摩洛哥南部沿岸沙丁鱼生物学特性的初步研究

根据2011年6-8月中国资源探捕渔船在摩洛哥专属经济区海域（21°00′～ 26°00′N、15°30′～20°00′W）采集的沙丁鱼Sardina pilchardus样本,对其生物学进行初步分析.结果表明：渔获物的雌雄性比为0.93∶1,叉长小于170 mm和大于230mm的样本中雌雄性比均较大,分别为2.67∶1和3.3∶1,其余叉长范围的雌雄性比为（0.66～1.12）∶1;雌性个体的叉长范围为150 ～270mm,优势叉长为190 ～230mm,占雌性总数的81.51％,雄性个体的叉长范围为150 ～ 250 mm,优势叉长为190 ～230mm,占雄性总数的84.47％;雌性个体的体质量范围为60 ～210 g,优势体质量为90～ 150 g,占雌性总数的85.46％,雄性个体的体质量范围为60 ～210 g,优势体质量为90～ 150 g,占雄性总数的93.44％;沙丁鱼体质量与叉长的关系方程为W雌性=7×10-6L3.1076（R2=0.8483,P＜0.001）,W雄性=9×10-6L3.0653（R2 =0.8140,P＜0.001）;雌性个体中未成熟个体、成熟个体、繁殖后个体分别占76.47％、19.64％、3.89％,雄性个体中未成熟个体、成熟个体、繁殖后个体分别占69.04％、30.08％、0.88％;经拟合,半数雌性个体达初次性成熟时的叉长为228.14 mm,半数雄性个体达初次性成熟时的叉长为219.78 mm;对所取样本进行摄食情况分析,发现胃级为0级和1级的样本最多且所占比例相近,但未出现胃数为4级的样本.     

Fish hosts of the freshwater mussel Unio foucauldianus Pallary, 1936

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