Gelada baboon


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Suborder: Haplorrhini
Infraorder: Simiiformes
Superfamily: Cercopithecoidea
Family: Cercopithecidae
Subfamily: Cercopithecinae
Genus: Theropithecus
Species: T. gelada
Subspecies: T. g. gelada, T. g. obscurus

Other names: gelada baboon; gelada (French); gelada (Swedish); T. g. gelada: common gelada, northern gelada, western gelada; T. g. obscurus: dusky gelada, eastern gelada, Heuglin’s gelada, southern gelada.

The gelada is the sole survivor of the genus Theropithecus, which formerly included several extinct species which were widespread and successful, found over much of Africa and into India (see Delson 1993 & Jablonski 1993; Pickford 1993; Dunbar 1998).

Conservation status:  Least concern

Life span: <14 years (wild)
Total population: <250,000
Regions: Ethiopian highlands
Gestation: 6 months
Height: 50 to 75 cm (M & F)
Weight: 18.5 kg (M), 11 kg (F)


Gelada baboon
Theropithecus gelada

Geladas are large, stocky primates with dark brown to buff coarse pelage and with dark brown faces and lighter, pale eyelids. The tail is shorter than the body and head and has a tuft at the end (Napier 1981; Ankel-Simons 2007). The forearms and extremities are almost black (Napier & Napier 1967). In adult males, a long, heavy, cape of hair is present on the back (Napier 1981; Ankel-Simons 2007). Between subspecies, T. g. gelada usually has predominantly pale brown to dark brown pelage, while T. g. obscurus is darker, ranging from dark brown to almost black (Yalden et al. 1977). The face has no hair, and is shorter and higher than in other baboons. In addition, the snout is more chimp-like than baboon-like (Ankel-Simons 2007). Most characteristic of geladas is the hairless hourglass-shaped pink or red area of skin located on the chest (Napier 1981; Ankel-Simons 2007). In females, this skin patch is surrounded by pearl-like knobs of skin. Geladas have pronounced ischial callosities (Ankel-Simons 2007). On average, males are larger than females and marked sexual dimorphism is characteristic of the species, with females averaging around two-thirds the size of males (Krentz 1993; Jolly 2007). Females average around 11 kg (24.3 lb) while males weigh 18.5 kg (40.8 lb) (data compiled by Jolly 2007). Head and body lengths of the sexes combined range between 50 and 75 cm (19.7 and 29.5 in) and the tail is between 30 and 50 cm (11.8 and 19.7in) long (Ankel-Simons 2007). The species has highly opposable index fingers and thumbs, the most so of any of the primates (Napier 1981). In addition, its fingers are short and substantially built, allowing them to be used efficiently for digging (Dunbar 1976). Geladas have specialized dentition adapted for their highly graminivorous diet, which is highly abrasive to teeth (Jablonski 1994).

In captivity, geladas have lived into their thirties but the estimated wild life expectancy is less than 14 years (Dunbar 1980a; Weigl 2005).

Geladas are one of the most terrestrial of the non-human primates, and are best described as nearly completely terrestrial quadrupeds with specialized morphological adaptations for feeding and moving on the ground (Dunbar 1983b; 1986; Krentz 1993). As a result of its adaptations, feeding occurs on the ground, with only extremely rare excursions into bushes to access food (Dunbar 1977b). The typical feeding posture and associated locomotion (shuffle gait) is unique to the gelada, and occurs in a sitting position (Dunbar 1977b; 1983). During this type of feeding locomotion, the animal squats, feeds, and shuffles forward bipedally without changing its posture allowing near-continuous foraging and consumption (Wrangham 1980; Dunbar 1983b). Movement of this type occurs frequently throughout the day but usually only over distances of less than one meter. As a result, due to high proportions of time spent feeding, the bipedal shuffle gait can comprise up to a third of the daily locomotor behavior (Wrangham 1980).


