The aquaculturist visited some fish farms to survey their stocking and management methods; the local ponds were:
overcrowded
the stocking was usually done with low genetic value carps or Indian minor carps
the ponds are rarely fertilized or manured
sometimes there is a thick layer of mud at the bottom of the ponds
(This information was later used in training of the local farmers.)
On the advice of the aquaculturist, different stocking densities were applied in the ponds of different districts, resulting in different growth and survival rates (see Appendix 6).
Analysis of survival and final weight of the fish, and results of the control harvesting (to be carried out by the Assistant Fishery Development Officer to check the fish growth), will give valuable indications for future stocking.
A short pamphlet describing the technology for the correct operating of small ponds was prepared and translated into the Nepalese language spoken in the southern part of the country. This pamphlet was distributed to the farmers (see Appendix 7 for English summary).
The aquaculturist organized a four-day training course for the farmers in Gaylegphug district, together with the National Project Manager and Assistant Fishery Development Officer.
On request of the Tripartite Review Meeting, the production of market-size fish production was initiated. Each pond (0.37 ha) was stocked with 2 500 fingerlings with an average weight of 4 g. The pond was manured and the fish were fed with rice bran until they reached 30 g average weight, and then with a mixture of rice bran and mustard oil cake (see Fig. 3).
The other ponds (F1, F2, N5) were stocked for market-size fish production in a total area of 0.74 ha.
Due to the high temperatures in southern Bhutan and the lack of cooling facilities, storage and transport of live fish was difficult. To avoid the quick spoilage of fish, smoking seems to be a suitable method.
The aquaculturist constructed a small Altona-type fish smoker and trained the interested local staff in smoking procedures (see Appendix 8).
Following the decision of the Tripartite Review Meeting construction of the Centre was continued in May. According to the plan of the aquaculture engineer the D2 drainage canal was dug, but the work soon had to be stopped, because the Government blocked the budget. The National Project Manager and the Director of Animal Husbandry Department requested permission to continue construction, but at the time of the aquaculturist's departure, no answer had been received. Using plastic nets, brought from Hungary, construction of the hatchery filter was completed. The installation of the hatchery was begun, to be completed by the Assistant Fishery Development Officer.
The aquaculturist also prepared a plan for the pigsties (Appendix 7), but had no opportunity to build them.
Subcentre
As the request of the FAO Regional Fisheries Officer and the Director of the Animal Husbandry Department the aquaculturist visited Bangtar Valley in the southeast of the country to evaluate the possibility of construction of a subcentre.
Depending on soil quality and water supply, three sites seemed suitable for pond construction. On the right side of the river at Lower Maushi Tar, near the irrigation canal there is a suitable place for the construction of barrage-type ponds. On the left side of the river there are two potential sites, Bakulay and Dumpha for construction of bigger ponds.
Unfortunately, on the above-mentioned areas there are paddy fields; in fact the aquaculturist found that all areas in the valley of watertight soils are used as paddy fields. But, due to the mosaic-structure of the soil in the valley, more detailed soil analyses must be carried out before choosing and purchasing the areas for pond construction. (Due to the short duration of the Restricted Area Permission, the aquaculturist could spend only one day in the valley, which was enough only to recognize its excellent potential for fish culture, but there was no opportunity for exact soil analyses.)
The aquaculturist wrote a small booklet together with the Assistant Fishery Development Officer, entitled “Fish Culture in Small-Scale Fish-Farms in Bhutan”. Given the limited education level of the people to whom it was destined, it contains many drawings of all steps of work together with a brief text. After editing the booklet and finalizing the drawings it will be translated into Dzonkha and Nepalese languages, then copied and distributed by Animal Husbandry Department (the English version is attached as Appendix 8).
