show Abstracthide AbstractLake charr (Salvelinus namaycush) exhibit a great deal of phenotypic and ecological variation between and within lacustrine systems in North America (Chavarie et al., 2021). Studies have shown that many lakes contain different lake charr "forms" that were originally described as morphotypes based on the differences in morphometry that were used to distinguish them (e.g., Bronte and Moore, 2001), and then ecotypes based on the habitats that these forms are found in. The use of the term ecomorph (Baillie et al., 2018) seems to be the best way to describe them since it encompasses both aspects of diversity. The diversity in lake charr ecomorphs has been the subject of many studies looking especially at the relationship of variation to habitat and whether or not variation is a result of hard-wired genetic differences between ecomorphs and/or phenotypic plasticity resulting from environmental influences. This project uses RAD-seq and phenotype data from a nine year experimental study that reared F1 lake trout crosses to identify genetic markers putatively associated with lipid content and condition factor in lean and siscowet lake trout.