Olive baboon

Advisory

We are currently in the process of updating this factsheet. Recent developments in our understanding of this primate may not be reflected in the content available today. If you’d like to contribute to writing, editing or peer-reviewing PIN content, please don’t hesitate to get in touch!

TAXONOMY

Suborder: Haplorrhini
Infraorder: Simiiformes
Superfamily: Cercopithecoidea
Family: Cercopithecidae
Subfamily: Cercopithecinae
Genus: Papio
Species: P. anubis

Other names: Papio hamadryas anubis; anubis baboon; babouin anubis (French); papión oliva (Spanish); olivbabian (Swedish)

Conservation status: Least concern

Life span: 25 to 30 years (wild)
Total population: Unknown
Regions: Equatorial Africa
Gestation: 180 days (6 months)
Height: 700 mm (M), 600 mm (F)
Weight: 24 kg (M), 14.7 kg (F) (wild)

MORPHOLOGY

Olive baboons have a greenish-grey coat covering their bodies. The individual hairs are green-grey with rings of black and yellowish-brown, giving the coat a multi-color appearance from up-close (Rowe 1996; Groves 2001). Infants are born with a black natal coat that changes to the adult coloration as they age. Adult males have long hair forming a mane from the top of their heads through their shoulders and which gradually shortens down the back (Groves 2001). The skin on their faces, ears, and ischial callosities is dark grey to black and covered with a very fine fur and they have a salt and pepper wreath of fur around their faces. Olive baboons have long, pointed muzzles rather than the flat faces characteristic of other primates, including humans, and because of their quadrupedal stance and locomotion, they appear quite dog-like (Nagel 1973). Their tails are long, between 380 and 584 mm (1.25 and 1.92 ft), and are held up and away from the rump for about a quarter of the total length, and then drop suddenly, giving the appearance that the tail is broken (Groves 2001). Like other cercopithecines, olive baboons have cheek pouches, specialized sacs on the inside of their cheeks than can be used for storing food as they forage (Rowe 1996).

Olive baboon on a branch
Papio anubis

Males and females are sexually dimorphic, with the males being about twice as large as females. The average height for captive and wild males is about 700 mm (2.30 ft) and females measure about 600 mm (1.97 ft) (Coelho 1985; Eley et al. 1989). Wild male olive baboons weigh 24 kg (52.9 lb), on average and wild females weigh 14.7 kg (32.4 lb) on average (Strum 1991). Where they live close to agricultural production and can raid crops, supplementing their natural diets with fruits, vegetables, and grains grown by local people, the average weights are slightly higher. Crop-raiding males weigh around 27.4 kg (60.4 lb) and females weigh 15.6 kg (34.4 lb) (Strum 1991). Captive olive baboons weigh more than their wild counterparts, with the weight of captive males averaging 29 kg (63.9 lb) and females averaging 17 kg (37.5 lb) (Coelho 1985).

RANGE

CURRENT RANGE MAPS (IUCN REDLIST):
Papio anubis

Olive baboons are widespread throughout equatorial Africa and are found in 25 countries. From the west coast of Africa moving eastward, olive baboons are found in Guinea, Mali, Mauritania, Sierra Leone, Côte d’Ivoire, Burkina Faso, Ghana, Togo, Benin, Nigeria, Niger, Chad, Central African Republic, Cameroon, Sudan, Ethiopia, Eritrea, and Somalia. The range of olive baboons extends southward into Uganda, Kenya, Tanzania, Rwanda, Burundi, Democratic Republic of Congo, and Congo (Groves 2001). Until 2001, a free-ranging population of olive baboons could be found in Spain, but they have subsequently been captured and transferred to zoos. This group of Spanish baboons was established when a group of 60 olive baboons escaped from a safari park and began ranging free on a governmental ranch in 1972 (Gil Burmann et al. 2002).

In the westernmost part of their natural range, in Guinea and Mali, olive baboons overlap with guinea baboons (Papio papio) but hybridization between the two species has not been studied. In the Awash River Valley in central Ethiopia, their range overlaps with hamadryas baboons (P. hamadryas) and the two species interbreed, forming a hybrid zone (Nagel 1973). These hybrid crosses have intermediate physical appearances of both species. There are other areas of overlap between olive and hamadryas baboons in Ethiopia, but the hybrids of the Awash Valley have been most closely studied (Nagel 1973). Olive baboons also hybridize with yellow baboons (P. cynocephalus) in Kenya and Tanzania, most notably in Amboseli National Park, Kenya. Historical and long-term crossbreeding of these two species may have contributed to the formation of the subspecies P. cynocephalus ibeanus (Alberts &Altmann 2001).

Research on wild, free-ranging olive baboons has been ongoing since 1978 at Masai-Mara National Reserve, Kenya by Robert Sapolsky and his colleagues. Robert Harding, followed by Shirley Strum and her colleagues at the Gilgil Baboon Project, also have added greatly to the knowledge about wild olive baboons in Kenya by studying them at Kekopey and Chololo Ranches, near Gilgil, Kenya since 1970. Ryne Palombit has also been studying baboons continuously since 2000 on Laikipia Plateau in Kenya. Gombe Stream National Park, Tanzania was made famous by Jane Goodall’s research on chimpanzees (Pan troglodytes), but olive baboons have also been studied here. The Southwest National Primate Research Center in Texas is home to the world’s largest captive baboon colony and most of the baboons studied there are olive baboons. Research on olive baboons has focused on genetic mapping and using them as a model for understanding the physiological changes associated with aging in humans (www.snprc.org).

HABITAT

Olive baboons live in a variety of habitats across their broad range. Baboons are generally characterized as savanna species, inhabiting open grassland near wooded areas (Rowell 1966). While olive baboons do inhabit grassland in much of their range, they are also found in moist, evergreen forests and near areas of human habitation and cultivation (Naughton-Treves et al. 1998). At Gilgil, Kenya, where olive baboons have been studied since the early 1970s, the habitat is open grassland with few trees. Kekopey and Chololo Ranches are situated in the central Rift Valley and are characterized by deep valleys that run parallel and which are separated by rocky cliffs. In these valleys, grassy plains are interspersed with occasional patches of shrub and only a few trees can survive in the rocky soils (Harding 1976). Rainfall is concentrated during a period of several weeks in November, and for a longer period stretching from April to June. Mean annual rainfall is between 595 and 756 mm (1.95 and 2.48 ft). The warmest months of the year are from December through March and the average daily temperature ranges from 10.6° and 25.5° C (51.1° and 77.9° F) (Harding 1976). Another site where baboons in Kenya have been studied is at the Laikipia Plateau in the central part of the country. Situated at an altitude of 1600 to 1700 m (5249 to 5577 ft), Laikipia consists of dry woodland and grassland dotted with stands of trees and thick shrubbery (Barton et al. 1992). Most of the trees are Acacia species and the understory of the woodland is made up of grasses, sedges, and xerophytic species (Barton &Whiten 1993). Additionally, outcroppings of steep rocky slopes and large boulders with sparse vegetation characterize the plateau and are known as kopjes. Mean annual rainfall is 549 mm (1.90 ft) and rainfall is concentrated in two rainy seasons, from March to June and November to December. Seasonal streams cut through the grassland; damming the streambeds has led to permanent waterholes. Average daily temperatures range from 12.4° to 37.2° C (54.3° to 99.0° F) and the hottest month of the year is February (Barton et al. 1992; Barton &Whiten 1993).

