南海黄斑蓝子鱼的目标强度测量研究

Target strength measurements of pearl-spotted spinefoot(Siganus oramin) in the South China Sea

2008年10月在大亚湾人工鱼礁海域的渔排上,使用鱼类目标强度测量装置,包括分裂波束式SimradEY60便携式水声学测量系统(120kHz),采用"绳系控制实验法"对16尾黄斑蓝子鱼(Siganusoramin)逐尾进行单体鱼的目标强度测量。样品鱼为在大亚湾海域现场采用渔笼捕捞的单体活鱼样品,其叉长范围为7.3～19.5cm,平均叉长为11.3cm,体质量范围为4.6～135g,平均体质量为33.2g。结果表明,南海黄斑蓝子鱼目标强度(TS)与其叉长的关系式采用常规的20lgL形式为TS=20lgL-74.1分贝。本研究采用"绳系控制实验法"对16尾黄斑蓝子鱼逐尾进行单体鱼的目标强度测量,旨在为提高渔业资源声学调查与评估的准确性提供数据支持。

Based on the taking advantage of the remodeling of leisure fishing row and improving the device for single-fish target strength（TS） measurement in Daya Bay waters,the author measured and studied single-fish target strength of Siganus oramin in South China Sea with Simrad EY60 portable scientific echo sounder（120 kHz） by tethering experimental methods in October 2008,which was video recorded in order to isolate the measurements on single targets.The experiment was set up in natural water and the live fish was held by thin wires.Experimental 16 fish samples of Siganus oramin were all captured by fishing pot in situ in the same area.The fork length of Siganus oramin ranged from 7.3 to 19.5 cm and the average of fork length was 11.3 cm;the weight ranged from 4.6 to 135 g and the average of weight was 33.2 g.The results show that the relationships between TS of pearl-spotted spinefoot（Siganus oramin） and fish fork length are as follows：TS=20lgL-74.1.In this study,the split-beam technology was used for single-fish target strength measurement of different length fish in the South China Sea.The results from this research will facilitate the large-scale studies of single-fish target strength in South China Sea in the future,promote the local applications of fisheries acoustic technology,and improve the accuracy of the survey and evaluation of fishery resources by acoustics in South China Sea.