Hydro-acoustic survey was carried out to investigate the spatial characteristics of fish distribution near two artificial reefs (AO: large octagonal semi-sphere and AC: combined custom built) having different types in Jeju marine ranching area. The survey system consisted of scientific echo sounder (EK60), DGPS system, and ECDIS (Mecys). Field survey was conducted on August and October 2012 with star survey and line transect survey line method, and species composition was investigated from gill net fishing survey. The acoustic signals from individual fishes and small fish schools were mainly recorded around AO, but large and strong signals from large fish school were mainly detected in the top layer of and the water column near AC. The echogram suggest that the fish aggregation for the two types of AO and AC exist the significant difference in fish species and spatial distribution pattern.

• 황보규(군산대학교 해양생산학과) | Bo-Kyu HWANG (Dept. of Marine Science & Production, Kunsan National University, Gunsan 573-701, Korea)
• 장호영(군산대학교 해양생산학과) | Ho-Young JANG (Dept. of Marine Science & Production, Kunsan National University, Gunsan 573-701, Korea) Corresponding author