Olive baboon in a tree
Papio anubis

Olive baboons are also found in Ethiopia. In the Bole Valley, olive baboons range from the valley bottom, found at an altitude of 1700 m (5577 ft) to the plateau which rises over the valley floor to an altitude of 2300 m (7546 ft) (Dunbar & Dunbar 1974). The baboons utilize all habitats found from the valley floor to the plateau. In the riverbed, the lowest point of Bole Valley, gallery forest abounds and trees up to 30 m (98 ft) in height grow with a thick understory of shrubs and grasses. Moving up the slopes of the valley, the trees give way to more open grassland interspersed with thickets and eventually, as the altitude increases, open grassland dominates the environment. At the top of the plateau, stands of trees and thickets are scattered across the grassland (Dunbar & Dunbar 1974). The rainy season lasts from July to early September and the dry season from mid-September to June, with an average of 2000 mm (6.56 ft) of rain falling each year. Daytime temperatures remain around 35° C (95° F) throughout the year (Dunbar & Dunbar 1974). Baboons have been intensely studied elsewhere in Ethiopia at the Awash River Valley. Along the Awash River, gallery forest dominates the landscape, with the canopy remaining less than 20 m (65.6 ft) in height and with a thin understory (Aldrich-Blake et al. 1971). Moving away from the river, the landscape transitions into thorny scrub with areas of trees. A dormant volcano, Mount Fantalle, has been recently active, creating lava fields and cliffs mixed with bare rock and dry, flat areas bordering the savanna. This area of Ethiopia is considered arid, with short rains falling in February and March and another, longer rainy season lasting from July to September (Aldrich-Blake et al. 1971). Average annual rainfall ranges between 533 and 774 mm (1.75 and 2.54 ft), but some years can be unusually dry. Average daily temperatures range between 18 and 31° C (64.4 and 87.8° F), but on the lava fields can be much higher (Aldrich-Blake et al. 1971).

In neighboring Eritrea, olive baboons live in arid and moist lowlands below 900 m (2953 ft) characterized by riverine forest bordered by savanna. Average rainfall in their Eritrean range is 544 mm (1.78ft) per year (Zinner et al. 2001). In Pendjari National Park, Benin, surveys of olive baboons reveal that they too inhabit gallery forests and savanna interspersed with open woodland (Sinsin et al. 2002). The climate is dry, but rains fall starting in April or May and last until October. Most rain falls in August and September and the average annual rainfall is 1000 mm (3.28 ft) per year, but the distribution over time and space is highly variable. The average temperatures range from 12 to 40° C (53.6 to 104° F) and the hot climate, coupled with variable rainfall patterns leads to periods of drought (Sinsin et al. 2002). In Ghana, olive baboons also live in savanna woodland where thickets and dry forest intersperse open grassland. In the Shai Hills, rocky outcroppings and hills rise above the grassland and small trees and wooded areas are found on plateaus (Lieberman et al. 1979). At 26.4° C (79.5° F), the average temperature is moderate. Small amounts of rain fall during the two rainy seasons from March to July and September to November, and average annual rainfall is 733 mm (2.40 ft) (Lieberman et al. 1979).

Not all olive baboons live in open woodland bordered by savanna. In many of their range countries, they live in evergreen tropical forests. In Uganda, both types of habitat exist and olive baboons utilize each. At Queen Elizabeth National Park, situated near the border of Democratic Republic of Congo, where olive baboons are also found, the habitat is characterized by dense forest surrounding the Ishasa River which slowly transitions from forest edge to coarse wet grass, then short grass with sandy areas, to low bush, and then to open grassland dotted with solitary trees and tall shrubs and bushes (Rowell 1966). At Kibale National Park, in western Uganda, olive baboons live in moist, evergreen forest bordered by swamp, grassland thickets, and secondary forests. Around the park, local families have cleared forest for subsistence agriculture. With a variety of cultivated crops growing near their habitat, olive baboons have become notorious crop-raiders, supplementing their diets with maize and bananas (Naughton-Treves et al. 1998). Across the park, rainfall varies from 1100 to 1600 mm (3.61 to 5.25 ft) per year and annual average daily temperature ranges from 23.3 to 24.2° C (73.9 to 75.6° F) (Naughton-Treves et al. 1998).

ECOLOGY

Olive baboons are ecologically flexible in that they consume a wide variety of foods and can live in a variety of habitats, but nonetheless they are selective about their diet choice and habitat usage (Whiten et al. 1991; Barton et al. 1992). Olive baboons can be found in habitats ranging from desert to montane forest. One reason they are able to adapt to these varying habitats could be their flexibility in foraging strategies and ability to extract food and nutrients from almost all strata of the environment (Whiten et al. 1991). They find food on the ground, in the trees, and underground. On the ground, they forage in the grass or in thickets of savanna woodland, they forage in trees and find food at higher levels of the canopy, and finally, they dig up subterranean foods (Whiten et al. 1991). Baboons are omnivores and consume a huge variety of items including roots, tubers, corms, fruits, leaves, flowers, buds, seeds, bark, exudates, cacti, grasses, insects, birds, bird eggs, and vertebrates (including other primates) up to the size of a small antelope (Rowell 1966; Dunbar & Dunbar 1974; Harding 1976; Whiten et al. 1991; Hassan 2001). Olive baboons are generally opportunistic hunters, capturing prey as they come across it, but at Gilgil, Kenya, olive baboons exhibit simple and complex hunting patterns (Strum 1981). For baboon predation to be considered simple hunting, it requires active searching and stalking or chasing of the prey, usually a small antelope, ground-dwelling bird, or other small mammal. Thomson’s gazelles make up 33% of the prey eaten by olive baboons (Strum 1983). Simple hunting involves only one baboon and the pursuit of the prey lasts less than 10 minutes and occurs within 300 m (.186 mi) of the rest of the baboon troop (Strum 1981). Complex hunting involves more than one baboon, a pursuit of prey lasting longer than 10 minutes and ranging greater distances from the group during the chase, between 300 and 4000 m (.186 and 2.49 mi). Both male and female olive baboons hunt (Strum 1981). In the relatively richer forest environments where they are found, olive baboons rely heavily on fruits compared to seeds and grasses consumed by savanna-living baboons (Ransom 1981).

Olive baboon
Papio anubis

In many areas of their range where human populations are increasing, olive baboons raid agricultural crops for food and feed on garbage and human refuse (Forthman Quick 1986; Eley et al. 1989; Naughton-Treves et al. 1998). Feeding close to human populations influences group behavior among olive baboons and may also influence social structure (Forthman Quick 1986). At Gilgil, the conflict between farmers and baboons became so intense that by 1984, more than 130 baboons were trapped and translocated in an attempt to appease farmers and save the baboons from persecution (Strum 1987).

