of the khowr or tidal inlet. This will require the construction of a large reservoir so as to be assured of seawater supply even during low tide when the khowr is empty.
At the time of the visit none of the rearing ponds have been stocked yet. In the meantime construction of drainage gates for the unfinished ponds was on going. Supply gates in those ponds which are not yet so equipped will no longer be constructed. Instead these ponds will be filled through the drainage gates. New water for management purposes will be supplied either by pumping and distributed by pipe or by an open concrete flume to be installed above the dike. Two submersible pumps with 20 cm discharge which were ordered in August 1992 are already in he country but has not yet been released by the Customs office as of June 1993. It is hoped that these pumps can be released on time to be used for the 1993 growing season.
The Kollahi station appears to be operating smoothly under a newly installed station head. One of the positive development is the hiring of technicians from the local community rather than from Bandar Abbas. Being from the locality they are available to render service even during weekends or holidays if so required. The new recruits appear to be motivated. It was noticed that there was a tendency to overfeed thus resulting in rather high diatom density in the larval tanks. This is a common error that can be attributed to their relative lack of experience and enthusiasm to succeed. In time and with proper supervision it can be expected that these new recruits will develop into seasoned hatchery technicians.
Three shortcomings were noted during the visit. The most important because it is fundamental in nature is the apparent lack of autonomy in its operation. For instance in the matter of pond stocking, the station have to wait for specific instructions from Tehran. At the time of the consultants' visit, some 240,000 fry of P. semisulcatus (PL-30) were ready for stocking and at least two ponds have already been prepared. However due to lack of instructions from Tehran the postlarvae have to overstay in the concrete nursery tanks. Another matter of serious concern is the lack of a qualified person to take charge of the well-equipped algal culture laboratory. Good quality natural feed is a keystone for successful larval rearing. The third matter is the lack of awareness on the importance of maintaining the rapid sand filter in good condition through regular backwashing. It was noted during the consultants' visit that the surface of the rapid sand filter have caked and overgrown with algae. This impairs filtration rate and makes the filter inefficient.
Shilat is facing strong public pressure to rapidly develop the shrimp culture industry in Bushehr following a recent visit of no less than President Rafsanjani to the province during which he promoted shrimp culture as an attractive investment and means of livelihood. Accordingly shilat Bushehr has identified a 1,000 ha along Helleh River which is intended to be subdivided into family size farms of 4 ha and company-size farms of 20 ha. Shilat has already started to develop a 20 ha lot within the 1,000 ha area into a demonstration farm which will be the nucleus of the coastal aquaculture center for Bushehr.
The proposed shrimp farm estate area is located about 600 m northwest of Helleh River at the nearest point. The eastern end of the 1,000 ha area is about 6 km from the sea and the western end about 2 km. The general soil type is silty loam. Better soil can actually be found nearer the river mouth at the opposite bank of Helleh River. However the area is a waystop for migratory birds during winter and has been declared off limit to any type of development by the environmental protection agency. The soil type is clearly less than ideal for pond development. With such type of soil the embankments have to be large and have to be designed with a slope of 1:3.
At the time of the visit the area has been surveyed but topographic survey had been completed only for the 20 ha Shilat demonstration farm area. The layout for the 20 ha farm had already been prepared. A profile had also been made along the proposed supply canal line from the khowr to Helleh River. The local benchmark was not yet tied to the sea-level benchmark or to the tidal datum. Inexplicably the lot map did not indicate the actual location of the river, the khowr nor the Shilat farm. With an obviously insufficient data, the consultants were expected to prepare the layout for the 1,000 ha farm estate and determine the location of the main supply and drainage canal immediately after the site visit.
The engineer in charge of the design work was made to understand that it is not possible to do any intelligent layout without knowing the exact location of the farm site relative to the river and the khowr and the general elevation of the land relative to the tidal datum. The consultants were finally provided with a sketch based on table survey using a 1:50,000 topographic map indicating the location of the 1,000 ha farm site relative to the river and the khowr. It is on the basis of this vicinity map that a layout was prepared with the assurance from the Shilat engineer (Mr. Majtaba Salimi) that he is taking full responsibility for any error that may result from the use of such an unscientific data.
