Indonesia is a large country so that this report is based only on areas where observations were previously made within the country and those conducted during this consultancy. These include: (i) Java particularly the Jepara, Central Java project and the Inland Fisheries Institute at Bogor, West Java; (ii) Irian Jaya (based on previous survey); (iii) Kalimantan - three provinces of four, namely: West Kalimantan, South Kalimantan and East Kalimantan were surveyed; (iv) Sulawesi- two provinces of four were surveyed, namely: South Sulawesi and North Sulawesi; and (v) Sumatra - two provinces of eight, namely: Jambi and South Sumatra including Bangka Island part of last named province were surveyed. The projects in Java are established government research and training institutions with emphasis on aquaculture.
The provinces visited in the outlaying islands showed rich fishery resources and wide areas are available as existing and potential sources of aquatic products. Aquaculture industries vary greatly from fairly developed in Java and South Sulawesi to underdeveloped but with great potentials in the rest of the provinces.
Specific observations were made on engineering aspects in this survey. In general this aspect has not been given adequate attention and there is large scope to improve production from existing aquaculture installations through properly constructed projects. New projects under planning need proper layout, design and construction specifications in order to avoid future management problems, accelerate development of the industry and maximize production to establish economically viable industry.
The Shrimp and Milkfish Culture Applied Research and Training Project at Jepara, Central Java is an FAO/UNDP-assisted project. The project is a 50-hectare site used for building experimental ponds, a campus for office, laboratory, hatchery, staff housing, and dormitory and training buildings. Duty travel to this project was mainly to render assistance on equipment particularly the water pumps which are needed for proper pond management. The specific observations on the project's equipment are enumerated in this report (ANNEX 5).
A visit was made at the Inland Fisheries Research Institute Laboratories and experimental ponds at Bogor, West Java. Of interest in this station is the work being undertaken in testing pesticides used in ricefields and their effects on species of fish raised on freshwater ponds.
In area this is the largest province in Indonesia but it is also the most sparsely populated. In general the province has rich fishery resources which are still underexploited. Potential export crops like tuna and shrimps and prawns abound. Aquaculture has been initiated on small pilot scales in freshwater. Several freshwater hatcheries mainly for carp and tilapia have been established specially in isolated upland interior areas. It is noted, however, that many of these hatcheries are too small in size to be consequential (some only few hundred square meters most less than half hectare). The Freshwater Demonstration Fish Farm, Hatchery and Training Centre at Sentani has adequate area and is well suited as aquaculture training centre. Fish cage culture for carps has been initiated successfully at nearby Sentani Lake.
The province has extensive inland freshwater and tidal mangrove swamps. Brackish water ponds in mangrove areas can, however, be suitable only in the western half of the province where the tidal range is favourable for tidal pond management. The extreme northeast has very narrow tidal range while the extreme southeast has very narrow tidal range while the extreme southeast has very high tidal fluctuations which makes brackish water pond management very difficult.
This province is endowed with rich fishery resources - both marine and inland which are still underexploited. The population is still sparse but the province has some sites which has been earmarked for transmigration from the populous regions of the country so that the population may tend to rise more rapidly.
The province has extensive inland waters estimated to be about 2 million hectares. This is mostly along the Kapuas river system which extends to over 1000 km in length and with marshes and lakes in its upper stretches. The tidal mangrove areas are also extensive estimated at about 100 000 hectares.
Although there is no immediate necessity for aquaculture development, initiation of both fresh and brackish water aquaculture is a farsighted move that has been taken by the Provincial Fisheries Service. The potentials of fish production from this source is almost unlimited for carps, and other cyprinids and giant prawn in freshwater and for penaeid shrimps, mainly Penaeus merguiensis, and finfish like mullet or milkfish in brackish waters. Cage culture utilizing woven rattan with wooden frames is practiced in the lakes at the northeastern part of the province. Two provincial freshwater demonstration fish farms and hatcheries are strategically located in the upland interior towns far from the seacoast or inland waters.
The establishment of a brackish water demonstration fish farm mainly for Penaeus merguiensis has been initiated in Mengacek, Mempawah sub-district in this province. The area is about one hectare and has the following features:
Gate construction - too large and not well-installed so that water is seeping through the sides and bottom.
Pond quite empty of water except for the deep portions along the dikes. This is an indication that the pond bottom is slightly elevated.
The pond layout can be revised and expanded. The present layout and suggested revision are shown in this report (ANNEX 6).