Rainfall is directly correlated with food availability in many habitats. In savanna areas, the food availability is highest near the end of the rainy season and gradually decreases in abundance as the dry season continues (Barton et al. 1992). During the rainy season, fruit, young leaves, and flowers are abundant and important foods for olive baboons. As the dry season progresses, these foods become scarce and baboons must switch to other resources (Barton et al. 1992). One way that olive baboons deal with the scarcity of food is to utilize subterranean food sources such as roots, tubers, and corms (Barton & Whiten 1993). Olive baboons are good diggers and use their hands to unearth the roots of plants (Nagel 1973). Seeds are also an important food resource during the dryer times of the year (Barton et al. 1992). In Uganda, olive baboons do not experience the limited availability of food plants seen in the savanna portions of their range. Plants follow an annual cycle of flowering and fruiting, but there are no seasons in which a wide variety of food plants are not available (Rowell 1966).

In the Bole Valley, Ethiopia, olive baboons have home range sizes between .745 and 1.12 km² (.288 and.432 mi²) and range between .3 and 2.0 km (.186 and 1.24 mi) per day (Dunbar & Dunbar 1974). In one study at Laikipia Plateau, Kenya, home range and day length sizes were much larger than in the Bole Valley. Home range size was 43.8 km² (16.9 mi²) and the average distance traveled per day was 5.64 km (3.50 mi) (Barton et al. 1992). The drastic differences in habitat use can be partly attributed to group size. As group size increases, so does home range size and day range length (Barton et al. 1992). The study population used by Barton et al. (1992) numbered about 100 olive baboons while Dunbar and Dunbar (1974) studied seven groups ranging in size from 15 to 24 animals. This relationship exists because larger groups experience increased competition for resources such as food; therefore the area covered each day and subsequently the home range within which the group forages increases to accommodate the needs of a larger number of animals (Barton et al. 1992). At Gilgil, Kenya, the home range size of a group of 49 baboons was 19.7 km² (7.60 mi²) but 75% of their time was spent in a core area about 25% of the total size of the home range (Harding 1976). The average day length for the study group at Gilgil was around 5 km (3.11 mi), with the shortest distance traveled being 2.2 km (1.37 mi) and the longest day journey being 7.8 km (4.85 mi) (Harding 1976). At Ishasa, Uganda, where olive baboons spend up to 60% of their time in the rich, forested areas, home range size ranges between 3.88 and 5.18 km² (1.5 and 2 mi²) and day range length can be as short as a few hundred meters and up to 2.4 km (1.5 mi) (Rowell 1966). At Gombe, Tanzania, another forested site where olive baboons have been studied, home ranges average 3.88 to 5.18 km² (1.5 to 2 mi²) (Ransom 1981).

Olive baboon
Papio anubis

As seasonal rainfall influences food availability, it in turn affects home range size and daily ranging patterns (Nagel 1973; Harding 1976; Ransom 1981; Barton et al. 1992). Daily activity patterns are also variable, depending on the season and climatic conditions. Departure from the sleeping site, the time spent traveling, the maximum distance traveled from the sleeping site, the number and length of resting and feeding periods, and the distance covered per day are all variable from one day to the next and from one group of baboons to the next (Nagel 1973). The general pattern observed is a period of socializing after waking, moving from the sleeping site and feeding, resting, and then alternating feeding and resting until late afternoon at which time the group travels back to the sleeping site. Most social activities occur during the periods of rest throughout the day (Strum 1987). The home ranges of several groups of baboons often overlap, and when groups come into contact with one another, the larger group displaces the smaller group or the two groups largely ignore each other (Aldrich-Blake et al. 1971; Smuts 1985). In many cases, the adult males within the group with chase the adult females of their troop away from the other troop. They threaten females presumably to reduce the contact of group females with outside males (Packer 1979a).

Olive baboons seek sleeping refuges in trees or on rocky cliffs, depending on availability (Aldrich-Blake et al. 1971; Nagel 1973; Harding 1976; Hamilton 1982). Open cliffs, free of extensive woody vegetation and with near-vertical slopes are preferred as nighttime sleeping spots (Hamilton 1982). When cliffs are not available, olive baboons prefer emerging trees, those that protrude from the surrounding canopy, to any other tree sleeping site such as closed canopy, where trees are close enough to each other that baboons can transverse the canopy without coming to the ground, or open woodland, where trees are separated to the degree that baboons must come to the ground to get into a neighboring tree (Hamilton 1982). One reason they are selective about sleeping sites is to increase protection from predators. Some of the known predators of baboons include large cats, which have a difficult time scaling rocky walls because they cannot find holdings for their paws as well as baboons can for their hands and feet, explaining why cliffs and rocky ledges are preferred to trees when both are available (Hamilton 1982). Besides felids such as lions, leopards, and servals, other potential predators of olive baboons include wild dogs, hyenas, chimpanzees, crocodiles, and raptors, which are a more serious threat to juveniles and infants (Rowell 1966; Nagel 1973; Harding 1976; Barton et al. 1996). Domestic dogs are also potentially serious predators of baboons (Smuts 1985).

Content last modified: April 18, 2006

Written by Kristina Cawthon Lang. Reviewed by Ryne Palombit.

Cite this page as:
Cawthon Lang KA. 2006 April 18. Primate Factsheets: Olive baboon (Papio anubis) Taxonomy, Morphology, & Ecology . <http://pin.primate.wisc.edu/factsheets/entry/olive_baboon/taxon>. Accessed 2020 July 16.

SOCIAL ORGANIZATION AND BEHAVIOR

Olive baboons live in groups or “troops” as they are often called, ranging in size from 15 to 150 individuals (Rowel 1966; Dunbar & Dunbar 1974; Ray & Sapolsky 1992). Within the troop, there are several adult males, numerous adult females and their offspring of various ages. Females almost always remain in their natal group for their entire lives whereas males disperse in order to mate (Packer 1979a; Smuts 1985; Barton & Whiten 1993; Barton et al. 1996). Because females do not emigrate but rather stay and breed with immigrant males, some females within a group are closely related. Mothers, daughters, grandmothers, aunts, and nieces associate with each other as a subgroup of the larger troop. A stable linear dominance hierarchy exists within and between these matrilineal subgroups (Smuts 1985; Barton &Whiten 1993). Rank among females is passed down through the mother so that daughters rank just below their mothers and groups of related females are ranked higher or lower than other groups of matrilineal kin. Female relatives exchange friendly behaviors like grooming and remaining in close proximity to one another as well as supporting one another during agonistic encounters with other troop members, both male and female (Smuts 1985; Barton & Whiten 1993; Barton et al. 1996). In addition to having high-ranking supporters, dominance confers benefits to females, including increased access to food and higher reproductive success (Barton & Whiten 1993). Females also interact with one or two male members of the group and form long-lasting, social relationships that have been characterized as “friendships” (Smuts 1985). These friendships between male and female baboons include frequent, relaxed grooming sessions, traveling and foraging together throughout the day, sleeping near each other at the sleeping site, defense from aggressive conspecifics, and support in caring for infants (Aldrich-Blake et al. 1971; Smuts 1985). Friendships are sometimes formed when females are sexually receptive and approach newly immigrated, strange males to solicit mating through presentation of their swollen rumps or through grooming, but the bond can also begin between anestrous females and males and can persist into the cycling period of the female (Smuts 1985; Bercovitch 1991). Once a male accepts a female, the relationship becomes long-lasting and the two preferentially groom and remain in close proximity with one another. When females come into estrus, they tend to decrease the time associated with specific partners, but still strongly interact with their male friends (Smuts 1985). The dissolution of friendships occurs when males transfer to another group or when estrous females form new friendships with younger, more newly transferred males while cycling (Bercovitch 1991).

