Otolith daily increments in the Japanese eel.
Otolith daily increments in the Japanese eel.
复制标题
日本鳗鱼的耳石每日增量。
DOI：
10.2331/suisan.55.1017
复制
发表时间：
1989
影响因子：
0.4
通讯作者：
K. Tsukamoto
中科院分区：
文献类型：
--
作者：
K. Tsukamoto
许多鱼类的耳石中发现了细小的增量或同心环。1，2）耳石中的这些微结构已被用作许多研究的年龄特征，这些研究带有明确的假设，即耳石增量是每天形成的。建立耳石年龄测定方法应满足以下三个条件：（1）确定增量的沉积速率;（2）了解第一个增量形成的时间;（3）估计增量计数中与年龄相关的偏差。在不满足上述三个条件的情况下，年龄测定的数据有时会导致我们得出错误的结果或结论。在日本鳗鲡的耳石中也发现了类似于日生长量的微结构。3.4）然而，这些微结构的完整验证尚未完成。Umezawa等（5）在人工受精并饲养6天的鳗鱼幼体中发现了围绕箭形肌核心的同心环的日沉积。然而，早期阶段不到一周的观察仍不足以全面验证该物种，我们不能仅从这些数据得出结论，耳石日环沉积在leptocephalus和幼鱼阶段以及刚孵化的幼虫阶段。因此，本研究探讨日本鳗鲡幼鱼耳石生长的周期性，以建立日本鳗鲡幼鱼年龄的判定方法。
Fine increments or concentric rings are found in otoliths of many fish species.1,2) These micro structure in otoliths have been applied as an age character to many studies carrying the explicit assumption that the otolith increments were formed daily.1) However, a full-scale validation of otolith microstructure must be a necessary prerequisite to otolith work of any kind. In order to establish the method of age determination with otolith, the following three conditions should be filled: (1) to determine the deposition rate of the increments, (2) to know the timing of the first in crement formation, and (3) to estimate the age associated bias in the increment count. Data from the age determination without fulfillment of the above three conditions sometimes lead us to a misdirected result or conclusion. In the Japanese eel, microstructure like daily increment was also reported in the otolith.3.4) However, complete validation of these micro structure has not been finished, yet. Umezawa et at.5) found the daily deposition of the concentric rings around the core of sagitta in the larvae of eel which was artificially fertilized and reared for 6 days after hatching. However, the observation for less than one week at an early stage is still in sufficient for the full-scale validation of this species, and we can not conclude only from these data that the eel deposits otolith daily rings during lepto cephalus and elver stages as well as larval stage just after hatching. Consequently, the periodicity of otolith increment in the Japanese eel elver was examined in this study in order to establish the age determination method of this species.