西北太平洋公海加利福尼亚标灯鱼年龄和生长

Age and growth of Symbolphorus californensis in the high sea of Northwest Pacific Ocean

摘要:

为探究加利福尼亚标灯鱼（Symbolphorus californensis）的基础生物学信息,本研究根据2022年6—7月在西北太平洋公海海域采集的175尾样本,通过耳石微结构的观察,对其年龄和生长进行研究分析。结果表明,加利福尼亚标灯鱼的矢耳石呈卵圆形,背缘有波状浅沟,听沟明显,纵截面微观结构显示出3个生长区：中心区（CZ）、中间区（MZ）和外部区（EZ）,轮纹数分别为41~62、38~45和157~465；根据生长纹计数,计算日龄为242~550 d,优势日龄组为301~400 d,占91.46%；根据捕获时间推算样本孵化时间约为2021年3—8月,其中高峰孵化日期约为2021年5—6月；赤池信息准则分析显示,最适生长方程为贝塔朗菲模型（von Bertalanffy）： L_t=146.325×｛1-exp[-0.01×（t-229.392）]｝；此外,研究还表明加利福尼亚标灯鱼的生长纹具有明显的月球周期性,即在满月期间具有更窄的生长纹宽度。研究结果揭示了加利福尼亚标灯鱼的生活史特征,为日后资源利用提供科学依据。

关键词:加利福尼亚标灯鱼;耳石;年龄与生长;月相;西北太平洋

Abstract:

To understand the fishery biology of Symbolphorus californensis, the age and growth were analyzed in 175 samples collected in the high seas of Northwest Pacific Ocean from June to July 2022 through the observation of otolith microstructure. The results showed that the sagittal otolith of S. californensis is elliptical, with a sinuate dorsal margin, shallow sulcus, and rounded to oval cauda. The otolith microstructure along sagittal section exhibited three of the growth zones： CZ, MZ and EZ, respectively with 45-50、38-45 and 157-465 daily growth increments. The sum of daily growth increments in the three zones determined an age range （lifespan） of S. californensis specimens as 242-550 days, with the dominant group from 301 days to 400 days （91.46%）. By obtaining the age in days of each specimen, the back-calculated hatching date of specimens collected was determined as from March to August of last year with a peak in May to June. The AIC analysis indicates that the optimal growth equation is the von Bertalanffy growth model, with the fitting as： L_t=146.325×｛1-exp[-0.01×（t-229.392）]｝.In addition, S. californensis of Northwest Pacific Ocean was found to have daily growth increments of its sagittal otolith, which also exhibited lunar periodicity in the deposition of increments, with growth increments during the full moon period. The results of this study reveal its life history characteristics and provide scientific basis for future resource utilization.

Key words:Symbolphorus californensis;statolith;age and growth;lunar periodicity;Northwest Pacific Ocean