Geraldes Armando, Askelson Kenneth K, Nikelski Ellen, Doyle Frank I, Harrower William L, Winker Kevin, Irwin Darren E
Biodiversity Research Centre University of British Columbia Vancouver British Columbia Canada.
Department of Zoology University of British Columbia Vancouver British Columbia Canada.
Evol Appl. 2019 Jan 12;12(4):757-772. doi: 10.1111/eva.12754. eCollection 2019 Apr.
Accurate knowledge of geographic ranges and genetic relationships among populations is important when managing a species or population of conservation concern. Along the western coast of Canada, a subspecies of the northern goshawk () is legally designated as Threatened. The range and distinctness of this form, in comparison with the broadly distributed North American subspecies (), is unclear. Given this morphological uncertainty, we analyzed genomic relationships in thousands of single nucleotide polymorphisms identified using genotyping-by-sequencing of high-quality genetic samples. Results revealed a genetically distinct population of northern goshawks on the archipelago of Haida Gwaii and subtle structuring among other North American sampling regions. We then developed genotyping assays for ten loci that are highly differentiated between the two main genetic clusters, allowing inclusion of hundreds of low-quality samples and confirming that the distinct genetic cluster is restricted to Haida Gwaii. As the form was originally described as being based on Haida Gwaii (where the type specimen is from), further morphological analysis may result in this name being restricted to the Haida Gwaii genetic cluster. Regardless of taxonomic treatment, the distinct Haida Gwaii genetic cluster along with the small and declining population size of the Haida Gwaii population suggests a high risk of extinction of an ecologically and genetically distinct form of northern goshawk. Outside of Haida Gwaii, sampling regions along the coast of BC and southeast Alaska (often considered regions inhabited by ) show some subtle differentiation from other North American regions. These results will increase the effectiveness of conservation management of northern goshawks in northwestern North America. More broadly, other conservation-related studies of genetic variation may benefit from the two-step approach we employed that first surveys genomic variation using high-quality samples and then genotypes low-quality samples at particularly informative loci.
在管理受保护的物种或种群时，准确了解种群的地理分布范围和遗传关系非常重要。在加拿大西海岸，北方苍鹰的一个亚种被依法指定为濒危物种。与分布广泛的北美亚种相比，这种形态的分布范围和独特性尚不清楚。鉴于这种形态上的不确定性，我们对通过对高质量基因样本进行测序基因分型鉴定出的数千个单核苷酸多态性的基因组关系进行了分析。结果显示，在海达瓜伊群岛上存在一个基因独特的北方苍鹰种群，并且在北美其他采样区域之间存在细微的结构差异。然后，我们针对在两个主要基因簇之间高度分化的十个位点开发了基因分型检测方法，从而能够纳入数百个低质量样本，并证实这个独特的基因簇仅限于海达瓜伊群岛。由于最初描述的[该形态名称]是基于海达瓜伊群岛（模式标本来自此地），进一步的形态分析可能会导致这个名称仅限于海达瓜伊群岛的基因簇。无论分类处理如何，海达瓜伊群岛独特的基因簇以及海达瓜伊群岛种群数量少且不断下降的情况表明，北方苍鹰这种在生态和基因上都独特的形态面临着很高的灭绝风险。在海达瓜伊群岛之外，不列颠哥伦比亚省海岸和阿拉斯加东南部的采样区域（通常被认为是[另一亚种名称]栖息的区域）与北美其他区域表现出一些细微的差异。这些结果将提高北美西北部北方苍鹰保护管理的有效性。更广泛地说，其他与保护相关的遗传变异研究可能会从我们采用的两步法中受益，该方法首先使用高质量样本调查基因组变异，然后在特别有信息价值的位点对低质量样本进行基因分型。
