The existing stock ranges in size from 100 to 900 g. It is, therefore, recommended that fish of 600 g and above should be marketed. The purpose of this recommendation is threefold. Firstly, the market demand within the states of Trengganu and Kelantan could be evaluated. Secondly, the procedures of fish handling and transportation could be demonstrated to the team and the counterpart by the master fish farmer. Thirdly, this harvesting arrangement would enable quicker turnover of the stock and maximize the utilization of the given volume of water. It would also facilitate the sorting of the existing stock by size ranges and species thereby reducing stresses on the smaller fish. The slow growing species within the existing stock, such as the Russel's snapper should be kept in separate cage(s) so that practical feasibility and economical viability study could be carried out. For each of the species, its optimum-value size should be clearly established for the various markets.
A work programme for the master fish farmer during his stay in Malaysia was discussed and prepared as shown in APPENDIX B. With the aid of the counterpart staff, he should direct his effort into the formulation of a management scheme for the fish farming project, as well as into the capture of fish seeds to be used as new stocks.
It was observed that the bulk of the existing stock averaged 150 g per fish. Working with a target stocking density of 10 to 15 fish per m3, and a growth period of eight calendar months, the potential yield of the existing facility, i.e. cage volume of 219 m3, could be 1 643 to 2 464 kg at an estimated daily increment of 2.5 g per fish. This indicated a yield of 7.5 to 11.25 kg per m3 in ten months. At harvest, the fish should have an average size of 0.75 kg (ca. 1.2 catties/fish). This calculation has been based upon a daily feed input of 5 percent of the total biomass; and the effects of the monsoonal weather have not been taken into consideration. In this connection, adverse effects of the northeast monsoon caused by shortages of fish feed should be contemplated. The possibility of developing a pellet feed should therefore be looked into. This pellet may be used for feeding the stock in cases of unavailability of the trash fish during the monsoon season. On the other hand, it may be used as a dietary supplement to the trash-fish diet, in which certain vital elements have been proved to be deficient. This development may also be used as pioneer work in the development of a more efficient substitute that will eventually replace the trash-fish diet. The determining factor is one of viability in relation to the potential net profit level of this potential commercial engagement.
Basing on estimates made in paragraph 5,3, a second crop of a similar yield to be stocked in February 1979, could be available for harvesting in September 1979. This is to assume that the availability of fry and fish feed would present no problem to the operation within the area.
With the growth of cage culture activities, it should be anticipated that the demand for fry would be markedly increased. This would lead to an increase of fishing pressure on the natural population of the species in the lagoon, resulting in a possible depletion of their stocks if proper management scheme was not introduced. On the other hand, with the lagoon being a natural spawning/nursing ground of potential culture species, conservation of the broodstock population and the natural environment of the lagoon should also be enhanced with the advent of the project. This would require a separate survey by fishery biologists and ecologists on a comprehensive scale to provide the necessary information for future decision taking.
