Fisheries Research and Development Centre, Jakarta
Shrimp farming in Indonesia falls into two categories: traditional and intensive. Both systems still face technical constraints. In traditional system, the constraints include the following: layout and construction since the ponds used are usually old unmodified tambak for milkfish; generally thick silt and mud layer on the bottom; inadequate depth resulting in high daytime temperatures; difficulty in bringing in inputs and transporting harvests out due to poor accessibility; high costs of shrimp fry due to highly seasonal stocking pushing up demand and therefore price; inadequate working capital since most of the traditional ponds involves small farmers. To overcome these constraints there is a need to improve the general layout and construction and to encourage cooperative ventures between large companies with capital and the small farmers.
Intensive farms likewise have their own constraints. These are: site selection often based purely on price of land and accessibility; poor design in terms of dikes and drainage systems; installation of too many bamboo catwalks for feed distribution which hampers water movement; faulty layout/construction of pond bottom canals; inadequate and poor pond preparation; extremely high stocking density; poor acclimatization of fry prior to stocking; and water quality during rearing not at optimal levels. To overcome these constraints there is a need for intensive farms to proceed with caution so as to prevent unnecessary loses.
Extensive shrimp culture in Indonesia began in 1964. Intensive culture began much later in 1985 – 1986 and has rapidly developed since then. This was possible due to the following reasons:
Because of the rapid rate of development of the intensive farms, supervision in the opening of new ponds has often been inadequate causing problems to emerge later. In general proper technical procedures in pond development were not followed. In order to avoid undesirable consequences, steps should be taken to thoroughly solve these problems.
This paper focuses on the technical problems in intensive shrimp farming which are often encountered in the field. The author hopes that shrimp fry producers as well as shrimp growers will continue their activities with greater caution so as to avoid loses.
2. TRADITIONAL AND EXTENSIVE CULTURE
2.1 Site Selection and Design
In general, traditional and extensive shrimp culture are conducted in tambak previously used for milkfish almost without any modification and are characterized by inappropriate layout, shape and size. Supply and drainage uses one canal that is characterized by being very long and crooked, as well as being small and shallow. Usually the primary supply canal is made from, and is in the shape of, a river or creek which originally was big and wide enough. But pond developers along its length, from time to time, tend to push their main dike farther into the river until the originally wide channel becomes narrower and narrower. This kind of situation has been encountered several times in South Sulawesi. The direct result is difficulty in supplying water to the ponds especially on the part of shrimp farms which require more, as well as, better quality water.
The most direct solution to this problem is to widen and straighten such channels so that it becomes shorter. There are already many government projects to rehabilitate and improve such canals except that in some areas it is often difficult to implement because the farmers are not ready to sacrifice a small portion of their land for widening and straightening such canals. As long as this canal problem remains, it will be difficult to improve culture technology in such areas because water is a determining factor in shrimp culture.
There are still many tambaks with very small effective area relative to the gross area because they have not yet been excavated or leveled properly such that large portions within the ponds are not productive. There are also many tambaks with very large pond compartments ( 5–10 ha), so that water and pest management as well as pond preparation prior to stocking becomes very difficult. With smaller pond compartments, harvesting becomes less complicated while pest control and water management becomes easier to do.
In some areas, especially in the north coast of Java and the east coast of Central Lampung, the coastal slope is so gradual that a thick deposit of mud and silt has been formed due to siltation. Tambaks in such areas have difficulties in obtaining enough clean seawater. It is necessary in these areas to widen the green belt. The establishment of siltation ponds also helps but it is not a final solution to such a problem.
Many tambaks have very low pond bottom elevation so that the pond bottom cannot be properly dried. In shrimp culture, the drying of the pond bottom appears to be one requirement which has to be fulfilled. This problem is even more critical in areas with very narrow tidal ranges such as the east coast of Central and Southern Lampung, north coast of Central and West Java. In these areas, a pump is necessary to assist in drying the pond bottom.
Due to improper layout, along with a network of small dikes, as well as wooden gates without running boards for vehicles, most tambak areas are virtually inaccessible to four-wheel vehicles. With such situation, communication, mobility and transport of harvests becomes a serious problem in most traditional tambaks. As a result almost all activities can be done only with very low efficiency.
2.2 Culture Operations
Generally, most tambaks have very thick layers of silt and mud especially along the pond bottom canals such that during the entire culture period, the pond bottom poses danger to the shrimp stock due to high hydrogen sulfide and low oxygen concentrations. Most tambaks also, are too shallow so that during noontime the water temperature becomes too high. Maintenance (deepening of pond-bottom canals, drying period and routine disposal of fine silt during the culture period) combined with thorough drying of the pond bottom before each stocking can also reduce the aforementioned dangers.
The management of salinity during the growing period is very important to ensure the health and growth of the shrimps being cultured. In a traditional tambak, generally it is difficult to manage the salinity because the canal is inadequate and is almost never maintained. To reduce this problem, the improvement and rehabilitation of the canal system is absolutely necessary. In addition ground water (fresh or brackish) supply from a well can also help in solving this problem especially at the height of the dry season during which the salinity becomes too high as well as during the rainy season when the salinity becomes too low.
Pest eradication often cannot be done effectively because of various factors such as over-sized pond compartment, irregular pond shape, uneven pond bottom, inadequate pre-stocking preparation and deficiency in the screening of water supply. These factors together with slipshod acclimatization are primary reasons for high mortality.
The use of pesticides which are cumulative and persistent (e.g. Endrin, Thiodan, Brestan-60) to eradicate pond pest is often difficult to stop because generally farmers want only pesticides which are easy to use, effective and cheap. Such materials are very dangerous to the environment. Excessive use can adversely affect shrimp health directly by affecting their growth and eventually even endanger the consumer.
2.3 Supply of Pond Inputs
A steady supply of shrimp fry is an important factor in determining the success of shrimp farming. Because the stocking period of the traditional tambak still depends very much on the climatic season, the demand for shrimp fry increases sharply during the stocking period which normally is very short. During such period, shrimp fry supply becomes critical. Fry price can jump up to the range of Rp. 35-Rp. 40 per piece for natural fry and Rp. 25-Rp. 27 for hatchery fry. On the other hand, outside the stocking period there is an oversupply of fry and the selling price drops drastically (Rp. 7-Rp. 12 per piece). Such period is a critical time for hatcheries. This phenomenon can be reduced by modifying the stocking pattern which basically depends only on the ability to supply the ponds with water along with pre-stocking preparation. In other words, water supply appears to be the dominant factor in ascertaining when a pond is ready to stock.
Ensuring the smooth delivery of equipment and pond inputs (fry, fertilizer, feed, etc.) together with the transport of harvests to the market are, at the very least bothersome problems, but can also result in higher operational costs due to mobility problems in traditional tambak areas. The preservation of shrimp quality at harvest appears to be a critical factor which should be thoroughly solved because if the quality of shrimp coming from the tambak is no longer good, then it will be difficult for it to compete in the world market.