Theropithecus gelada

Geladas are found only in Ethiopia, on the Ethiopian plateau predominantly south of the Tacazze River, north of the Awash River, and east of the Blue Nile River (Dunbar 1993a; Oates 1996). However, a population was found a significant distance from other populations further south along the upper Wabi-Shebeli River, in the Arusi Region (Mori & Belay 1990). In many places, the distribution is discontinuous and the species occurs only very near cliffs and gorges (Dunbar 1993a). Between subspecies, T. g. obscurus is found in the south of the species range, while T. g. gelada is found in the north. They are roughly divided by the gorges of the Belegas and upper Tacazze rivers (Yalden et al. 1977).

The total wild population of gelada baboons is estimated at slightly less than 250,000 individuals (Dunbar 1998).


Geladas are found in open, high plateaus along the gorges and escarpments that dissect them, above 1500 m (4921.3 ft) up to around 4500 m (14763.8 ft) with most populations inhabiting altitudes between 2000 and 3000 m (6561.7 and 9842.5 ft) (Iwamoto & Dunbar 1983; Dunbar 1992; 1993; Iwamoto 1993; Belay & Shotake 1998; Jolly 2007). Gelada habitats are characterized by their proximity to cliffs for sleeping and the use of several different types of relatively treeless and montane grasslands for foraging, habitats that are usually interspersed with bushes, trees and dense thickets (Dunbar 1976; Kawai & Iwamoto 1979; Napier 1981; Iwamoto & Dunbar 1983; Iwamoto 1993; Jolly 2007). Vegetation in study areas usually consists of grasses, herbs, and bush level vegetation. In some habitats, the weather can be harsh, as hailstorms occur regularly in the wet season and frosts are seen in the dry season (Iwamoto & Dunbar 1983). Because certain areas of their plateau habitat are under human cultivation, populations often are marginalized to the areas near the cliffs and sometimes geladas invade the intrusive cropland to forage (Iwamoto 1993). The typical pattern of habitat use is to sleep on cliffs and to climb up to the plateaus for their daily activities, but still remain close to the cliffs (Napier 1981; Iwamoto 1993; Jolly 2007). While usually only cliff faces and nearby grasslands are utilized, when slopes are present in a habitat, they will be used as well (Mori et al. 1999). Gelada habitat is generally cooler and less arid then lowland areas which mitigates the negative effects of the dry season on food availability (Iwamoto 1993).

Gelada baboon
Theropithecus gelada

On the Amhara plateau, the year can be divided into rainy (June-September) and dry seasons with more southern habitats showing a slight second rainy season in March and April (Iwamoto 1993). Annual rainfall in gelada habitats is usually around 120 cm (47.2 in) but usually increases with altitude (Iwamoto & Dunbar 1983; Iwamoto 1993). Monthly average temperatures on the Amhara plateau range from highs around 20°C (68°F ) (March-May) to lows around 15°C (59°F) (July-September) with a general trend towards lower temperatures as the altitude increases (Iwamoto & Dunbar 1983; Iwamoto 1993). Daily however, the temperature may vary by up to 25°C (45°F) and can drop below freezing (Iwamoto & Dunbar 1983).


Geladas are best described as predominantly graminivorous and are genuine grazers with over 90% of the diet being grass blades. There is a shift to flowers and digging for rhizomes and roots and foraging for herbs when the availability or nutritional value of available grasses changes (Dunbar & Dunbar 1974b; Dunbar 1976; 1977; Iwamoto & Dunbar 1983; Dunbar 1984b; Iwamoto 1993; Dunbar 1998). Geladas are the only graminivorous primate and consume foods more akin to those eaten by ungulates, chewing food about as efficiently as zebras (Iwamoto 1979; Dunbar & Bose 1991; Iwamoto 1993). They eat both the leaves and seeds of grasses, in addition to herbs, flowers, small plants, fruits, creepers, bushes, thistles, and insects (Dunbar 1976; 1977; Iwamoto & Dunbar 1983; Iwamoto 1993). Insects are only eaten rarely and then only if they are easily attained (Iwamoto 1993). There is a variable seasonal shift in dry season diet in which fewer grasses are consumed and other food plants, especially herbs, are substituted. Further, when grasses are in seed, proportionally more seeds are consumed and they are preferentially chosen over grass blades when both are available (Dunbar 1976; Iwamoto 1993).

