Abstract Fish stocking is one of the most widespread and frequent management strategies in freshwater systems. However, the contribution of stocked fish to the population is seldom investigated, and hence the effectiveness of this strategy is virtually unknown for many populations. Understanding the contribution of stocked fish into the population is crucial because it allows the disentanglement of the confounding effects generated by allochthonous individuals into the estimation of survival and growth rates of the population. To discriminate between the allochthonous and autochthonous individuals in a population, the shape of sagittae otoliths from pikeperch (Sander lucioperca) where compared. Results indicated significant differences among stocked and non-stocked fish, with the former having smaller and wider sagittae otoliths than the latter. Our results suggest that this technique can be used to discriminate the natal origin of fish in a much faster and cheaper way than commonly used techniques.

中文翻译：

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人工饲养和本土梭鲈（Sander lucioperca）之间的耳石形状变化

摘要 鱼类放养是淡水系统中最普遍和最常见的管理策略之一。然而，很少研究放养鱼类对种群的贡献，因此对于许多种群来说，这种策略的有效性实际上是未知的。了解放养的鱼类对种群的贡献至关重要，因为它可以将异地个体产生的混杂影响分解为种群存活率和增长率的估计。为了区分种群中的外来个体和本土个体，比较了梭鲈（Sander lucioperca）的矢状耳石的形状。结果表明放养和未放养的鱼之间存在显着差异，前者比后者具有更小和更宽的矢状耳石。