5. ECONOMICS OF SHELLFISH PRODUCTION

Under present circumstances, the shellfish industry is a viable business. Prices are stable and there is no apparent oversupply. The local demand seems to be able to contain present production. There is a small amount of export but this is generally confined within the region. The carpet shell or short-necked clam (Paphia undulata) has a good demand in Japan and small amount of green mussel, cockle and oyster, either fresh or processed, find their way to the Singapore and Hong Kong markets.

5.1 Market prices

For marketing purposes, the green mussel and oyster are sold fresh on-shell or shucked (clean). These are also preserved and sold as bottled product. Cockles are sold only fresh on-shell or bottled preserved while horse mussel is only sold fresh, either on-shell or shucked.

The prevailing prices in the retail markets in Cholburi and Chachoengsao provinces in June 1977 were as follows:

5.2 Prospectus of shellfish farming

5.2.1 Oyster culture

- an analysis of the economic viability of oyster farming in Thailand is shown in the following prospectus on a 4 rai (6 400 m²) project:

5.2.2 Green mussel

- the probable prospectus for a one-hectare green or sea mussel farming venture is as follows:

5.2.3 Horse mussel

- the probable prospectus for a one-hectare horse mussel farming is as follows:

5.2.4 Ark shell (cockle)

- the probable prospectus for a one-hectare cockle farming project is as follows:

5.3 Diversifying the utilization of shellfish products

The main use of shellfish at the moment is for human food. With the very high potential for increased production through a properly supported programme, more ways to utilize shellfish products need to be looked into. The duck population in the country and particularly that in the maritime provinces where the supply of shellfish is available is a good outlet for the shellfish crop. From a total duck population of about 4 million in 1970 this figure rose to 9 million in 1972 and further increased to 12.5 million in 1976. Of this duck population about 20 to 40 percent comes from the maritime or coastal provinces which have to depend on shellfish as the major supplement for feed.

The reported duck population figures for 1970, 1972 and 1976 are shown below:

¹ The maritime provinces include Chachoengsao, Cholburi, Samut Sakhorn, Petchaburi, Samut Prakharn, Samut Songkhram and Surat Thani.
² The other duck producing provinces are Chieng Mai, Burirum, Udonthani, Sakhon Nakhom, Phra Nakhom, Mahasarakham, Phattalung, Nakhorn Pathomand Chiengrai.

Trash shellfish costs about Baht 2 per kg. It is reported that each duck during its rearing time until it is sold in the market, which approximates 500 days, one duck consumes at least 10 kg of shellfish feed or equivalent to Baht 20 per duck. Even granting that only the maritime provinces use shellfish in their duck feeding, the duck population in the maritime provinces would have utilized 29 500 tons valued at Baht 59 million (US$2 950 000) in 1976. This would perhaps be mostly horse mussel but undersized green mussel, cockles and other shellfish are also used. Based on the above calculations, the ever growing duck industry appears to be a suitable outlet for the increased production of shellfish.

There may be other possible uses such as for larval feed in fish and crustacean hatcheries should this activity expand to commercial scale in the region. Figueras (1976) mentioned that in Europe mussels are used as fishing baits and fertilizer.

5.4 Product development and quality control

Most shellfish used for food are taken fresh. However, there are a number of indigenous ways of processing shellfish presently in existence in the country. These are not standardized and very little is known about them.

One of these products is dry salted shellfish. This is used for sea and horse mussel, piddock, angel's wing and razor clam. The process essentially consists in soaking shucked shellfish meat in 2 to 3 percent brine for a definite period depending on the kind and size of meat. The brined meat are subsequently flushed with fresh water and dried in the sun.

Pickling is used for sea and horse mussel, cockle, oyster, carpet shell and wedge shell. Pickling is done by using a mixture of brine, vinegar and spices including ginger and hot pepper. The pickles are reported to be bottled in 15 percent brine. Properly done, bottled pickles of the shellfish have been found to keep for a long time. Again the process used is not standardized and can vary from place to place and at various times.

Small amount of canning on short duration for exported oyster and carpet shell is being done presently. First the shucked meat are cleaned and soaked in 2 to 3 percent brine solution. After chilling, the cans are sealed and labelled for export to places like Singapore, Hong Kong and Japan.

Appetizers or seasoning products are being prepared from most shellfish meat. These are prepared by partially drying the meat then frying and roasting them with sugar and salt to taste.

There is no report of quality control actively being done for shellfish meat either fresh or processed. No purification process is also being done in the country at the moment. As mentioned the present practices are indigenous and not standardized as a specific commodity in the market. Specially with regard to shellfish, great concern is being given to the possibility of contamination by pathogens. Shellfish also have the inherent capacity to accumulate deleterious chemicals from their food or the environment. All these underscore the need for the initiation of quality control and sanitary treatment of shellfish products. In reviewing the practice of shellfish purification, Furfari (1976) stated that the process is an integral and mandatory part of the shellfish industry in England, France and Spain.

5.5 Marketing and distribution

Most of the produced shellfish is consumed locally; only a small percentage is exported. According to the 1973 Thailand Fisheries Record issued by the Department of Fisheries, data for dried mussel exports in recent years were as follows:

Besides other countries this report mentioned that Hong Kong and Singapore are the main recipient countries. Other crustacean and molluscan products in fresh, chilled, frozen, and salted in brine and dried form are also reported to be exported to Malaysia, United States and Japan. The type of mollusc product and specific amount is not segregated from the crustacean part, but the combined amounts during the period are as follows:

While the country exports some shellfish products, it also imports other shellfish commodities. For instance, the imports for ark shell or cockles during the corresponding period are summarized below:

* Included under other items

For other molluscs combined with other crustaceans, but amounts not specified (fresh or preserved), the imports were as follows:

Preliminary studies on the channel of distribution in the marketing of locally consumed and exported shellfish products is represented by the following diagram:

It is worth noting that the major part of production is channeled to the wholesaler and reaches the consumer (local or foreign) after two or three changes of hands. It seems that for shellfish marketing and distribution, the wholesaler and middleman play major roles and subsequently the producer would be very much dependent on them for the disposal of their product.