The night is spent on cliff faces, sleeping on ledges (Crook 1966). In the morning around sunrise, the diurnal geladas will leave their sleeping cliffs, ascend to the top of the plateau and immediately commence social activities and feeding (Dunbar & Dunbar 1974b; Dunbar 1977b; Iwamoto 1993). After the morning social interaction, feeding increases in incidence and is the main activity for the rest of the day, sometimes punctuated by travel, until the evening when some social activity is seen again prior to descending to the cliff sleeping sites (Dunbar & Dunbar 1974b; Dunbar 1977b). Between several study sites, the day is usually spent feeding (35.7-62.3%), moving (14.7-20.4%), resting (5.2-26.3%), and in social activities (16.0-20.5%) (Iwamoto & Dunbar 1983). However, at some study locations, feeding may consist of up to 81.6% of the time spent during the day with the remainder of the day spent mostly moving and grooming (Kawai & Iwamoto 1979). The active period is between 11-12 hours and during the dry season, more time is spent feeding (Iwamoto 1993). Most of the distance traveled over the course of the day is due to foraging and as habitat altitude increases, feeding time goes up (Dunbar 1977b; Iwamoto & Dunbar 1977; Dunbar 1992). In general between populations, as feeding goes up, resting decreases, and relative to one another, time spent moving and in social interactions stays about the same (Iwamoto & Dunbar 1983).

Gelada baboon
Theropithecus gelada

Day range varies daily and seasonally but is closely related to group size, with animals ranging between averages of 600-2160 m (1968.5-7086.6 ft) per day with larger groups moving longer distances (Dunbar & Dunbar 1979; Kawai & Iwamoto 1979; Iwamoto & Dunbar 1983). Home ranges vary between about 0.78 and 3.44 km2 (0.3 and 1.3 mi2) and similarly to day range, are related to group size, with larger groups possessing larger home ranges (Iwamoto & Dunbar 1983).

During the rainy season, geladas feed by sitting and foraging with both hands in turn, using their thumb and 1st digit to pick suitably green blades of grass (Crook & Aldrich-Blake 1968; Dunbar 1977b; Iwamoto 1993). The blades are only transferred to the mouth after 10-20 are accumulated in the hand and after several minutes, the gelada will shuffle or walk several meters and continue feeding (Crook & Aldrich-Blake 1968; Dunbar 1977b; Iwamoto 1993). During the dry season, when preferred foods are often under the ground surface, geladas will dig using both hands as shovels (Crook & Aldrich-Blake 1968; Iwamoto 1993).

Other primates with which geladas are often sympatric include baboons (Papio sp.) and vervet monkeys (Chlorocebus aethiops) (Crook & Aldrich-Blake 1968; Dunbar & Dunbar 1979). They are sometimes found in association with baboons but never with vervets. However, because of their specialized diet, they are not in direct food competition with either of these two primate species (Dunbar & Dunbar 1979). On the other hand, also due to their diet, geladas potentially face competition from sympatric, non-primate herbivores, including ibex (Capra walie), klipspringers (Oreotragus oreotragus), bushbucks (Tragelaphus scriptus), duikers (Sylvicapra grimmia) and domesticated horses and cattle (Dunbar 1978a).

Geladas are threatened by several potential and actual predators. These include dogs, jackals, leopards, servals, foxes, hyenas, and lammergeyers (Dunbar & Dunbar 1975; Ohsawa 1979; Iwamoto et al. 1996; Mori et al. 1997). The usual response to predators is to flee to cliff faces, but in some circumstances, males may confront a threat and have even been observed to confront dogs and even mob and surround a leopard (Dunbar & Dunbar 1975; Ohsawa 1979; Iwamoto et al. 1996). In general, predation pressure seems low, likely due to the proximity of humans to many habitats (Iwamoto 1993).

