Species composition and cluster analysis of the communities caught by dredge in relation to tooth spacing and mesh size in the coastal waters of Gangneung, Korea

Abstract

The dredge gear is dragged along the bottom of the sea to catch targeted edible bottom dwelling species. Species composition and ecological index of the catches of dredge were estimated around Gangneung coastal fishing ground by dredge with different mesh size and tooth space from July to December 2013. Eight different types of dredge including four different tooth space (24.7 mm, 29.9 mm, 34.9 mm, 40.1 mm) and four different mesh size(15.5 mm, 32.7 mm, 51.1 mm, 60.0 mm) were used in the experiment. During the experiment, total catches were collected 31 species as sipunculida 1 species, mollusca 13 species, annelida 3 species, arthropoda 8 species, echinodermata 4 species and others 2 species. The dominant genus were mollusca and echinodermata while the dominant species were Megangulus venulosus, Pseudocardium sachalinensis, Schaphechinus brevis. The richness index was ranged 1.29-1.72, evenness index was 0.6-0.65 and diversity index was 1.65-1.83 according to the tooth space and mesh size of dredge. Richness index, diversity index were high at tooth space 34.9 mm dredge and ecological index showed decreasing tendency with the increasing of mesh size of dredge.Cluster and MDS analysis, based on a Bray-Curtis and similarity matrix of fourth root transformed data of number of species and wet weight, showed division into four different groups as four different tooth space (Group A), four different mesh size Group B (51.1 mm, 60.0 mm), Group C (32.7 mm) and Group D (15.5 mm).

Influence on the catch of shellfish by offshore dredge fishery according to change fishing area to the construction of the Samangeum Dike in Jeollabuk-do, Korea

“…의 개발에 관한 연구 (Cho and Ko, 1994a;1994b), 황해 의 충남 연안에서 형망으로 조사된 저서무척추동물의 분포 (Je et al, 1991), 피조개 형망의 어획선택성에 관한 연구 (Kim, 1999), 민들조개 (Gomphina melanaegis) 형 망의 갈퀴에 의한 어획선택성 (Park and Kim, 2000), 형망어구에 대한 민들조개의 어획선택성 (Cho et al, 2001), 경상북도 영일만에 분포하는 이매패류의 자원조 사 (Cha et al, 2012), 강릉연안에서 형망의 갈퀴 간격 및 망목 크기에 따른 어획 생물의 종조성 및 군집분석 (An et al, 2014), 포항 영일만 형망어업의 어획 및 혼획 실태 (An et al, 2015)와 영일만 형망어업 어획물의 종조 성 및 분포 특성 (Hong et al, 2016 Schaefer, 1954).…”