Patterns of sleeping site use of Guinea baboon parties (Papio papio)

Sleeping site use in primates is thought to be influenced by multiple factors, including resource availability and competition, predation risk, and the risk of parasitic infection. While previous research has highlighted the importance of these factors, few studies have examined sleeping site use among multiple groups of non-territorial species with overlapping home ranges. Here, we investigated the sleeping site use of Guinea baboons (Papio papio) in Simenti, Senegal. We used locational data for four years of several baboon parties sharing the same range. We assessed the distribution of sleeping sites within the local habitat mosaic, the proximity of sleeping sites to those of co-occurring parties and the impact of food availability and predator presence at the landscape level on the distance between parties sleeping sites on the same night. We further investigated patterns of sleeping site use of parties across time. We found that the vast majority of sleeping sites were in the gallery forest along the perennial Gambia River, likely due to the availability of tall trees. Guinea baboons slept in close spatial proximity (>50m) to at least one other party regardless of food availability and predator presence. Patterns of sleeping site use showed no evidence of predator or parasite avoidance. Thus, Guinea baboons in Simenti likely use the abundantly available sleeping sites opportunistically rather than being driven by intergroup competition or strategies for predator avoidance or reduction of the risk of parasite infection.