珠江口棘头梅童鱼耳石的生长特性

研究了棘头梅童鱼(Collichthys lucidus)耳石的形态参数、生长特性及其与鱼体生长的关系,选用左矢耳石为研究对象,用直线、对数、多项式、幂函数和指数函数拟合矢耳石各参数的生长关系式,依据耳石日轮鉴定了日龄。结果表明,体长范围为29.8～104.0 mm的棘头梅童鱼矢耳石的长直径随鱼体生长而增大,但短直径与长直径的比值以及长直径方向上的短半径与长半径的比值则基本稳定。矢耳石的长、宽和重之间,以及长半径和短半径之间均呈显著的幂函数相关关系;矢耳石生长与鱼体生长的关系中,矢耳石长、宽、厚、重与长半径和体长、体重之间的关系,除了体长与耳石厚的关系为显著的二次多项式外,全部呈显著的幂函数相关关系。

Otolith Growth Characteristics of Collichthys lucidus from the Pearl River Estuary

Morphological parameters and otolith growth of Collichthys lucidus were investigated by counting and measuring the daily rings in the left sagitta. Linear, logarithmic, polynomial, functional and exponential growth equations were used to describe the growth of otolith by morphological parameters of sagitta and to determinate daily age by the daily ring of sagittae. The long diameter of otolith in C.lucidus grew longer as fish body length increase within the range of 29.8-104.0 mm, but the ratio of short diameter /long diameter and short radius/long radius was rather stable. A significant power functional relationship was found out between long, width and weight of sagitta and between long radius and short radius. The relationships between length, width, thickness and weight of sagitta with fish body length and weight showed a significant power relationship except for the parameter of fish body length and thickness of sagitta which was represented by quadratic polynomial function equation.