Data from: A genetic assessment of the human-facilitated colonization history of black swans in Australia and New Zealand

Movement of species beyond their indigenous distribution can fundamentally alter the conservation status of the populations involved. If introductions are human-facilitated, introduced species could be considered pests. Characterizing the colonization history of introduced species can, therefore, be critical to formulating the objectives and nature of wildlife management strategies. The black swan (Cygnus atratus) is native to Australia but is considered a reintroduced species in New Zealand, where the endemic population was reported extinct during the 19th century. After the re-introduction of a small number of individuals from Australia, the New Zealand population expanded unexpectedly rapidly, which was attributed to simultaneous waves of migration from Australia. An alternative, but hitherto unformalized, hypothesis is that local extant populations remained and admixed with introduced individuals. To contribute to our understanding of the reintroduction history of the species, we investigated dispersal patterns and demographic histories of seven populations from Australia and New Zealand, using population genetic inferences from a microsatellite dataset. Our results on genetic structure, dispersal rates, and demographic histories provide mixed evidence on the origin of New Zealand black swans. The hypothesis that reintroduced individuals mixed with remaining local individuals and that the subsequent dramatic population expansion may have been due to genetic rescue of the inbred indigenous population cannot be discarded and needs further investigation.

物种突破本土分布范围的迁移，可从根本上改变所涉种群的保护现状。若物种引入由人类活动介导，则该引入种（introduced species）可被视为有害生物。因此，阐明引入种的定殖历史，对制定野生动物管理策略的目标与核心原则至关重要。
黑天鹅（Cygnus atratus）原产于澳大利亚，但在新西兰被视作再引入种（reintroduced species）——19世纪时已有报道称新西兰的特有黑天鹅种群已灭绝。在从澳大利亚引入少量个体后，新西兰黑天鹅种群的扩张速度远超预期，该现象被归因于来自澳大利亚的同步迁移浪潮。另有一个迄今尚未被正式验证的假说认为，当地现存种群得以留存，并与引入个体发生了基因混合。
为加深对该物种再引入历史的认知，本研究借助微卫星数据集（microsatellite dataset）开展种群遗传学推断（population genetic inferences），对澳大利亚与新西兰的7个黑天鹅种群的扩散模式与种群历史动态展开了调查。
本研究关于遗传结构、扩散速率及种群历史动态的结果，为新西兰黑天鹅的起源提供了相互矛盾的证据。再引入个体与留存本土个体发生融合，且后续种群的急剧扩张或源于对近交本土种群的遗传拯救（genetic rescue）——这一假说仍无法被排除，尚需进一步研究验证。