6. TYPE OF AQUACULTURE PRODUCTION SYSTEMS TO BE CONSIDERED WHEN DEFINING A NATIONAL AQUACULTURE POLICY

The quantity and quality of resources (men, equipment and facilities) that Government can make available for development of aquaculture, naturally depend in part on the intrinsic merits of possible culture systems. It depends as much on the alternatives available to the Government for use of the same resources.

The nature and quantity of resources that the Government can make available for aquaculture development during the next decade depends, as mentioned above, on the merits of various aquaculture systems. Several of those discussed in this report were almost unknown to senior Government officials. This meant that the study group, in the time at its disposal, could not expect government to decide on what type of culture systems that should form the back-bone of its aquaculture policy. The study group therefore proceeded on the assumption that the systems believed to have the potential to become self-sustaining would be included. It then evaluated them in an explicit manner (against Government development objectives) and ranked them accordingly. The study group felt that this procedure should enable the Government on the one hand to have a consistent policy, and, on the other to apply rationally any quantity of resources that could be made available for the purpose.

The study group was of the opinion that the likely economic viability of production units, and possible volumes of production in 1986 and 1991, would not be sufficient information for establishing a priority order, and that risks, Government development effort and likely effects on Government development objectives, should also be taken into account. This chapter describes how this was done and lists the aquaculture systems in the order that the study group believes the Government should attend to their development.

6.1 Aquaculture production systems as a means to reach Government development objectives

The study group selected the following three aspects of the aquaculture production systems as representative of Government's development objectives:

• generation of employment

• foreign exchange earnings (savings); and

• production of fish (crustacean) for local markets.

It lies in the nature of production - be it aquaculture, agriculture or industry -that whatever benefits are obtained are obtained at a cost. The costs occur in the form of the use of factors of production. Therefore, it is the achievement of Government development objectives per scarce factor or production used that is of interest, not the achievement of development objectives per se.

The availability of factors of production were discussed in section 4.4 above. It was recognized that fresh water, land and capital were scarce in the context of the Jamaican economy. So were the supply of trained aquaculturists. However, while the former are fairly easy to quantify in relation to the expected production, the need for aquaculturists is not. Thus, the achievement of development objectives is quantified in relation to the use of land, fresh water and capital. The details are given in Tables 3, 4 and 5. The following conclusions can be drawn from these tables.

With respect to employment generation, foreign exchange savings and supply of fish, raceway culture of tilapia is the outstanding alternative in the case that land and fresh water are the scarce factors of production. Culture of marine fish in pens is probably the activity which gives best returns (measured in terms of satisfying Government development objectives) against the use of investment funds.

TABLE 2: Development of self-sustaining commercial aquaculture production systems; timeframe and government inputs

¹ To improve and expand this culture system

Source: GOJ/ADCP Aquaculture Study Group

FIGURE 1

Estimated production (live weight) 1982, 1986 and 1991 in metric tons

Source: Government of Jamaica/ADCP Study Group

FIGURE 2

Estimated value (ex-farm) of production (live weight) 1982, 1986 and 1991 in millions J $

Source: GOJ/ADCP Aquaculture study group

Surprisingly, pond culture of tilapia and shrimps contribute least to employment generation. Fresh water prawn culture is a better foreign exchange saver than pond culture of marine shrimps, given the assumption that shrimps will be consumed locally, replacing imported frozen marine shrimps. If capital is the factor of production in shortest supply and foreign exchange the objective that is most important, then tilapia culture in ponds and pens has an advantage over other aquaculture activities.

Tilapia culture, in all its forms, supplies most fish for the local market. Oyster culture and culture of marine shrimps supply least fish to the local market, per scarce factor of production.

6.2 Risks associated with aquaculture production systems

All aquaculture production systems are exposed to risk. Man is a source of uncertainty, as is the climate and the heterogenous growth characteristics of the cultured stocks. As the degree and nature of risks vary from one aquaculture production system to another, the Government ought to know the risks of any one system before choosing those suitable for a Government extension effort.

