social development of free-ranging Atlantic spotted dolphins (Stenella frontalis) in the Bahamas

This study documented the behavioral development of Atlantic spotted dolphins (Stenella frontalis) in the Bahamas. 45 three-minute video-taped sequences of underwater social behavior (aggression, courtship, play), spanning from 1992 to 1996, were selected for ethological analysis and were broken down into 15 adult, 15 juvenile and 15 mixed age class sequences. Continuous focal sub-group sampling was conducted, and one-tailed Kruskal-Wallis ANOVAs were used to test for differences between the age groups in frequencies of occurrence of: (1) the 7 behavioral categories, and (2) the 8 most frequently performed behavioral events. Juveniles performed significantly more Other behaviors and Attention to Object events than adults, suggesting the importance of play within this social species. A Mann-Whitney U test revealed that within mixed age classes, behaviors were performed within combined-age-class groups more often than within single-age-class groups, suggesting a participatory mode of learning within juveniles.