With regards to fisheries and aquaculture similar conditions as those of West Kalimantan exist in this province. The marine and inland fishery resources are still largely underexploited. Present production is predominantly from inland waters. There is limited local market and production is not encouraged due to lack of transport and distribution facilities. With heavy rainfall, extensive tidal mangrove swamps and inland water areas the development of fresh and brackish water aquaculture has large potential. The provincial fisheries service has initiated brackish water demonstration fish farms at Laut Island and Pegatan Regency in the southeastern coast of the province. The service also maintains a number of freshwater fish hatcheries.
The following observations were made in this province:
A mangrove swamp at Takisung, 70 km from Banjarmasin was surveyed. The river water was very turbid and silty; salinity is 0. ppt. Prevalent trees are Excoecaria agallocha, a few Avicennia species, and some Nypa sp. and “butabuta” (alipata). The mangrove land elevation ranged from 2.2 to 2.4 m; the maximum high tide range is up to 2.5 m. Portions of the mangrove were being cleared for rice plantation. The mangrove area in the locality is estimated to be from 60-80 ha.
The Barit River near its mouth was surveyed by speed boat. Though most of the areas along the rivers and recently constructed drain canals have been converted to rice and other plantations, yet the water table remains shallow. This would allow extensive development of freshwater ponds either by excavation or pumping should such projects prove economically feasible in the future.
There is likewise an equal abundance of inland and marine fishery resources in East Kalimantan as in the other two Kalimantan provinces surveyed. As traditional artisanal fishing methods still prevail, much of the resource is perhaps underexploited. The province has a network of large rivers with extensive lakes, marshes and floodlands along the river courses. The coastal zones have extensive tidal mangrove swamps.
The total fish production in 1974 is 43 294 tons consisting of 19 429 tons from inland fisheries and 23 865 from marine fisheries. About half of the produce or 20 983 tons is consumed locally while the rest are exported in other islands within the country (interinsular) or processed as dried fish. Tuna, shrimps and prawns are the main exportable species while there are a large variety of others consumed locally. The rivers are rich fishing grounds for Macrobrachium prawn.
Aquaculture in both brackish and freshwaters has been initiated in this province. Being a transmigration area and a place for good number of mix foreign population, aquaculture crops find ready market. Transmigrants from Java and Sulawesi also furnish skilled labour and consuming population for aquaculture. Some 145 hectares of brackish water ponds or tambaks and 700 hectares of freshwater ponds or kolams producing about 300 tons have been reported. The heavy annual rainfall and rolling terrain in most parts of the province and the presence of a network of rivers favour the extensive development of freshwater aquaculture. The coastal zones abound with tidal mangrove swamps awaiting development into brackish water ponds. The tidal range along the coasts of the province is suitable for proper pond management and the elevation of some of the swamplands visited are suitable for this development.
It was observed however that the initial pilot demonstration areas put up by the Provincial Fisheries Service are too small for the purpose. The one put up at Handil Village in Sampoja sub-district is hardly 0.5 ha. This is too small for a viable economic project and could make a poor demonstration of a good layout for family size projects. Viable economic projects of at least 5 hectares or more should be demonstrated. Also, proper layout and adequate construction specifications are not being followed. The dikes are observed to be too small and too steep and the dike path have not been cleaned of trees, stumps, roots and other organic matter. Puddle trenching specially for the main dikes is not practiced and the soil used for diking is not cleaned of undecayed organic matter. Projects constructed in this manner are usually beset with numerous problems of management after they are completed.
Another observation is that the province is rich with oil and forest resources. The exploitation of these resources are in progress and will still increase in the future. At the same time there exists in this province many valuable resources both for local consumption and for export. This include skipjack tuna, penaeid shrimps from marine and coastal waters and giant prawns from the rivers. The greater portion of the coasts also are good sources of Chanos fry needed for seeding the tambaks to be developed as well as those existing in nearby islands of Sulawesi and Java.
The fisheries of this province is better developed than many of the provinces in Indonesia. The open inland waters are limited in area consequently production from this source is low. Its production from marine fisheries is big reported to be over 90 000 tons and is among the highest and aquaculture specially for milkfish and shrimps in brackish water ponds are comparatively higher in production than other provinces. The brackish tambaks are bigger holdings than those in Java and bigger area of individual pond compartments (up to 20 ha each) are more used. Instead of production average of 400 kg per year, South Sulawesi tambaks produce 600 kg (range of 400 to 1000 kg/year).
Freshwater aquaculture is also practiced. There are 328 ha of freshwater ponds and 1 665 ha of ricefields used for fish production reported for the province.
