长湖短颌鲚的年龄与生长特性

2014年采集自湖北长湖的479尾短颌鲚(Coilia brachygnathus)样本,研究了长湖种群的年龄结构和生长特性。短颌鲚的耳石和鳞片均可用于鉴定短颌鲚年龄,且两者鉴定年龄的吻合度达到75.8%。长湖短颌鲚种群的年龄组成为1~4龄,其中1~3龄鱼为主,占总样本量的96.0%。短颌鲚属匀速生长型,其体重和体长的关系为:W=6.290×10-6L2.855(n=479,R2=0.959,P0.01),且无明显性别差异。长湖短颌鲚体长与体重的生长符合Von Bertalanffy生长方程:L_t=332.8691-e-0.213(t+1.775)],W_t=99.9401-e-0.213(t+1.775)]2.855,其生长拐点为t=3.15龄。为了可持续开发利用长湖短颌鲚渔业资源,建议捕捞规格提高到体长200 mm。

Study on the age and growth characteristics of Coilia brachygnathus in lake Changhu

A total of 479 individuals of Coilia brachygnathus were collected from Lake Changhu, Hubei Province, in 2014, to reveal the age and growth characteristics. Both otoliths and scales of C. brachygnathus could be used to identify its age, and their matching degree reached 75. 8%. There were 4 age classes ranging 1 to 4 in the population, with pre-ponderant age classes of 1 ~3 years old, which accounted for 96. 0% of the total population; The relationship between body weight and body length was described by the equation: W=6.290 ×10 -6L2.855(n=479, R2 =0.959, P<0.01), and significant difference was not found between both sexes in the length-weight relation. The Von Bertalanffy growth func-tion was Lt =332. 869 1-e-0.213(t+1. 775)], Wt =99. 940 1 -e-0.213(t+1. 775)]2.855, and the growth inflexion point of the body weight was 3. 15 years. In order to sustainably utilize the C. brachygnathus population, we suggest that the individuals larger that 200 mm could be harvested.