Characterizing curiosity-related behavior in bottlenose (Tursiops truncatus) and rough-toothed (Steno bredanensis) dolphins

Dolphins are frequently described as curious animals; however, there have been few systematic investigations of how dolphins behave when they are curious and the extent to which individual differences in curiosity exist in dolphins. Previous research has described individual differences in dolphins’ frequency of interactions with environmental enrichment as well as quantifying curiosity-related traits of dolphins via personality assessments, though behavioral observation and trait rating components have not been part of the same study. The present study describes two different experiments designed to elicit curiosity in 15 bottlenose ( Tursiops truncatus ) and 6 rough-toothed ( Steno bredanensis ) dolphins. In Experiment 1, dolphins displayed more curiosity-related behavior toward a stimulus with spontaneous movement (jack-in-the box) compared to their reaction to a static control object; however, in Experiment 2, the subjects did not conform to hypotheses, and displayed few behavioral differences when shown expectation-violating stimuli compared to a control stimulus. The results of this study supported the hypothesis that there would be a wide range of individual differences in dolphins’ reactions to the stimuli, including differences between species and sex, as well as differences in trait ratings by trainers. These findings provide information that may be useful for future research aimed at assessing curiosity in dolphins, as well as for making environmental enrichment decisions for dolphins in human care