Acoustic target strength (TS) measurement and theoretical acoustic scattering models were applied to estimate the TS for assessing the fish biomass. TS measurement was made of ex situ sailfin sandfish Arctoscopus japonicus at 70 and 120 kHz, and then compared to backscatter model prediction. The live sandfish was tethered in seawater using monofilament lines. Measurements were made versus incidence angle, −50° to 50° relative to dorsal aspect directions. Distorted wave Born approximation (DWBA) model was used to calculated TS pattern. The TS values of sandfish (body length: 16.2 cm) at 70 and 120 kHz were ‒66.94 dB and ‒64.45 dB, respectively, and were about 20 dB lower than TS of other fishes in Korea waters. These TS levels were distributed within the range of the theoretical TS. Ex situ measurement and theoretical TS may be applied to improve acoustical detection and biomass estimation of the sandfish, and is necessary to measure with various lengths.

• 이형빈 | Hyungbeen LEE
• 이경훈(국립수산과학원 자원관리과) | Kyounghoon LEE (Fisheries Resource Research Division, National Fisheries Research & Development Institute, Busan 619−705, Korea) Corresponding author
• 윤은아(국립수산과학원 자원관리과) | Eun-A YOON (Fisheries Resource Research Division, National Fisheries Research & Development Institute, Busan 619−705, Korea)
• 황강석 | Kangseok HWANG
• 최정화 | Junghwa CHOI
• 박태건(국립수산과학원 자원관리과) | Tae-Geon PARK (Fisheries Resource Research Division, National Fisheries Research & Development Institute, Busan 619−705, Korea)