UC Davis

Animal behavior is the primary source of information that zoo professionals use to infer animals’ psychological state and welfare. Chapter 1 is a general introduction for the dissertation and a background on the topics covered. In Chapter 2, I introduce a statistical analysis approach to evaluate general behavioral theories by observing individuals of many species, called Species-Independent Combined-Individual Mixed-Model Analysis (SICIMMA). This chapter guides on the importance of zoo researchers testing general behaviors at the individual level as they house hundreds of different species and many behavior theories are general, not species-specific. I applied this approach to assess if the presence of the primary keeper impacts the behavior of 15 individuals (Chapter 3). I hypothesized that animals behave differently in the keepers’ presence than in the keeper’s absence because caretakers are associated with primary reinforcers. Overall, I observed animals being more active in their keepers’ presence than when the keeper was not present. We demonstrated that keeper presence is an environmental context in which animals behave differently than in keeper absence. In Chapter 4, I applied the statistical approach SICIMMA to investigate how two different categories of environmental enrichment influence the behavior and welfare indicators of 8 individuals. I hypothesized that compared to manipulable objects, problem-solving opportunities would result in more activity and exploration throughout the day and would have greater impact on anticipatory behavior that occurs at the end of the day prior to a reliable reward. I observed that puzzle feeders decrease anticipatory and anxiety-like behavior and increase social behavior more than object enrichment. Overall, this research offers guidance on testing general behavioral concepts on multi-species individuals and demonstrates the influence of two zoo environmental contexts on animal behavior and welfare indicators.