Food provisioning and agonistic behaviours in commensal long-tailed macaque (Macaca fascicularis) at Uluwatu Temple, Bali (Indonesia)

Abstract

Most previous research on nonhuman primates reported increased levels of agonistic behaviors associated with food provisioning by humans. To further investigate the permanence of this effect of increased social competition in long-term commensal-living primates, we examined the immediate impact of food provisioning on agonistic behavior rates in a commensal population of long-tailed macaques (Macaca fascicularis) at Uluwatu Temple, Bali (Indonesia). We compared proportions of agonistic behaviors between various food provisioning levels defined by the absence/presence and the quantity of food provisioned. We collected data using focal and scan sampling methods during a four-month study period (June to October 2010). We performed non-parametric statistical tests (Wilcoxon Test & Friedman Test; p < .05) on a population sample of 66 individuals. Results did not show obvious impact of provisioning on agonism rates, nor increase of potential appeasement strategies such as sexual behaviours, grooming or self-directed behaviours, often associated with the presence of provisioned food. These data suggest that the long-tailed macaques at Uluwatu Temple are responding effectively to high provisioning level, that is, without increasing social competition. We hypothesize that the high spatiotemporal abundance of human food, associated with the species’ eco-behavioural flexibility and the long term story of human-macaque commensal relationships in Uluwatu may explain the absence of provisioning impact on agonistic rates