Genomics and telemetry suggest a role for migration harshness in determining overwintering habitat choice, but not gene flow, in anadromous Arctic Char

• DOI: 10.1111/mec.14393
• Publication Date: 2017-10-31T09:26:36Z
• Authors: Jean‐Sébastien Moore; Les N. Harris; Jérémy Le Luyer; Ben J.G. Sutherland; Quentin Rougemont; Ross F. Tallman; Aaron T. Fisk; Louis Bernatchez
• Keywords: Arctic char; Overwintering

Migration is a ubiquitous life history trait with profound evolutionary and ecological consequences. Recent developments in telemetry genomics, when combined, can bring significant insights on the migratory ecology of nonmodel organisms wild. Here, we used this integrative approach to document dispersal, gene flow potential for local adaptation anadromous Arctic Char from six rivers Canadian Arctic. Acoustic data 124 tracked individuals indicated asymmetric large proportion fish (72%) tagged three different migrating up same short river fall. Population genomics 6,136 SNP markers revealed weak, albeit significant, population differentiation (average pairwise FST = 0.011) dispersal was also by assignments. Approximate Bayesian computation simulations suggested presence flow, although opposite direction that observed data, suggesting does not necessarily lead flow. These observations home their natal spawn, but may overwinter shortest route minimize costs migration nonbreeding years. Genome scans genetic-environment associations identified 90 outlier putatively under selection, 23 which were or near gene. Of these, at least four involved muscle cardiac function, consistent hypothesis harshness could drive adaptation. Our study illustrates power integrating migrations logistically challenging environments such as