The word “chacma” is derived from the Hottentot (Khoikhoi) name for baboon, viz choachamma or choa kamma.
Chacma baboons (P. ursinus) are the largest members of the monkey family and are a highly social species that live in groups of four to 200 individuals. Within a troop, adult males form a dominance hierarchy that is established and maintained by fighting and aggression. Male ranking is unstable (6–12 months), because young males tend to emigrate between troops and high ranking males frequently lose their status to younger immigrants. In contrast, females remain in their natal groups and form strong hierarchies that transcend generations. Chacma baboons are largely omnivorous and are common in savannah woodland, steppes and sub-desert, montane regions (e.g. Drakensberg Mountains), Cape Fynbos and Succulent Karoo areas of southern Africa. Although the species is not threatened, increasing overlap between their natural range and human settlements has resulted in human-wildlife conflict.
A baboon uses facial expressions and body postures to communicate its level of excitement, anger and arousal. Friendly behavior is associated with non-threatening behavior such as soft grunts, avoiding eye contact and retracting lips to display clenched teeth. Presentation of the rump is used as an invitation by sexually receptive females and also as a conciliatory signal by baboons of both sexes. Adult males may sit with their erect penis in full view to communicate to other males that an adult is present in the troop. This also occurs when the male is on guard.
Aggressive behavior is associated with staring fixedly at an individual, displaying canine teeth and thrusting head and body postures that may be accompanied by shaking of grass and tree branches.
Baboons have a wide range of vocal signals that can be graded into one another and combined with each other and with visual signals in complex and subtle social communication.
The well-known ‘bokkum’ double bark is an alarm and aggressive signal given only by high-ranking males when there is inter- or intra-group aggression between males, and when a predator is nearby. The call also communicates male presence and arousal.
Chacma baboons inhabit a wide range of habitats and are common in woodland, savanna, steppes and sub-desert, montane regions of the Drakensberg, Cape Fynbos, Succulent Karoo and can be found on Sibuya Game Reserve. They normally occur in areas with adequate food and water supply and suitable night resting places such trees or high, rocky outcrops.