biostudies-literatureUnknown122(36)Cayuela HEach year, billions of animals migrate across the globe on diverse spatial and temporal scales. Migration behavior thus plays a fundamental role in the life cycle and Darwinian fitness of many organisms. While the influence of migration on early-life survival and reproduction is well documented, its effects on senescence (aging) in advanced age remain largely unexplored. Using a unique 44-y ring-resighting dataset from a long-lived, partially migratory bird species, the Greater Flamingo (<i>Phoenicopterus roseus</i>), we demonstrate that migration plays a key role in shaping age-specific trajectories of mortality and reproduction. Resident flamingos exhibit higher early-life demographic performances, with lower baseline mortality than migrants, resulting in longer adult lifespan. ResidentsProceedings of the National Academy of Sciences of the United States of Americae2422882122https://www.ebi.ac.uk/biostudies/studies/S-EPMC12440607biostudies-literatureMigration shapes senescence in a long-lived bird.PMC12440607Germain CArnaud AChampagnon JBechet ARoques SCayuela HfalseMigration shapes senescence in a long-lived bird.Each year, billions of animals migrate across the globe on diverse spatial and temporal scales. Migration behavior thus plays a fundamental role in the life cycle and Darwinian fitness of many organisms. While the influence of migration on early-life survival and reproduction is well documented, its effects on senescence (aging) in advanced age remain largely unexplored. Using a unique 44-y ring-resighting dataset from a long-lived, partially migratory bird species, the Greater Flamingo (<i>Phoenicopterus roseus</i>), we demonstrate that migration plays a key role in shaping age-specific trajectories of mortality and reproduction. Resident flamingos exhibit higher early-life demographic performances, with lower baseline mortality than migrants, resulting in longer adult lifespan. Residents2025-01-01T00:00:00Z2025 Sep2026-07-09T12:26:22.798Z2026-07-09T11:17:54.039ZS-EPMC124406074085411010.1073/pnas.2422882122