Reproductive Stage Influences Residency and Site Fidelity in Female Common Bottlenose Dolphins From the Coastal Waters Off the Southwestern Gulf of Mexico

ABSTRACT Movements and behavior of cetaceans are shaped by their habitat, but reproductive physiology can further influence residency and spatial use, especially in gestating and calf‐rearing females. We analyzed a long‐term photo‐ID dataset to assess differences in residency and behavior among the reproductive stages (gestation, dependent calf, and interbreeding interval) of adult female bottlenose dolphins, in the heavily fished waters off Alvarado, Veracruz. From 143 surveys, we identified over 400 individuals, from which 142 were sexed (122 females and 20 males) across five periods, spanning 2002–2023. Reproductive stages were reliably assigned to 11.5% of females (representing 27% of the local core community). Individual residency and site fidelity metrics grouped females in three main clusters (i.e., regular residents, occasional residents, and occasional visitors). Females in gestation were rarely recorded and spent half of this stage outside our study area, whereas dependent calf and interbreeding interval were more common. Calf‐rearing females showed higher residency and site fidelity, but their weaning period was within the lower range for the species ( = 2.6 years), suggesting possible behavioral adjustments to local human‐induced stressors such as fishing pressure and vessel traffic. In contrast, males showed significantly higher residency indices across most metrics and periods, highlighting strong sex‐based differences in spatial ecology. Behavioral budgets confirmed that this region remains an important feeding ground for both sexes and a nursing habitat for females, despite well‐known fisheries‐related threats. Notably, a sharp increase in the proportion of occasional visitor females over the end of the study, suggests a potential population‐level shift. Our findings highlight the critical role of reproductive status in shaping fine‐scale movement ecology of bottlenose dolphins and the importance of long‐term monitoring in human‐impacted ecosystems.