基于耳石微结构的南海春季鸢乌贼日龄、生长与种群结构的研究

摘要

The current study investigated the purple back flying squid (Sthenoteuthis oualaniensis) collected by light at-tracting falling-net fishing vessels in the spring of 2015 in the South China Sea. The mantle lengths ofS. oualaniensis were ranged from 10.22 to 199.01 mm while the body mass were ranged from 1.3 to 328.8 g. The Age, growth and popu-lation structures ofS. oualaniensis were studied based on the microstructure of statolith. The result showed that there were two groups ofS. oualaniensis in the South China Sea: the medium-sized (with photophore on the dorsal mantle) and dwarf groups (without photophore on the dorsal mantle) accounting for 59.38% and 40.62%, respectively, and that there was no large group whose mantle lengths were more than 500 mm. The ages of the sample were ranged from 38 to 126d among which the dominant age was from 51 to 80d, accounting for 81.33%. According to the AIC values of these five growth models in different waters and groups, the exponential growth model appropriately reflect the growth ofS. oualaniensis in northern South China Sea and Nansha adjacent waters; the exponential growth model suitably ex-plain the middle-size group and the power function growth model was best for dwarf groups. Moreover, the individual growth rate of squid in the northern South China Sea was slightly slower than that in Nansha adjacent waters. The growth rate of the dwarf groups first increased rapidly and then gradually decreased while the medium-sized groups were totally on the contrary.%2015年春季在南海开展灯光罩网渔船鸢乌贼(Sthenoteuthis oualaniensis)采样,样品胴长为10.22-199.01 mm,体质量为1.3-328.8 g.研究根据鸢乌贼耳石微结构对其日龄、生长和种群结构进行研究,结果显示:南海存在2个鸢乌贼群体,中型群体(有发光器,占59.38%)和微型群体(无发光器,占40.62%),无胴长大于500 mm的大型群体;样品日龄范围为38-126d,优势日龄组为51-80d,占其总数的81.33%.分别计算不同海域和群体间5种生长模型的AIC权重值,发现南海北部海域和南沙附近海域都以指数生长模型最适合描述鸢乌贼的生长关系,中型群体以指数模型最为适合,微型群体则以幂函数生长模型最适合;南海北部海域的鸢乌贼个体生长速率略低于南沙附近海域鸢乌贼个体;微型群体呈现急剧生长到逐渐缓慢生长的趋势,中型群体的生长趋势与微型群体正好相反.同类相食现象表明微型群体的生长受到中型群体的影响而被抑制.