Baker, K. C., Ruhde, A. 2018. Macroenvironmental effects on the well-being of singly-caged male rhesus macaques (Macaca mulatta). American Journal of Primatology 80(S1), 47 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #146).

Determining the effects of the macroenvironment on the welfare of nonhuman primates can help identify their needs and guide their behavioral management. We evaluated the behavior of 37 adult male rhesus macaques in two housing settings at the Tulane National Primate Research Center. While caging and enrichment were identical, the two settings varied in the level of disruption in the macroenvironment. Individuals housed in the high‐disruption location were exposed to more frequent potentially stressful human activity and as well as visual and auditory exposure to a larger and more rapidly shifting population of animals. Behavioral data (240 h) were collected using instantaneous focal animal sampling. Multivariate analysis of variance was used to test the effects of condition, with temperament and age as covariates. Only main effects of condition were found. Individuals in the high‐disruption condition showed lower levels of observer‐directed aggression (p=.008), a trend toward less anxiety‐related behavior (p=.078), and higher levels of vigilance (p=.012). Levels of abnormal behavior, alarm calling, and aggressive displays did not vary. These findings do not support the notion that frequent potentially stressful activity and low levels of stability inevitably result in chronic stress. Furthermore, the lack of correspondence between patterns of vigilance and indicators of reduced well‐being suggest an unclear relationship between focused environmental scanning and anxiety, fear, and distress.