The layout of the 20 ha Shilat farm is basically sound. However the consultants are not convinced on the need to have the 2,500 m2 ponds. Small ponds are more expensive to developed and not applicable for commercial semi-intensive farms. With the poor soil quality soil, large dikes are necessary. In order to have enough soil for dike construction without over-excavation, soil has to be borrowed from another area and transported by truck thus adding to the development cost.
It is also difficult to understand why Shilat had to select the farthest point from the khowr for the demonstration farm. This unnecessarily complicates and delays the completion of the demonstration farm, even granting that high development cost is not a problem. As it is Shilat will have to construct a 4 km long seawater supply canal and an equally long drainage canal just to serve a 20 ha area.
In order to serve the strong public demand for shrimp farm sites in Bushehr, Shilat engaged the services of Jihad Consulting Engineers to identify other areas which may be suitable for shrimp culture development, with the assistance of these consultants. Site visits were made to eight different sites from one end of the province to the other. The search considered two parameters as the main determinant to classifying an area as suitable or not: soil type and access to clean seawater. On this basis, the following areas are rated accordingly.
Assaluyeh. This site is located near Hormuzgan provincial border. The foreshore area is an emerging mangrove. A dense growth of Avicennia, still low and bush like was observed. The beach profile shows a very gentle slope and consequently a wide intertidal area. A khowr or tidal inlet present but is blocked by a sand bar. The area near the mangrove is clayey sand. About one kilometer inland is a wide open flat with no vegetation whatsoever. The soil within his flat appears to have a high clay content and may be considered clay-loam in nature. It is definitely a very good material for pond development. Unfortunately access to water is likely to be a problem. Even if the inlet is dredged it is doubtful that it can be maintained open for a long time. The beach area is sandy. The beach processes brought about by wind and wave action is generally very dynamic and capable of shifting a large volume of sand around. It should also be noted that any development in the foreshore area may have a negative impact on the emerging mangrove forest which should be protected. For this reason his area can be considered to have a very low potential for development.
Khowr-e-Bardestan. This inlet is located in the town of Dayer, almost 200 km southeast of the city of Bushehr. At the time of the visit the tide was low but the inlet still had a width of 50 m. The depth at the center reportedly measures 2 m even at low tide. The water was clear and had a salinity of 42 ppt. The general elevation was estimated to be about 1.7 m above the water level (16:40 hrs, 7 June). Along the tidal creek, a thin layer of pure sand overlays a generally sandy-loam substrate. Excavation at a point about 300 m from the creek reveals a generally sandy-loam top soil of 40 cm overlying a clayloam substrate. It is estimated that some 180 ha is available for development in this locality. This site can be considered as having a good potential for development and should be studied further.
Bordkhun. This area is located only 50 km northwest of Bardestan. There is no tidal inlet present. The coastal slope appears to be relatively steep, and the intertidal area narrow. Soil type is similar to that of Bardestan. A tidal supply canal is workable since the soil is good and the distance to be traversed to reach the zero datum elevation is not too far. Some 3,000 ha is estimated to be available for development in this area.
Mond River Area. It takes about 2 hours to reach the Mond River bank from the main road. The river is a big one. Close to the mouth the width was more than 100 m. Minimum depth at the river center at lowest tide is reportedly 4 m. The surface salinity at the time of the visit measured 10 ppt. The land within the area was generally low, probably within 2 m above datum. A layer of coarse sand, reportedly moved about by wind action covered the entire area occurring in heaps in some spots. At the river bank itself the soil appears to be silty loam. About 250 m away the soil ranges from sandy clay to sandy clay loam with pockets of pure sand. The ground is water logged. Due to the abundant brackishwater and the quality of soil, this area definitely deserves to be surveyed at greater depth to determine its suitability. Before embarking on such a study however it would be advisable to check with the environmental agency since the area looks just like the type that would attract migratory birds.