2.4 Working Capital
For small-scale shrimp farmers, working capital is a major constraint even if they use only traditional or extensive systems. Joint ventures between investors and small farmers are highly desirable. The investor may opt to manage the tambak directly while hiring the farmer as workers, or an investor may opt to let the farmer continue to manage the tambak with the investor providing all the required inputs on credit as well as technical guidance.
An example of such joint ventures which can be developed as a model is the arrangement between private companies (usually suppliers of pond inputs and/or operator of processing/cold storage plants and or intensive shrimp farms) and farmers which exist in East and Central Java. There the large companies provide the inputs such as fry and feeds on credit, as well as technical guidance. Almost all the shrimp farmers who availed of such arrangements succeeded to the mutual benefit of both parties.
In such arrangements goodwill and determination on the part of the investor company are expected by the farmers in addition to their commercial motives. On the other hand the companies also expect the cooperating farmers to be honest, persevering, and serious in their work.
3. INTENSIVE SHRIMP CULTURE
Although the type of activities are similar in intensive and extensive culture (i.e., culture species is tiger shrimps in both systems using earthen ponds with brackishwater as culture medium) the problems in intensive farms differs from those of traditional or extensive farms due to the following conditions:
In response to the above situation, special steps need to be applied in order to ensure a good growth rate and survival up to the end of the rearing period. Basically these steps involve the maintenance of good water quality which in turn depends to start with on the site selection, pond design and construction as well as to the management of the culture operations. Based on observations in some intensive shrimp farms in Indonesia, the following problems have been noted:
3.1 Site Selection and Design
Site selection in general is not based on technical considerations. There is a preference for areas which are cheaper and easily accessible. It is common to find a hatchery located in the middle of the pond area with the expectation that the shrimp fry can then be conveniently transferred to the ponds without requiring transportation and any special effort. However the water discharges from the ponds can be harmful to the shrimp larvae. In order to have water of a quality suitable for larval rearing, seawater has to be hauled from a distant place offshore by boat.
Many shrimp farmers merely follow one another. Usually, if a farmer becomes successful in a given area, the others will rush in without considering the supply and drainage of water. This kind of situation can be found in the Muncar area, East Java; Denpasar and Jembrana in Bali; Krawang, West Java; and Taboneo, South Kalimantan.
Because of such tendency, some areas are already so overcrowded with tambak that its natural carrying capacity has already been exceeded. In this situation, there is a need for assistance, extension, guidance and supervision from the local government. Obviously each location must be assessed on the basis of the carrying capacity especially in terms of seawater supply, discharge of pond effluents and the ecology of the surrounding area.
Obtaining good quality water and the discharge of waste water are especially serious in areas where the coastal slope is very gradual and have very thick siltymud bottom deposits due to heavy siltation from the rivers, on top of weak tidal currents. This situation can be found in the north coast of Java (Krawang, Serang, Tangerang, Cirebon) and the east coast of Lampung. In these areas not only is it difficult to obtain good quality seawater but the discharge of waste water from the ponds also adds to the siltation causing fine silt to be deposited along the coast. Under this condition it is certain that the condition of the shrimp pond will deteriorate rapidly. To overcome this problem, there is a need to develop a centralized water intake canal so that better quality water, coming further offshore, can be obtained for distribution to the shrimp farms. Each farm can continue to have its own drain canal but a siltation pond need to be provided.
One of the most common problem encountered is the failure to match the water supply available to the area of the pond to be developed and the type of culture system to be used. In constructing the shrimp farm, shrimp farmers who wish to follow the requirements for intensive pond culture should give importance to the following factors:
Weaknesses which are still apparent among others are:
3.2 Grow-out Operations
3.2.1 Acid-sulfate soil
In new ponds constructed on land with acid-sulfate soil it is advisable to correct the soil condition first using reclamation procedures before stocking. Such a process would take the equivalent of about one growing season. Usually this is not followed because the tambak operators do not want to lose time and therefore prefer to stock immediately. A good harvest might be obtained the first time, but during the next cycles many difficulties will be encountered because the pond bottom is likely to become more acidic. Because of failure to spare some time for conditioning or perhaps because of leaks and seepages, pond preparation prior to stocking is often inadequate. The result is a poor harvest. Disposal of wastes, drying of pond bottom, and pest eradication are absolutely necessary to attain a good harvest. This activity is even more important in ponds which is already productive and is being used repeatedly.
3.2.2 Water supply and carrying capacity
Generally newcomers in shrimp growing are too greedy for high production and would push the stocking density to high levels without considering the water supply and the carrying capacity of the area. Such practice increases the risk of failure because of the difficulty in maintaining environmental quality and the shrimps being cultured are always under a condition of stress. Poor environmental quality together with deteriorating physical condition of the shrimp leads to development of diseases such that the tambak operator is forced to harvest prematurely. It should be noted that the tonnage of shrimps obtained at harvest is not always proportional to the proceeds from sale because the size at harvest has an effect on the price.
3.2.3 Deep mud layer
Pond bottoms often have very thick mud deposits. This can be encountered in shrimp ponds which were established in former milkfish pond with low pond bottom elevation. In order to be successful it is absolutely necessary to change the condition of the pond so that the bottom becomes hard. Without such action, at most after two harvests, it will already be difficult to maintain the pond productivity. The dredging of the silty-mud layer need not be done all at once but should be done gradually and repeatedly after each harvest. Depending upon the thickness and the texture of the soil, it might be possible to attain a hard bottom after 3 to 4 harvests. During the drying process, it is necessary to turn over the pond soil that has already dried with a hoe. At the same time, dolomite can be applied to help speed up the hardening process. The occurence of leaks and seepages should be guarded against during the drying process.
3.2.4 Salinity fluctuations
Salinity fluctuation is one problem that is always encountered. Often the salinity level fluctuates within extreme ranges: very low during rainy season in ponds that are far from the sea, and on the other hand too high during the dry season especially in ponds located along the coastline which have no access to river mouths. Fluctuation in salinity can have a direct effect on the physiological processes of the shrimps causing stress. Aside from this it also has an effect on the stability of the plankton population which is needed to maintain a good pond environment.
One problem that is critical with regards salinity concerns the stocking schedule especially in a tambak which is located far from the coastline. During prolonged wet season it is often difficult to stock shrimp fry because the salinity is too low, thus the stocking is forced to be postponed again and again. This kind of situation disturbs and results in losses on the part of the tambak farmer although this really is just the result of poor site selection.
Under such a tight situation, it is often necessary to implement emergency measures which are counted upon to save the shrimp fry which are to be stocked. Emergency measures that can be applied area as follows:
- Acclimatization of the shrimp fry in the hatchery before these are transported to the tambak in order to lower the salinity up to a level which the tambak water is expected to attain.
For traditional tambak, the acclimatization box is replaced with small compartments with earthen dikes. Release of fry into the grow-out pond is done by opening up the small dikes. Generally mortality occurs during the stocking of fry because of deficient acclimatization.
