Tourism encounters with macaques: A comparative analysis of human–wildlife interactions in Gibraltar

Human-wildlife interactions, particularly in tourism-dominated environments, significantly impact primate behaviour, yet how these pressures vary across different ecological settings remain relatively understudied. This study aimed to investigate the influence of tourist presence on Barbary macaque, Macaca sylvanus Linnaeus, 1758 (Primates Cercopithecidae) behaviour at two distinct sites within the Upper Rock Nature Reserve (URNR) in Gibraltar: Prince Phillip’s Arch (PPA) and St Michael’s Cave (SMC). The research enhanced our understanding on how factors such as habitat structure and varying tourist pressures shape macaque activity patterns, social interactions, and stress-related behaviours. Through behavioural observations, we recorded macaque state behaviours (grooming, foraging, vigilance, etc.) and interactions (agonistic, anthropogenic, etc.) across both sites over a 6-month period. A comparison between the two sites revealed that PPA, characterised by confined spaces and high tourist traffic, had significantly higher grooming and vigilance behaviours, while macaques at SMC exhibited more foraging and movement, likely due to more open terrain and dispersed tourist presence. Self-directed behaviours, indicators of stress, were notably higher at PPA. Anthropogenic interactions, including feeding by visitors, were common at both sites but more frequent at SMC. The findings suggest that tourist density and site-specific habitat structures significantly influence macaque behaviour, with PPA macaques showing higher stress and aggression levels due to spatial limitations and visitor proximity. These results highlight the importance of implementing site-specific management strategies, including regulating tourist access, enforcing no-feeding policies, and enhancing habitat design, to mitigate stress on wildlife.