The outcome of the present midwater trawling trials are very encouraging indeed for the development of a commercial fishery on B. pterotum in the Gulf of Oman.
The proposed Mesopelagic Fishery Pilot Project in the Western Arabian Sea will be the next phase should the governments involved consider it mutually beneficial to develop this commercial fishery. Operation of the pilot project will require about US$ 13 million and the technical details are described in a draft project proposal.
In view of the trial results, some changes in the draft project proposal are considered desirable.
The fish abundance and distribution observed during these trials indicate no hope for commercial purse seining. It is, therefore, recommended to delete purse seining trials from the work programme.
The trials have further shown that one-boat midwater trawling is quite satisfactory. It is, therefore, recommended to give this technique highest priority. Consequently, there should be only one project vessel, i.e., a medium size stem trawler with chute, about 45 m long with a main engine of about 1200 HP and controllable pitch propeller. A propeller nozzle would be desirable.
In order to save sailing time (possibly daily to and from harbour and fishing grounds), to avoid or at least reduce problems with spoilage of the catch and to make the vessel completely independent from so far largely missing shore based fish meal and oil factories, it is strongly recommended that the project trawler should be equipped with a fish meal and oil factory with a capacity of about 150 t of raw material per day. She should further have two raw material bunkers of about 50 t capacity each and a hold capacity for fuel and other supplies and for the processed products for about a one month operation.
Such fish meal trawlers have been, and some may still be, operating in the North Sea and the North Atlantic, e.g., from Norway and Spain. Another possibility could be to convert one of the USSR SRTM trawlers available in the People’s Democratic Republic of Yemen. Other medium size trawlers could be chartered, or even purchased, and converted from the surplus trawler fleet in northern and western Europe. If the pilot project is successful, the sale of the trawler to one of the coastal countries might be possible. In any case, the proposed change of vessel would hardly exceed the present budget, but may rather allow some savings (e.g., items 30.39 and 70).
It is recommended that the vessel should have the following equipment and instrumentation: radar, satellite navigation, electro-magnetic log, auto-pilot, engine and propeller control directly from the wheelhouse, ship’s fishery echorecorder, up-and-down netsonde with cable, medium to large searchlight sonar and scientific echointegration system for abundance estimation. A real multinetsonde with additional transducers for measuring opening width and for observing fish behaviour further aft in the net, and an amount of catch indicator system would be desirable.
In addition to a powerful trawl winch, which would enable hauling-in the warps during towing, the vessel should have at least one net drum with a maximum pull of about 10 ton-force at a hauling speed of at least 1 m/sec. The fishing deck should allow hauling up catches up to about 30 t. A submersible fish pump with crane should be provided to handle larger catches.
Pair midwater trawling is less convenient and in certain respects inferior to one-boat midwater trawling. It is recommended to give pair trawling second priority but to make provisions in the budget for chartering vessels periodically if desired.
In view of the work load and unforeseen changes in operational pattern, it is strongly recommended to supplement the staff by one fishing technologist (P-4), one echosounding (scientific) specialist (P-3) and one electronics specialist (P-3). The fishery biologist (P-4) must, naturally, have good experience in acoustic stock assessment.
In view of the proposed changeover from shore-based to ship-born meal and oil processing, a modification of the post of processing superintendent (P-5) to processing engineer (P-4) may be suggested. Also the marine and engineering superintendent (P-5) post could possibly be combined with the post of project manager (D-1), but these suggestions are actually outside the scope of this report.
Recommendations for major targets of the work programme in fishing technology have already been made in the text.