The study group made an attempt to estimate the risks attached to the various typical aquaculture production systems. In that context, it classified risk into the following categories: technological, environmental, disease, predators, economic. Table 6 presents the study group's estimates of the risks.

The study group recognizes that these risk-appraisals are subjective in nature, and that a summation of the ‘total’ risk for any one system is somewhat artificial in nature. With these reservations in mind, it seems, nevertheless, that the following conclusions can be drawn from Table 6:

1. Culture of fresh water fish and fresh water shrimp is a less risky activity than culture of marine fish and shrimps.

2. Polluted waters, disease and monetary exchange rate fluctuations are the events which, if they occur, would seem to cause most damage to the culture activities.

3. The culture of tilapia in ponds and raceways are the culture systems which on the whole are the least exposed to failure through risk events.

6.3 Results of Government's projected effort to develop aquaculture production systems

The Government's projected development effort is identified in Section 5.3, in terms of the funds and the people the Government must be prepared to use in order to obtain the production levels foreseen in figures 2 and 3.

In the context of establishing Government priorities for aquaculture development, an answer should be given to the question ‘what is the most effective use of Government resources?’. They should be used in support of aquaculture activities which give a high result (in terms of achieving Government's development objectives), per unit of effort. The study group is of the view that under no circumstances should the cost of Government efforts during the coming decade exceed the gross value of the resulting production during the same period. Given the information provided in Table 2 and figures 2 and 3, it is evident therefore that the Government should not use significant portions of its own resources in the continued support of oyster culture or to develop marine shrimp culture. It would seem rational therefore to let both those activities be financed and executed by those private entrepreneurs who believe it is in their interest to pursue these activities at their own expense.

6.4 Selection of culture systems

Six aquaculture production systems have now been appraised with regard to the following:

• micro-economic results of typical aquaculture units,

• possible magnitude or production in 1986 and 1991 given a specified level of Government development effort,

• risks, and

• influence on Government development objectives.

TABLE 3: Estimated employment generation of typical aquaculture units

Source: GOJ/ADCP Aquaculture Study Group

TABLE 4: Estimated foreign exchange earnings (savings) of typical aquaculture units

¹ Infinity, as little or no fresh water is used.

Source: GOJ/ADCP Aquaculture Study Group

TABLE 5: Estimated production of fish, shrimp or bivalves by typical aquaculture units

Source: GOJ/ADCP Aquaculture Study Group

TABLE 6 : Estimated risks associated with aquaculture production systems

¹ Initially the risk associated with seed production would not be borne by Jamaican producers.

Source: GOJ/ADCP Aquaculture Study Group

The appraisals, as has been seen, are not measured with the same unit of measurement. While the micro-economic analysis of possible production units measure results in Jamaican dollars, the measurement of risks are qualitative and those of influence on Government objectives are in the form of ratios (man-years of employment per J$ 10 000 investment, for example). As a result, it is difficult to obtain an overall summation. How to weigh the results of the micro-economic appraisal against those of the risk appraisal, for example?

There are basically two ways to proceed in order to obtain an overall summary appraisal of each of the systems. In both cases the judgement of an informed group of individuals is essential. The group can proceed towards a concensus with or without recourse to a formal and quantified appraisal procedure. The formal procedure would consist in assigning numerical weights to objectives and qualitative judgements and then rank culture systems according to the composite number obtained for each system. Partly for lack of time, and partly believing that the results of the two methods would be very similar, the study group arrived at its conclusion without attempting to quantify the qualitative aspects of its appraisal. Its concensus view on the ranking of production systems is as follows:

1. pond culture of tilapia

2. pond culture of fresh water prawn (Macrobrachium rosenbergii)

3. raceway culture of tilapia

4. pen culture of marine fish

5. culture of mangrove oyster.