Once exploited for fur, meat, and extracting the yellowish exudate called castoreum, the Eurasian beaver disappeared from Romania during the eighteenth century. After, the reintroductions carried out two decades ago are currently thriving in the Danube River basin. Using nine nSSR markers, we analysed samples from 98 individuals, and we found no genetic substructure, suggesting high dispersal and gene flow capabilities. The stepwise mutation model (SMM) indicated the existence of a recent genetic bottleneck, though the Eurasian beaver retains high levels of genetic diversity and population growth facilitated variation in nSSR loci. A fine-scale spatial correlation in females was detected, contrasting with males’ dispersal on longer distances. While the movement and establishment of individuals’ new territories were made under natural predation pressure, the mix following natural expansion improved the fitness and could contribute to a higher genetic diversity than the source population. With any reintroduction, a focus on capturing individuals from various geographic origins, as well as securing many and suitable founding individuals (adults, subadults, and juveniles) with mixed origins, could secure the post-genetic bottleneck recovery and higher genetic diversity. Beyond this conservation success, future management strategies should consider building a National Action Plan (NAP) for the species, including a permanent genetic monitoring programme for Eurasian beaver.

欧亚海狸曾被用于毛皮、肉类和提取称为海狸香的黄色渗出物，在 18 世纪从罗马尼亚消失了。此后，二十年前进行的重新引入目前在多瑙河流域蓬勃发展。我们使用九个 nSSR 标记分析了来自 98 个个体的样本，我们没有发现遗传亚结构，这表明具有高分散和基因流动能力。逐步突变模型 (SMM) 表明存在最近的遗传瓶颈，尽管欧亚海狸保留了高水平的遗传多样性和种群增长促进了 nSSR 基因座的变异。检测到女性的精细空间相关性，与男性在更远距离上的分散形成鲜明对比。虽然个体新领土的移动和建立是在自然捕食压力下进行的，但自然扩张后的混合改善了适应性，并可能有助于比源种群更高的遗传多样性。通过任何重新引入，专注于捕获来自不同地理起源的个体，以及确保具有混合起源的许多合适的创始个体（成体、亚成体和幼体），可以确保后遗传瓶颈恢复和更高的遗传多样性。除了这一保护成功之外，未来的管理战略还应考虑为该物种制定国家行动计划 (NAP)，包括一项针对欧亚海狸的永久性遗传监测计划。自然扩张后的混合改善了适应性，并可能有助于比源种群更高的遗传多样性。通过任何重新引入，专注于捕获来自不同地理起源的个体，以及确保具有混合起源的许多合适的创始个体（成体、亚成体和幼体），可以确保后遗传瓶颈恢复和更高的遗传多样性。除了这一保护成功之外，未来的管理战略还应考虑为该物种制定国家行动计划 (NAP)，包括一项针对欧亚海狸的永久性遗传监测计划。自然扩张后的混合改善了适应性，并可能有助于比源种群更高的遗传多样性。通过任何重新引入，专注于捕获来自不同地理起源的个体，以及确保具有混合起源的许多合适的创始个体（成体、亚成体和幼体），可以确保后遗传瓶颈恢复和更高的遗传多样性。除了这一保护成功之外，未来的管理战略还应考虑为该物种制定国家行动计划 (NAP)，包括一项针对欧亚海狸的永久性遗传监测计划。可以确保后遗传瓶颈恢复和更高的遗传多样性。除了这一保护成功之外，未来的管理战略还应考虑为该物种制定国家行动计划 (NAP)，包括一项针对欧亚海狸的永久性遗传监测计划。可以确保后遗传瓶颈恢复和更高的遗传多样性。除了这一保护成功之外，未来的管理战略还应考虑为该物种制定国家行动计划 (NAP)，包括一项针对欧亚海狸的永久性遗传监测计划。