Fisheries and Aquatic Sciences

The Korean Society of Fisheries and Aquatic Science (한국수산과학회)
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A study on the multi-frequency acoustic target strength of krill using a stochastic distorted-wave born approximation (SDWBA) model

  • Wuju Son (Division of Ocean & Atmosphere Sciences, Korea Polar Research Institute) ;
  • Wooseok Oh (Institute of Low-Carbon Marine Production Technology, Pukyong National University) ;
  • Hyoung Sul La (Division of Ocean & Atmosphere Sciences, Korea Polar Research Institute) ;
  • Kyounghoon Lee (Division of Marine Production System Management, Pukyong National University)
  • Received : 2023.10.14
  • Accepted : 2023.12.26
  • Published : 2024.04.30
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Abstract

We examined the dB difference in target strength at multiple frequencies (ΔTS) for the identification of Antarctic krill (Euphausia superba) and ice krill (Euphausia crystallorophias) using a stochastic distorted-wave Born approximation model. Our investigation focused on ΔTS patterns at multiple frequencies in relation to size, along with key acoustic properties influencing TS, including density and sound speed contrast, fatness, and orientation. The findings revealed that the orientation and fatness significantly affect the ΔTS patterns. The results provide insight into the importance of the multi-frequency technique for estimating krill biomass and their ecological interactions with environmental features in the Southern Ocean.

Keywords

Acknowledgement

This research was supported by the Korea Institute of Marine Science & Technology Promotion (KIMST) through funding provided by the Ministry of Oceans and Fisheries (KIMST-20220547, PM24060), and by the Korea Polar Research Institute (KOPRI) through a grant funded by the Ministry of Oceans and Fisheries (KOPRI PE24110).

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