摘要
本文根据带鱼耳石横断面切片的显微观测和鱼体测量结果,着重分析物种数量分布中心海区的主体种群和不同季节出生群的生长特征,并对种群生长的地理差异以及年代差异与渔业资源的合理利用问题进行了探讨。
The purpose of the present report is to study the population growth of a highly commercially exploited species,Hairtails,in its major distribution area in order to provide a ibasis for controlling the population dynamics and considering possible management measures.The specimens of the main population used for this study were collected in the northern East China Sea from May 1977 to June 1978,but some elder ones were the spaw-ners in 1976 and 1979,and specimens of other populations were collected from 9 fishing grounds located in the South China Sea and the southern East China Sea as well as the Bohai Sea and Huangbai Sea in.recent years.Based on the study of the age,the measurement of the body and its otolith transverse section,the relative growth of otolith and population growth pattern as well as the weight-length relationship of this fish,the problem of geographical differences in population growth ih the northern Bast China Sea and elsewhere is discussed.The results of our study are summarized as follows:1.The otolith and(body growth of this fish are’closely related to the form of the power function curve,so that the otoliih can be used for(back-calculating the fish growth.2.The females fish grows slightly faster than the males,but the growth differences between the sexes are not significant statistically.3.Based on the bimodal distribution of first ring radius of otolith and body length of young fish,it may be concluded that the Hairtails generally consist of two or three groups such as spring and summer and autumn broods,but so far as concerns the main population,it may be devided into two groups by the size of the first ring radius,the earlier-born group.(spring and summer broed,r>0.72 mm)and late-born group au tumn brood,r<0.72mm).4.The weight-length relationships of the main population(A+S)and its earlierborn group(S)and later-born group(A)are expressed in equations 19-21.5.The growth pattern of this fish could be expressed in equations 13-24.6.Growth in weight with age for this fish is determined also as a typically asby-metric sigmoid curve,the inflexion corresponding to maximum growth rate occurs at 3.26 age(3.17 for ealier-born group and 3.43 for later-born group).It has been observed that the majority of individuals in 1 age group has attained sexual maturity and all the males and females’become sexually mature in 2 years.The significance of the infle-xion of the population growth equation by weight should be further netted because the size at instantaneous first capture providing the maximum yield generally lies at around this point.7.The increment and incremental rate of this fish in standard length and weight are described with dL/dt,d^(2)L/dt^(2),dW/dt and d^(2)W/dt^(2)curves respectively(F g.2,4).8.The obvious growth difference in body length and weight between the earlier and later-born group is found only in first two years,but not so obvious in growon parameters such as the limiting body length,weight and inflexion of growth curve for weight.9.The geographical difference in population growth is found obvious orey between the populations of sub-tropical waters(the South China Sea)and temperate waters.10.The Hairtails have a more rapid growth rate than the Large Yelloy Croaker or the Small Yellow Croaker,and its long breeding period as well as the predt tory and mixed feeding habit account for its great productivity.While the number of the other two species of croakers are greatly reduced as a result of heavy fishing pressure.,they are still present in significant amount to be the main fish stock of the fishing ground and their growth rate is get higher than years ago.If the fishing of the,last two lowest age,group can be postponed one or two years later,its population productivity may possibly be increased greatly.Thus,it is very promosing to have a further development of this fishery..
作者
吴鹤洲
成贵书
周建魁
王建飞
Wu Hezhou;Cheng Guishu;Zhou Jiankui;Wang Jianfei(Institute of Oceanology,Academia Sinica,Qingdao)
出处
《海洋与湖沼》
1985年第2期156-168,共13页
Oceanologia Et Limnologia Sinica