The layout of South Sulawesi tambaks appear to be better designed than most areas in country. Because of the importance of this industry in the province, the industry is subject to financial assistance from funds obtained from World Bank loan. Even marginal lands that are somewhat elevated from the tide range are being reclaimed for brackish water tambaks. Milkfish and salt water penaeids have good local market and the latter is an export commodity. Penaeus monodon or “udang galah” is the main tambak species while Macrobrachium rosenbergii or “udang galah” is harvested from the rivers of province. Processing plants joint venture by government with foreign concern are engaged in processing and export of these products.
The World Bank funding requires better designed and constructed ponds. This is done through technically supervised credit assistance. In addition to private borrowers the provincial government is also required to put up demonstration sites in fishpond development centres.
The demonstration fish farms which are now under construction show dikes with more appropriate slopes than previously practiced. The layout appears improved. However there is a tendency to build experimental type layouts instead of commercial ones or where small equal-sized ponds instead larger ones are used. This causes large losses in space for dikes instead of for production. It was also observed that the rule of independent water control for each pond compartment is also not strictly practiced inspite of the provision for water supply canals.
In actual dike construction the digging of central puddle trench and compacting the soil in the process is not strictly practiced. While the dike slope looks good, future problems in pond management due to seepage and leaks in the dikes are likely to occur with this system of construction. A number of the wooden gates, both main as well as secondary, were observed to be not well constructed and installed so that seepage and erosion through these structures occur. Reinforced concrete gates are not commonly used and mechanized construction has not been observed.
The province has a narrow tidal range, an absolute range of 2 m and normal daily range of 1 m. More extensive use of water pumps such as that by an association of fish farmers in Janeponto Regency has proved to be advantageous. This progressive group of fish farmers operate an area of 80 ha. This group has in operation two 12" Ornel channel pumps (low lift-high volume propeller pump). Pumps have to be used due to high land elevation in relation to the tide especially during the months of July, August and September. The group use chemical fertilizer in the ratio of 1 N to 2 P from 100 to 150 kg of urea (for N) and triple superphosphate (for P). Production averaged 600–800 kg/ha/ year of combined milkfish and shrimps.
The main feature of the fisheries of this province is its rich marine resources of tuna and shrimps which are valuable items for export. The inland waters are limited but abound with valuable resources like the giant freshwater prawn and eels. Various species of carp and other cyprinids and tilapia are raised in freshwater ponds and in selected ricefields.
Inspite of the maritime condition of the country with its long irregular coastline, the liking for fish produced from freshwaters such as the carp is a favourable development in this province. The raising of giant prawns and eels, both of which can be obtained from rivers in this province, has good potential. There is limited area for expansion of brackish water aquaculture; the province has only about 10 000 ha of mangrove swamps of which only 5 000 ha are available for development.
The existing freshwater fish hatcheries are small in area and their present locations are fast being overrun by new developments in agriculture and urbanization. The presence of numerous springs and the rugged terrain in greater parts of the province and supplemented by heavy rainfall favours the development of freshwater aquaculture in this area.
This is a province in central east Sumatra. It is wide in area with sparse population and rich in fishery resources which apparently is still underexploited. Fish production come mainly from both marine and inland waters. There is limited amount of production from aquaculture; about 90 tons.
The capture, holding and exportation of aquarium fish is an economic industry in this province. From 800 000 to 2.5 million aquarium fish are exported from Jambi each year from 1968 to 1973. Subsistence fishermen while catching various species of food fish in the extensive network of inland waters also catch and trap aquarium species. The major species that command good price in the market are Boitia macrocanthus mainly and also Balantiocheilus melanopterus, Epalzeorhynchus kallopterus, Labeo chrysiophetakadion, Puntius tetrazona and others.
The catch is collected by middlemen who acclimatize and grow the fish from fry to fingerlings or adults. These are then exported to Jakarta or directly to Singapore. Depending on the kind and size, the fish sells at Rp 10 to 100 per piece.
For freshwater ponds, the officers in government projects as well as private pond owners claim that there is deficiency of water supply for the whole year. Because of this, the ponds are laid out so that water from one pond can be drained and used in a next lower pond utilizing gates or pipes. There is, therefore, no independent water control. Prolonged use of the water and stagnation seem to be characteristic and the surface of the water in the pond is oily and have a characteristic color perhaps showing the presence of iron compounds. There is presently an outbreak of Lernaea infestation in the area and the series arrangements of the ponds favour the rapid spread of this parasite.
The use of tube-bored medium-deep or deep wells is not practiced and there appears to be no attempt to find out their possible use. Water from this source which can be very clear and clean is good for use in hatcheries as well as for production ponds.
Due to lack of funds, the planned government brackish water demonstration farm is very small, less than 1 ha. Site selection in mangrove area where the land elevation is ideal with regard to the tidal fluctuation is observed to be inadequately considered. In the site now being started the elevation is apparently high.
