On the estimation of yield from exploited marine stocks with reference to south-east Asia

Abstract

Accurate estimates of yield and eflfort are necessary for a proper apraisal of exploited stocks. In the South-east Asian region where fishing is of a diffused nature and landings are by indigenous boats all along the coastline using various types of gear, complete record of catch and effort is impossible and a suitable sampling scheme for their estimation is the only logical alternative. The various factors influencing the choice of a sample design Imve been discussed in relation to the existing conditions in the region. The following points in particular have been dealt with in the paper: (a) the nature of stratification, (6) the choice of units, (c) intensity of sampling and (rf) precision of estimate. The sampling design employed in India for the purpose of estimation of catch and effort has also been discussed in detail.