Content last modified: September 3, 2008

Written by Kurt Gron. Reviewed by Robin Dunbar.

Cite this page as:
Gron KJ. 2008 September 3. Primate Factsheets: Gelada baboon (Theropithecus gelada) Taxonomy, Morphology, & Ecology . <>. Accessed 2020 July 29.


The dynamic and complex social system of the gelada baboon is a nested, multi-level hierarchy of social units consisting, in increasing order of size; reproductive units (1-12 adult females, young, 1-4 males) and all-male groups (2-15 males), bands (2-27 reproducive units and several all-male groups), herds (ephemeral accumulations of 2-60 reproductive units, sometimes from different bands), and communities (1-4 bands that overlap extensively) (Crook 1966; Ohsawa 1979; Kawai et al. 1983; Dunbar 1986; 1993; Grüter & Zinner 2004). Herds can be up to around 350 individuals and perhaps as large as 400, but do not last long, are unstable and usually average lower numbers of individuals (Crook 1966; Ohsawa & Kawai 1975; Dunbar 1986; 1993).

Gelada baboon
Theropithecus gelada

The two main levels of organization that comprise the social system are the reproductive unit and the bands that consist of multiple reproductive units (Dunbar 1984b). A result of this is that reproduction occurs at a different level of social complexity (the reproductive unit) than the ecological activities of the species (the band). However, foraging can be coordinated at various levels of gelada social organization (Kawai et al. 1983).

Females are the focus of social relations and interactions in geladas (Dunbar 1986). In reproductive units, if more than one adult male is present, only one is reproductively active to the exclusion of extra-group males as well as other males in the group and thus the reproductive unit is effectively a single-male unit (Dunbar & Dunbar 1975; Ohsawa 1979; Mori et al. 1997). Reproductive units are often stable in composition for longer than six months and are able to withstand disruptions which otherwise might cause social reorganization in other species (Dunbar 1979). Males are usually resident in a reproductive unit for 4-5 years (Dunbar 1986).

Little aggression within a reproductive unit is recorded, with the majority of aggression being directed outward towards non-unit individuals (Dunbar & Dunbar 1975). When it does happen, it is females who initiate agonism with other groups and as the conflict escalates, both males and sometimes many females of the opposing sides get involved. (Dunbar & Dunbar 1975; R.I.M. Dunbar pers. comm). Similarly, in the rare instances where it is seen within a reproductive unit, most aggression is between females (Dunbar & Dunbar 1975). Further, grooming and other social interactions between females usually occurs between pairs which are kin-related and females do not usually interact at all with more than two or three kin females within the reproductive group (Dunbar 1979; 1983; 1986). The restriction in number of individuals with which any individual female socially interacts may be explainable in light of time constraints enforced by large proportions of time spent feeding (Dunbar 1983a). Reproductive units are limited in size however, with periodic fission occurring when they grow too large (Dunbar 1993). Within the reproductive unit, there exists a hierarchy of females, with lower-ranking females attaining less reproductive success and having fewer offspring than higher-ranking individuals (Dunbar 1980b; 1993). Closely related females have similar social status within the hierarchy (Dunbar 1980b). The relationships between females develop and are acted out independently of reproductive interactions with the male (Dunbar 1986). In fact, males are not socially integral to the cohesion of the reproductive unit as a whole (Dunbar 1993).