Experimental layout characterized by small ponds some less than 1000 m2 is being adapted. This is not a good pilot demonstration of a commercial type tambak. For a family use, units of at least 5 ha are advisable as viable economic size. Such areas can be constructed starting with one strategically located main gate which should have adequately large and firm main dikes with proper slope. Without even clearing the inside trees and other vegetation, operation of the enclosed area for production can be started. The leaves of the trees within the site will fall down when the pond is flooded and add to the fertility of the pond bottom. Gradually during the years inside vegetation are cleared until fully cleared coupled with the building of necessary pond compartments and levelling.
Thorough cleaning of the path of the dikes of roots and organic matter is not given adequate attention. Likewise the excavation of puddle trench on the central core of the dike path especially for the main dike have not been observed. This will result in numerous seepage problems in the future which will make training and drying of ponds impossible.
South Sumatra is another province with rich fishery resources that can still take more intensive exploitation. The main bulk of the fish production presently comes from inland waters followed by the marine catch. Although aquaculture has large potential very limited development has been done in this industry.
Existing fresh water ponds visited show that water supply is conveyed by pipes or shallow canal from one pond to another in series from the highest level pond to the lowest. Although this system may result in economy of the water supply which may be limited in some sites it is however not conducive to good fishpond management as there is no independent water control for each pond. This will present difficulties when you want certain ponds filled or drained. The use of pipes or open canal along the perimeter dike may serve better with each pond having independent drainage exit which can be used only as needed so that a pond once filled can make use of its water as long as it remains to be of good quality.
No brackish water fishpond or those that will depend on tidal water supply for watering was seen but it is observed that the greater portion of the tidal lands along the Musi river system near Palembang are too elevated to be reached by tidal water, and the tidal range is quite narrow in the area (01 to 19 dm or about 2 m absolute range and 06 to 15 dm or about 1 m normal daily range). Preliminary determination of the sites visited in Upang area of the Musi River and along Telang River show elevation of the swamps at 08 to 15 or even as high as 20 dm so that to build tidal fishponds here will require excavation of as much as 1/2 to 1 meter deep. It appears that the extensive watershed area originating from the Bukit Barizan mountain range brings big volume of freshwater during the rainy period of the year which greatly influence the Musi River system area. Tidal fishponds seem to be inadvisable along this river system. Location of sites along the smaller river systems with more limited watersheds in this province is suggested.
The island was specifically included in this survey because of the special condition of its fisheries. This island and neighboring Belitung Island are the centres of tin mining in Indonesia for many years. These islands are therefore dotted with numerous abandoned tin mining pools of varied sizes and with either fresh or brackish waters.
Development of this type of water for fish production is being envisioned. The rivers of Bangka Island abound with population of Macrobrachium rosenbergii which is presently exploited to the extent that the local market can absorb. There is also abundance of penaeid shrimps specially Penaeus merguiensis, the juveniles of which can be used to stock brackish water ponds. There is no verification of the presence of Chanos adults nor fry along the coastal waters of Bangka Island. However, it is reported that this highly economic species exists in Belitung Island, which needs to be verified.
Bangka Island also has extensive areas of tidal mangrove swamps suitable for development into fishponds. Some development in this work has been started both by the provincial and district fishery service but with limited funding support. A new government demonstration fish farm visited showed defective main gates, elevated site and inferior layout. Better construction of gates and improved layout were suggested at spot. Proper demonstration by the government project is very essential specially because private parties are now starting with their own projects.
The extensive mangrove forests of the Peninsular Malaysia are on the west coast. The bulk of the marine capture fisheries are also along the west coast especially Perlis (Langkawi) and Perak states. Generally too, the west coast of Malaysia has mangrove swamps with lower elevation than Johore in the south and in the states in the east coast. The only sizeable swamp or mangrove area in the east coast is in the southern end of Trengganu around Chukai, Kemaman and Kerteh.
For experimentation at minimal expenses, the elongated brackish water area or lagoon located about 20 km south of Kuala Trengganu can be converted to ponds using pipes laid to get clean, new sea water from the sea directly. Electricity in this locality is available. This water channel is from Merchang to Pulau Kerengga. ANNEX 8 shows sketch of suggested development for this site. If this proves feasible, perhaps a 15–30 ha production demonstration and experimental ponds can be set up at south bank roadside, after the bridge going south at Kuala Kerteh. (See Figures 8 a, b, and c ANNEX 8 for suggested layouts).
