Cauwelier E, Stewart D C, Millar C P, Gilbey J, Middlemas S J
Marine Scotland Science, Freshwater Fisheries Laboratory, Faskally, Pitlochry, PH16 5LB, U.K.
J Fish Biol. 2018 Mar;92(3):607-620. doi: 10.1111/jfb.13542.
The aim of this study was to examine the genetic structuring, based on c. 4300 single nucleotide polymorphic markers, of juvenile Atlantic salmon Salmo salar sampled from 11 rivers in north-east Scotland, which form part of a radial drainage system. Within this area, sites in the upper mountainous and lower coastal sections of the different rivers were more closely related than sites from the upper and lower sections of the same river. Differentiation between fish from upper and lower sections was related to both distance from the sea and elevation, which were themselves correlated. The occurrence of such cross-river genetic grouping appears to be the result of both similar selective pressures resulting in homologous adaptive differences within each river and also recent common ancestry between rivers. Examination of historical tagging information showed high rates (27·4%) of between-river straying in this region that may help to maintain the across rather than between-river structure. The existence of cross-river groupings highlights the complex structuring of S. salar populations and may confound genetic identification of single-river stocks. Furthermore, the results presented show that cross-river structuring should also be an important consideration in managing S. salar stocks.
本研究的目的是基于约4300个单核苷酸多态性标记，对从苏格兰东北部11条河流采集的幼年大西洋鲑（Salmo salar）的遗传结构进行研究，这些河流构成了一个放射状排水系统的一部分。在该区域内，不同河流上游山区和下游沿海区域的位点比同一条河流上下游区域的位点关系更为密切。上下游鱼类之间的分化与距海距离和海拔高度有关，而这两者本身也是相关的。这种跨河流遗传分组的出现似乎是由于相似的选择压力导致每条河流内出现同源适应性差异，以及河流之间近期存在共同祖先。对历史标记信息的研究表明，该区域河流间的洄游率很高（27.4%），这可能有助于维持跨河流而非河流间的结构。跨河流分组的存在凸显了大西洋鲑种群结构的复杂性，可能会混淆单河流种群的遗传鉴定。此外，给出的结果表明，跨河流结构在大西洋鲑种群管理中也应是一个重要的考虑因素。
