Wealth from Oceans Flagship, CSIRO Marine and Atmospheric Research, GPO Box 1538, Hobart, 7001 Tasmania, Australia.
J Fish Biol. 2013 May;82(5):1523-44. doi: 10.1111/jfb.12077.
Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark-recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks.
基于对来自西南太平洋大部分地区的黄鳍金枪鱼（Thunnus alalunga）耳石横切面上每年形成的不透明白色生长带的计数，提出了经过验证的年龄估计值。使用每日生长轮的计数来估算第一枚不透明白色生长带的位置，该位置在第一个假定的生日之前就已形成。通过边际增量分析和土霉素标记重捕实验来估算不透明白色带的周期性。这两种验证方法均表明，不透明白色带是在南半球夏季形成的，并在秋季到冬季（4 月至 8 月）完成。对来自同一鱼的耳石和背鳍刺上的年龄估计值进行直接比较表明存在偏差，这被认为是由于刺上的早期生长带的增量清晰度差和吸收，导致年龄估计不准确。因此，与背鳍刺相比，耳石的年龄估计被认为更准确。这与越来越多的热带和温带金枪鱼属（Thunnini）物种的结果一致。建议使用经过验证的耳石切片上每年生长带的计数作为评估和管理建议这些重要种群的基于年龄参数的首选方法。
