Acoustic Target Strength of the Endangered Chinese Sturgeon (Acipenser sinensis) by Ex Situ Measurements and Theoretical Calculations

Applied Sciences

卷:8

Myounghee Kang¹  Chongrui Wang²  Hui Zhang³  Chengyou Wang³  Qiwei Wei³  Jinming Wu³  Junyi Li³  Hao Du³ 

[1] Department of Maritime Police and Production System, The Institute of Marine Industry, Gyeongsang National University, Tongyeong-si 53064, Korea;

[2] Fisheries Research Institute of Hunan Province, Changsha 410153, China;

[3] Key Laboratory of Freshwater Biodiversity Conservation, Ministry of Agriculture and Rural Affairs of China, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China;

关键词: Acipenser sinensis;    target strength (TS);    acoustic backscatter;    echosounder;    Yangtze River;   

DOI  :  10.3390/app8122554

来源: DOAJ

【 摘 要 】

The Chinese sturgeon, Acipenser sinensis, is a large anadromous and highly endangered protected species. The assessment of its breeding population in the Yangtze River is critically important for effective management and population preservation. Currently, hydroacoustic methods have been widely used to study the adult sturgeons in the river, whereas the acoustic target strength (TS) characteristics of the species have not been studied. In this study, the TS of Chinese sturgeon was carefully evaluated both by ex situ measurements and theoretical calculations. Six Chinese sturgeons (Body Length (BL): 74.0−92.6 cm) were measured by a 199 kHz split echosounder in a 10-m deep net cage. The computed tomography of a Chinese sturgeon (BL: 110.0 cm) was conducted and the Kirchhoff ray mode (KRM) method was used to estimate the theoretical TS. As a result, the mean ex situ TS range of the six specimens was from −26.9 to −31.4 dB, which was very close to the KRM estimation (~1 dB difference). Then, the KRM method was used to predict the TS of Chinese sturgeon as a function of BL in six frequencies commonly used in freshwater environments and to estimate the TS of a representative adult Chinese sturgeon (250 cm) as a function of frequency and tilt angle. This study can provide a good basis for future hydroacoustic studies on the critically endangered Chinese sturgeon.

【 授权许可】

Unknown