Abstract
Among the zoological industry, unmanaged social aggression may lead to decreased animal welfare, as well as negatively affect guest programs and staff safety. In order to manage aggression, baseline data are needed to better understand antecedent conditions and anomalous trends. Tooth rake marks were used to objectively compare the relative rates of intraspecific aggression among a managed care population of Atlantic bottlenose dolphins (Tursiops truncatus). Weekly rake make frequencies were documented from 2013 to 2014 and compared between sexes and among age classes. Statistical process control was utilized to detect amomalous increases in aggression and retrospectively identify relationships between high levels of aggression and distinct animal and operational events. Rake mark frequency was significantly higher in males versus females, and calves and juveniles exhibited significantly more rake marks than adults, which may reflect age-ordered social hierarchies. Retrospective analyses indicated an increase in rake mark frequencies that coincided with the introduction of new members to the population. Thus, social aggression is not randomly distributed over time and is likely to be strongly influenced by animal management operations.