Work

Anthropogenic effects on activity patterns and vigilance in Cape chacma baboons (Papio ursinus ursinus) in the Garden Route, South Africa

Year: 2026

Type: article

Abstract: Anthropogenic activities shape animals’ time allocation and risk perception, yet their immediate behavioural impacts on primate species remain poorly quantified. In this study, variation in activity budgets and vigilance was analysed in three Cape chacma baboon ( Papio ursinus ursinus ) troops inhabiting contrasting anthropogenic environments in South Africa’s Garden Route: Madiba (high disturbance), North (intermediate disturbance), and Outeniqua (low disturbance). From March to June 2024, a total of 84 h of observations were recorded yielding 343 scan samples, and behaviour was modelled as a function of troop and environmental covariates (weather, habitat openness, car and human presence). Feeding dominated overall time allocation (35.4%), with no whole-budget differences among troops, but behaviour-specific contrasts emerged. The Outeniqua troop relied less on human-derived foods and showed lower running frequencies than troops in more anthropogenic environments. High intensity vigilance (active/intense scanning) was also elevated in Madiba and North troops compared to Outeniqua, although this pattern was sensitive to dataset composition and should be interpreted with caution. Environmental models revealed that anthropogenic disturbance primarily affected vigilance behaviour, while associations with feeding, locomotion, and affiliative behaviours were weaker and more context dependent. These responses were further modulated by habitat openness and weather conditions. Overall, these results indicate that anthropogenic disturbance affects primate behaviour through fine-scale adjustments rather than broad changes in activity budgets, highlighting context-dependent trade-offs between foraging, vigilance, and social interactions. These findings provide insights into how primates respond to human-modified environments and inform the management of human–wildlife interactions.

Source: Global Ecology and Conservation

DOI: 10.1016/j.gecco.2026.e04310