River networks can provide diverse growth and foraging opportunities to mobile consumers. Neighboring glacier-, snow-, and rain-fed streams in proglacial watersheds provide starkly contrasting habitats due to physicochemical differences, giving rise to distinct food webs and resource phenologies. The interplay between seasonal differences in temperature and food availability across stream types yields a shifting landscape of growth opportunities that fish can track by moving between interconnected streams. Fish movement can take place over large spatiotemporal scales during migratory periods and between seasonal refugia, or over small scales when performing daily feeding forays between adjacent habitats. While movement patterns related to behavioral thermoregulation and seasonal migration are well-established in juvenile salmonids, their direct impact on growth requires further research. Our study investigates how movement between a glacial river and two rain-dominated tributaries influences juvenile salmonid growth in a Southeast Alaskan watershed. We collected individual growth histories of PIT-tagged juvenile salmonids using mark-recapture at adjacent glacial mainstem, beaver pond, and rain-driven tributary sites, and we continuously tracked the movement of tagged individuals between the mainstem and tributaries using PIT arrays. Specific growth curves were calculated for each site, and the timing and frequency of fish movement between mainstem and tributary habitats was used to determine whether fish were tracking environmental cues and growth conditions across space. Fish movement patterns varied between individuals and across both seasonal and daily temporal scales. We found distinct differences in seasonal growth rates between glacial rivers and rain-dominated tributary systems, and mobile fish that cycled between adjacent habitats displayed distinct growth trajectories when compared to stationary individuals. These results support the hypothesis that fish can benefit from tracking asynchronies in growth conditions across space and time. Describing fish growth and movement is especially important within proglacial watersheds due to the homogenizing impact of glacial melt across habitat mosaics and associated loss of habitat diversity.