基于耳石微结构的黄、渤海蓝点马鲛幼鱼日龄与生长

鱼类的生长是影响群体资源量的要素,研究鱼类的生长规律是开展资源评估工作的基础。本研究依据2016年9-10月和2017年8-10月在黄渤海采集的当年生蓝点马鲛(Scomberomorus niphonius)幼鱼,通过耳石微结构分析,确定了蓝点马鲛孵化期,建立了生长模型并估算了生长率。结果显示,幼鱼日龄范围为64~151 d,孵化日期为5月3日至6月15日,高峰期集中在5月20日至6月3日。叉长和体质量的生长符合Logistic生长模型。叉长平均绝对生长率和特定生长率分别为2.45 mm/d和0.85%/d,生长率随着日龄增大而小幅度减小。体质量平均绝对生长率和特定生长率分别为5.33 g/d和2.68%/d,最大绝对生长率和最大特定生长率分别出现在111~120 d和91~100 d。本研究表明,蓝点马鲛幼鱼生长随日龄发生变化,早期生长较以往进一步加快。

Daily age and growth of young-of-the-year Scomberomorus niphonius in the Yellow Sea and Bohai Sea based on otolith microstructure

The growth of fish is an important factor affecting the stock biomass. Studying the pattern of fish growth underpins fish stock assessment. This study was conducted based on otolith microstructure analysis of young-of-the-year (YOY) Scomberomorus niphonius collected from September to October in 2016 and August to October in 2017 from the Yellow Sea and Bohai Sea. The hatching dates were determined for each individual. The growth models were established and the growth rates were calculated. The results showed that the age range of YOY S. niphonius was 64–151 d. The hatching dates fell between 3 May and 15 June, with a peak between 20 May and 3 June. The Logistic model gave the best fit to growth of fork length and body weight. The average absolute growth rate and specific growth rate of the fork length were 2.45 mm/d and 0.85 %/d, respectively. The growth rate decreased slightly with the increase of age. The average absolute growth rate and specific growth rate of body weight were 5.33 g/d and 2.68%/d, respectively. The maximum absolute growth rate and maximum specific growth rate occurred at 111–120 d and 91–100 d, respectively. The results of this study showed that the growth of YOY S. niphonius varied with age, and the early growth of the S. niphonius accelerated further than before.