Connectivity of Common Bottlenose Dolphin Habitats Between the Kuroshio Current and Its Adjacent Waters, as Evidenced by Extended‐Term Satellite Tracking

ABSTRACT The common bottlenose dolphin (CBD) inhabits the waters surrounding the Kuroshio Current in the western North Pacific. Understanding its population structure is critical for effective conservation and management. However, the tracking durations of fin‐mounted Advanced Research and Global Observation Satellite tags in a previous study were limited to 48 days, restricting insights. This study aimed to improve the understanding of the habitat range of CBDs by extended tracking periods. Between 2020 and 2024, tags were deployed on 14 CBDs off Kii Peninsula facing the Kuroshio waters. Tagged dolphins were tracked for up to 103 days. Most dolphins remained in the coastal waters along the Kuroshio Current, while some moved into the East China Sea or along the Southwest Islands. The movement patterns showed flexibility, with CBDs shifting directions, likely influenced by oceanographic conditions, such as water currents. State‐space models fitted with the tracking data showed that the Kuroshio coastal waters were the primary habitat for CBDs. The study also found that some dolphins migrated across the Kuroshio Current to other areas. These results highlight the dynamic nature of CBD habitat use and the importance of long‐term tracking to fully understand their migration and population structure for successful conservation efforts.