Bubble Stream Production by Belugas (Delphinapterus leucas)

• Main Author: Slack, Megan
• Format: Text
• Language: unknown
• Published: Digital USD 2018
• Subjects: beluga; bubble; mammal; whale; vocalization; behavior; Animal Studies; Behavior and Ethology; Biological Psychology; Biology; Biostatistics; Categorical Data Analysis; Cognition and Perception; Environmental Sciences; Environmental Studies; Experimental Analysis of Behavior; Interpersonal and Small Group Communication; Marine Biology; Oceanography; Personality and Social Contexts; Terrestrial and Aquatic Ecology; Zoology; Beluga; Beluga*; Delphinapterus leucas
• Online Access: https://digital.sandiego.edu/theses/29; https://digital.sandiego.edu/cgi/viewcontent.cgi?article=1029&context=theses

Bubble stream production in belugas has been poorly characterized and its function is not well understood. I examined behavioral states when producing bubble streams (“bubbling”), and when bubbling calls, to determine whether bubbling was significantly associated with a particular call category or behavioral state. Using 19 hours of video and audio recordings collected over a two-day period, I quantified bubble streams of a 4-month old calf and an unrelated adult female housed together. Based on the overall activity budgets and pool of vocalizations for both animals, I calculated the expected counts of bubble streams with and without vocalizations, assuming that they occurred randomly (χ2 Goodness of Fit, p < 0.001). I also compared rates of behavior in time blocks (95% CI). The calf produced 419 bubble streams, and the adult female produced 98. Bubble streams were significantly more likely than expected during social-affiliative interactions, but when the whales were not in close contact. The calf vocalized with 20% of bubble streams (86 vocalizations) and the adult female with 18% (18 vocalizations). The animals produced vocalizations with only a small proportion (3.3%) of their bubble streams. Synchronous bubbling was highly correlated to call type in the case of the adult female – she only produced bubbles with one call type. No significant relationship between bubble usage and call type was found for the calf. Overall, the results were most consistent with the hypothesis that bubble streams serve as a visual cue during social-affiliative interactions between belugas.