Variations in species composition of fishes caught by trawl survey in the northwestern East Sea of Russian EEZ and southwestern East Sea of Korean EEZ
To examine species composition, abundance and biomass of fishes in the northwestern East Sea of Russian EEZ, trawl survey were conducted at 31 sampling stations from 2006 to 2008. Also, trawl survey were conducted at 21 sampling stations in the southwestern East Sea of Korean EEZ from 2006 to 2008. A total of 67 fishes were collected in the northwestern East Sea of Russian EEZ, a total of 39 fishes were collected in the southwestern East Sea of Korean EEZ. Among them, a total of 53 fishes were collected in the northwestern East Sea of Russian EEZ only, and a total of 25 fishes were collected in the southwestern East Sea of Korean EEZ only. Mean abundance per area which caught by trawl survey in the northwestern East Sea ranged from a high of 116,478 inds./km2 in 2008 to a low of 19,737 inds./km2 in 2006. And mean abundance per area in the southwestern East Sea ranged from a high of 89,129 inds./km2 in 2006 to a low of 8,234 inds./km2 in 2008. Mean biomass per area which caught by trawl survey in the northwestern East Sea ranged from a high of 11,333 kg/km2 in 2008 to a low of 2,439 kg/km2 in 2006. And mean biomass per area in the southwestern East Sea ranged from a high of 6,273 kg/km2 in 2006 to a low of 1,062 kg/km2 in 2008. Cluster analysis, based on a Bray–Curtis similarity matrix of fourth root transformed data of number of species and individuals per area, showed division into three different groups by depth in the northwestern and southwestern East Sea.