Delvar. Its 30 km distance from the city of Bushehr, makes Delvar an attractive area for development. In fact a private company has already staked out its claim to the area, having purchased a boat-building shed for possible conversion into a hatchery with an initial 20 ha of grow-out ponds to be developed nearby. Unfortunately the soil is poor. The upper 35 cm is silty sand with pockets of clay. Below this layer up to 60 cm is a layer of pure sand. Lower than 60 cm the soil becomes silty clay. During soil sampling with a shovel the hole starts to fill with water as the sand layer is reached. Pond construction will probably require a prior mixing of the soil in order to produce a homogeneously acceptable diking material. Water supply would be a problem since the tidal inlet, which is the most likely water source is shallow. Considerable dredging would be required. Even then keeping the inlet open might be a recurring problem.
Khowr-e-Boverat. This inlet is near Bandar Deylam and is about 180 km from Bushehr. It spanned about 15 m at low tide and is reportedly 2.0 to 2.5 m deep. The soil is silty clay in the upper 10 cm turning to sandy-silt from 10 to 80 cm. Below 80 cm is black gooey mud with very strong petroleum odor. In fact during soil sampling the strong smell of petroleum was already detected at a depth of 50 cm. With such characteristic this area cannot be considered suitable for shrimp pond development.
There are many sites in Bushehr which would be suitable for hatchery development. Towards Hormuzgan there is Kangan and towards Khuzistan, Ganaveh and Deylam. All of these areas have sandy beaches and clear water and are close to the major highway and electrical power line. Ganaveh is very close to Khuzistan and should be seriously considered as a possible site for a hatchery intended to serve Khuzistan which do not have any good site.
On the basis of the findings in the field and specific requirements of Shilat as enunciated by the Director of the Shilat Aquaculture Department, the consultants proceeded to prepare indicative plans for the hatchery and grow-out pond development. Specifically the following plans were prepared:
Conversion of Shilat warehouse in Mahshahr, Khuzistan, into a 100 million fry capacity hatchery, including indicative plans for the seawater supply and treatment system and aeration system;
Conversion of old cold storage plant building in Jask, Hormuzgan, into a 40 million fry capacity hatchery, including indicative plans for the seawater supply;
Layout and sub-division of a 1,000 ha area along Helleh River, Busher, into small (5 ha) and medium (25 ha) size shrimp farm units including indicative plans for both types of farm, and the seawater and freshwater supply and distribution system;
A model hatchery for producing 100 million fry in one season that can be built in any suitable site.
Typical designs for larval rearing tanks, nursery tanks, algal culture tanks, and broodstock tanks that can be applied to any hatchery including those in this report;
Typical designs for sluice gates, water inlets, drainage gates, pump houses, and flumes which can be applied to any shrimp farm project.
The technical drawings together with the technical description and specifications form the second part of this report under separate binding. Indicative plans for the Mahshahr hatchery and the conceptual plans for the shrimp farm estate in the Helleh River area, Bushehr, had been submitted to Shilat before the Consultant's departure from Iran and were discussed in a series of technical meetings. The Consultants have as much as possible attempted to clarify the points, answer the questions, and incorporate some of the suggestions raised during the series of meetings, in this report.
The determination of Shilat to speed up the development of shrimp aquaculture in Iran is truly commendable. It is felt however that certain aspects should be given very serious consideration before embarking on a massive undertaking. The present level of knowledge is limited to the following points:
Fry of the three major Persian Gulf shrimp species, namely P. semisulcatus, P. merguiensis and M. affinis, can be produced in mass during the spring breeding season using wild spawners.
Semi-intensive culture of P. semisulcatus in earthen ponds under using imported shrimp pellets supplemented with trash fish is capable of producing 600 kg in a half hectare pond (1,200 kg/ha) with an average size of 15 g within a 4-month rearing period using pure seawater with initial salinity of 40 to 42 ppt even with inadequate water change due to lack of proper pumps.
M. affinis is a very hardy species for pond culture. Harvest of 450 kg in a half hectare pond (900 kg/ha) with an average size of 8 g is possible even with purely tidal water management, using long expired feed pellets and trash fish as feed. Even under a neglected condition without any feed or water change a harvest of 300 kg in a half hectare pond was still attained.