3.2.5 Use of well water
The use of a bored well as a source of fresh or brackishwater in order to deal with the salinity problem in the tambak often experiences some complications because of poor water quality (high Fe2+, NH3, and H2S or low O2). Aside from this, digging too many wells within the tambak area can be dangerous as it can result in the lowering of the ground surface. It should be remembered that the volume of water required for tambak operation is quite high.
The maintenance of water quality using biological or other types of filter is very difficult to apply in a tambak situation because of the high water requirement. One method that has proved to be adequate is aeration (for precipitating Fe2+, and oxidizing H2s) and to hold the water inside a reservoir pond which already has plankton population before letting the water into the pond compartments. A large portion of NH4 (ammonium) is utilized by the plankton directly as a nitrogen source. The use of a paddlewheel inside the reservoir pond can hasten further the lowering of Fe2+, NH3, and H2S (Poernomo, 1988.)
3.2.6 Plankton scarcity and blooms
Plankton scarcity is a characteristic of tambak newly constructed in an area with pyrite soil or peaty soil. (Pyrite soil is more common.) During the initial stage of operation the pond water is always clear and not capable of growing plankton even by applying a large amount of fertilizer. This happens because the nutrients from the fertilizer, mainly P, is immediately bound to the iron (FE) and aluminum (A1) and is no longer available to the plankton for propagation. This problem can easily be solved using reclamation procedures on the pond bottom which involves drying, leaching and disposal of the Fe and A1 from inside the tambak. After reclamation one ton of lime is spread on the pond bottom and preparation made for stocking. Fertilization with TSP and Urea is necessary to stimulate plankton growth.
On the other hand, plankton bloom is a special characteristic of a tambak which have already been repeatedly stocked and harvested from. The primary reasons for the rapid propagation and eventual blooming of the plankton are:
The signs of plankton blooms among others are as follows:
The effects of the said condition are:
Solutions to the above problems are:
3.2.7 Epiphytic organisms
In shrimp ponds with poor condition, shrimp with algal growth can often be encountered. In extreme cases, the whole body and the gills are full of epiphytic organisms until the survival is affected. The primary reasons for such occurence are:
The result of such condition are:
Corrective measures to be instituted are:
3.2.8 Tail-rot and broken appendages
Tail-rot and broken legs and antennae in shrimps are usually encountered in ponds with very high stocking density, which are not too careful in cleaning accumulated wastes on the pond bottom thus encouraging the development of chitineous bacteria in the rich pond bottom. Physical injuries on various parts of the body (tail, antennules and antennae) becomes infected by the said bacteria until it starts to rot and break. As a result of such situation, the shrimp does not eat as much and in severe cases high mortality occurs. Because the shrimp no longer appears whole its market price goes down.
If the condition is not yet too severe, the situation can still be corrected by cleaning up the accumulated wastes continuously, improving and maintaining the water quality, and by applying organic copper sulfate (granular) at 1 mg/l, or Bromocept at 0.1–0.3 mg/l. Routine activity afterwards include thorough pond preparation after each harvest. Stocking density should be adjusted according to the carrying capacity of the environment.
3.2.9 Extraneous organisms
Organisms interfering with the culture which are commonly encountered are jembret or Mysid shrimps (Mesodoposis sp.) and wild shrimps such as M. monoceros, P. merguiensis and M. brevicornis. The mysid population is often dense especially in fertile ponds after the culture has entered its third or fourth month. Many wild shrimps occur in ponds which are near the coastline which are rich with wild shrimp fry (Pirzan and Poernomo, 1985.)
Even if the live mysids are eaten directly by the shrimps, its nutritional contribution is very insignificant. A dense population can interfere with the cultured shrimps because they can become strong competitors in the use of oxygen aside from the wastes they excrete which can lead to the deterioration of the environment. Often the population of wild shrimps and mysids might even be denser than that of the tiger shrimps being cultured. The result of such interference is that the cultured shrimps are always in a condition of stress and the effect is evident in the growth rate.
The eradication of such pests using chemicals is very difficult because the said organisms have almost the same tolerances and biological requirements as the shrimps being cultured. Because mysids and wild shrimps represent high-quality fresh natural food for the tiger shrimps, it is strongly suggested that these extraneous organisms be collected, the mysids using finemesh screens and the wild shrimps using liftnets and cast nets. The mysids and wild shrimps that have already been gathered and are no longer alive can be given directly as fresh natural feed to the tiger shrimps being cultured as a supplement to the pelletized feed and at the same time also compliment with the pellets in terms of making the nutrients available to the shrimps more complete.
3.2.10 Uneven growth
Lately the uneven growth or non-uniform sizes seems to be occuring more often along with retarded growth. This problem is causing great anxiety especially among intensive shrimp growers because previously this has never happened.
There are many factors which contribute to this problem. Retarded growth is encountered often in new ponds built in a pyrite soil area which has not yet been reclaimed. Cases of slow growth have also been reported in ponds with normal soil but uses water from a source which has a high concentration of iron (Fe2+). In this connection care should be taken in using a reservoir pond along the coastline which has groundwater with a high hardness level. It is necessary to test and check the quality of the water because water quality can be ascertained only after continuous pumping. It happens that the reason for the stunting of the shrimps is poor quality because of high iron (Fe2+) concentration. Solution to this problem is to be reclaim the pond bottom soil and to use aeration.
Other factors which cause uneven growth among the shrimps are:
3.2.11 Blue shrimps
Lately there has been several cases of blue shrimps in intensive ponds. Although there is no problem in the growth, blue shrimps command a lower price in the market because supposedly such color in shrimps is not liked by the Japanese buyers. (Blue shrimps once boiled has a paler color and is not as brilliant as normal shrimps.) The color of normal shrimps comes from, among others, asthaxanthin as precursor to asthaxanthin. The shrimp can use up almost all of the carotenoids as its pigment source. Failure in the formation of the pigment has been cited as one of the factors causing such developement, either alone or in combination with others. Feed with a nutritional composition which is deficient in pigments clearly will result in the production of blue shrimps. This writer has once tried a feed pellet from Taiwan on two groups of tiger shrimps with a result which is sufficiently convincing. One group which was fed the said pellets only all became blue after almost one month of rearing. The second group which was fed pellets with supplemental food (shells and trash fish) all had normal coloration and turned a brilliant red upon boiling.
Often, even if the nutritional content of the feed given is good, shrimps which are always under stress because of an environment which is frequently poor can also become blue. This is probably due to an abnormal metabolic process because the activity of the enzymes that are supposed to break down the carotenoids and other similar substances as precursor to asthaxanthin are disturbed.
The above explanation indicates that feed quality and environmental factors have a large share in the emergence of blue shrimps. Because of this, corrective action should be taken primarily as follows:
3.2.12 Soft-shell shrimps
Sudden molting when the shrimps are about to be harvested often happens. This can hit the pond operator very badly because the price of the shrimps will drop.
Molting process is a normal occurrence in shrimps because without molting the shrimps cannot grow. But the occurence of molting can also happen in an abnormal manner if the shrimps feel a sudden stimulus such that it causes stress (e.g., change in temperature, salinity and other factors.) Shrimps are very sensitive to changes in environmental factors (drastic changes in temperature, salinity and other chenical factors.) Such changes can spur the emergences of stress and can proceed to stimulate the process of ecdysis or molting abruptly.