Females stay in their natal units for life and emigrate only on exceedingly rare occasions (Ohsawa 1979; Dunbar 1993). True transfer between bands is limited to males seeking mating success in a new reproductive unit of their own (Dunbar 1980a). There are two main ways in which the breeding male can change within a reproductive unit; the takeover of a reproductive unit intact or through joining as a subordinate and eventually breaking off with some females as a new reproductive unit (Dunbar 1986). During aggression, a male may use infants (grooming, mounting, handling, carrying, etc.) to his advantage, possibly to enlist help from the mother of the infant in question (Dunbar 1984a). After a takeover by a new male, the former reproductive male can remain in the unit as a non-reproducing subordinate. Further, soon after a takeover, group females acknowledge the new reproductive male by presenting to him (Mori & Dunbar 1985).

Gelada baboon
Theropithecus gelada

All-male groups are led by a single male individual and normally contain one young adult and several sub-adult males, with individuals usually spending 2-4 years after emigration in an all-male group before joining or attempting to join a reproductive unit. In general, interactions between all male groups, other all-male groups, and reproductive units are usually agonistic (Dunbar & Dunbar 1975). There is some indication that all-male groups may function as buffer groups in which males who are not members of a reproductive unit may reside (Mori et al. 2003). Similar to the case of the reproductive unit, the all-male group is also aggressive to non-group individuals but not often amongst itself (Dunbar & Dunbar 1975).

The band and its constituent reproductive units exist within a common home range (Dunbar 1984b). Bands typically break apart every eight or nine years with a new band being formed in a new home range (Dunbar 1980a; 1993). Members of a band are probably highly related to each other (Dunbar 1993). Between units or their leaders comprising a band, there are no status hierarchies (Mori 1979c).

Play among juveniles is curtailed in periods of environmental impoverishment, as is the case during the dry season (Barrett et al. 1992).

In captivity, post-conflict geladas will amicably rejoin the individual toward whom aggression was directed (Swedell 1997).


Most copulations occur during the morning before midday, and when in estrus, a female usually copulates 2-5 times per day (Mori 1979d).

Only the male unit leader copulates with unit females (Mori 1979d). Prior to copulation, the male usually approaches the female, inspects her ano-genital region and chest, and then copulates with her while the female usually solicits copulation, receives or accepts the genital inspection of the male, and then copulates with him (Dunbar 1974c; Bernstein 1975; Mori 1979d). Females usually solicit the majority of copulations, but aside from solicitation, social interest between males and females is generally unchanged during estrus, and similarly, social relations within the reproductive unit remain stable and unchanged during estrus (Dunbar 1978b). The usual female solicitation posture involves the female pointing and raising her posterior towards a male and moving her tail to one side (Bernstein 1975; Dunbar 1978b). Copulations are short in duration, usually lasting only around ten seconds and are normally accompanied by vocalizations. Post-copulation, grooming often occurs (Mori 1979d).

Estrus and hormonal changes in gelada baboon females are externally visible in changes in the physical appearance of the pink-red patches of skin on their chests and abdomen as well as ano-genital regions. The main change is beading, the appearance of so-called beads of skin (fluid filled vesicles) along the periphery of each of the patches of skin which may emit some sort of olfactory signal (Dunbar & Dunbar 1974c; Dunbar 1977a; 1978b; McCann 1995). Changes in color of the patches themselves however, do not correspond with the estrus condition (Dunbar & Dunbar 1974c). However, the color of the chest patches does correspond with age, with younger females having purplish patches which fade to pink in older females (Dunbar 1977a). Also, females emit a specific type of estrus call to inform males of their condition (Moos-Heilen & Sossinka 1990). Mating can occur at any time in the estrus cycle; however copulation frequency increases around ovulation (Dunbar 1984b; McCann 1995). In captivity, the length of the estrus cycle varies greatly, but averages 37.3 days (McCann 1995).

Gelada baboon
Theropithecus gelada

Reproduction occurs throughout the year and the species does not display a discrete reproductive season, however at some study sites there are birth peaks (Mori 1979a; 1979c; Dunbar et al. 2002; Jolly 2007). Females reach puberty at 3 years old, but usually first give birth at around 4 years old and the interbirth interval averages 2.1 years (Dunbar & Dunbar 1975; Dunbar 1984b). Males are capable of reproduction between 4-5 years old, but do not usually father offspring before 8-10 years of age due to social factors (Jolly 2007). The usual pattern for males is to emigrate from the natal group at puberty, spend several years in an all male-group, and then attempt to monopolize a reproductive unit (Dunbar 1993). The gestation length is estimated at around 6 months (Hill 1970; Klecha et al. 1998; Jolly 2007).


