Journal of the Marine Biological Association of India

Volume 28 Issue 1&2

Mesh selectivity studies for management of marine fishery resources in India.

K. Alagaraja C. Suseelan and M. S. Muthu

Mesh selectivity studies on commercially important species are essential to identify the fishable segment of the stock. This is required for assessing the effect of fishing effort on the exploited stocks and suggesting effective management measures for maximum sustainable yield.

The present paper attempts to give a general review of the work done in this sphere. At centres like Kakinada (Andhra Pradesh) change in the cod - end mesh size in trawls over the years has resulted in considerable variations in production, catch composition and size distribution of commercially important species of shrimps. Instances of heavy landings of undersized prawns (penaeids less than 65 mm TL) have been noticed during the peak landing period along the coast of Kerala particularly at Sakthikulangara and it is partly attributed to the smaller mesh size of the trawls operated there. Considerable quantities of juvenile prawns of the marine species are caught from the estuaries and backwaters using stake nets having cod - end mesh sizes as low as 5 mm which in turn will adversely affect the recruitment of the species in the marine sector. Experimental studies on mesh selectivity of gill nets for oil sardine, and of trawls for shrimps in Kerala and of dol nets for Bombay duck in Maharashtra and Gujarat clearly indicate the necessity of mesh regulation for the judicious exploitation of these resources. Stock assessment studies carried out on shrimps along the southwest coast of India also emphasise the urgent need for an upward revision of the existing cod -end mesh size of 20-25 mm to at least 30mm in order to save the fishery from the danger of depletion.

Date : 31-12-1986