Because of this it is necessary to conduct the harvest rapidly. This can be done if the pond construction has been well thought of.
Pirzan, A.M. dan A. Poernomo. 1985 Biological and ecological aspects of the jambret (Mesopodopsis sp.) as pests in tambaks in South Sulawesi and ways of controlling them (in Indonesian). J. Pen. Budidaya Pantai, Maros (I), pp. 27–28.
Poernomo, A.1986 Technology package for reclamation of tambak with acid sulfate condition (in Indonesian). J. Pen. Litbang Pertanian V (4), pp. 100–103.
Poernomo, A. 1988 Dominant environmental factor in intensive shrimp culture (in Indonesian). Seminar Budidaya Udang Intensif, Jakarta, April 1988, p.65.
Fishery Product Quality Testing and Guidance Centre, Jakarta
Shrimp quality, especially that of pond shrimps, is affected by the rearing environment, harvest method and postharvest handling. Commercially, three quality standards are known, namely: 1) labelling standard, 2) freshness, that is whether it is fit for human consumption, and 3) health standard which sets the allowable concentration of hazardous contaminants in the form of foreign matter, chemicals for microorganisms.
One problem in shrimp quality that is encountered in the marketing of shrimps abroad is the existence of a block list criteria by the US-FDA. Indonesian shrimp can be cleared for release from the customs zone of the warehouse only after a permit from the US-FDA. As a result the shrimp price in the US is depressed because importers already include storage fees and speculation on the price if the shrimp has to be reprocessed because the observed quality is not good enough. Aside from this the existence of the US-FDA block list affects the reputation of Indonesian shrimps in the world market in general. In order to solve the existing problems all parties concerned in the shrimp industry need to always act together in order for the product to comply with the requirements demanded by the market.
Indonesian shrimp production has been on the increase during PELITA IV. During PELITA V, shrimp production, primarily from tambak has been projected to increase every year. This is because of the awareness that the world shrimp demand is still large, and that in order to fill such demand, Indonesia has the capability to increase shrimp production primarily through aquaculture and also through capture.
It is evident that Indonesian shrimp production increased along with the increase of world shrimp production especially from other developing countries in Asia and Latin America. On the other hand the shrimp market regions are in the developed countries such as Japan, Europe and North America.
With the increasing possibility of rising world shrimp production a stiffer competition in the world shrimp market is likely to happen. Such competition will primarily hinge on two factors, that is, price and quality. In order to compete in price, whether we like it or not, production efficiency or production cost reduction should be aimed both in the tambak as well as in the processing plants. At the same time, competition in quality will continue and technically will proceed with improvement in technology specially for processing and packing, analytical methods along with health/sanitation requirements which is very much affected by the standard of living.
Because the greater part of Indonesian shrimp production is projected for export as a means of generating foreign exchange, it is better, if not necessary, to follow world shrimp production trends and work to increase its quality so that we can make available shrimps with quality which is in accordance with world market demands.
Some factors which affect shrimp quality are environmental (preharvest), harvest method, postharvest handling both during transportation and distribution as well as processing and storage in the cold storage plant.
2. SHRIMP QUALITY STANDARDS
In world trade, three quality standards are known; these are, labeling requirement standard, freshness standard and health quality standard. The three quality standards, in some countries, are established and applied separately, but in Indonesia are still treated as one, and is known as the frozen shrimp quality standard as approved by the Minister of Agriculture and adopted by the Department of Commerce.
2.1 Labelling Standard
The standard for labeling is intended for producers to declare the specification of their product as packed so that the consumer will not be cheated materially.
According to the regulation the label should state the correct weight, the common or usual name of the product (i.e. the type of shrimp) as well as other relevant information such as the processing method.
In Indonesia the standard regarding what should be included in the label of the food/drink product is regulated by the Minister of Health, more specifically the Directorate General for Food and Drug Supervision. The said regulations are laid down so that the government can administratively supervise the contents that can be found in a food product and protect to the consumers. This matter also applies to some fishery products that are packaged such as frozen shrimp.
2.2 Freshness Standard
The freshness quality standard regulates the degree of freshness of a product that is fit for human consumption. There is a possibility that a product does not meet the freshness quality standard but does not cause visible ill-effect on the health.
Shrimp freshness is ascertained through its appearance, consistency and odor. Generally shrimps which have already deteriorated in quality will no longer look clear. Aside from this, black spots are also visible in the abdominal segments. The presence of black spots is due to oxidation, primarily enzymatic, that changes the amino acid tyrosin in the shrimp flesh into a polymer known as melamin which is dark brown in colour. Because the oxidation is extensive, it becomes visible in the abdominal segments.
Shrimp which is no longer fresh can also be detected through the consistency of its flesh which losses its firmness because the tissues which consist of protein has already decomposed. The most conspicuous parameter is the odor. Shrimp which has decomposed smells rotten. This is due to the generation of chemicals of decomposition such as organic sulfides, ammonia and similar substances, primarily indole which has a very unpleasant smell. The process of indole formation takes place because of the activity of microorganisms which are able to convert the amino acid triptophan into indole.
The concentration of indole in shrimps considered by the US-FDA as having the lowest quality is 50μ g% and above (Class 3); at 25 – 50 μ g% (Class 2), the shrimp quality is considered tolerable, and those considered fresh has an indol concentration of less than 25 μ g% (Class 1). As a whole, shrimps which are acceptable to foreign consumers, specifically the US-FDA are:
In Indonesia sampling still uses the AQL 6.5 method while in the USA, a minimum of 6 and a maximum of 8 samples are taken for testing for freshness, with the minimum depending upon the number of packages in one batch (for fresh frozen shrimps), while for frozen cooked shrimp, a minimum of 12 and a maximum of 18 samples are taken depending on the number of packages in one batch.
Freshness is tested using organoleptic methods conducted by experienced persons, and in doubtful situation confirmed by chemical analysis of indole content using the AOAC method. The method basically involves distillation of the indole after alcohol extraction, where the indole in the distillate is extracted again using organic solvents (chloroform) and made to react with Pdimethyl benzaldehyde which ends up with a red color and is measured using a spectrophotometer at λ 560 nm.
2.3 Health Standard
This standard sets a limit to the presence of dangerous contaminants in the form of substances which can contain dangerous substances. Such contaminants can consist of chemicals, foreign matter or microbes.
2.3.1 Chemical contaminants
Generally chemical contaminants in shrimps consist of contamination or residues of insecticides/pesticides, antibiotics and heavy metals.
Insecticide and pesticide residues which are stipulated by some countries consist of Dieldrin, benzene hexachloride (BHC), Chlordone, Chlordecon, DDT, DDE, TDE, Endrine, Heptachlor, Heptachlor epoxide and Mirex.
Antibiotics which are usually closely watched are penicillin, chloramphenicol, tetracycline, etc. while heavy metal residues which are generally stipulated consist primarily of mercury and other metals such as lead, cadmium and arsenic. Aside from these, residual contamination may also consist of other chemicals whether normally dangerous or not such as cyanide, lubricating oil, sulfites and others.
