西南大西洋阿根廷滑柔鱼雄性个体的有效繁殖力特性研究

为深入认知阿根廷滑柔鱼 (Illex argentinus) 的繁殖力特性，选取2021年西南大西洋海域的阿根廷滑柔鱼雌性成熟个体样本，利用混合效应模型分析阿根廷滑柔鱼繁殖力特性与栖息海域环境因子之间的关系。结果显示：阿根廷滑柔鱼雌性成熟个体的平均有效繁殖力为 (67 061.72±24 147.00) 粒卵母细胞，成熟卵子最大卵径为1.89 mm、最大能量密度为26.21 kJ·g⁻¹；在不同采样月份，阿根廷滑柔鱼雌性成熟个体的有效繁殖力无显著性差异，而成熟卵子大小及卵子能量密度存在显著的月间差异性；叶绿素a质量浓度是影响有效繁殖力大小的主要环境因子，在质量浓度0.40~0.45 mg·m⁻³时有效繁殖力达到较大值；海表温度、叶绿素a质量浓度和海平面高度3个环境因子均对输卵管卵子大小、卵子能量密度产生显著性影响。研究表明，栖息海域环境因子对阿根廷滑柔鱼个体的繁殖力、卵子大小及卵子能量密度等繁殖力特性具有显著的效应关系，雌性个体的生殖投入分配是对栖息海域环境选择适应的过程。

Growth model identification of short-finned squid Illex argentinus (Cephalopoda: Ommastrephidae) off southern Brazil using statoliths

To obtain a comprehensive understanding of the fecundity characteristics of Argentine shortfin squids (Illex argentinus), we took the mature female individuals of I. argentinus from the southwestern Atlantic Ocean in 2021 as samples, and used a mixed effects model to analyze the relationship between the fecundity characteristics and the environmental factors in their habitat. The results show that the average effective fecundity of mature females was (67 061.72±24 147.00) oocytes, with a maximum egg diameter of 1.89 mm and a peak energy density of 26.21 kJ·g⁻¹. The effective fecundity demonstrated no significant variation across the sampling months, while notable disparities were observed in the oviduct egg size and energy density. The chlorophyll a concentration emerged as a key oceanic determinant influencing the effective fecundity, with the fecundity being comparatively substantial at concentration of 0.40~0.45 mg·m⁻³. Sea surface temperature, chlorophyll a concentration and sea surface height significantly influenced the oviduct egg size and energy density. The research suggests that environmental factors within the marine habitat have a significant influence on the effective fecundity, oviduct egg size and energy density of female I. argentinus. The allocation of reproductive energy by female squids is an adaptive process in response to environmental selection within their habitat.