Spatiotemporal Distribution of the Catch of the Single Otter Trawl in Zhoushan Fishing Ground:Based on the Data from Logbook

Based on the statistical data recorded in the logbooks of five single trawler vessels that fishing in Zhoushan fishing ground in 2010,the spatial and temporal distribution of total catch and catches of dominant species were analyzed.The results showed that the total catch decreased in January and February,but increased from March to May.After the closed fishing season,the total catch significant increased in September.From October to December,the total catch increased firstly and then decreased.The spatial distribution characteristics were as follow: the high catch appeared within 30°18′-31°00′ N,124°18′-25°18′ E in spring.In autumn,the high catch appeared within 30°18′-31°00′ N,123°00′-123°18′ E.In winter,the high catch appeared within 29°00′-30°00′N,125°00′-125°18′E.Catch in winter was higher than those in spring and au-tumn.The temporal factors had more impact on catch than spatial factors.The dominant species including Lep-idotrigla japonica,Trichiurus haumela and Pseudosciaena polyactis,whose catch percentages were 16.88%、7.58%,4.58%.The research results indicated that season is the main factor affecting the catches of dominantspecies,the high catch season of T.haumela was spring,the high catch seasons of P.polyactis were spring andautumn,and the high catches of L.japonica were spring and winter.In view of the spatial distributions of dom-inant species,the high catch of T.haumela mainly appeared in 29°05′-31°18′N,123°00′-125°13′E,whilethose of P.polyactis,and L.japonica were mainly came from 29°00′-30°34′N,122°34′-125°34′E and 29°00′-31°10′N,123°00′-125°09′E.