Abstract Inconnu (Stenodus leucichthys) is a large freshwater migratory coregonid species that is commercially fished in some parts of its range. In Great Slave Lake, NT, Inconnu are one species that is caught in a mixed species gillnet fishery that is subject to restrictive management because four of the seven known stocks are declining or have been extirpated. The seven known Inconnu stocks have been identified based on the river systems that support or once supported a spawning population. To help identify key geographic areas for harvest control and other management approaches, we estimated the genetic diversity and population genetic structure of Inconnu in this area with 17 microsatellite loci. Temporal and spatial genetic structure was examined in four river systems, lower and upper Mackenzie River, Buffalo River, Slave River and Marian River/Lake and within Great Slave Lake. Analyses suggested that genetic diversity was greater in lower/upper Mackenzie River populations compared to populations in Great Slave Lake. Genetic structure was temporally stable at all locations except one, and spatial structure was found with significant isolation by distance detected among locations. Bayesian clustering analysis suggested five genetic groups of Inconnu, one in the lower and upper Mackenzie River and four within Great Slave Lake. The substructuring within Great Slave Lake included a genetic group representing fish collected in the lake itself. In addition, three genetic groups corresponded to river systems (Buffalo River, Marian River/Lake, Slave River), indicating that each river has genetically distinct Inconnu populations. These results suggest that the sustainability of Inconnu in and around Great Slave Lake depends upon maintaining stocks associated with river systems, especially those that are geographically disparate.

中文翻译：

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加拿大西北地区大奴湖 Inconnu (Stenodus leucichthys) 的遗传评估

摘要 Inconnu (Stenodus leucichthys) 是一种大型的淡水洄游鸬鹚物种，在其分布范围的某些部分进行商业捕捞。在北领地的大奴湖，因科努是一种在混种刺网渔业中捕获的物种，由于七种已知种群中有四种正在减少或已灭绝，因此受到限制性管理。已根据支持或曾经支持产卵种群的河流系统确定了七种已知的因科努种群。为了帮助确定收获控制和其他管理方法的关键地理区域，我们通过 17 个微卫星位点估计了该地区 Inconnu 的遗传多样性和种群遗传结构。在四个河流系统中检查了时空遗传结构，麦肯齐河上游和下游，布法罗河，奴隶河和玛丽安河/湖以及大奴隶湖内。分析表明，与大奴湖种群相比，麦肯齐河下游/上游种群的遗传多样性更大。除一处外，所有位置的遗传结构在时间上都是稳定的，并且通过检测位置之间的距离发现空间结构具有显着的隔离性。贝叶斯聚类分析表明 Inconnu 有 5 个遗传群，1 个在 Mackenzie 河下游和上游，4 个在大奴隶湖。Great Slave Lake 内的子结构包括一个代表在湖中收集的鱼类的遗传组。此外，三个遗传组对应于河流系统（布法罗河、玛丽安河/湖、奴隶河），表明每条河流都有不同的遗传种群。