There are some shrimp trapping pond in the country aside from these. There is hardly any brackish water aquaculture going on in the Malaysian Peninsula, although some private people have begun small efforts and actually started to work on some pond construction. This appeared to be too small in area and seems in great need of expert advice.
The specific findings in the different sites of the country surveyed follows (ANNEX 7).
The only mangrove area in Penang State is a long mud flat on west side of Penang island. Three points of this long mud flat were surveyed and it was found that there are possibilities for their utilization but perhaps at a later date as there seem to be better areas.
At Perlis state, there is not much mangrove on the mainland proper. However, there is a very extensive Rhizophora mangrove at Sungai Tuba in Pulau Langkawi, but because the area is very sparsely populated and is about 3 1/2 hours away by passenger boat, the site is not recommended for any immediate development but can be reserved for future use. It might be worth mentioning that at Kuala Perlis there is a cooperative that has pooled M$5 000 (US$2 200) for the development of a seaside mangrove estimated to be about 3 ha. The plan is to culture swamp crabs and sea bass. The owners are encouraged by traders from Thailand who do some fish trading in Perlis. It is reported that the Perlis cooperative may be supplied of sea bass fry from Thailand where it is reported that this species is now being spawned under controlled conditions. The area intended to be developed by the cooperative is rather high in elevation in relation to the tide, nevertheless, the soil is good for diking; and the prevalent vegetation is Avicennia sp. and not very dense. The crab and sea bass culture can possibly do well due to much available and seemingly unutilized cheap trashfish which can be used as feed. Kuala Perlis has a big fish landing area for trawlers. Although there are not too many available mangrove for expansion, yet the results of this cooperative venture can have a great impact as this area is very thickly populated by fishermen. Also, many fishermen come here from other mangrove areas. The government would do well to support and guide this modest effort as it may be the basis of a beginning of development in Pulau Langkawi or in Kedah and other places of Malaysia in the future.
Tanjong Dawai in this place seems to have the most mangrove (predominantly covered by Rhizophora with few Avicennia species and near ideal elevation with good water supply and quality. Because of the many fishermen in the area, the socio-economic impact will be great. Soil quality is generally good and water salinity at the time was 20 ppt. There is a pond (about 5 ha) under construction by a Chinese which is about 30 percent done. The perimeter dike is already completed. The pond has wild stock of shrimps in it and shows a good growth of benthic algae. It is in this area that a pilot project may be set up for the west coast (ANNEX 8 shows a proposed layout). A new fish landing is being constructed by the government and trashfish are available from the many fishermen and fishing boats in the area.
This state has large mangrove swamps with Rhizophora as the prevalent mangrove species. The soil has a very high content of organic matter. Although natural mangrove land elevation in a bit high, the area has plenty of potential. There are several thousand hectares that can be converted to fishponds especially at Larut Matang, Sungai Kechil and Selinsing Islands. In Telok Rumbia, there remains about 400 to 600 hectares of good predominantly Avicennia mangrove. About 1 000 hectares former mangrove has been drained by the Department of Irrigation and Drainage (DID) and given to palm oil and coconut plantations. The lower portions of these plantations are still reached by high tides. Extensive mangrove are also available in Sungai Kerang, Sungai Jarom Mas and around the fishing villages of Bagan Pancor and Sungai Tinggi.
Aside from high organic content of soil, other factors indicate that there is a bright future in aquaculture in these areas of Perak. A 10 or so hectare demonstration/experimental pond can be set up near the fishing village of Bagan Pancor. The 200 families of the area are on subsistence fishing and may be receptive to new ideas.
The mangrove around Kuala Selangor are very marginal and elevation is much too high. Most of the mangrove areas have been drained and converted to industrial estates. Pollution is a growing problem.
In Sungai Lukut is a shrimp trapping pond of the Singapore type. According to the manager, they are doing very poorly financially due to poor catch. The natural land elevation is much too high and only the canal from diking excavation has water.
This project has an extensive freshwater pond complex at Batu Berendam. Because of the unstable foundation, their two intake pipes in their primary pumping station have been giving them problems. It has been noted that the area between the pump house and the supply creek have been shifting and the concrete pipe support have lowered considerably causing misalignment and breaking of the pipes. Solution offered is for them to drive 3 to 4 pairs of concrete piles on each side of the intake iipes and these piles then be made to carry the pipe weights (ANNEX 9 and Figure 9 a).