Olive baboons
Papio anubis

Unlike females, males leave their natal group and join another group after they reach sexual maturity. Transfer occurs after puberty, between six and nine years of age, when males have reached or are near their adult size (Packer &Pusey 1979; Smuts 1985). After leaving their natal group, males will transfer several more times over the course of their lives, to avoid breeding with their offspring (Packer 1979a; Sapolsky 1996). Because adult males within a group of olive baboons are not related, they often compete with each other, either directly or indirectly, for access to females (Smuts 1985). As a result, adult males generally associate with one another in tense, highly competitive ways (Aldrich-Blake et al. 1971; Smuts &Watanabe 1990). Older males, those past their physical prime or at least 14 years of age, generally have more cooperative, egalitarian, and relaxed relationships with each other compared to younger males, those that are in their physical prime and between the ages of eight and 11 years, and they work together, forming coalitions to displace younger males and prevent them from gaining mating opportunities (Smuts &Watanabe 1990). Even though they are capable of ganging up on younger group members, older adult male baboons do not rank highly in the dominance hierarchy that exists among males of the group. The hierarchy generally follows age, with the young adult males, both natal and transfers, ranking higher than older, long-term resident males (Smuts 1985). Both physically prime young adults and older adult male olive baboons outrank subadult males, those between the ages of about five to eight years old. Rank is contested, defended, and reinforced through agonistic interactions as well as other, friendlier interactions. Fights between adult males occur almost daily and injuries are common. In addition to wounds sustained during physical confrontations, subordinate males suffer higher levels of stress merely in the presence of higher-ranking males which can lead to health problems over time (Sapolsky &Share 2004). The dominance hierarchy among males is separate from the female dominance hierarchy within the group (Packer &Pusey 1979). Females do not always prefer high-ranking males as mates, but rather choose familiar males that are older and have been in the group for longer periods of time and with which they have spent time (Packer &Pusey 1979; Smuts 1985). Older male olive baboons also form coalitions with each other and work together to prevent a younger male from mating with an estrous female. (Smuts &Watanabe 1990). The social patterns exhibited by olive baboons vary across study groups and across sites such that at some sites, the dominance hierarchy is arranged differently and the effect of rank on access to cycling females may be more noticeable among some populations compared to others (Palombit pers. comm.).

Ritualized greetings between males are the most common form of male-male social contact in olive baboons and happen in socially neutral situations; that is, they are seen when there are no resources such as food or females at stake (Smuts &Watanabe 1990). The greeting begins when one male approaches another with a rapid, stereotyped gait, looking directly at the other male, smacking his lips, squinting, laying his ears flat against his head, and finally presenting his hindquarters (Smuts &Watanabe 1990). These are all affiliative signals in baboon communication and the male being approached either responds with similar facial expressions or turns away from the presenting male, rejecting the greeting. These greeting rituals can be characterized as tense and tentative, but seemingly serve the purpose of reinforcing the dominance hierarchy during times of relative calm. Non-aggressive greeting behavior may be beneficial to males because if they are able to reinforce their rank in relation to one another, during times of resource competition and high social anxiety, less physical confrontation may be necessary (Smuts &Watanabe 1990). Greetings between older males may also be important in solidifying cooperation while younger, higher-ranking males rarely complete the greeting ritual and are more likely to fight for a position of dominance (Smuts &Watanabe 1990).

REPRODUCTION

Olive baboon
Papio anubis

Both males and females reach sexual maturity between four and six years of age. Males do not reach full adult size until they are about 10 years old in the wild and between seven and eight years in captivity (Smuts 1985; Bercovitch 1989). Sexual maturation in male olive baboons is characterized by enlargement of the testicles, growth of the canine teeth, which are much larger in males than females, a deepening of the voice, and an increase in body size and bulk (Jolly & Phillips-Conroy 2003). Females continue to grow and reach their adult size within three years after puberty and give birth one to two years after they begin cycling (Smuts 1985; Smuts &Nicolson 1989). The average ovarian cycle lasts 37.5 days in wild olive baboons and is characterized by sexual swelling common among Old World monkeys. Swelling lasts for about 18 days, and ovulation is probably during the final week of swelling, as the tumescence subsides (Bercovitch 1991). The skin in the anogenital region becomes swollen and bright pink or red and serves as a signal of reproductive quality to males. These swellings can increase a female’s weight by up to 14% and can often be burdensome. Females cannot move or sit as easily when swollen and are subject to bacterial and parasitic infections if the skin is cut or torn (Domb &Pagel 2001). Displaying such vivid signs of receptivity has an important function for females. Females with larger swellings reproduce at a younger age, produce a larger number of offspring per year, and a larger number of those offspring survive. Males are more attracted to females with larger swellings, contest mating more aggressively, and are likely to suffer from multiple followers and intruders during mating with females that have large swellings (Domb &Pagel 2001).

Mating among olive baboons is promiscuous; both males and females have multiple mates. One characteristic of baboon reproductive behavior is the formation of mating consortships, defined as continuous close spatial association between a male and a sexually receptive female characterized by copulatory activity (Packer 1979a). Olive baboons form these exclusive relationships, lasting a few minutes or up to two weeks in length, in which they copulate frequently and where the male prevents other males from mating with his consort partner (Bercovitch 1983; 1991). During this time, the pair may separate themselves from the group during the day, traveling within the sight of, but separately from, the main troop (Bercovitch 1983; Forster &Strum 1994). Furthermore, the consorting male protects the female from other males who attempt to mate with her and severe fights between males can occur. This is especially true during the most fertile time of her cycle, during the final few days of tumescence, when male challenges are significantly higher than during other times of the female’s cycle (Bercovitch 1989; Jolly &Phillips-Conroy 2003). Females are involved in consortships with an average of three to four males and ranging up to nine different males over the period of fertility.

