Fig. 1

Map of wild populations and location of the Matre research station. Wild Atlantic salmon, Salmo salar L., populations originating from six Norwegian rivers were included in the study. Parental salmon were collected directly from the rivers, except for salmon of the River Skibotn and Driva strain that had been conserved and reared in the Norwegian Gene Bank for Atlantic salmon. Parental salmon of the River Vosso strain had been reared by the gene bank until the smolt stage, and then released into the wild. All six wild populations, two domesticated strains and three F1 wild/domesticated strains were produced and reared at the Matre research station. The genome-wide quantitative trait locus (QTL) scan for traits related to freshwater growth were performed on a total of four datasets/experiment, including 134 families and ~ 7000 individuals. The map was produced by using the software QGIS 2.8 (https://www.qgis.org/en)