Gelada births tend to occur at night but have been observed in the early morning (Dunbar & Dunbar 1974a). At birth, the infant’s eyes are closed, the face is red, and the body is covered with black hair until around three months old (Dunbar & Dunbar 1974a; Mori 1979a; R.I.M. Dunbar pers. comm.). Weight at birth averages 464.0 g (Leutenegger 1973). For some time after birth, the mother remains on the periphery of the reproductive group with other group juveniles and young and adult females showing keen interest in the neonate (Dunbar & Dunbar 1974a; Mori 1979a). This interest is strong and younger females may even try to take a very young infant from its mother (Mori 1979a).

From birth, the infant is carried ventrally, however after 5 weeks old the infant is predominantly carried on the mother’s back, sometimes with its tail entwined with hers (Mori 1979a; Barrett et al. 1995). By 5 months of age, infants are more likely to be moving independently than being carried and by this time, ventral carrying is never seen (Barrett et al. 1995).

The infant first starts trying to move away from its mother at two weeks old (Mori 1979a). Also, sometimes juveniles and infants of neighboring harems in the same herd join into play groups of up to around ten individuals of both sexes. As they approach puberty, males may aggregate into unstable groups that may move independently of reproductive units. Starting around six months old, subordinate group males may help provide care for a specific infant (Mori 1979a).

Infanticide has been observed in the wild and captivity among gelada baboons, and is often perpetrated by immigrant or newly dominant males (Moos et al. 1985; Mori et al. 1997; 2003). Regardless, infant mortality is relatively low, with over 85% of infants living at least until their 4th birthday. Infant mortality is higher in the wet season than during the dry season (Dunbar 1980a).


Gelada baboon
Theropithecus gelada

Adult geladas have a diverse repertoire of over thirty discrete vocalizations, including contact, reassurance, appeasement, solicitation, ambivalence and aggressive-defensive vocalizations (Kawai 1979; Aich et al. 1990). Vocalizations are often combined together into sequences. Contact calling may be continuous and the common calling and replying between individuals may have important social functions. When vocalizations are directed at the members of a different reproductive unit, they are usually threatening (Kawai 1979). In captivity, vocalizations can be divided into four discrete groups, harmonic calls (friendly and positive situations), aspirated calls (agonistic and threatening situations), kecker calls (submissive situations) and scream calls (show submission to a superordinate). Calls are to an extent related to the social status of a gelada, with certain calls restricted to those of a particular social status. Particular calls are always uttered towards dominant individuals. In addition, if social status changes, the qualitative and quantitative aspects of vocalizations change (Aich et al. 1990). In captivity, higher-ranking individuals of both sexes exhibit higher calling rates (Aich et al. 1987).

In captivity, female geladas have specific estrus calls which inform males of their condition. Further, captive experiments have shown that unit males are able to differentiate females from one another exclusively based on their calls (Moos-Heilen & Sossinka 1990).

Types of threatening or agonistic gestures include lip rolls (in which the gums and teeth are exposed by flipping the upper lip inside out over the nostrils) and the raising of the eyelids (by pulling back the scalp to show the pale eyelids) (Mori 1979b; Napier 1981; Aich et al. 1990). Submission is indicated by fleeing or presenting (Aich et al. 1990).

It is suggested that the beads of skin (fluid-filled vesicles) which appear on females during estrus may function in olfactory communication (Dunbar & Dunbar 1979c).

Content last modified: September 3, 2008

Written by Kurt Gron. Reviewed by Robin Dunbar.