At Sungai Rembau, a Macrobrachium pond consisting of 9 compartments of ⅓ of a hectare each has been established. It is a fairly new pond constructed out of predominantly nipa mangrove with only about 50 cm water depth. Since the area was quite elevated to begin with, the dikes between the ponds were wide and high the crown being 4 to 5 meters. One can right away notice that there is no centralized water supply and discharge system. Water is passed from one compartment to the other through 10" (25.4 cm) asbestos pipes. It is a very expensive construction and the caretaker reported no success inspite of the ponds having been constructed for the very reason that the area abounds with natural stock of wild Macrobrachium.
In Sungai Linggi, there is another prawn catching culturing pond under construction that is nearing completion. However, the situation is such that the natural land elevation is too high and residual pond water is only at the canal where soil has been dug for diking purposes. The soil is poor and of high organic content. Prevalent area vegetation is nipa.
There are a number of existing ponds in Johore Bahru. Most of them are shrimp trapping ponds. Another practice observed was that of crab fattening pond operations. This consists of buying soft-shelled crabs that are unacceptable in the market and quite cheap. Crabs are then fattened in 1/2 ha ponds with intensive feeding of trashfish, poultry refuse, etc. and selling these after a month or two. The business run by Chinese crab farmers is doing well inspite of the usual 30 percent mortality. These are concentrated at the Kampong Telok Jawa.
Sungai Chukoh Serkat is a large-sized shrimp trapping pond. Investigation showed that the site elevation averages from 2.6 to 2.9 meters. The trapping ponds are not doing well financially, hence they are excavating more to widen the watered area for the culture.
Plentong Tebrau. There are better trapping ponds visited in this area. The water quality is better than at the proposed government project site at Gelang Patah. The land elevation is also a bit lower at 2.6 to 2.8 meters. As a matter of fact, if it is decided that the station must be at Johore Bahru, this site can be considered as an alternate for the Gelang Patah site. It has very good accessibility, too. A reevaluation of the Gelang Patah proposed site is ANNEX 7. Pollution is a growing problem in Johore Bahru.
Generally, the predominantly trees are Rhizophora; soil is poor and mangrove not too extensive. Water quality, however, is generally good.
Kuala Penarek has a big river but mangrove along the sides are too narrow for any good development at present.
Kuala Petri - Soil is quite poor. Mangrove is also narrow along the river. Salinity is good. A good demonstration pond can be made in this area but because of its small total available area, the impact can be quite limited.
Kampong Ibai is in many ways similar to the characteristics of Kuala Petri.
Kuala Kerengga and Merchang. Here is a rather unique formation. There is a long pond or water channel about 7 km long, about 1.3 meters in depth and 60 to 70 meters across. This channel is separated from the open sea by a high sandbar about 70 meters wide. The channel bottom has a good; soft sediment formation 20 to 30 cms thick over the sandy bottom. Here pilot culture tests may be set up at minimal expense. It is located at roadside, electricity is available and water quality is good. (Sketch for proposed utilization of area is in Figure 8 c ANNEX 8).
Kuala Kemaman. Here are extensive mangrove, although the salinity is quite low Kemaman has a big freshwater river. However, for milkfish and mullet culture, it may not present too much problem but may not be very suitable for penaeids.
Kuala Kerteh. This area seems best suited for a demonstration area if one would be set up at the east coast. It is highly accessible and there is room for expansion. Also, it is right by the main highway so the impact would be great.
Kampong Chukai and Sungai Datu. These are good reserve areas for future development. Mangrove trees are Avicennia and Rhizophora species. Soil elevation needs only limited excavation and salinity in ponds can be controlled by timing water intake with the tide. Soil quality is all right.
Sabak and Tumpat in Kelantan have very narrow mangrove along river edges. Soil is very sandy.
Although some small ponds may be profitably constructed and operated later, the area may have to wait till species and culture method shall have been fully worked out. One bad feature of the Tumpat area is the seasonal flooding reported to be quite frequent.
The Philippine scene mainly consists of brackish water pond operations; there is no fresh water pond culture to speak of. In 1973 there were 176 000 ha of developed area producing 100 000 tons valued at about 400 million pesos.1 It has been roughly assessed that there still exists a potential of 400 000 ha for future development. The rate of expansion continued to be quite rapid, estimated at 1 000 to 4 000 ha per year. This industry exists in all the bigger islands of the Philippine archipelago.
The maximum range of tidal fluctuations in the country is 2 to 3 meters with normal daily range of 1.5 m. This is ideal for management of brackish water ponds provided the sites developed are within suitable elevation.
Due to the high cost of development (present average 8 000 pesos/ha) the trend was toward intensification to increase production from existing areas. The rapid rate of inflation brought about by the worldwide oil crises, however, dealt a blow to this trend. Needed inputs such as fertilizers, supplementary feeds, pesticides, etc. became very costly.
