UC San Diego

Synchrony is a well-established behavior that is frequently seen in cetaceans where surfacing events serve as a commonly used marker to spot synchrony due to its visibility from land. However, underwater behavior prior to and followed by synchronous surfacing is limited despite dolphins spending most of their time underwater. Therefore, we report an examination of the relationship between synchronous surfacing and an underwater swimming behavior ‘partnered swimming’ (parallel swimming of dolphins in close-proximity for an extended period of time) based on an observational study of 7 Bottlenose dolphins (Tursiops truncatus) kept under human care in Brookfield Zoo, Chicago. Results demonstrated that synchronous surfacing serves as a reliable predictor of partnered swimming both before and after the surfacing events and further suggest that subjects’ preferential associate for the two indices are positively correlated during synchronous swimming in close proximity and aligned orientation. Further results on triadic analysis suggest that proximity in partnered swimming indicates a higher frequency of close-proximity synchronous surfacing between the two that are in closer proximity than the third animal. These results are consistent with previous research on synchrony and proximity and suggest that proximity can indicate the level of synchrony, as evidenced by shorter latency periods between closer-proximal synchronous surfacing events. These findings contribute to our understanding of the social dynamics and affiliative behavior of bottlenose dolphins as surfacing is a social marker to provide a peak in the understanding of a more complex underwater behavior.