The olive baboon is a large heavily built animal with sturdy limbs. They look rather doglike with their long, pointed muzzles, and in the way they walk on all four legs. They have very long tails. Their running resembles galloping, like a horse. Their jaws are very powerful and they have long, pointed canine teeth. Their eyes are set closely beneath a prominent brow ridge. Their ears are large, hidden amongst their thick fur. Adult males have a thick, gray furry ruff around their cheeks. Olive baboons have cheek pouches where they can store food as they forage. Young baboons are darker, almost black, and don’t have the heavy facial fur.
These baboons inhabit equatorial Africa from Senegal, across to northern Zaire, Ethiopia, Uganda, Kenya, and northern Tanzania, living in many different habitats within this large range. They are often found in the savanna, but also in moist, evergreen forests, rocky cliffs, dry woodland, open grassland and desert habitats, and near human settlements.
Baboons are diurnal, spending most of their time on the ground. At night they sleep in trees or cliffs, travelling as a family in the morning to feeding grounds. Before moving off is the time to socialize, while the young ones play. As the day moves towards its close, they go back to their sleeping quarters and again spend some time socializing, doing activities such as grooming, before they sleep. Olive baboons generally live in troops of between 20 to 60 animals, sometimes up to 100 individuals. In a typical troop the adult males number 7 or 8, with two times that number of females and their young. If troops come across each other, the larger group may cause the smaller one to be displaced, or they just ignore each other. These baboons communicate by means of vocalizations and a large range of facial expressions: staring, raising eyebrows, and baring their teeth are displays of aggression.
Baboons are omnivorous and are experts at foraging in all parts of the environment where they live: on the ground, under the ground and in the trees. They eat grasses, seeds, roots, fruit, leaves, bark, invertebrates, lizards, turtles, fish, frogs, eggs, the young of birds, young mammals, including other primates, and crocodile eggs. They eat whatever they can find. They shuffle with their hands and feet through the grass while they move or sit, in order to flush out a possible meal. In the zoo they are fed browse, mixed fruit and vegetables, grapes, bananas, nuts, bean sprouts, romaine lettuce, scratch grain, pigeon grain and parrot mix.
Both males and females are polygamous. They reach sexual maturity at the age of 7-10. Females seek out the males, generally the strong, well-established ones. There is no breeding season, though mating during the rainy season is more common. One baby is born, and rarely two, following gestation of about 187 days. A mother carries her newborn at her breast by holding it one arm, then at 4 or 5 weeks old a baby will sit on her back to ride. The baby first eats solid food when 5 or 6 months old, being weaned at 8 months. Females groom and play with the young. The male helps with rearing and grooming, and defends his females when necessary, the young ones often choosing to follow or sit next to the males.
Predators include all the big cats, such as lions and leopards, wild dogs, hyenas, chimpanzees and crocodiles. Their habitat is being destroyed by agricultural expansion, and when they raid crops they are systematically exterminated. The conflict that arises when baboons live beside humans sometimes leads to populations of baboons being relocated for the farmers’ benefit but also to save the baboons. They are sometimes hunted for sport and food.
The IUCN Red List and other sources don’t provide the number of the Olive baboon total population size. Currently this species is classifed as Least Cncern (LC) on the IUCN Red List and its numbers today are increasing.
Baboons presumably play a role aerating soil when they dig up corms, roots and tubers. Seeds from the fruits and grains they eat are likely to be dispersed.