Pesticides normally are analyzed by using GLC, antibiotics can be analyzed by HPLC and heavy metals with AAS. Chemical residues normally originate from the water (environmental), but this does not eliminate the possibility of contamination during transport, distribution, processing or storage.
2.3.2 Foreign matter
Foreign matter in shrimps consists of such things as sand/stone, nails, insect fragments, jewelry and others. Such contamination can occur from the production unit up to the processing unit. Contamination by such foreign matter usually does not pose any hazard, but has the possibility of bringing hazardous substances or is a reflection of unsanitary handling.
Contaminations with insect fragments such as parts of flies, ants, cockroaches and others is a usual problem in tropical areas. For this, some countries, especially America, always look for possible contamination with insect fragments and filth including human hair. Analytical method used is flotation method or sieved method (AOAC).
2.3.3 Microbial contamination
Limits for microbial contaminants is primarily directed to a few pathogenic species such as Salmonela, Vibrio and others. But other microbial species such as intestinal microbes also serve as indicator that a certain product has been subjected to faecal contamination which makes it unfit for human consumption or may bring phatogenic microbes.
Some countries have varying requirements depending upon the frequency of spread of infections disease in the concerned (exporting) country. But the requirements which generally are fixed are total bacterial counts, presence/absence of Coliform, E. coli, Vibrio cholerae or Parahaemolyticus, Salmonella, Shigella, Staphylococcus and for food products that are ready to eat, Leisteria monositogenes. For microbial pathogens, the requirement normally is for these to be negative using analytical method which the importing country normally uses, e.g., for the USA the US-FDA uses BAM (Bacteriological Analytical Manual), which is published by the FDA itself and is periodically revised.
Microbial contamination normally occurs while the shrimp is still being reared (environment), during harvest, or after harvest (during transport, distribution, processing or storage). Microbial carriers can include the containers used, washing water, pond water, domestic animals, insects (flies, cockroaches, etc), other animals such as rats, or even human hands and clothing and furthermore can include the packaging material or the atmosphere.
3. PROBLEMS AND SOLUTIONS
One problem that is encountered in the export of Indonesian shrimp is the presence of a block list criteria on the part of the US-FDA. With the said block list criteria, Indonesian shrimps entering the US are always detained - that is held in storage in the customs zone. Such shrimps are released only if the US-FDA has given its permit after the shrimps have passed through inspection. The result of such detention is a higher storage fee and speculation fee that is fairly high in case such shrimps have to be reprocessed because the quality does not meet FDA standards. Because of this, American buyers usually include such factors in their computation and will ask for a lower price for Indonesian shrimps. This is not felt directly by the Indonesian exporter, although in reality the price obtained by the exporter is already lower by the amount though necessary to compensate for longer storage period and possible reprocessing. It is estimated that the magnitude of such speculative price reduction is as much as 30 per cent of the total value of the shrimps.
In addition the existence of the US-FDA block list criteria affects the reputation of Indonesian shrimps in the foreign market. The reason given for the inclusion of Indonesian shrimps in the block list is that the quality of some Indonesian shrimps still do not meet the standards set by the US-FDA, that is the presence of decomposed shrimps, the presence of Salmonella along with filth, while in the Japanese market, what pre-occupies the Japanese health authorities is the presence of Vibrio parahaemoliticus and Salmonella. The difference in the said requirements between Japan and USA is due to the fact that in the US Vibrio parahaemoliticus infection is still often encountered.
With the above-mentioned facts, the fundamental problems now are freshness and contamination by microbes and filth. The presence of decomposed shrimps has been blamed primarily on the microbio logical activity that is capable of forming indole from the amino acid tryptophan. In nature some microbial species can always be encountered on the surface (mucus) and stomach content of shrimps, these are: Achromobacterium, Bacillus, Micrococcus, Pseudomonas, Flavobacterium, Alcaligenes and Proteus.
The reason for the decomposition of shrimps in tropical areas is the occurence of mesophylic bacteria that are often encountered in nature as mentioned above. The degree of activity of the said bacteria varies depending upon the existing condition, primarily temperature. In iced shrimps, usually decomposition is due to Acromobacter and often Pseudomonas but if the temperature is relatively high, Proteus is more dominant (Frazier, 1967). Survey results at the BBPMHP show that indole concentration in white shrimps kept at room temperature for 20 hours increases by about 650 per cent. In contrast when kept in ice, the indole concentration increases only by 71 per cent, during the same time period (Suparjo, 1988). Based on an on-going study at BBPMHP the results for tiger shrimps are not too different and preliminary results point to the fact that shrimps which are not iced until 10 hours after, drops to Class 3 category based on US-FDA standards (indole concentration 50 μ g%). Because of this, in order to preserve freshness, the use of sufficient ice in order to bring down the temperature of the shrimp to 0°C is absolutely necessary during handling from distribution up to processing.
The speed of decomposition is also affected greatly by the initial microbial count, where the larger the counts, the faster would the decomposition be. Because of this, lowering the initial microbial count is very important. As an example, study results at BBPMHP indicate that through washing of fish is capable of lowering the microbial count by half. Shrimps decompose faster when compared with fish. This is understandable, because shrimps has a higher free amino acid content at about 5% of the flesh, which are easily exploited by microorganisms in decomposition activity (free amino acid in fish flesh is only about 1 to 2%).
Physical contamination and filth (insect fragments, hair, etc.) can happen starting from harvest up to processing in the cold storage. This is easy to understand because Indonesian as a tropical country has many species, as well as a big population of insects. When viewed from the chain of handlier from tambak up to export, the biggest possibility of filth contamination occurs in the tambak, during collection and during transportation because during these steps are handled in the open. Because in the cold storage the said shrimps are sorted and washed, it is expected that filth contamination from outside the processing plant can be removed. However due to a large volume of shrimps, and perhaps a high degree of contamination with filth in the form of very small fragments, for example fly and ant appendages, the removal of such contamination in the cold storage plant is not easy. For this reason prevention of contamination is the best thing to do. For this, the use of clean and closed containers will already be of much help. The handling of shrimps directly on the ground or on the floor also makes it easier to be contaminated. Also because shrimps have an attractive odor, to some types of insects and animals, handling shrimps in open containers also adds to the possibility of contamination.
To prevent and reduce filth contamination in shrimps, in some cold storage plants it is necessary to exert some effort, that is in the proper sorting and washing of shrimps. In addition this should be done by properly-garbed workers (head caps, no hand/finger ornaments including nail polish, short fingernails).
Microbial contamination is a more complex problem. This is because in nature shrimps live in water. In such environment, shrimps are already contaminated by microbes. Because of this, what is necessary, is to prevent contamination with pathogenic/intestinal microbes, reduce the initial microbial count; along with slowing down of microbial activity so that such microbes will not cause rapid decomposition and the phatogenes will not rapidly reproduce.