Olive baboon mother and infant
Papio anubis

There is no seasonality in baboon reproduction; females cycle and give birth throughout the year (Bercovitch & Harding 1993). Gestation lasts about six months (180 days). The average interbirth interval at Gilgil , Kenya is about two years (760 days), but can vary greatly depending on a number of factors (Smuts & Nicolson 1989). For example, high-ranking females have shorter interbirth intervals than lower-ranking females in a group. This may be linked to nutrition and food availability to low-ranking members of the group (Smuts & Nicolson 1989). The amount of time between births is also affected by the survival of the previous offspring. If a female loses an infant, she resumes cycling within a month and will reproduce sooner than if she successfully raised the infant. Age also affects interbirth intervals , with older females having a shorter time between births than younger females (Smuts & Nicolson 1989).

PARENTAL CARE

While both male and female olive baboons take part in caring for infants, the majority of care provided is by their mothers. They are acutely dependent on their mothers for food and travel for the first several months of life. Infant olive baboons are born with bright pink skin and black coats. As they age, their skin darkens and they lose their natal coats. By six months, their coats have transitioned from black to the olive color characteristic of adults (Ransom & Rowell 1972). For the first few days of life, the mother physically supports the infant, which may have a difficult time grasping on to her for long periods of time. Within the first week of life, though, its grasp will strengthen and it will be able to support itself, clinging to the mother’s fur for long periods of time. As soon as two weeks of age, the infant may break physical contact with the mother to investigate the ground and food items such as grass, but only for a few minutes at a time, and never far from the mother (Ransom & Rowell 1972). By three weeks, the infant may try to move away from the mother as it explores its surroundings, but it is quickly retrieved. For the first 10 months, the infant is within arm’s reach of the mother at least 50% of the time, but the distance between mother and infant quickly increases as the infant ages so that by one year of age, the infant spends at least 50% of its time in distances greater than 8.5 m (27.9 ft) of its mother (Nash 1978).

Olive baboon mother and infant
Papio anubis

As infants spend less time near their mothers, they increase the time spent playing by themselves or with their peers. For the first month of life, infant olive baboons nurse and sleep frequently, but as they age, their activity levels increase (Ransom &Rowell 1972). Nursing decreases over the first year of life, with the most significant decrease in time spent nursing occurring between 10 months and one year of age, when young baboons are weaned (Nash 1978). Mothers begin to reject nursing attempts by young olive baboons as early as six months of age. Though they do not nurse after being weaned, young baboons often take the nipple in stressful situations, which seemingly calms them. They can continue to do this until the mother has another infant or as long as the mother will allow it (Nash 1978). Infant baboons also depend on their mothers for transportation. While they initially cling to their mothers’ ventrum, around three months of age they transition to riding “jockey style” on their mothers’ backs (Ransom &Rowell 1972). Riding continues until the end of the first year in most instances and the mother rejects the infant’s attempt to cling to her or climb on her after this age (Nash 1978).

It is advantageous for an adult natal male to care for an infant because he is likely related to it, either as a sibling, uncle, or cousin; caring for his young relative increases his inclusive fitness (Packer 1980). It is unusual for non-natal adult males to care for infants because, as is often seen in other nonhuman primate species where males and females mate promiscuously, males are not certain of their paternity and caring for an unrelated infant is a waste of time and energy (Packer 1980). While adult males protect infants that could be their offspring, thereby increasing their own fitness, the benefits of caring for unrelated infants also outweigh the costs incurred. Adult males decrease the probability of being threatened by other males if they are carrying infants (Packer 1980; Smith &Whitten 1988). This behavior is potentially hazardous for the infant, as the mere presence of an infant does not always deter a high-ranking male from directing physical aggression at a lower-ranking male. If two males begin to fight, the infant certainly is in danger of being injured or killed (Packer 1980). Additionally, the infant is often handled roughly as it is being picked up by the threatened male and vocalizes loudly, indicating its distress (Packer 1980; Smith &Whitten 1988).

Despite being exploited by adult males in some instances, infants benefit from a caregiving relationship with an adult male. Males groom infants, calming them during stressful periods and potentially decreasing ectoparasitic loads (Packer 1980). Another tangible benefit to infants is that adult males are capable of protecting infants from predators. At Gombe, Tanzania, where chimpanzees often hunt and capture young olive baboons, the mere presence of an adult male deters chimpanzees from attempting to catch a young baboon (Packer 1980). Additionally, adult resident males protect infants from newly immigrant males and other conspecifics. Infanticide by newly transferred males has been recorded in Tanzania and circumstantial evidence has been found at Gilgil, Kenya (Smuts 1985; Palombit 2003). When an infant dies, its mother resumes cycling much more quickly than if she had nursed and weaned the infant, beginning to cycle after the infant had gained independence. One hypothesis about infanticidal behavior is that male primates and other animals use infanticide as a way to induce cycling and increase their own reproductive success after joining a group (Hrdy 1974).

COMMUNICATION

Olive baboon mother and infant
Papio anubis

Vocal and visual communication is important to olive baboons and serves to convey affection, aggression, wariness, and intent (Strum 1987). One of the most common vocalizations given by olive baboons of all ages is the “basic grunt”, heard throughout the day as the group spreads out to feed, while traveling, during amicable social interactions, and as they settle into the sleeping site in the evening (Ransom 1981; Smuts 1985). Other vocalizations are heard under more specific conditions. Some calls given by adults include the “roargrunt”, “cough-bark”, and “cough geck”. The “roargrunt” is heard in displays by adult males, this call is given through closed lips and is deep in pitch and sounds like a low humming. Given in situations of low anxiety, alarm, or discomfort, the “cough-bark” and “cough-geck” may be heard in response to unknown humans or low-flying birds (Ransom 1981). Other calls given by all group members include “two-phased barks” or “wa-hoos”, “broken grunting”, “pant-grunts”, “shrill barks”, and “screams”. The “wa-hoo” is a two-syllable call given in series, ranging from one to 20 minutes in length in response to predators, during times of distress, such as when a baboon is separated from the group and trying to regain contact, and at night at the sleeping site in response to neighboring groups’ “wa-hoos” (Ransom 1981). “Broken grunting” is heard in all age groups except the youngest infants and is a low volume, rapid series of grunts given during low intensity aggressive encounters. If these aggressive encounters intensify, the vocalization shifts from “broken grunting” to “pant-grunts”, much louder, two-syllable vocalizations in which the first syllable is an inhaled “huh” and the second syllable is an exhaled “uh” (Ransom 1981). “Shrill barks” are loud, explosive calls given in alarm to sudden appearances of potential threats such as humans and which elicit startle responses in other group members. Heard in the most stressful situations, “screams” are any high-pitched, continuous sound in response to intense emotion including pain, fear, and aggression (Ransom 1981; Strum 1987). There are a few calls given only by juveniles and infants including “moans”, “basic gecks”, and “panting”. Both “moans” and “basic gecks” are distress calls given in times of discomfort, fear, separation from the mothers, weaning, and during tantrums. “Panting” is heard during rough-and-tumble play, presumably when young olive baboons are having fun, and sounds like breathy laughter (Ransom 1981).

