Growth Studies on North Sea Herring II. 0-Group Growth of East Anglian Herring
Growth Studies on North Sea Herring II. 0-Group Growth of East Anglian Herring
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北海鲱鱼的生长研究 II。
DOI：
10.1093/icesjms/32.1.98
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发表时间：
1968
影响因子：
3.3
通讯作者：
T. Iles
中科院分区：
文献类型：
--
作者：
T. Iles
对连续样本之间的变化进行分析，即每年在季节性东盎格鲁渔业中重新出现一个年份等级，此外还可以对补充程度进行估计，从而对第一年的增长进行精确的比较估计。当比较相同年份的生长情况时，0 组生长的显着变化和波动不一定与 I 组（和更老的）鱼的情况相似；必须假定，这反映了近海幼体阶段和生活史后续阶段之间栖息地偏好、行为和生态的不连续性。20 世纪 40 年代初，当未捕捞的成体种群大量增加时，0 群体生长显着下降，表明密度依赖因素正在发挥作用。这一假设得到了有关幼虫丰度和审查期间后半段西鲱年级相对丰度的数据的一些定量支持，并暗示密度依赖性是 0 群生长的一个不可或缺的特征。由于密度依赖性和环境因素的影响分离的问题，这样的假设很难证明，但是生长速度和幼鱼的存活率之间的联系可以在密度依赖性关系中产生。
The analysis of the variation inl1estimates between successive samples, that is as a year-class re-appears each year in the seasonal East Anglian fishery, besides making possible the estimation of the degree of recruitment results in precise comparative estimates of first-year growth. The marked changes and fluctuations in 0-group growth do not necessarily parallel those found for I-group (and older) fish when the same years of growth are compared; it must be assumed that this reflects the discontinuity which occurs in habitat preference, behaviour and ecology between the inshore juvenile stages and the subsequent phases of the life history.A significant decline in 0-group growth during the early 1940s, when the unfished adult stock increased in abundance, suggests that density-dependent factors were operating. This hypothesis receives some quantitative support from data on larval abundance and on the relative abundance of sprat year-classes over the latter part of the period under review, and implies that density dependence is an integral feature of 0-group growth. A hypothesis such as this is difficult to prove because of the problem of separating the effects of density dependence and of environmental factors, but a link between growth rate and survival of very young fish could be generated in a density-dependent relationship.