Analysis of a Rough-Toothed Dolphin (Steno bredanensis) Introduction in a Human Care Setting

Rough-toothed dolphins are a rarely studied species of cetaceans found in temperate and tropical waters throughout the world. These dolphins live in fission-fusion societies and are highly social, swimming in tightly-packed and highly synchronized subgroups consisting of 2-10 individuals. The current study documents the introduction of a stranded calf into an existing population of six rough-toothed dolphins living in a human care setting. Specifically, recordings of vocal and non-vocal behaviors were analyzed across the four phases of the study: baseline, day of introduction, post-introduction, and follow-up. Whistles, a vocal signal associated with social contexts, increased from baseline to post-introduction phases (after an initial drop on the day of introduction) for both the new dolphin and the resident group. Non-vocal social behaviors showed the same pattern. Finally, whistle production was associated with social behaviors when considering all of the phases, but the association only held for the baseline condition when the relationship was assessed within each phase. This research helps to build knowledge about how this little-known species navigates the formation of new relationships and may inform procedures for future dolphin introductions