The present study established an age determination technique and analyzed growth patterns in three sculpins, Myoxocephalus jaok, Enophrys diceraus, and Gymnocanthus herzensteini, which are major components of demersal fish assemblages in the subarctic Pacific. In all three species, only two or three otolith opaque zones were detected by surface observations, but numerous opaque zones were observed on otolith thin sections. For all species, the results of the study suggest that otolith opaque zones were formed annually. Although opaque zones were probably formed during summer for M. jaok and G. herzensteini, the timing could not be clarified for E. diceraus. The standard lengths at the same ages were greatest in M. jaok, moderate in G. herzensteini, and smallest in E. diceraus. In M. jaok and G. herzensteini, Bertalanffy growth curves were estimated for each sex, and were found to differ significantly between sexes. The bycatch of M. jaok and G. herzensteini in the western coastal Pacific around Hokkaido consisted mainly of young individuals, while that of E. diceraus was primarily older individuals. The results of this study may facilitate an understanding of the biological characteristics of sculpins not only around Hokkaido, but throughout the subarctic Pacific.

中文翻译：

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日本北海道岛周围西太平洋海域三种海洋杜柱鱼 Myoxocephalus jaokEnophrys diceraus 和 Gymnocanthus herzensteini 的年龄和生长以及渔业兼捕杜柱鱼的年龄组成

本研究建立了一种年龄测定技术，并分析了三种杜鹃（Myoxocephalus jaok、Enophrys diceraus 和 Gymnocanthus herzensteini）的生长模式，它们是亚北极太平洋底栖鱼类组合的主要成分。在所有三个物种中，通过表面观察仅检测到两个或三个耳石不透明区域，但在耳石薄片上观察到许多不透明区域。对于所有物种，研究结果表明耳石不透明区每年都会形成。尽管 M. jaok 和 G. herzensteini 可能在夏季形成不透明区，但 E. diceraus 的时间无法确定。相同年龄的标准长度在 M. jaok 中最大，在 G. herzensteini 中适中，在 E. diceraus 中最小。在 M. jaok 和 G. herzensteini 中，Bertalanffy 生长曲线对每个性别进行估计，发现性别之间存在显着差异。M. jaok 和 G. herzensteini 在北海道周围西太平洋沿岸的副渔获物主要由年轻个体组成，而 E. diceraus 则主要由年长个体组成。这项研究的结果可能有助于了解不仅在北海道周围而且在整个亚北极太平洋地区的杜鹃花的生物学特征。