1. Differential migration timing between sex or age classes are examples of how migratory movement strategies can differ among sub-groups within a population. However, in songbirds, evidence for intrinsic differences in en route migratory behavior is often mixed, suggesting that the local environmental context may play a role in accentuating or diminishing patterns. 2. We evaluated how multiple intrinsic and extrinsic variables influenced refueling rates, local movement behavior, and departure decisions in the White-throated Sparrow (Zonotrichia albicollis) during spring migration. This species exhibits a unique genetically-based plumage dimorphism, providing a unique class of individual in which to evaluate patterns and processes of differential migration, in addition to sex, age, and migration distance. 3. At a migratory stopover site, plasma metabolite analysis was used to quantify individual variation in stopover refueling rate. In after second year adults, automated and manual radio telemetry was used to quantify daily activity timing, daily movement distances, stopover duration, and departure time. Arrival timing to the stopover site was determined using capture data. Non-breeding and previous breeding/natal latitude were determined using analysis of hydrogen isotopes in claws and feathers. 4. Males arrived at the stopover site 11 days on average before females, but no difference in migration timing was observed between plumage morph or age classes. After second year adults with more southern previous breeding latitudes arrived at stopover earlier whereas second year birds making their first return migration arrived at stopover in an inverse relationship to non-breeding latitude. Stopover refueling rate did not differ between ages, sexes, or plumage morphs, and daily departure probability of adults was higher under warmer temperatures and favorable tailwinds. White-striped morphs moved greater distances during stopover, initiated daily activity earlier in the morning, and departed for migration earlier in the evening than tan-striped morphs. 5. Our results show that while individual phenotype can influence some aspects of local stopover-scale movement behavior, evidence for differential stopover behavior was weak. Differential migration timing is unlikely to result from intrinsic differences in en route refueling rate and departure decisions, especially because the latter is strongly influenced by meteorological conditions. 

Complete data was not collected for every bird processed during the spring of 2017. As such, there are missing values in the WTSP dataset. Missing values in the manual telemetry dataset are primarily associated with the time of release at the release point.