In addition to vocalizations, baboons have a repertoire of visual displays that convey emotion, intent, and other information to conspecifics. General greeting signals include “lipsmacking”, “tongue protrusion”, “jaw-clapping”, “ear flattening”, “eyes narrowed”, and “head shaking”. These facial expressions are sometimes accompanied by a “rear present” (Ransom 1981). Like the “grunt” vocalization, “lipsmacking” is a common behavior heard in a variety of social contexts including grooming and sexual behavior. It conveys affiliation, reassurance, appeasement, submission, and content (Easley &Coelho 1991). Agonistic postures are also important in olive baboon communication as precursors to physical attacks. “Staring”, “eyebrow raising”, “yawning”, and “molar grinding”, are all threatening facial expressions, though they increase in the intensity of threat they intend to convey as they build on each other. The “eyebrow raising” display, a signal of mild threat or annoyance, is particularly notable because olive baboons have white eyelids, made visible as they raise their eyebrows and creating a striking display. Additionally, adult males give the “yawning” display, the length of their canines is exaggerated and when given in concert with “eyebrow raising” indicate increasing levels of threat (Ransom 1981; Strum 1987). When giving a threat display at a distance, olive baboons bob their heads, adopt a rigid quadrupedal stance known as a “stiff arm threat” and slap the ground or employ other objects such as branches or small trees to display aggression (Ransom 1981). In response to aggressive displays, there are also a suite of submissive displays given by olive baboons including “rigid crouch”, “tail erect”, and “fear grin” (Ransom 1981; Strum 1987).

SPECIAL NOTES

One unusual characteristic seen in young olive baboons in Nigeria is their ability to swim and dive. They have been observed swimming, with their faces submerged in a river, and diving from trees overhanging the river. They have not been observed foraging during these activities, and presumably swimming and diving is a form of play among these baboons (Pfeyffers 1999-2000). Furthermore, at the site where they are often observed swimming, hot springs join the river and human tourists also enjoy swimming here. Other baboons that range near this river have not been recorded swimming or even wading in the river and there are no other published reports from outside of Nigeria of this behavior in olive baboons; this behavior may represent cultural differences between neighboring groups of olive baboons (Pfeyffers 1999-2000).

Content last modified: April 18, 2006

Written by Kristina Cawthon Lang. Reviewed by Ryne Palombit.

Cite this page as:
Cawthon Lang KA. 2006 April 18. Primate Factsheets: Olive baboon (Papio anubis) Behavior . <http://pin.primate.wisc.edu/factsheets/entry/olive_baboon/behav>. Accessed 2020 July 16.

INTERNATIONAL STATUS

CONSERVATION STATUS

CITES: Appendix II (What is CITES?)
IUCN Red List: P. anubis: LC (What is Red List?)
Key: LC = Least concern
(Click on species name to see IUCN Red List entry, including detailed status assessment information.)

Olive baboon
Papio anubis

CONSERVATION THREATS & POTENTIAL SOLUTIONS

Threat: Human-Induced Habitat Loss and Degradation

Baboons are highly adaptable animals that are able to exploit a number of different environments (Ransom 1981; Strum 1987). Even when humans clear areas for cultivation or develop infrastructure on land, olive baboons are capable of exploiting new food resources, including agricultural products and refuse (Forthman Quick 1986).


Threat: Invasive Alien Species

While olive baboons and other primates are subject to a number of naturally occurring pathogens and parasites which can be harmless or cause only mild problems, other infections have been recorded to be serious within certain populations (Farah et al. 2003). In 1982, an outbreak of tuberculosis introduced through eating infected beef caused high levels of morbidity among a Kenyan population of olive baboons (Sapolsky & Else 1987). The group in which the disease originated lived nearby humans who raise and slaughter cows. The adult males of the group often frequented the slaughterhouse’s dump to feed and were infected through consumption of contaminated beef. Tuberculosis spreads quickly among captive nonhuman primates and results in weight loss, coughing, lethargy, and death (Sapolsky & Else 1987). Because of the movement patterns of male baboons, including natal and secondary transfer, diseases like tuberculosis can spread over a large area and to multiple groups. While new accounts of this disease have not been recorded in wild olive baboon populations, the potential for another outbreak is possible if sanitation standards are not increased. Proper disposal of infected beef could prevent the baboons from scavenging meat and decrease the possibility of transmission (Sapolsky & Else 1987).

Natural predators of olive baboons include felids, wild dogs, hyenas, chimpanzees, crocodiles, and raptors, but as baboons come into close proximity with humans, domestic dogs become more of a threat (Rowell 1966; Nagel 1973; Harding 1976; Smuts 1985; Barton et al. 1996).


Threat: Harvesting (hunting/gathering)

Olive baboons are hunted for food in some populations, but compared to other primate species, they are not harvested at high rates (Fa et al. 2005). They are killed by being shot or by being trapped in wire snares (Isabirye-Basuta 2004).


Threat: Persecution

Baboons are highly adaptable and exploit many food resources, including agricultural crops which neighbor their natural habitat. In some areas, human encroachment has increased greatly and olive baboons have become a serious pest species, raiding crops on a regular basis and finding much of their food in human-centered areas. These behavioral patterns have led to serious consequences for some baboons as farmers poison, trap, and shoot problem baboons (Ransom 1981; Naughton-Treves et al. 1998; Hill 2000). Olive baboons are particularly problematic and threaten the livelihood of farmers because of their destructive behaviors while raiding crops. They often dig up, snap off, or otherwise destroy a plant when they eat it. A group of baboons can cause serious damage to a subsistence farm, causing backlash from farmers (Hill 2000). While there are some solutions that decrease crop raiding on individual farms, as more land is converted to agricultural use and baboon habitat shrinks, more extensive measures may be necessary to decrease conflict and save baboons (Strum &Southwick 1986).

Potential Solutions

Several techniques have been used to decrease crop-raiding behavior in olive baboons including playback of alarm calls to frighten the raiders, chemical deterrents, and guard dogs. While each of these will work for a limited amount of time, because of the intelligence of baboons, the offending animals will learn to avoid these or will simply ignore them (Strum 1987; 1994). One extreme measure that has been successful in decreasing baboon mortality due to human persecution is relocation of baboons from areas of high human density and agriculture to areas of low human density (Strum 1987; Strum & Southwick 1986). In 1984, three troops of olive baboons were relocated from Gilgil, Kenya after precipitous decline in the main population due to persecution by farmers (Strum 1987). The baboons were moved to the less populated but equally ecologically suitable Laikipia Plateau, Kenya. This translocation involved 131 baboons, of which all survived and adapted to life in their new surroundings (Strum 1987). While this is an extreme measure, the pioneering work of Shirley Strum and her colleagues proved how successful and safe relocation could be for baboons and, depending on the circumstances, could be a tactic used for other populations of olive baboons suffering from persecution.