Cite this page as:
Gron KJ. 2008 September 3. Primate Factsheets: Gelada baboon (Theropithecus gelada) Behavior . <>. Accessed 2020 July 29.



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

Gelada baboon
Theropithecus gelada

Within Ethiopia, geladas are protected in the Simien Mountains National Park, a UNESCO World Heritage Site, and hunting of the species is forbidden within its confines (Dunbar 1993a; Oates 1996; For the most part however, this park exists more for the conservation of the extremely rare Walia ibex (Capra walie) than specifically for the gelada (Dunbar 1993c). However, human densities on the Ethiopian plateau are among the highest in Africa and as a result there is a high potential for conflict over habitat (Dunbar 1993a).


Threat: Human-Induced Habitat Loss and Degradation

Threatened and actual habitat loss seriously endangers the gelada. A main threat is the use of its preferred habitat for agriculture. So extensive is agricultural production that in some areas were farmland is at a premium, slopes that are too sleep for plowing are cultivated by hand. As preferred habitat is destroyed, geladas will likely have to move to more marginal areas, reducing their population densities (Dunbar 1977c).

Geladas are also potentially threatened by global climate change predominantly due to their attitudinally restricted habitat. If global temperature rises, the altitude at which the montane grasses grow that provide the gelada diet would increase and eventually gelada habitat would cease to exist. As an example, if global temperature were to rise 5°C (9°F), gelada populations would be reduced by two-thirds, due to a reduction in extent of habitat (Dunbar 1998).

Threat: Invasive Alien Species

The deforestation of certain areas near gelada habitat has indirectly threatened the species. This is due to the replanting of quick-growing, non-native Eucalyptus globules trees, which do not retain soil as well as native species, inhibit the growth of grass, and actually increase topsoil loss (Dunbar 1977c).

Threat: Harvesting (hunting/gathering)

In past centuries and even recently, male geladas were killed by indigenous pastoral groups to procure their manes for ceremonial headdresses. These culls remove only adult males from the population, altering species reproductive and social dynamics (Dunbar 1977c; 1993a). Hunting of geladas for bushmeat is rare due to orthodox religious beliefs of many local groups living in proximity to geladas (Hunter 2007).

Threat: Persecution

Owing to their specialized diet, geladas do not usually crop-raid and this fact may help reduce persecution by humans (Dunbar 1993a). However, in times of drought or other exceptional circumstances, geladas will raid cropland if necessary, especially around harvest time (Dunbar 1977c). In most cases however, if confronted by farmers, geladas will retreat and will not continue feeding, perhaps lessening conflict (Dunbar 1977c).




Content last modified: September 3, 2008

Written by Kurt Gron. Reviewed by Robin Dunbar.

Cite this page as:
Gron KJ. 2008 September 3. Primate Factsheets: Gelada baboon (Theropithecus gelada) Conservation . <>. Accessed 2020 July 29.


The following references were used in the writing of this factsheet. To find current references for Theropithecus gelada, search PrimateLit.


Aich H, Zimmermann E, Rahmann H. 1987. Social position reflected by contact call emission in gelada baboons (Theropithecus gelada). Z Saugetierkunde 52(1):58-60.

Aich H, Moos-Heilen R, Zimmermann E. 1990. Vocalizations of adult gelada baboons (Theropithecus gelada): acoustic structure and behavioural context. Folia Primatol 55(3-4):109-32.

Ankel-Simons F. 2007. Primate Anatomy: an introduction, 3rd Edition. San Diego: Elsevier Acad Pr. 724 p.

Barrett L, Dunbar RIM, Dunbar P. 1992. Environmental influences on play behaviour in immature gelada baboons. Anim Behav 44(1):111-5.

Barrett L, Dunbar RIM, Dunbar P. 1995. Mother-infant contact as contingent behaviour in gelada baboons. Anim Behav 49(3):805-10.

Belay G, Shotake T. 1998. Blood protein variation of a new population of gelada baboons (Theropithecus gelada), in the southern rift valley, Arsi Region, Ethiopia. Primates 39(2):183-98.