The Bahmanshir River area in Khuzistan is suitable for the culture of P. monodon. Using imported postlarvae and imported feed, harvest equivalent to 1,700 kg/ha with an average size of 15 g can be achieved within a 3 month rearing period.
The successful commercialization of shrimp culture in Iran depends on the full and unstinting support of the private sector. There is no tradition for shrimp culture in Iran. The present move of Shilat offering free shrimp fry and feeds for the initial operation of the early investors is surely an attractive incentive. As can be seen in the early response the incentive is working. However the interest of the private sector can be sustained only if it can be shown that the technology is sustainable and profitable. Sustainable in the sense of having an assured supply of shrimp fry every growing season. Profitable in the sense of having an acceptably high return even after factoring in capital expenses, cost of money and opportunity costs.
A very basic issue which should be resolved is the shrimp species that should be promoted. At present the Shilat Aquaculture Department seems inclined to favor the culture of black tiger shrimp, P. monodon, a species which does not occur in the Persian Gulf. This is understandable in view of the reputation of this species as the largest and fastest growing shrimp.
However there are certain undeniable facts which should be faced with regards the black tiger. One, is the fact that the major market for black tiger shrimps is Japan and that Japanese demand appears to have levelled off to the consternation of the major producers of the species, namely Thailand, Philippines and Indonesia. Two, expanding the market for black tigers to Europe and the U.S. has not been easy. Three, all the major shrimp producing countries use indigenous species, that is P. monodon in the countries already mentioned, P. chinensis in China and P. vanamei in Ecuador. The converse is also true. Not a single country which uses imported shrimp species can be counted as a major shrimp producing country. While Taiwan did resort to importing P. monodon breeders, it should be noted that this was done to augment local supply which was no longer capable of sustaining the rapid growth of the industry and that the sources were neighboring countries only a few hours away. During the early years of their shrimp industry many Latin American countries were also tempted to culture P. monodon and managed to import some fry and develop their own broodstock. But no one succeeded in commercializing their venture. Latin American shrimp farms found success in farming their own species instead.
Shilat is aware that importation of P. monodon fry every year cannot be sustained and for that reason intends to import the spawners instead so that the postlarvae can be produced in Iran. Financially this is a wise move. It will be cheaper to transport spawners to produce the required number of fry than to transport the fry themselves. However there are certain realities that should be considered in the importation of the spawners. First of all the number of spawners that will be required in a given period for a 100-million fry per season hatchery in Iran is rather big. Due to the limitations posed by the climate, the hatchery has to produce its full capacity in the 3 months of spring otherwise. Later than that there will not be enough time to grow one crop before the cold winter months. Second, due to the travel time involved, from the possible source up to the hatchery site, it will be advisable to transport adult broodstock material rather than gravid spawners. Assuming 60% successful maturation it is estimated that 457 females will be required every two weeks.
Whether it is possible to find a supplier in Asia that can sustain such an operation is a big question. A regular supply of P. monodon breeders is always a big problem even for local hatcheries in the producing countries. It is for this reason that the governments of Indonesia and the Philippines have imposed a ban on the export of P. monodon breeders. Even Malaysia probably has a similar statute. The difficulty in finding enough spawner or broodstock material is due to the fact that the natural density of the black tiger is one of the lowest among the penaeids.
Another factor that should be considered is the fact that the black tiger shrimp is one of the most difficult species to rear in a hatchery. Many experienced hatchery technicians in Asia can attest to this. It seems to be more easily susceptible to all kinds of fungal, protozoan, bacterial, and viral disease compared to other penaeids especially in the artificially high density situation in a hatchery. There is a real danger that the importation of P. monodon shrimp stock would unnecessarily expose the Persian Gulf shrimps to some of the viral diseases.
There are at least two distinct advantages to using an indigenous species. One is the ready availability of either spawner or broodstock. The second is that the shrimp can be promoted as a distinct product -- Persian Gulf shrimp, rather than compete in the crowded black tiger shrimp market. The third is that it would be the most adaptable to the generally higher salinity Persian Gulf waters without having to depend on freshwater or brackishwater supply which is available only in at most 3 localities in Iran.
