Using otolith weight to predict the age of Pennahia macrocephalus in the mouth of the Beibu Gulf  

作　　者：颜云榕 吴艳芳 卢伙胜 李忠炉 金显仕 

机构地区：[1]Faculty of Fisheries,Guangdong Ocean University [2]Institute of Oceanology,Chinese Academy of Sciences [3]Graduate School of Chinese Academy of Sciences [4]Yellow Sea Fisheries Research Institute,Chinese Academy of Fisheries Sciences

出　　处：《Chinese Journal of Oceanology and Limnology》2009年第2期342-349,共8页中国海洋湖沼学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China (No. 30771653);Bureau of Fisheries, Ministry of Agriculture

摘　　要：The relation between otolith weight (OW) and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the South China Sea, in 2007. Since there are no significant differences in sagittal OW between otolith in pairs (P≥0.05), the undamaged left sagittal otolith is used for age determination. The highest correlations among standard length, OW and fish ages are confirmed by linear, exponential and multinomial regression. Results show that sagittal OW overlaps only occasionally among age groups, and to individuals with similar standard length, the older and slower-growing fish has a heavier otolith because of the continued otolith material deposition. There are differences in sagittal OW among different age groups and significant positive linear relationship with age (P<0.05). The age readings can be verified by plotting the sagittal OW versus the standard length for age groups, and the individuals with similar standard length but in different ages can be separated by sagittal OW frequency analysis. Mostly, the predicted ages using the regression between sagittal OW and ages are closed to the observed ages by counting annulus on scale. It indicates that the sagittal OW analysis is a useful technique for validating the accuracy of age determination by annuli counts, especially for individuals of similar size. Furthermore, the technique is applied for Pennahia macrocephalus with discussion in this paper.The relation between otolith weight （OW） and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the South China Sea, in 2007. Since there are no significant differences in sagittal OW between otolith in pairs （P≥0.05）, the undamaged left sagittal otolith is used for age determination. The highest correlations among standard length, OW and fish ages are confirmed by linear, exponential and multinomial regression. Results show that sagittal OW overlaps only occasionally among age groups, and to individuals with similar standard length, the older and slower-growing fish has a heavier otolith because of the continued otolith material deposition. There are differences in sagittal OW among different age groups and significant positive linear relationship with age （P〈0.05）. The age readings can be verified by plotting the sagittal OW versus the standard length for age groups, and the individuals with similar standard length but in different ages can be separated by sagittal OW frequency analysis. Mostly, the predicted ages using the regression between sagittal OW and ages are closed to the observed ages by counting annulus on scale. It indicates that the sagittal OW analysis is a useful technique for validating the accuracy of age determination by annuli counts, especially for individuals of similar size. Furthermore, the technique is applied for Pennahia macrocephalus with discussion in this paper.

关 键 词：Pennahia macrocephalus sagittal otolith weight-age relationship the mouth of the BeibuGulf 

分 类 号：S917.4[农业科学—水产科学]