Context-Dependent Reactive Antipredator Behavior of Chacma Baboons (Papio ursinus griseipes) Amidst Predator Recovery.

Predation is a driving force in prey ecology and evolution, and primates exhibit diverse antipredator strategies for minimizing risk. Because these behaviors can be costly, individuals balance costs and benefits when responding to perceived threats. The cognitive capacity and behavioral plasticity of baboons make them an ideal taxon for studying the context-dependent variation in antipredator strategies. We used an autonomous, motion-activated playback experiment to study the behavioral responses of chacma baboons (Papio ursinus griseipes) to simulated predator encounters in Gorongosa National Park, Mozambique. We compared responses in 2021, when predator densities were relatively low, to 2024, after predation increased due to lion (Panthera leo) population recovery and African wild dog (Lycaon pictus) reintroduction. We compared flight and vigilance responses to vocalizations of these common predators with responses to leopard (Panthera pardus), historically a key predator; spotted hyena (Crocuta crocuta), a rare predator; and cheetah (Acinonyx jubatus), absent historically and currently. We assessed how responses varied with habitat, age-sex class, presence of offspring, and number of baboons in frame. Across 916 predator playbacks, baboons fled in 19% and displayed vigilance in 71%. When predator density was higher in 2024, baboons displayed weakened antipredator responses, possibly because baboons were more experienced with assessing risk, including risk associated with playback cues. Baboons were more likely to flee and more vigilant in response to leopard and wild dog cues. Juveniles fled more frequently than other demographics, while adult females with offspring were more vigilant. Responses were highly heterogeneous, reflecting behavioral flexibility characteristic of baboons.