Date of Award

Fall 12-1-2017

Degree Type


Degree Name

Doctor of Philosophy (PhD)



Committee Chair

Donald Sacco

Committee Chair Department


Committee Member 2

Lauren Highfill

Committee Member 2 Department


Committee Member 3

Richard S. Mohn

Committee Member 3 Department

Educational Research and Administration

Committee Member 4

Alen Hajnal

Committee Member 4 Department



Bubble production through exhalation is unique to marine mammals due to the combination of their air-breathing physiology and aquatic environment. Multiple types of bubble production are reported in the literature, including bubble netting, trails, bursts, and rings. Unfortunately, apart from bubbles produced to facilitate hunting or play, current understanding of the function of bubble production in cetaceans is limited to anecdotal accounts and author interpretations. This study aims to identify the function of three bubble types though observations of behaviors present before, during, and after bubble production. Instances of bubble trails, bubble bursts, and scant bubbles were selected from underwater video observation of bottlenose dolphins in human care. Rates of behaviors before, during, and after bubble production were recorded for each individual present during a bubble event, along with the individual’s age, sex, and role as bubbler or bystander. Suites of observed behaviors were grouped by function for analyses. Logistic regressions were used to determine which behavioral factors and demographics predicted bubble production across time periods for different bubble types. Predicting behaviors for bubble trail production showed use in multiple social situations. Behaviors predicting bubble burst production indicated use in avoidance, sexual behavior, object engagement, and as early exhalation during surfacing. Scant bubble production predictive behaviors demonstrated use in close proximity social behavior and non-social interest. These results provide a better understanding of how bubble production types fit into the behavioral repertoire, which supports some previously suggested behavioral uses of bubble production, and provides future research on bubble production directions to explore. By identifying these differences in behavioral patterns, we can better identify the function of bubble behaviors and how they fit into the bottlenose dolphin behavioral repertoire. Ultimately, this will enable us to better interpret bubble behaviors, benefiting future experimental and observational studies interested in behavioral responses of bottlenose dolphins.