Some species of microorganisms can live only in water with certain salinity levels and generally such microorganism are halophylic species. Aside from this some species of microorganisms are tolerant to salt and can live with or without salt. Such microorganism include Halobacterium, Saricina, Micrococcus, Pseudomonas, Vibrio, Prediococcus and Achromobacter. Some of the species classified under the above mentioned genera, including Vibrio are pathogenic and others are decomposing microorganisms. Although some of species belonging to the above-mentioned genera may not be pathogenic, still their number will still affect the quality of the shrimps, when the total bacterial count normally required should not be more than 5×105 per gram.
The Vibrio problem requires special attention because Vibrio cholera and Parachaemolyticus cannot be positively confirmed in shrimps that are exported. Because of this, prevention of contamination by such microorganisms from the tambak (rearing area) to the cold storage, is necessary. Serious attention should be given by tambak and cold storage operators if an epidemic of vomiting/diarrhea is on the spread, caused probably by Vibrio. This can contaminate surrounding waters and can be carried by tambak workers, shrimp collectors, cold storage workers, or by insects and other animals, and will increase the possibility of contamination.
Other microorganisms which require attention are those belonging to the Enterobacteriaceae family, because this family of microbes are part of the intestinal microorganisms i.e., E. coli, Salmonella and Shigella which are strictly regulated by some countries, specially western countries and primarily the United States. Although these microbes are not tolerant to salt, the possibility of survival in the tambak for a certain period of time still exist. As an example, based on the preliminary results of simulation tests at BBPMHP, Salmonella can survive in a brackishwater pond for a definite time period, that is its population increases and reaches its maximum on the 4th to 5th day and afterwards decreases, but they can still be encountered on the 10th day. Studies are still being conducted on the water, mud and shrimps and will support the preliminary data which is still in the form of a question as to whether Salmonella can survive in a tambak, because studies in some laboratories in Asia still show conflicting data. The said simulation experiments are accompanied by field tests and results so far in the Karawang area has been negative. The said experiments are still being continued and will be expanded to include more species of microorganisms.
Contamination by chemical residues is a problem arising from the increased and frequent use of chemical pesticides, fertilizers and other inputs for increasing agricultural production. Aside from this, the increasing level of industrial pollution and wastes and other human activities demand our close attention in order to maintain the quality of cultured shrimps. One way or another, one sign that chemical residues is starting to be feared is the existence of special requests or requirements, for example the special monitoring on the presence of chemical residues from shrimp importing countries. There are many possible chemical substances that can contaminate or cause the presence of residues, such as insecticides, atibiotics and heavy metals. Along this line, shrimp quality monitoring with regards to chemical residues is necessary.
Although results of some BBPMHP surveys on pond shrimps in the Karawang area regarding insecticide and heavy metal residues indicate that the concentration is still far from the standard treshold levels, it appears that we are obliged to diligently carry out the said survey and immediately find a way to solve it if the level of residue or contamination starts to increase. Mercury concentration of shrimps raised in the Karawang area hovers around 0.05 ppm which is higher in comparison to the concentration in water at 0.05 ppb, but slightly lower than that of its mud sample (0.06 ppm). Meanwhile the insecticide that has been detected in the shrimps from the same area is lindane at 3.27 ppb and MIPC at 39.62 ppb.
In the coming years, competition for shrimp quality in the world is going to become more intense. At the same time with the rise of the standard of living and higher levels of technology and science primarily in the area of analysis and health biochemistry, shrimp producers should start to think about the possibility of contamination whether it be physical, microbiological or chemical. Along this line, we should not close the possibility of intentional contamination for economic or political purposes. Because of this whoever feels responsible or feels like playing a role in increasing production as well as export of shrimps as a prime export commodity, should work together or in cooperation with each other and not separately from each other, in order to always strive to comply with the requirements of foreign consumers.
Survey methods and development of shrimp quality from rearing up to export should be conceptuallized. The establishment of Hazard Analysis of Critical Control Point or HACCP should be pursued. The use of this method at present is expanding in the field of quality control in the world. Because conditions change from one area to another, it is necessary to establish the critical point for each set of conditions and as a routine. The result of the Control Point Analysis of each tambak area, collection point or cold storage as determined by some laboratories, can then be discussed routinely in order to formulate ways of over coming them.
Quality maintenance from the tambak (postharvest), transportation, distribution and processing should be done using the concept of Good Manufacturing Practice (GMP). This will be effective only if done by the producers/processors themselves. The government can merely act as stimulator, guide and usually as supervisor. In order to apply the concept of GMP efficiently, all workers directly connected to the handling and processing of shrimps up to the managers should act as Quality controller.
4. CONCLUSIONS AND RECOMMENDATIONS
From the foregoing analysis it can be concluded that all parties involved in the shrimp industry should always work towards making their product comply with the quality requirements demanded by the market.
In order to grasp the problem of physical and chemical contaminations, physico-chemical surveys of the environment and other aspects should be attended to seriously.
The problem of microbial contamination is a complex one. Because of this, deeper knowledge of the microbiology of the environment primarily that of shrimp, is necessary through surveys, experiments and research. Such knowledge will possibly be very useful in providing inputs regarding the management of aquatic and marine environment like the results from the discussions during the Indo-Pacific Fishery Commission Working Party on Fish Technology and Marketing in Bangkok, 19 – 22 April 1988.
In order to help solve the above mentioned problems, some follow-up actions are recommended, these are as follows:
Harvey, Istr. and Zweigh (editor) 1980. Pesticide analytical methodology. American Society, Washington.
Food and Drug Administration. 1984 Bacteriological analytical manual 6th edition. FDA, Washington.
William (editor), 1984 Official methods of analysis of the Association of Official Analytical Chemists. AOAC, Virginia.
Food and Drug Administration. 1986 Current good manufacturing practice in manufacturing packaging or holding human food. FDA, Washington.
FAO. 1988 Report of the seventh session of the Indo-Pacific Fishery Commission on the Working Party on Fish Technology and Marketing. FAO, Rome.
Food and Drug Administration. 1988 Action level for poisonous or deleterious substances in human food and animal feed. FDA, Washington.
Dodd, C.1988 Plasma profilling a new method of detection of critical control points. In Food science and technology today. IFST, London.
Frazier, W.C.1967 Food microbiology, second edition. Tata Mc Graw Hill Publishing Company LTD, New Delhi.
Griffin, M.F. and Thomas, B.1979 The safe use of chemicals in agriculture. In Chemistry and agriculture. The Chemical Society, Burlington House, London.
Jaction, G.J. 1988 Public Health and research perspective on the microbial contamination of foods. Presented at the Symposium Food Safety and Perspectives. Rutgers Univ., New Brunswick.
Sumpeno Putro et al. 1988 Studies on microbiology of farmed shrimp. Report of the Seventh Session of the Indo-Pacific Fishery Commission on the Working Party and Fish Technology and Marketing. FAO, Rome.
Sunarya et al. 1988 Report on prawn hygiene projet. BBPMHP, Jakarta.
