Towing resistance of ottar [i.e. otter] trawls used for shrimps from small mechanised boats

Attempts have been made to determine the towing resistance of the shrimp otter trawls operated from small trawlers off Cochin and the actual resistance on the warps for eight different boats working under the normal fishing conditions have been measured. Engine Horse Power utilised for towing the gear at normal speed and fishing conditions has also been estimated.

Bacterial flora of marine fish doma (Sciaenoids) (Small spp.) from Bombay coast

Marine fish doma (Sciaenoids) (Small spp.) from Bombay coast was studied for total bacterial counts on the surface and gut. Large number of Micrococcus species (77.4%) was found whereas few species from Achromobacter, Bacillus, Bacterium, Flavobacter, Pseudomonas and Sarcina were noted.

On the operation of small shrimp trawls in shallow waters-scope-ratio and size-depth relation

Studies on small trawls seem to be comparatively less. These trawls are generally operated in shallower waters, where due to the limitations in the length of warp that could be released, size restrictions have to be considered for their efficient functioning. An attempt has been made to assess the effective scope-ratio of length of warp required for the operation of trawls at shallower depth and to a judge the size of trawl suitable for use at lower depths.

Scantlings for small wooden fishing vessels

Studies are carried out to find a suitable basis of specifying scantlings for wooden fishing vessels for India, especially for the range 30' to 50' length overall. Equations of the type y=a (where 'y' is scantling in inches, N is cubic numeral in ft³ and 'a', 'b' are constants) are fitted to the scantling tables (applicable to vessels 50’ and above) available from USA, Newfoundland, Denmark, France and Scotland and they are found to represent the regulations accurately. These lines are corrected for standard frame and beam spacing and molded/sided dimensions to bring them on a common basis for comparison and minimum scantling lines for the main structural members are derived. These lines are extended to cover the range 30' to 50' which is generally outside the range of the above regulations.

Nutritional value of some small indigenous fish species (SIS) of Bangladesh

Twenty three small indigenous fish species (SIS) in the size range of 3-18 cm were analyzed for proximate composition and minerals (Ca and P) content to evaluate their nutritive value. The moisture content of different species ranged between 71.00 and 81.94%. In general, small sized fishes showed higher moisture content. The muscle protein content among the species varied widely (16.16-22.28%). In general, the muscle protein content of fishes showed higher value than the whole carcass protein content. The carcass lipid content varied between 1.87 and 9.55% and showed an inverse relationship with the moisture content. The gross energy content ranged from 19.51-27.30 KJ/g on dry matter basis. In the present study, the calcium and phosphorus contents ranged between 0.85-3.20% and 1.01-3.29% respectively. The calcium and phosphorus ratio (Ca/P) varied between 0.44 and 2.00. From the nutritional point of view, it shows that the SIS are good source of protein and minerals especially calcium and phosphorus

A small scale fish meal dryer

A batch type rotary drum dryer for the production of fish meal suitable for operation in the fishing villages of India has been designed, fabricated and operated successfully. The dyer can be used for production of fish meal from whole lean fish or press-cake from fish body oil extraction plants. The time taken to reach a moisture level below 10% is 5-8 hours depending upon the type of material fed into the dryer.

Small scale manufacture of crude agar from Gracilaria seaweeds

A simplified process was worked out to prepare crude agar from red seaweeds (Gracilaria sp.). The process required careful preliminary cleaning and bleaching (sun-drying) of the weed. The agar was extracted by boiling with water in a mixture (2%) strong enough to set as a jelly. Freezing the jelly over a 3—day period in an ice-making machine, adjusted to work slowly, separated out ice and agar. The blocks were thawed out and the agar dried in the sun. The efficiency of extraction was over 800/A.

Small mesh trawling

Experimental trawling operations for bottom fish were first begun in 1920 and consisted of surveys of the continental shelf around Ceylon and the west and east coasts of India. These preliminary surveys showed that the continental shelf of Ceylon was either very poor in bottom fish or that the ground was so rough that trawling has proved to be economically not sustainable (Malpas, 1926). Although a considerable amount of trawling has been carried out using small-meshed trawls, there is no record of the details of the gear used or any account of the relative efficiency of the different designs of trawls used in the operations. Experimental operations were, therefore, carried out off 80 h.p. boats such as m.f.v. Canadian and North Star, to select the most effective gear for these boats. In more recent times experiments were also conducted to select the most effective trawling gear for the 11-Ton boats of the Ceylon Fisheries Corporation. The results are reported in this publication.

Biology, stock size and catch of small pelagic fish along the coast of Mozambique

A compilation of all the available information on the main small pelagic fish resources of Mozambican waters is presented. Resource data on distribution areas, reproduction, age, growth and stock size are described. Actual catch and catch per unit of effort of the commercially exploited stocks are also given. Results of the preliminary assessment of the stocks of scad and mackerel and the problems involving the assessment of Kelee shad stock at Maputo Bay are discussed.

Results of a random stratified bottom trawl survey for scad and mackerel stocks in Mozambican waters: small pelagic fish December-January 1985

The results obtained during the third phase of Nauka are reported concerning the standing stock estimates, population length structure and gonad development of scad and mackerel stocks and the catch composition in Mozambican waters.