Which of the 3 major species in the Persian Gulf should the development focus on then? It appears with the present state of knowledge that the P. semisulcatus is the most promising. It is true that there is no worldwide interest in farming the species after experiments have shown it to be “slow growing”. But then it should be noted that the species was considered slow growing because it was always compared with the black tiger shrimp, probably due to their similar color pattern. Actually any other species now being raised can be considered slow growing compared to P. monodon. So why is China still farming P. chinensis, and Ecuador, P. vannamei? There is only one answer. Because they find it profitable. Thus the bottom line is the profitability of the venture not the relative growth rate of a species.
It is not possible to similarly consider P. merguiensis at this stage. While it is considered one of the commercially cultured species in Asia, in reality, there is little interest in the species among Asian shrimp farmers. For one, survival or recovery beyond a 3 month culture period, had always been found to be low. It is for this reason that Asian farmers sometimes refer to this species as the “disappearing shrimp”. It should also be noted that of the 3 species cultured in Kollahi in 1992,P. merguiensis had the lowest recovery and harvest. Even with such a background, more pond culture trials should still be conducted on the species.
The third and what is considered the “least important” of the 3 Persian Gulf species is the M. affinis. While commercially less important because of its small size, the species reportedly has a good local market in Iran. Its small size and lower price it seems may be more than made up by its hardiness and its ability to survive and grow even with minimal care and feeding. Among the 3 major species it is also reported to be the only one known to have spawners available almost year round. With such characteristic it would seem to be an ideal second or winter species. Conceivably after a first crop of P. semisulcatus, the pond can be stocked with M. affinis rather than left empty. Perhaps it can be sustained by natural food organisms with the pond productivity enhanced by fertilization. It has already been demonstrated in Kollahi that a harvest of 900 kg/ha is possible with this species. Work on the species should be continued.
Even if a species found in the Persian shall be propogated, there is still a need to organize a reliable spawner supply system. At present the pilot hatcheries in Bushehr and Kollahi simply contracts a trawler to catch spawners. It has been observed that the number of spawners that can be obtained with such limited operation is very erratic. Sometimes no spawner can be caught at all. Oftentimes the number that can be collected is less than what would be necessary to operate the small hatcheries at full capacity. Once the hatcheries as scaled up to serve hundreds of hectares of shrimp ponds it is evident that such limited operation will not be sufficient to supply the large-scale hatchery with the required number of spawners.
It is necessary for the present hatcheries to send out their own trawlers rather than rely on fishermen because shrimping is not allowed during the time they can operate. Shrimping is allowed only by late summer to early autumn depending upon the location in order to allow the shrimps to reproduce. Whether the shrimping should be partially opened during spring in order to allow more trawlers to be out in the sea and therefore improve the spawner supply situation is not an easy question to answer. It has been observed that the number of gravid females is higher during early spring but dwindles as the season progresses. It is necessary to closely monitor the reproductive stage of the shrimp stock so the peak period for natural spawning can be determined. It might be helpful to review the shrimp resource management system in other countries where shrimp fishing is important and which have good fisheries statistics.
Because the number of gravid females dwindle towards summer, it might be necessary to develop land based maturation system and integrate this as part of the hatchery. With maturation tanks the trawlers need not be limited to collecting Stage IV females, and the collection can be expanded to include all large shrimps. It is necessary at this stage to conduct some tests to determine whether or not it is necessary to perform eyestalk ablation to produce spawners. The P. semisulcatus is known to mature in captivity even without eyestalk ablation. Just the same it is necessary to obtain maturation and fecundity rates for captive broodstock in order to determine production parameters for planning and developing new hatcheries.
What has been demonstrated so far, whether for an introduced or a local species is the technical viability of shrimp culture in Iran. Aquaculture however is more than just being able to propagate and grow shrimps to marketable size. More importantly it should be demonstrated by actual culture trials in the field, rather than by pencil pushing, that the shrimp can be grown profitably. Determining profitability is also more than just subtracting the cost of the direct inputs such as feed from the expected export price. It should be well to remember that the small-scale shrimp farmers which Shilat hopes to generate will not likely be able to export directly but will have to sell their produce to a packer for processing and eventual export. In determining the profitability of a small-scale venture, it is the farm gate price which is considered. Only in large scale, integrated operation where the producer is also the packer and exporter is it realistic to use the export market price.
