长江干流圆筒吻(鱼句)的年龄与生长

根据551尾标本研究了生活在长江干流中圆筒吻(鱼句)的年龄与生长,并提出了资源合理利用建议.圆筒吻(鱼句)的鳞片可作为年龄鉴定的依据,年轮形成期主要在2～5月.圆筒吻(鱼句)的体长与鳞长呈直线关系,与体重呈幂指数关系,生长适合Von Bertalanffy生长方程.在1～2龄生长最快,为保护圆筒吻(鱼句)资源,应限捕体长200 mm以下的个体.

Age and Growth of Rhinogobio cylindricus in the Mainstream of Yangtze River

Age and growth of Rhinogobio cylindricus were studied based on 551 specimens collected from mainstream of Yangtze River, and rational utilization of the species is proposed. Data of the scales of R.cylindricus were used to determine the age and to calculate the body length of the fish at various ages. It was found that the new annuli began to appear from February to May. The relationship between body length and scale radius is linear, and the relationship between body length and body weight is exponential. The growth of R.cylindricus corresponds with Von Bertalanffy growth equation. The fish grows faster before the age of two. For the purpose of resource conservation, fishing of individuals up to 200 mm should be controlled.