Although very confined in location, a recent new innovation in the industry is the development of pen culture mainly for milkfish in a lake. The pen consists of nylon net enclosures with bamboo frames set up in a relatively shallow eutrophic lake (1.5 to 3 m deep), the Laguna de Bay lake in Luzon island. The pens vary from 1 ha to several ha in area with production average of about 5 t/ha/year. It is estimated that there are up to 10 000 ha of developed fish pens. There is a tendency to overstock and if this occurs with the recurrent decay of algae blooms in the lake wholesale mortality takes place.
1 US $ equals 6.50 Philippine pesos in 1973.
The governmental fisheries activities of Singapore centers around Changi Point Fisheries Complex.
Most of its suitable and available mangrove areas are utilized as shrimp trapping ponds of which there are 1 265 acres (512 ha); each farm unit ranging from 1 to 50 ha.
Pollution is a growing problem of the country due to its being an industrialized nation and because of its strategic location as a commercial port. It also has an extensive petrochemical processing complex. The maximum or absolute tide range of Singapore is 3.6 meters. The normal daily range is 2.1 meters which are favourable for brackish water pond management.
The fisheries work of Singapore is mainly directed from Changi Point where there are activities on:
In this Complex the main building houses the administrative offices, library, laboratory and supply rooms. Adjacent to the main building is the hatchery where there is a series of tanks with centralized aeration and water supply and drainage system.
The Complex has another two-storey building which serve to house larval rearing tanks and aquaria and to store equipment for field operations. The first storey which is unwalled have concrete rearing tanks and portable fiberglass tanks used for spawning and rearing of larvae and juveniles of Macrobrachium rosenbergii and some finfish. Part of this floor is also used to store nets, boats, outboard motors and other equipment for field activities. The second floor is used for offices of biologists, accountant, and as field laboratory and supply storerooms.
Changi Point staff also run experiments on net cages in the Singapore channel nearby this station. The cages are placed inside a fence of circularly arranged palm trunks staked into bottom for protection.
The main aquaculture activity in Singapore as far as area involved is concerned, is in shrimp trapping pond operations.
It perhaps can be considered culture in a way because the shrimp juveniles are allowed into the ponds through the gates at high tide and these grow in the ponds and are caught when they are large enough to go with the water being drained from the ponds. However, the pond operator does nothing more than operate the gates. There is no activity directed to growing of food in the ponds, no fertilizing, no feeding, nor attempt at levelling the enclosed area.
Upon suggestion that shrimp trapping ponds be developed into real culture production ponds of either finfish or shrimps, the operators expressed reluctance. The reasons given are the following:
a) Massive reclamation projects are underway. The Government cannot guarantee the continued operation of the area which may be developed. Due to the rapid urbanization of Singapore many ponds are filled and converted to industrial or residential places.
b) Development expenses are too high. Singapore has one of the highest standards of living in Asia hence services are expensive.
c) Water pollution is also one of the big concerns of trapping pond operators.
d) There is need for more information as to:
This project (name given by previous owner) used to be a sand quarry which has been converted into a resort. The Government has recently acquired the area to be used for brackish water aquaculture experiments and demonstration.
The area is a little over 3 ha with the pond bottom varying in elevation by over 3 meters. It has a series of resort buildings around the pond and a system of wooden pathways and building in the pond itself. The area is totally fenced by barbed and cyclone wire.
At present, several experiments are being run in the pond. There are Chanos in cages, Macrobrachium in net enclosures. Some mullet and tilapia which may have entered accidentally can also be seen swimming about. At the time of visit, water was healthy dark green with salinity at 20 ppt.
The survey in Thailand was confined to the aquaculture centres along the Gulf of Thailand not far from the Bangkok area. Here extensive low-flat lands with both brackish and dreshwater conditions exist. Aquaculture has developed for a number of the more desirable species including Penaeus spp. (mainly P. merguiensis) for brackish waters and Clarias spp. Macrobrachium rosenbergii, Tilapia nilotica, and common and Chinese carps for freshwaters.
Tidal characteristics in the Gulf is narrow; 2 m absolute annual range and 1 m or even less average daily fluctuation.
This is an assisted project which is being renovated for the culture of penaeid shrimps mainly, Penaeus merguiensis. The objective is to excavate the site of about 70 cm in order to have a water depth of 1 to 1.2 m. It is intended to accomplish this by mechanized means either by excavator or with motor-driven high pressure pump by jetting.
The site is very open and much exposed to sun and wind, the rate of evaporation in the area can be very high, estimated to as much as 120 tons/ ha/day.