Suparjo. 1988 Effect of temperature and storage time on indole concentration in white shrimps (in Indonesian). Karya Utama Sarjana Kimia, Jurusan Kimia, MIPA,UI.
Thorpe, R. and Leaper, S.1988 Setting up and monitoring HACCP. In Food and science and technology today. IFST, London.
Waites, W.1988 Hazardous microorganisms and the hazard analysis control point system. In Food science and technology today. IFST, London.
Nucleus Shrimp Farm Estate Pilot Project, Karawang, West Java
The fall of shrimp prices has resulted in a slowdown in the operation of existing tambak and in the planning and development of new tambak projects. In order to overcome this setback, it is necessary to determine: 1. the possibility of using non-intensive culture technology in order to lower production cost since the feed requirement can be lowered by lowering the fry density; and 2. continue to apply intensive culture technology but with the use of locally made feed so as to lower production costs.
If the local feed has a quality at least as good as the imported feed, the second alternative, that is to lower production cost by using local feed will provide an opportunity for the local feed industry to seize the Indonesian shrimp feed market. This can happen if the local feedmillers can lower their production cost by using high quality and relatively cheaper local raw materials. Another method which should be attempted is for the feedmillers to band together and import the raw materials as one group.
The availability of local feeds with satisfactory quality and a relatively lower price, is expected to provide the necessary “push” for the shrimp growers to continue their production activities as well as their development programme.
Shrimp is a fisheries commodity which is very important in the fisheries trade, and has a fairly conspicuous contribution to the national income from nonoil export. This is because shrimps always have a fairly high price in both the local and international markets, and is not affected very much by world economic development which has not been very favorable during the last few years.
In 1976 world shrimp imports reached 332,000 tons with a value of around US$ 1.45 billion. In 1985 the volume has risen to 557,000 tons (around 67.8% increase) with a value that has risen to US$ 3.18 billion (around 119.3% increase). When compared with the total shrimp production of 1985, the import volume constitutes only 28.7 per cent.
A large part of Indonesian shrimp production is exported, primarily to Japan. The volume exported to Japan is 80% of the entire Indonesian shrimp export.
As the biggest shrimp importing country, one factor that affects the volume of demand is the high level of income-elasticity of demand for shrimps in Japan compared with that of other shrimp consuming countries including the United States. Shrimp exporters to Japan consist of first India, next Indonesia, then China and Taiwan. The volume of Japanese shrimp imports from the said sources constitute 58.7 per cent of its total shrimp import in 1987.
The development during the said period has already stimulated entrepreneurs/investors in investing their capital in the shrimp fisheries sector both for production and for trading. This can be seen in the increase in the number of shrimp tambak ventures lately.
2. Shrimp Tambak Development in Indonesia up to 1988
During the first 4 years of PELITA IV, shrimp culture development shows positive results. This can be seen from the expansion of tambak area at an average rate of 3.4% per year from 225,197 ha in 1984 to 249,000 ha in 1987. During the same period, cultured shrimp production increased from 32,093 tons in 1984 to 53,240 tons in 1987 or an average increase of 18.6% per year.
2.1 Grow-Out Sector
The total number of companies which planned to invest in shrimp tambak up to 1988 reached 233 with a planned area of 25,983 ha. However up to this time only 3,886 ha or 15% of the planned development has been realized. The low realization is due to the following reasons, among others:
Meanwhile, the INTAM Kredit programme which is being implemented by the government to encourage this sector, apparently has a very low realization. This is because generally the farmers do not have securities available in the form of land certificates which is one of the bank requirements. On the other hand, INTAM Swadana (self-finance INTAM) apparently has a fairly high realization, even if the technology applied is not yet fully intensive so that the productivity is relatively low. The INTAM Kredit realization is only 566 ha while that for INTAM Swadana is 33,418 ha.
The total number of hatcheries that has been built by the private sector up to the present has reached 92 units with a total production capacity of 2.6 billion shrimp fry per year; if the government-operated hatcheries are included, the number reaches 107 units with a total production capacity of 2.9 billion shrimp fry per year.
At present the usage of locally produced shrimp feed is still very low when compared to the usage of imported feeds. Even, then, looking at the prospect of shrimp tambak development, during this time with government encouragement, there are already many applications for permit to develop new shrimp feedmills or for expansion (diversification) into shrimp feed by animal feed manufacturers. There are 7 feedmills that are already producing and marketing shrimp feed with a total production capacity which is still low when compared to the potential.
The low production primarily is due to the difficulty in marketing the product, mainly in the face of imported shrimp feeds which are relatively better in quality, as well as the fact that the said feeds are already known to the shrimp growers in Indonesia ever since the rise of shrimp culture ventures.
3. PRESENT CLIMATE FOR SHRIMP CULTURE VENTURES
3.1 Grow-out sector
Up to the last part of 1988 (September), shrimp prices can be said to be still stable in the world market. However, with the emergence of many shrimp producers like Taiwan, Thailand, Philippines and China, the supply of shrimps in Japan is becoming larger and larger. This is accompanied by the accumulation of frozen shrimp stocks in Japanese cold storage. As a result, the price in the Japanese market dropped drastically since September 1988.
If in the beginning the shrimp market in Indonesia can be considered a “seller's market” where the shrimp producers stipulate the condition for the sales transaction, this time the market characteristics have changed into a “buyer's market” where it is the buyers who lay down the stipulation. In this connection, the price of shrimp (size 30 pcs/kg) which before can reach Rp. 16,000 per kg, has already dropped to as low as Rp. 8,000 per kg during the same period in 1989.
As a result of the above situation, a weakening of the shrimp tambak sector has occured both in existing ponds and in the implementation of new tambak development plans. Of several tambak operators who have left their ponds fallow, most primarily applied intensive technology. On the other hand, tambaks using semi-intensive and traditional methods can still survive in the face of depressed shrimp prices in the market because their operational costs are very much lower.
3.2 Shrimp Feedmill Sector
In order to fill the shrimp feed requirements, at present, two sources of feed supply are found. The first source are local shrimp feed factories or livestock feed factories which have already diversified their operation, while the second source consists of imported feeds, the bulk of which comes from Taiwan.
3.2.1 Feed supply from local feedmills
From available data, the total capacity installed in the feedmills in Indonesia is 68,475 tons per year. Even then, based on information from the Directorate General of Fisheries, out of 23 feedmills registered only 7 feedmills are found operational in 1988. Out of those not yet in operation, some are still in the development stage while the rest are still in the planning stage only.
To estimate the feed supply in the local market, it is assumed that the existing feedmills are already fully operational with a production of about 60% of the existing capacity. The said figure is based on oral information from the Department of Industry which stated that generally Indonesian feedmills operate only at 60 % of their installed capacity. With that, total production (supply to local market) per year is estimated at 41,085 tons.
3.2.2 Imported feed supply
There are 10 companies registered as shrimp feed importers in Jakarta, which brought in several brands of feed from Taiwan. According to information coming from some importers, the average import volume per month per each company is 25 containers at 18 tons per container. There is also an estimate that the total shrimp feed import is 54,000 ton per year.
