Fig. 1.

Samples locations. Samples for epigenetic (methylation profiling) and population genomics analyses are shown in blue: CAP, Capilano River (n = 20), QUI, Quinsam River (n = 19). Samples for whole-genome resequencing (n = 20) are shown in red. CAP, Capilano (n = 5); INC, Inch Creek (n = 5); ROB, Robertson River (n = 5); SAL, Salmon River (n = 5). Resequencing samples were obtained from a hatchery located downstream of each river of origin, except Salmon River, for which the river of origin is represented while the fish were reared at Spius Creek hatchery, Meritt (British Columbia, BC, Canada).