Design optimization of survey sites of fishery resources in the coastal waters of southern Zhejiang

YANG Hanyun; QIN Song; GAO Chunxia; MA Jin; ZHAO Jing

doi:10.13984/j.cnki.cn37-1141.2025.04.024

Abstract：To investigate the influence of the number of sampling stations on the accuracy of the fishery resource survey along southern Zhejiang offshore,the influence of the number of stations on fish com-munity resources,the absolute dominant species resources and the species detection rate in each season was compared based on bottom trawl survey data in southern Zhejiang offshore in February,May,Au-gust and November,2019,with computer simulation methods,and the optimal number of stations for fishery resource survey in southern Zhejiang offshore was estimated.The results showed that seasonal differences significantly affect the sampling accuracy of fish communities with the same number of sites.The seasonal coefficient of variation(CV)of fish richness sampling ranged from spring to au-tumn and then to winter and summer,and the relative estimation error(REE)and relative bias(RB)varied seasonally,autumn was larger than spring,then winter and finally summer.The species detec-tion rate was also different seasonally,therefore,different numbers of stations were required for the detection rate of a species among different seasons.Changes in studying population influenced the opti-mal number of sites.In spring,the ranges of variation of CV,REE and RB of Trichiurus lepturus were significantly wider than those of Benthosema pterotum,and the optimal number of sites should be ad-justed according to the actual survey needs.Under the premise of choosing REE=10％as the asymp-totic value for determining the optimal number of sampling sites,and by considering the quantified re-sults of community resources,community dominant species resources and species detection rate each season,the optimal number of offshore sites of trawl fishery resources in southern Zhejiang was 27 in spring,24 in summer and autumn and 26 in winter.