Study on Acoustic Characteristics of Pseudobrachial Sakura Krill

Abstract

As a widespread species in the Southern Ocean, pseudobrachial Sakurapill has relatively high abundance and relatively uniform distribution. The acoustic data for this study were obtained from the scientific fish finder (SIMRAD EK60) aboard the Xuelong polar research vessel, which operates at 120kHz. Biological sampling was obtained from vertical trawl sampling of zooplankton from 200m to the surface, and acoustic data processing was performed in the specialized software of the Institute for Underwater Acoustic Survey and Analysis of Biological Resources (ECHOVIEW 6.1.72, MYRIAX, AUSTRILIA). The study of acoustic features is carried out by using the comparative method. It was found that at 120 kHz, most of the SVS of pseudobrachinus were distributed between -107.63 dB and -87.25 dB, and the peak value was between -93.88 dB and -92.50dB. The Ts were mostly distributed from -99.75 dB to -63.75dB, showing obvious bimodal structure.