Threat: Natural Disasters

Savanna ecosystems are subject to periodic droughts that can have severe effects on the wildlife. Decreased rainfall affects grass regeneration and other plant growth, forcing olive baboons to spend more time foraging and inducing some physiological changes as well. Males have lower levels of testosterone during drought and females can potentially have difficulty reproducing (Sapolsky 1986). Malnourishment has not been reported during times of drought mainly because baboons adapt to rainfall shortages by increasing time spent feeding and traveling and decrease energetically expensive behaviors such as aggressive interactions and copulation (Sapolsky 1986).


Threat: Changes in Native Species Dynamics

Hybridization occurs between olive baboons and hamadryas (Papio hamadryas) as well as yellow baboons (Papio cynocephalus) in the wild (Samuels & Altmann 1986; Nagel 1973). Because the behavior is similar between these species and because they produce offspring that are healthy and can reproduce, natural hybrid zones form where the ranges of these species meet (Phillips-Conroy et al. 1988; Alberts & Altmann 2001). Hybrids have phenotypic and behavioral characteristics of both species and may be more successful than each of the species alone at exploiting the marginal environment (Bergman & Beehner 2004). While considered a natural phenomenon, increased hybridization has been recorded in recent years. At Amboseli National Park, Kenya human cultivation has increased in recent years, forcing olive baboons into more overlapping areas with yellow baboons and increasing the amount of hybridization (Alberts & Altmann 2001). There is no current evidence that increased hybridization threatens olive baboon populations at Amboseli (Detwiler et al. 2005).

LINKS TO MORE ABOUT CONSERVATION

CONSERVATION INFORMATION

CONSERVATION NEWS

ORGANIZATIONS INVOLVED IN Papio anubis CONSERVATION

Content last modified: April 18, 2006

Written by Kristina Cawthon Lang. Reviewed by Ryne Palombit.

Cite this page as:
Cawthon Lang KA. 2006 April 18. Primate Factsheets: Olive baboon (Papio anubis) Conservation . <http://pin.primate.wisc.edu/factsheets/entry/olive_baboon/cons>. Accessed 2020 July 16.

 

REFERENCES

Alberts SC, Altmann J. 2001. Immigration and hybridization patterns of yellow and anubis baboons in and around Amboseli , Kenya . Am J Primatol 53(4): 139-54.

Aldrich-Blake FPG, Bunn TK, Dunbar RIM, Headley PM. 1971. Observations on baboons, Papio anubis, in an arid region in Ethiopia. Folia Primatol 15: 1-35.

Barton RA, Byrne RW, Whiten A. 1996. Ecology, feeding competition and social structure in baboons. Behav Ecol Sociobiol 38(5): 321-9.

Barton RA, Whiten A. 1993. Feeding competition among female olive baboons, Papio anubis. Anim Behav 46(4): 777-89.

Barton RA, Whiten A, Strum SC , Byrne RW, Simpson AJ. 1992. Habitat use and resource availability in baboons. Anim Behav 43(5): 831-44.

Bercovitch FB. 1983. Time budgets and consortships in olive baboons (Papio anubis). Folia Primatol 41(3-4): 180-90.

Bercovitch FB. 1987. Reproductive success in male savanna baboons. Behav Ecol Sociobiol 21(3): 163-72.

Bercovitch FB. 1989. Body size, sperm competition, and determinants of reproductive success in male savanna baboons. Evolution 43(7): 1507-21.

Bercovitch FB. 1991. Mate selection, consortship formation, and reproductive tactics in adult female savanna baboons. Primates 32(4): 437-52.

Bercovitch FB, Harding RSO. 1993. Annual birth patterns of savanna baboons (Papio cynocephalus anubis) over a ten-year period at Gilgil, Kenya. Folia Primatol 61(3): 115-22.

Bergman TH, Beehner JC. 2004. Social system of a hybrid baboon group (Papio anubis x P. hamadryas). Int J Primatol 25(6): 1313-30.

Coelho AM. 1985. Baboon dimorphism: growth in weight, length and adiposity from birth to 8 years of age. In: Watts ES, editor. Nonhuman primate models for human growth and development. New York : Alan R. Liss. p 125-59.

Detwiler KM, Burrell AS , Jolly CJ. 2005. Conservation implications of hybridization in African Cercopithecine monkeys. Int J Primatol 26(3): 661-84.

Domb LG, Pagel M. 2001. Sexual swellings advertise female quality in wild baboons. Nature 410(6825): 204-6.

Dunbar RIM, Dunbar EP. 1974. Ecological relations and niche separation between sympatric terrestrial primates in Ethiopia . Folia Primatol 21: 36-60.

Easley SP, Coelho Jr. AM. 1991. Is lipsmacking an indicator of social status in baboons? Folia Primatol 56(4): 190-201.

Eley RM, Strum SC, Muchem G, Reid GDF. 1989. Nutrition, body condition, activity patterns, and parasitism of free-ranging troops of olive baboons (Papio anubis) in Kenya. Am J Primatol 18(3): 209-19.

Fa JE, Ryan SF, Bell DJ. 2005. Hunting vulnerability, ecological characteristics and harvest rates of bushmeat species in afrotropical forests. Biol Conserv 121(2): 167-76.

Farah I, Börjesson A, Kariuki T, Yole D, Suleman M, Hau J, Carlsson HE. 2003. Morbidity and immune response to natural schistosomiasis in baboons (Papio anubis). Parasitol Res 91(4): 344-8.

Forster D, Strum SC. 1994. Sleeping near the enemy: patterns of sexual competition in baboons. In: Roeder JJ, Thierry B, Anderson JR, Herrenschmidt N, editors. Current primatology, Vol. 2. Social development, learning and behaviour. Strasbourg (France): Univ Louis Pasteur. p 19-24.

Forthman Quick DL. 1986. Activity budgets and the consumption of human food in two troops of baboons, Papio anubis, at Gilgil , Kenya. In: Else JG, Lee PC, editors. Primate ecology and conservation, Volume 2. Cambridge (UK): Cambridge Univ Pr. p 221-8.

Gil Burmann C, Peláez F, Zinner D. 2002. The end of the free-ranging baboon group in Cádiz , Spain . Prim Rep 63: 49-54.

Groves C. 2001. Primate taxonomy. Washington DC : Smithsonian Inst Pr. 350 p.

Hamilton III WJ. 1982. Baboon sleeping site preferences and relationships to primate grouping patterns. Am J Primatol 3(1-4): 41-53.

Harding RSO. 1976. Ranging patterns of a troop of baboons (Papio anubis) in Kenya . Folia Primatol 25: 143-85.

Hassan A. 2001. Notes on olive baboons at Lake Manyara National Park . Ecol J 3: 192-5.

Hill CM. 2000. Conflict of interest between people and baboons: crop raiding in Uganda . Int J Primatol 21(2): 299-315.

Hrdy SB. 1974. Male-male competition and infanticide among langurs (Presbytis entellus) of Abu, Rajastan. Folia Primatol 22: 19-58.

Isabirye-Basuta G. 2004. The status and distribution of primates in Mubende-Toro woodlands and forests. Afr J Ecol 42(Suppl 1): 84-6.

