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Description: ABSTRACT -- Understanding the basic life history patterns of highly migratory species is important for effective management. For sea turtles, evidence of developmental biogeography and discrete life stage residency provides key information for understanding resource use and population threats and defining conservation priorities. Resolving these knowledge gaps is not straightforward, however. Inaccessible habitats, low survivorship, late maturity ages, and technology limitations all complicate monitoring individuals continuously throughout their life span. Here we expand on previous studies and document a near-complete tissue record in the ultimate posterior marginal scutes of hawksbill sea turtle (Eretmochelys imbricata) carapace. While stable isotope analysis (SIA) of ventral scute surfaces reveals differences between 3 geographically isolated populations in the Pacific and Atlantic basins, sequential sampling along growth line contours of sectioned scutes reveals developmental migrations. Perhaps surprisingly, no clear or general patterns emerge. Bivariate isoscape data (δ13C, δ15N) indicate only 1 of 6 Central Pacific hawksbills showed a distinct ontogenetic shift. And while all 3 Western Pacific individuals showed evidence of ontogenetic shifts, these individuals had 3 unique patterns. We summarize stable isotope values for foraging items of Pacific hawksbills, discuss the drivers of regional variability and trophic downgrading, and make recommendations for future study.