Bernstein IS. 1975. Activity patterns in a gelada monkey group. Folia Primatol 23:50-71.

Crook JH, Aldrich-Blake P. 1968. Ecological and behavioural contrast between sympatric ground dwelling primates in Ethiopia. Folia Primatol 8:192-227.

Crook JH. 1966. Gelada baboon herd structure and movement: a comparative report. Symp Zool Soc Lond 18:237-58.

Delson E. 1993. Theropithecus fossils from Africa and India and the taxonomy of the genus. In: Jablonski NG, editor. Theropithecus: the rise and fall of a primate genus. Cambridge: Cambridge U Pr. p 157-89.

Dunbar RIM, Bose U. 1991. Adaptation to grass-eating in gelada baboons. Primates 32(1):1-7.

Dunbar RIM. 1977a. Age-dependent changes in sexual skin colour and associated phenomena of female gelada baboons. J Hum Evol 6:667-72.

Dunbar RIM. 1993a. Appendix II: conservation status of the gelada. In: Jablonski NG, editor. Theropithecus: the rise and fall of a primate genus. Cambridge: Cambridge U Pr. p 527-31..

Dunbar RIM. 1976. Australopithecine diet based on a baboon analogy. J Hum Evol 5:161-7.

Dunbar RIM, Dunbar P. 1974a. Behaviour related to birth in wild gelada baboons (Theropithecus gelada). Behaviour 50(1-2):185-91.

Dunbar RIM. 1978a. Competition and niche separation in a high altitude herbivore community in Ethiopia. E Afr Wildl J 16:183-99.

Dunbar RIM. 1980a. Demographic and life history variables of a population of gelada baboons (Theropithecus gelada). J Anim Ecol 49(2):485-506.

Dunbar RIM. 1980b. Determinants and evolutionary consequences of dominance among female gelada baboons. Behav Ecol Sociobiol 7:253-65.

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

Dunbar RIM. 1977b. Feeding ecology of gelada baboons: a preliminary report. In: Clutton-Brock TH, editor. Primate ecology: studies of feeding and ranging behaviour in lemurs, monkeys and apes. London: Academic Pr. p 251-73.

Dunbar RIM, Hannah-Stewart L, Dunbar P. 2002. Forage quality and the costs of lactation for female gelada baboons. Anim Behav 64(5):801-5.

Dunbar RIM. 1977c. The gelada baboon: status and conservation. In: Rainier III (Grimaldi) Prince of Monaco, Bourne GH, editors. Primate conservation. New York: Academic Pr. p 363-83.

Dunbar RIM. 1998. Impact of global warming on the distribution and survival of the gelada baboon: a modeling approach. Glob Chan Biol 4(3):293-304.

Dunbar RIM. 1984a. Infant-use by male gelada in agonistic contexts: agonistic buffering, progeny protection or soliciting support? Primates 25(1):28-35.

Dunbar RIM. 1992. A model of the gelada socio-ecological system. Primates 33(1):69-83.

Dunbar RIM, Dunbar P. 1974c. The reproductive cycle of the gelada baboon. Anim Behav 22:203-10.

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Content last modified: September 3, 2008




Theropithecus gelada
Photo: Irwin S. Bernstein
Theropithecus gelada
Photo: Irwin S. Bernstein
Theropithecus gelada
Photo: Irwin S. Bernstein
Theropithecus gelada
Photo: Irwin S. Bernstein
Theropithecus gelada
Photo: J. Stephen Gartlan
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Photo: Kalle Stolt
Theropithecus gelada
Photo: Kalle Stolt
Theropithecus gelada
Photo: Kalle Stolt
Theropithecus gelada
Photo: Kalle Stolt
Theropithecus gelada
Photo: Peter Fashing
Theropithecus gelada
Photo: Peter Fashing
Theropithecus gelada
Photo: Peter Fashing
Theropithecus gelada
Photo: Peter Fashing


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