Due to the nature of the soil seepage through the dikes after the construction can pose a problem. The soft consistency of the soil can also cause difficulty in forming the dike, maintaining proper slope and preventing its getting back into the ponds.
Lampak-Bae, Ban Dam district was visited in this province. The general elevation of the land at site is high ranging from 1.7 to 2.0 meters. Due to this situation coupled with the limited tidal fluctuation and high rate of evaporation brackish water ponds require the use of pumps to maintain deeper water for shrimp culture. The soil is young formation consisting of hardened mudflats or silt. Although shallow (15–25 cm deep), the water quality is good resulting in good growth of natural shrimp food. It is observed that there is continuing abundance of natural population of shrimp postlarvae and juveniles.
Pumps especially of the push or propeller type are extensively used. There is a trend to use larger units with higher pumping power. Reconditioned diesel truck engines are commonly used with horsepower ranging from 50–300 HP. Currently most of the pumps used are from 2 500 to 4 000 RPM. Though more water can be pumped in with these powerful pumps it is reported that only about 20 to 35 percent of the shrimp postlarvae survive during pumping.
This is a brackish water fish farm station with an area of 9 ha. The soil is sandy and growth of natural fish food is poor. Milkfish culture is being demonstrated but this species is not widely accepted in the country; only 30 ha are developed in this area. As in Petchaburi the ponds have shallow water and pumps are used.
Milkfish fry are available along the coast during certain seasons of the year. It was observed that for catching fry small dip nets are used instead of bigger sienes or fry traps such as those used in the Taiwan, China and the Philippines.
This is a government project in the process of development. It is located in Bangpakong, Chachoengsao province some 75 kilometers from Bangkok. The site covers an area of 15 ha; hatchery, rearing tanks and ponds, office/laboratory building, housing for personnel and facilities for water supply, aerator blowers, electricity, etc. will be provided in the site.
Hong Kong has some existing installations for aquaculture but the area for possible expansion is quite limited. The activities in this industry are varied and likewise are the concomittant engineering problems.
This station has been working on the spawning of Chinese carps (silver, bighead and grass carp). Good success was attained with silver and bighead carps but grass carp will require further work; some 1.6 million fry were produced during the 1973–74 season. The studies on stocking rates using polyculture of Chinese silver, bighead and grass carps with common carp and mullet are being continued and a report on this work is expected in the future.
The station has some problem of flooding and was reported to have been flooded in recent years - 1971, 1973 and 1974.
This area appears to be an ideal place for aquaculture operations as shown by the high yields in the intensively managed ponds in this site. A good planning scheme to consolidate an orderly development for the whole area can greatly increase the production, resettle a number of families from the congested areas, leave ample space for conservation purposes, facilitate drainage and reduce flooding. It was observed that the kind of soil and elevation of the land are suitable for pond construction with minimal expenditure. Pond projects of family size units can be put up for fish production in this area. A government decision has to be made to utilize this site or at least a part of it for intensive aquaculture.
The culture of marine species using floating cages was started in Hong Kong in 1970 with encouraging results. The species used are high-priced marine species. In a survey made by the Department of Agriculture and Fisheries in 1973, it was found that this system is practiced in 7 districts using 460 units consisting of 2 076 cages with an estimated 260 tons of fish under culture during the period. The species used are red grouper (Epinephelus akoara), mud grouper (E. brunneus), yellow grouper (E. awoara), red pargo (Chrysophrys major), white bream (Mylio berda), yellow-finned bream (M. latus), mangrove snapper (Lutjanus argentimaculatus) and Siganus spp.
There is no standard size or form of the cages and in many cases, any handy material that can be available and made used of like synthetic nets of varied meshes, oil drums, cheap lumber, wire netting, styro foam nets or wooden slats with floats of drums, wooden rafts or other materials. The sizes used are 8' × 6' × 6' (2.4 × 1.8 × 1.8 m), 12' × 10' × 10' (3.7 × 3.0 × 3.0 m) while a few large ones may measure as much as 40' × 20' × 10' (12.2 × 6.1 × 3.0 m) in dimension. Data on the production of these cages has not been definitely assessed but it was estimated at the time that the set cages may be capable of producing as much as 10 000 tons per year. If the initial results will be favourable the practice is bound to expand.
In cooperation with the Public Works Department, the Au Tau Freshwater Fish Culture Station has started experiments on the use of sewage waste water for fish culture utilizing Tilapia mossambica and Clarias fuscus. This aquaculture activity together with duck-cum fish culture are some of the ways used to utilize and manage organic wastes and recycle nutrients in the environment. These attempts are important to counteract unfavourable effects of aquatic pollution in this area.
