2.1 Sample Collection
Natural-origin steelhead were collected from populations of both the
inland and coastal lineages across multipe years from 1996 to 2018 and
exhibit a range of migration timing. Samples were collected with a
variety of methods, such as electrofishing, smolt traps, and weirs.
Non-lethal fin tissue samples and biologically relevant metrics were
collected from both smolts and returning adults. Steelhead were
collected from locations distributed throughout the Columbia River
basin. Sample sizes and coordinates for each collection provided in
Figure 1 and Appendix S1 in Table S1.