摘要
日本鳗鲡是亚洲具有重要经济价值的降海洄游鱼类,长江口是我国鳗苗的主产区和仅存的成鳗渔业水域。研究分析了2008年9-11月采自江苏靖江段(31°30′N,120°42′E)的153尾银色鳗样本的年龄和生长参数。结果显示,长江口降海洄游的鳗鲡群体雌性由3～7(平均5.52)龄组成,雄性由3～5(平均4.38)龄组成,雌性群体的年龄结构高且多于雄性群体。雌雄鳗鲡的最大年增长均出现在4龄,但雌性个体的生长拐点年龄ti=5.20、拐点体长lr=683.05mm、拐点体重Wr=546.37g、平均渐近体长L∞=1011.03mm和体重W∞=1830.16g,均显著大于雄性个体的生长拐点年龄ti=4.91、拐点体长lr=517.15mm,拐点体重Wr=216.15g、平均渐近体长L∞=750.30mm和体重W∞=715.90g。研究还表明,长江口降海洄游鳗鲡的群体平均年龄比我国其他地区和日本的均要低,但平均渐近体长却明显要大于其他分布地,预示着长江更适合于鳗鲡的生长和性腺成熟。
Anguilla japonica, is one of the most important commercial catadromous fish species in Asia. Yangtze River estuary serves as the major production regions of larval eels and the only fishery waters of adult eels in China. In this study, we analyzed the age and growth characters for 153 migrating silver eels collected at Jingjiang reach of Jiangsu Province （31°30′N,120°42′E） from Sept. to Nov. 2008. The results showed that the age of the females in Yangtze River estuary ranged from 3 - 7 years with a mean of 5.52 years while the age of males ranged from 3 - 5 years with a mean of 4.38 years. The age structure of female eels is higher and more than male eels. Max. annual gain in length of both female and male A. japonica appeared in the 4th year. The growth parameters of females such as the age of inflexion point, the growth inflexion point of body length, the growth inflexion point of body weight, the average asymptotic body length and the average asymptotic body weight were ti =5. 20, lr =683.05 mm, Wr =546. 37 g, L∞ = 1 011.03 mm and W∞ = 1 830. 16 g, respectively, which were significantly larger than those of males, ti = 4.91, lr = 517. 15 mm, Wr = 216. 15 g, L∞ = 750. 30 mm and W∞ = 715. 90 g. The results indicated that the average age of migrating A. japonica in the Yangtze River Estuary was smaller than those of other regions in China and Japan. However, the average asymptotic body length of migrating A. japonica in the Yangtze River Estuary was significantly larger than those of other regions.
出处
《水产学报》
CAS
CSCD
北大核心
2010年第2期245-254,共10页
Journal of Fisheries of China
基金
国家自然科学基金项目(30771650)
高校博士点基金(20070264001)
上海高校优青项目(SSC-07005)
上海市科委重点项目(08391910200)
上海市教委E-研究院项目(E03009)
上海市重点学科建设项目(J50701)
关键词
日本鳗鲡
银色鳗
矢耳石
年龄组成
生长参数
长江口
Japanese eel
silver eels
sagitta
age structure
growth parameters
the Yangtze River Estuary