Normally in an area where shrimp culture is newly introduced, the price level for shrimps caught by fishermen would likely dictate the farm gate price. This assumes that a free market system is operational. In Iran, however, the buying price for captured shrimps is pre-set each year by Shilat which has a virtual monopoly of the shrimp trade. Under the present circumstances it is not possible to employ the usual tools for financial analysis to determine financial viability of a shrimp culture venture in Iran.
One possible approach is to compare the minimum price that a producer can sell the shrimps against the maximum price that a buyer such as Shilat can afford to pay for. From the producer's side, the minimum price the product can be sold will depend on production cost and a reasonable profit margin. From the buyer's side, the maximum price that the product can still be purchased will depend on the possible final market price based on trends, the cost of processing and handling and a reasonable profit margin. In order for the shrimp culture venture to be viable financially, the computed minimum selling price of the produce should be lower and at most only equal to the maximum price that the buyer is able to pay. If it is higher, the viability of the venture will be unlikely. In case the venture is found to financially not viable even after modifying the culture approach and assumptions, hard decisions will have to be made as to whether to proceed with the project on the basis of socio-economic and socio-political considerations. Needless to say actual production input and output data from the field will be necessary for such an exercise.
It is only with actual production data would there be a basis for determining a viable farm size. At present Shilat has simply mandated that the family farm size shall be 4 ha and the company farm size, 20 ha. More field trials are necessary considering that only one growing cycle is certain due to the pronounced climatic changes. The field culture trials should also include the culture of M. affinis as a second crop as mentioned earlier. The limitation imposed by the climate allows very little error and flexibility in the system.
The hatchery being envisioned in Mahshahr, and other hatcheries after it, will all be very large due to the short operating period possible. Even before their construction, a workable system to manage and operate these hatcheries should already be studied. It is inconceivable, due to the large number of tanks, to have one person personally supervising the feeding, changing of water, and cleaning of each tank.
One possible way of operating such a large hatchery is to decentralize its day to day operation by organizing the hatchery technicians and workers into independent production cells and service units. Each production cell shall be assigned a set number of tanks to operate. Each cell shall determine when and how much to feed, when to change water, etc. for the tasks assigned to them. The other units, such as algal culture, maturation and nauplii production, water supply system, and others, shall be operated as centralized service units to attend to the needs of the fry production cells. The hatchery manager's main responsibility shall be to see to it that all the service units are operating optimally and all the fry production cells are getting their supply of water, nauplii, natural feed, etc. He shall serve also as an overall troubleshooter and technical resource person for all the production cells and service units whenever necessary.
The present plan of Shilat is to immediately involve economically disadvantaged individuals in shrimp culture by distributing to them an operational shrimp farm unit. While this is commendable it should also be noted that the skills for shrimp culture is not something that can be acquired by just undergoing a training course. Considering that operating a shrimp farm is not risk free, there is a real danger of a high failure rate and therefore high degree of disappointment among the participants of such a program.
Perhaps it would be advisable to initially involve only the large companies who have expressed strong interest in investing in shrimp culture. Such companies can “afford to lose” and will have other sources of income in case of initial failure. An individual depending solely on the farm as a source of livelihood will go hungry with the lose of one crop. In fact instead of the present policy of limiting a company to only 20 ha, it would seem more productive to allow qualified companies to develop larger areas on their own and allow them to import their own technology if they so wish, rather than be limited to what Shilat can offer. Provisions can always be made on schemes for eventual smallholder participation beyond a certain farm size. The shrimp industry in Southeast Asia developed rapidly as a result of private sector initiatives in response to market forces with the government's role limited to largely providing the required physical and financial infrastructure.
The local people in an area will still be benefitted through such approach by being employed. Through their involvement as workers in the large commercial farms it is expected that they shall develop their skills without any financial risk on their part. It is these workers who can later be made the beneficiaries of a program to distribute ready to operate farm units under either government or private sector initiative. It can be expected that once the large companies start to make money, the workers and the ordinary people will not need any convincing to become shrimp farmers themselves.
