鳙目标强度和行为特征的水声学研究

In situ hydroacoustic estimates of the target strength and behavior characteristics of Aristichthys nobilis

使用EY60回声探测仪于2010年5月10—15日、9月28—29日分别对5种不同体长规格的鳙进行了目标强度及昼夜行为的现场测定。结果显示:鳙的全长范围为30.05～80.00 cm,体长范围为25.10～68.80 cm,体重范围为0.3～6.0 kg,对应的有效目标强度范围为-51.84～-42.06 dB,最大目标强度范围为-47.53～-37.06 dB。鳙的目标强度(TS)与其全长、体长、体重的对数值(logBL、logTL、logW)线性回归关系均显著(P<0.01);平均有效目标强度回归方程标准误为0.55～0.61 dB,较最大目标强度回归方程更为准确。另外,鳙的平均游动速度为0.15 m/s,且有明显的昼夜垂直移动规律。

In order to accurately evaluate the target strength（TS） and behavior characteristics of Aristichthys nobilis,day-night acoustic measurement on 5 different lengths of A.nobilis was carried out on May 10 to 15 and September 28 to 29,2010,using the Simrad EY60 split-beam echo-sounder.Results showed that the total length,the body length and weight range of A.nobilis were 30.05 cm to 80.00 cm,25.1cm to 68.80 cm and 0.3 kg to 6.0 kg respectively,and the corresponding range of average target strength was-51.84 to-42.06 dB,the correspongding range of maximum target strength was-47.53 to-37.06 dB.The target strength of A.nobilis and the logarithm of the fish size（length or weight） was in linear correlation,linear models between TS and the logarithm of the fish size were fitted with length or weight well for predicting TS,and the linear regression relations were significant（P〈0.01,P〈0.01 and P〈0.01 respectively）.Typically,the standard error of estimate was 0.55 to 0.61 dB for the regression equations of average target strength,so which was more accurate than the maximum target strength′s.Obvious day-night vertical movement of A.nobilis was detected and the average swimming speed was 0.15 m/s.