Accurate and consistent age readings are cornerstones of age‐based assessment and management of exploited fish stocks. Otoliths are the preferred structure for age determination, often performed by counting the number of completed 001 zones. Uncertainty regarding the identification of the first translucent zone and the timing of translucent zone formation can cause skewed age determination even in species with otherwise clearly defined annuli. This study addresses an inter‐institutional discrepancy in age readings of the East Greenland Atlantic cod Gadus morhua L. By analysing the opacity of the otolith margin of cod sampled monthly from February to December, it was shown that translucent zones are formed primarily during March–May. Size distributions of the dorsal–ventral and proximal–distal widths of the first three translucent zones are provided as guide to their identification. This study provides new knowledge that resolves the discrepancy in age reading of East Greenland Atlantic cod.

中文翻译：

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通过确定耳石生长区的时间和环宽度来提高东格陵兰大西洋鳕鱼（加德斯·摩尔瓦）的年龄读数

准确，一致的年龄读数是基于年龄的剥削鱼类种群评估和管理的基石。耳石是确定年龄的首选结构，通常通过对已完成的001个区域进行计数来完成。关于第一个半透明区域的标识以及半透明区域形成时间的不确定性，即使在具有明确定义的环的物种中，也可能导致年龄的确定偏差。这项研究解决了东格陵兰大西洋鳕鱼Gadus morhua年龄读数的机构间差异L.通过分析从2月到12月每月采样的鳕鱼耳石耳缘的不透明度，可以看出半透明区域主要形成于3月至5月。前三个半透明区域的背-腹和近-远端宽度的大小分布提供了对其进行识别的指南。这项研究提供了解决东格陵兰大西洋鳕鱼年龄差异的新知识。