利用耳石日轮研究珠江口棘头梅童鱼的产卵期及生长

测记耳石生长轮纹数量,依据耳石日轮对采自珠江口的棘头梅童鱼(Collichthys lucidus)的日龄进行了鉴定、并据此研究了其产卵期和生长特性.棘头梅童鱼的产卵期为12月至次年的7月,主要集中在2、4、5月,产卵高峰出现在5月,占样本总数的27.27%;其次为2月,占18.18%.用直线、幂函数和指数函数关系对棘头梅童鱼的生长特性进行回归分析,体长范围为29.8～104.0 mm的棘头梅童鱼的体长与体重关系为幂函数关系,体重生长为匀速生长;体长随日龄的生长关系以幂函数模型符合程度较好,体重与日龄的生长关系则符合指数关系和幂函数关系.研究结果表明,利用耳石日龄来推算棘头梅童鱼的产卵期是可行的,并可用于研究一定体长范围内鱼的生长.

Studies on the spawning period and growth of Collichthys lucidus in estuary of Pearl River based on otolith daily annulus

In order to understand the propagation and spawning of Collichthys lucidus in the estuary of Pearl River, from January to December 2006,43 specimens in body length of 29.8 - 104.0ram were taken in the inlet of Humen sea,Guangdong Province. Spawning period and growth characteristics of C. lucidus was investigated with otolith age determination. Spawning period of the species occurred from December to July the next year, particularly in Februar- y,April and May,with the peak season in May（27.27% ） and in February（ 18.18% ）. The growth characteristics were analyzed with linear, power and exponential correlations, respectively. In the lengths mentioned, power correlation was found between body length and body weight and the body weight was in a pattern of regular growth. Power correlation was fitted for the growth of body length against daily age, while power and exponential functions were fitted for the growth of body weight against daily age. The results showed that spawning season estimation and growth measurement of C. lucidus were workable with otolith age determination for fish in range from 29.8 to 104.0 mm.