The objective of this study was to provide fundamental information on fish swimming behavioral properties. Acoustic data was collected at nighttime from the 10th to 12th March, 2016 near Yokji Island in the South Sea of South Korea, and was analyzed using the fish track technique. This technique is to identify groups of single targets, which shows a pattern of systematic movement. As a result, the differences of the behavioral properties such as depth, swimming speed, vertical direction, horizontal direction, tortuosity, and depth change among days were minor; however, statistical results (Welch analysis of variance) showed significant difference between days. Especially, the target strength (TS) of the 11th were significantly different from the 10th and 12th. It could be assumed that gizzard shad, which was the dominant species from the catch on the 11th March, might have affected this difference. The correlation between TS and other properties was very week. The significant difference seemed even small differences of average values because of the large data volume.

• 최정화(국립수산과학원 수산자원연구센터) | Jung Hwa CHOI (Fisheries Resources Research Center, National Institute of Fisheries Science, Tongyeong 53064, Korea)
• 박준수(경상대학교 해양경찰시스템학과/해양산업연구소) | Junsu PARK (Department of Maritime Police and Production System/Institute of Marine Industry, Gyeongsang National University, Tongyeong 53064, Korea)
• 박준성(경상대학교 해양경찰시스템학과/해양산업연구소) | Junseong PARK (Department of Maritime Police and Production System/Institute of Marine Industry, Gyeongsang National University, Tongyeong 53064, Korea)
• 강명희(경상대학교 해양경찰시스템학과/해양산업연구소) | Myounghee KANG (Department of Maritime Police and Production System/Institute of Marine Industry, Gyeongsang National University, Tongyeong 53064, Korea) Corresponding author