Jolly CJ, Phillips-Conroy JE. 2003. Testicular size, mating system, and maturation schedules in wild anubis and hamadryas baboons. Int J Primatol 24(1): 125-42.

Lieberman D, Hall JB, Swaine MD. 1979. Seed dispersal by baboons in the Shai Hills, Ghana . Ecology 60(1): 65-75.

Nagel U. 1973. A comparison of anubis baboons, hamadryas baboons and their hybrids at a species border in Ethiopia . Folia Primatol 19: 104-65.

Nash LT. 1978. The development of the mother-infant relationship in wild baboons (Papio anubis). Anim Behav 26(3): 746-59.

Naughton-Treves L, Treves A, Chapman C, Wrangham R. 1998. Temporal patterns of crop-raiding by primates: linking food availability in croplands and adjacent forest. J Applied Ecol 35(4): 596-606.

Packer C. 1979a. Inter-troop transfer and inbreeding avoidance in Papio anubis. Anim Behav 27(1): 1-36.

Packer C. 1979b. Male dominance and reproductive activity in Papio anubis. Anim Behav 27(1): 37-45.

Packer C. 1980. Male care and exploitation of infants in Papio anubis. Anim Behav 28: 512-20.

Packer C, Pusey AE. 1979. Female aggression and male membership in troops of Japanese macaques and olive baboons. Folia Primatol 31(3): 212-18.

Palombit RA. 2003. Male infanticide in savanna baboons: adaptive significance and intraspecific variation. In: Jones CB, editor. Sexual selection and reproductive competition in primates: new perspectives and directions. Norman (OK): Am Soc Primatol. p 367-411.

Pfeyffers R. 1999-2000. Underwater swimming by baboons Papio anubis in Nigeria . Afr Prim 4(1&2): 72-4.

Phillips-Conroy JE, Jolly CJ, Brett FL. 1991. Characteristics of hamadryas-like male baboons living in anubis baboon troops in the Awash hybrid zone, Ethiopia. Am J Phys Anthro 86(3): 353-68.

Ransom TW. 1981. Beach troop of the Gombe. East Brunswick (NJ): Assoc Univ Pr. 319 p.

Ransom TW, Rowell TE. 1972. Early social development of feral baboons. In: Poirier FE, editor. Primate socialization. New York : Random House. p 105-44.

Ray JC, Sapolsky RM. 1992. Styles of male social behavior and their endocrine correlates among high-ranking wild baboons. Am J Primatol 28(4): 231-50.

Rowe N. 1996. The pictorial guide to the living primates. East Hampton (NY): Pogonias Pr. 263 p.

Rowell TE. 1966. Forest living baboons in Uganda . J Zool 149: 344-65.

Samuels A, Altmann J. 1986. Immigration of a Papio anubis male into a group of Papio cynocephalus baboons and evidence for an anubis-cynocephalus hybrid zone in Amboseli, Kenya . Int J Primatol 7(2): 131-8.

Sapolsky RM. 1986. Endocrine and behavioral correlates of drought in wild olive baboons (Papio anubis). Am J Primatol 11(3): 217-27.

Sapolsky RM. 1996. Why should an aged male baboon ever transfer troops? Am J Primtol 39(3): 149-55.

Sapolsky RM, Else JG. 1987. Bovine tuberculosis in a wild baboon population: epidemiological aspects. J Med Primatol 16(4): 229-35.

Sapolsky RM, Share LJ. 2004 [cited 2005 Oct 5]. A pacific culture among wild baboons: its emergence and transmission. Plos Biol [Internet] 2(4): 534-6. Available from: http://www.plosbiology.org/archive/1545-7885/2/4/pdf/10.1371_journal.pbio.0020106-S.pdf

Sinsin B, Tehou AC, Daouda I, Saidou A. 2002. Abundance and species richness of larger mammals in Pendjari National Park in Benin . Mammalia 66(3): 369-80.

Smith EO, Whitten PL. 1988. Triadic interactions in savanna-dwelling baboons. Int J Primatol 9(5): 409-24.

Smuts BB. 1985. Sex and friendship in baboons. New York: Aldine de Gruyter. 303 p.

Smuts B, Nicolson N. 1989. Reproduction in wild female olive baboons. Am J Primatol 19(4): 229-46.

Smuts BB, Watanabe JM. 1990. Social relationships and ritualized greetings in adult male baboons (Papio cynocephalus anubis). Int J Primatol 11(2): 147-72.

Strum SC. 1981. Processes and products of change: baboon predatory behavior at Gilgil , Kenya. In: Harding RSO, Teleki G, editors. Omnivorous primates: gathering and hunting in human evolution. New York : Columbia Univ Pr. p 255-302.

Strum SC. 1983. Baboon cues for eating meat. J Hum Evol 12(4): 327-36.

Strum SC. 1987. Almost human: a journey into the world of baboons. Chicago (IL): Univ Chicago Pr. 308 p.

Strum SC. 1991. Weight and age in wild olive baboons. Am J Primatol 25(4): 219-37.

Strum SC. 1994. Prospects for management of primate pests. Rev Ecol 49(3): 295-306.

Strum SC, Southwick CH. 1986. Translocation of primates. In: Benirschke K, editor. Primates: the road to self-sustaining populations. New York: Springer-Verlag. p 949-58.

Whiten A, Byrne RW, Barton RA, Waterman PG, Henzi SP. 1991. Dietary and foraging strategies of baboons. Phil Trans R Soc Lond 334(1270): 187-97.

Zinner D, Peláez F, Torkler F. 2001. Distribution and habitat associations of baboons (Papio hamadryas) in central Ethiopia . Int J Primatol 22(3): 397-413.

Content last modified: April 18, 2006

 

VIDEO & WEBCAMS

IMAGES

Papio anubis
Photo: Alain Houle
Papio anubis
Photo: Alain Houle
Papio anubis
Photo: Alain Houle
Papio anubis
Photo: Alain Houle
Papio anubis
Photo: Alain Houle
Papio anubis
Photo: Alain Houle
Papio anubis
Photo: Anne Zeller
Papio anubis
Photo: Anne Zeller
Papio anubis
Photo: Dennis Rasmussen
Papio anubis
Photo: Dennis Rasmussen
Papio anubis
Photo: Dennis Rasmussen
Papio anubis
Photo: Flying Fish Graphics
Papio anubis
Photo: Flying Fish Graphics
Papio anubis
Photo: Flying Fish Graphics
Papio anubis
Photo: Gustl Anzenberger
Papio anubis
Photo: Gustl Anzenberger
Papio anubis
Photo: Gustl Anzenberger
Papio anubis
Photo: Gustl Anzenberger
Papio anubis
Photo: Washington NPRC

Primate Info Net (PIN) is maintained by the Wisconsin National Primate Research Center (WNPRC) at the University of Wisconsin-Madison, with countless grants and contributions from others over time. PIN is an ever-growing community effort: if you’d like to contribute, or have questions, please don’t hesitate to contact us.