3.3 New Development in 1989
Prominent shrimp exporters to Japan consist of India, Indonesia, China, Thailand and Taiwan. In 1986/1987 with their ability to adopt shrimp culture technology and their success in production, Taiwan made a break-through by surpassing shrimp exports from India and Indonesia, and has consecutively held the position as the top shrimp exporter to Japan since then.
In anticipation of the development of new shrimp culture ventures which are almost totally intensive, new shrimp feedmills have already been established and numbers in the hundreds primarily to fill local demand but also for export. Apparently shrimp production from Taiwan cannot be maintained for a long period and is starting to experience failures in 1988. The failures that have occured are the result of deterioration of pond conditions and the emergence of diseases which is assumed to be due to too intensive operations in excess of the carrying capacity of the environment. With such development, the shrimp pond operators in Taiwan have started to lower their stocking density in the next period, and as a result the demand for shrimp feed dropped drastically.
The said drop in shrimp feed demand (or over capacity of feedmills) since 1988 already has negative consequences to the Taiwanese shrimp feedmillers because of their inability to fulfill their sales target. In order to overcome this problem many Taiwanese feedmill operators have already started to transfer to, or develop new feedmills in, other countries with large potentials for tambak development such as Thailand and Indonesia.
4. PROJECTIONS ON SHRIMP FEED DEMAND IN INDONESIA
In order to project the shrimp feed requirement, first, it is necessary to have data or estimates on the potential areas for tambak development in Indonesia; production estimates from the said areas according to the level of technology applied in each area.
4.1 Potential Area for Tambak Development
Based on data from the Directorate General of Fisheries in 1986, the tambak area in Indonesia was 241,400 ha. The provinces where the tambak can be found are Aceh (35,400 ha), West Java (46,700 ha), Central Java (26,600 ha), East Java (50,300 ha) and South Sulawesi (67,500 ha). The said areas have the highest tambak areas because tambak culture in the said areas has been practiced since the very beginning.
Again, according to the Directorate General of Fisheries, about 840,000 ha in Indonesia are potential areas for tambak development (extensification). There are also regions with fairly large development potentials, these are Riau (54,000 ha), South Sumatra (38,000 ha), East Kalimantan (52,000 ha), Maluku (20,000 ha) and Irian Jaya (580,000 ha).
On the other hand, even if the regions like Java, Aceh and other similar areas already have limited areas for extensification, the possibility of growth through intensification cannot be closed.
4.2 Growth in Shrimp Tambak Areas
According to the Directorate General of Fisheries, based on calculations during the 1984 – 1987 period, the tambak areas in Indonesia developed at a rate of 3.4 per cent per year. Even so, in a study made by the Asian Development Bank (Indonesian Fisheries Economic Study), it is estimated that intensive and semi-intensive shrimp culture area is growing at the rate of 10 per cent. In addition, the rate of growth of traditional tambak area can be estimated from the remaining areas with existing potential for development.
In this paper, the growth of tambak area development is estimated with a lower rate assumed (around 2% per year total). With this rate of development, the 241,400 ha in 1986 is estimated to reach 309,700 ha by 1996.
For intensive and semi-intensive tambak development, the assumption used (in this paper) is based on the estimate given by the ADB, that is 10 per cent per year. At this rate the area of intensive tambak is estimated to increase from 1,200 ha in 1986 to 2,800 ha in 1996. Meanwhile the area of semi-intensive tambak will rise from 18,100 ha in 1986 to 32,400 ha in 1996.
4.3 Projection on Tambak Shrimp Production
Projection on shrimp production can be made based upon the estimated tambak area development with the assumption that tambak using intensive level technology has a production capacity of 8 tons per ha per year, while tambak using semi-intensive technology will produce about 2.5 tons per ha per year. On the other hand, traditional tambak will, on the average, produce annually only 300 kg per ha.
Based upon the above assumption, the production from intensive tambak is estimated to increase from 10,000 tons in 1986 to 22,400 tons in 1996, and for semi-intensive tambak from 45,000 tons in 1986 to 180,000 tons in 1996.
4.4 Projection of Shrimp Feed Requirement
Based on practices which are ordinarily carried out well by farmers and shrimp tambak operators, the amount of feed given in an intensive tambak does not differ that much from that given to semi-intensive ponds, that is a conversion rate of 2 : 1 (2 kg of feed is required to produce 1 kg of shrimp). The amount of feed required is then estimated to increase from 110,670 tons in 1986 to 140,655 tons in 1988 and lastly to reach a 207,812 tons in 1996.
5. ESTIMATES ON NUMBER OF FEEDMILL REQUIRED
The shrimp feed requirement in Indonesia together with available capacity (both local and imported) is shown as follows:
Table 1. Projected shrimp feed demand and supply in Indonesia, 1986–1996 (in 1,000 tons).
* Assumption: supply constant at 1986 capacity.
Based on the assumptions made, it can be seen in Table 1 that in 1988 there was a shortfall in shrimp feed for the tambak industry, in the amount of 45,000 tons. This shortfall in shrimp feed supply is estimated to reach 102,000 tons by 1996, based on the increase in shrimp culture areas.
Furthermore, the said shortfall, will be filled by additional supply from local feedmill production or from imports, depending upon the competitive strengths which is mostly determined by quality and price. Along this line, even if locally produced feeds are capable of competing with imports in terms of price, this still cannot guarantee a market. From past experience, it can be said that imported feed furthermore has already dominated the domestic market because there is a greater confidence in its quality.
6. POTENTIAL OF LOCAL SUPPLY TO COMPETE AGAINST IMPORTS
In order to reduce the risks in an uncertain shrimp market situation, it is believed necessary to learn what level of technology ought to be applied in shrimp culture. In this regard, it is necessary to consider two things, as follows:
If analyzed, the first possibility would be easier to do, since the production risks will be reduced, rather than to use a culture process with a production cost that is higher than the income received. Conversely, the second alternative has a higher risk, first of failure due to the use of feed with unsatisfactory quality. On the other hand, if successful, the profit it gives will certainly be bigger.
With the assumption that the quality of feed is satisfactory and can be maintained, the second alternative is an opportunity for the local feed industry to seize the market in Indonesia. On one hand the use of imported feed at a high price (above Rp. 2,000 per kg), does not necessarily mean satisfactory profit for the grower with the present head-on selling price of Rp. 7,500 per kg. On the other hand, the lowering of selling price for feeds is also not easy because of transport costs, customs duties, storage fees, and profit margin for the importer which as a whole can reach about 30 per cent of selling price.
With the assumption that production costs of local shrimp feed can be lowered to the same level as the production costs for imported feeds, the said local feed will have a stronger potential to compete in the market especially if the imported fish meal with a high quality (like white fish meal) can be made available, among the feedmill operators.
From the result of the analysis, in the implementation of semi-intensive culture (with a target production of 2,500 kg/ha/year), if the feed costs can be made lower than Rp. 2,000 per kg, then the production costs can go down from Rp. 6,500 per kg to Rp. 4,200 per kg. With that, a standard price(floor price) can be established at a particular shrimp market level.