PRIMATES

Full screen Primates Id code: amd082

Cercopithecidae
Theropithecus gelada

(Rüppell, 1835)

(Eng) Gelada baboon

(Fre) Gelada

Taxonomic notes

Two subspecies have been described: T. g. gelada and T. g. obscurus. The population inhabiting the Wabi-Shebeli gorges might represent a distinct form (Kingdon, 1997; Iwamoto, 1993).

IUCN threat category

Lower Risk, but near threatened (LR: nt).

Available information

The species has been widely studied and information is available on the main aspects of its ecology. Details on evolutionary history, anatomy, ecology and behaviour of the species are treated in a recent monography (Jablonski, 1993). Crook & Aldrich-Blake (1968) and Dunbar & Dunbar (1974) investigated the niche separation and competition among coexisting primate species, including this baboon; the authors also report information on the main aspects of the species’ ecology. Niche separation and coexistence among herbivore communities of the Simen Mountains are discussed in Dunbar (1978), while some information on habitat use and preferences in the Simen Mountains is given by Nievergelt (1981). Notes on its feeding habits and foraging behaviour are found in Dunbar (1977a). Data on its occurrence along the Wabi-Shebeli River are reported by Mori & Belay (1990). The species’ overall distribution is analysed in Hall (1966), Yalden et al. (1977, 1996), Yalden & Largen (1992). General information on the species’ ecology is reported by several authors (Bourlière, 1985; Clutton-Brock, 1977; Dunbar, 1988; Eisenberg et al., 1979; Kingdon, 1997; Stuart & Stuart, 1997). Status, threats, and conservation issues are discussed in Dunbar (1977b), Lee et al. (1988) and Oates (1996); the authors mentioned also report on the ecology of the species, particularly the habitat in which it occurs.

Known extent of occurrence

The gelada is endemic of the Ethiopian highlands, the Blue Nile Gorge and the upper Wabi-Shebeli valley which mark, respectively, the western and south-eastern boundaries of its range. Its distribution is closely related to the escarpments and gorge systems of the provinces of Tigre, Wollo, Shoa and Begemdir and a small population also inhabits the Wabi-Shebeli gorge (Yalden & Largen, 1992). Fig. 2.3.32.a, acquired from Kingdon (1997) and revised on the basis of available location records, summarises the present distribution of T. gelada.

Categorical-discrete (CD) distribution model

This species prefers montane grasslands and shrublands between 1500 and 4000 m altitude, it also occurs in cultivated land, while it seldom enters forested areas (Crook & Aldrich-Blake, 1968; Iwamoto, 1993; Yalden & Largen, 1992; Lee et al., 1988; Dunbar, 1977b).

Based on these environmental preferences, the following scores were assigned (Fig. 2.3.32.b) (2.3.32.a):

Score
1	Grasslands and grassland mosaics above 1500 m altitude.
2	Bushlands; forests and croplands above 1500 m altitude.
3	Woodlands and all vegetation types below 1500 m altitude.

suitable		moderately suitable		unsuitable		Total
km²	%	km²	%	km²	%	km²	%
51 320	34	82 935	55	15 980	11	150 235	100

Tab 2.3.32.a: Cumulative size (km²) of areas pertaining to each environmental suitability class within the Extent of Occurrence.

	Number Patches (NP)	Mean Patch Size (MPS) km²	Patch Size SD (PSSD) km²	Largest Patch Index (LPI) %	Mean Shape Index (MSI)	Area-Weighted Mean Shape Index (AWMSI)
suitable	114	445	2 599	20.58	1.5	6.5
moderately suitable	55	1 525	10 771	59.95	1.38	14.73
Total AO	9	14 953	41 710	98.77	1.65	4.33

Tab 2.3.32.b: Area of Occupancy fragmentation indexes.

Probabilistic-continuous (PC) distribution model

The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 2.3.32.c.

Validation

No occurrence of the species within the four sample areas.

Comments and conservation issues

This species has a relatively small but largely suitable EO (34% suitable and 55% moderately suitable), in which the AO appears to be only slightly fragmented (LPI = 98.77% and the AWMSI is moderate when both suitable and moderately suitable areas are considered). However, within the EO the species is often hunted and compressed by expanding agriculture and its presence is discontinuous. The smaller range in the south appears to be of low suitability and this adds to the vulnerability due to its isolation. The species is classified as Lower Risk (near threatened) by the IUCN threat category system and is hardly protected by any parks or reserves: only the small Simen National Park provides limited protection.

SUITABILITY CLASS	inside	outside	Total
suitable	0.14	34.02	34.16
moderately suitable	0.16	55.04	55.20
unsuitable	0	10.64	10.64
Total	0.30	99.70	100

Tab 2.3.32.c: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas.

References

Bourlière F. (1985). Primate communities: their structure and role in tropical ecosystems. Int J. Primatol.: 6, 1-26.

Clutton-Brock T.H. (Ed.) (1977). Primate Ecology: Studies of Feeding and Ranging Behaviour in Lemurs, Monkeys and Apes. Academic Press, London and New York.

Crook J.H., Aldrich-Blake F.P.G. (1968). Ecological and behavioural contrasts between sympatric ground dwelling primates in Ethiopia. Folia Primatol.: 8, 192-227.

Dunbar R.I.M. (1977a). Feeding Ecology of Gelada Baboons: a Preliminary report. In: Clutton-Brock T.H. (Ed.). Primate Ecology: Studies of Feeding and Ranging Behaviour in Lemurs, Monkeys and Apes. Academic Press, London and New York: chap. 9, 251-273.

Dunbar R.I.M. (1977b). The Gelada Baboon: status and conservation. In: Bourne G.H. (Ed.). Primate Conservation. Academic Press, London and New York: chap. 11, 363-383.

Dunbar R.I.M. (1978). Competition and niche separation in a high altitude herbivore community in Ethiopia. E. Afr. Wildl. J.: 16, 183-199.

Dunbar R.I.M. (Ed.) (1988). Primate Social Systems. Croom Helm Publishers Ltd, London.

Dunbar R.I.M., Dunbar E.P. (1974). Ecological relations and niche separation between sympatric terrestrial primates in Ethiopia. Folia Primatol.: 21, 36-60.

Eisenberg J.F., Muckenhirn N., Rudran R. (1979). The relations between ecology and social structure in primates. [reprinted from Science (1972), 176: 863-874]. In: Sussman R.W. (Ed.). Primate Ecology. Problem-oriented field studies. Wiley, Chichester & New York. chap. 23: 455-484.

Hall K.R.L. (1966). Distributions and adaptations of baboons. Symp.Zool. Soc. Lond.Oxford: Clarendon Press.: 17, 49-73.

Iwamoto T. (1993). The ecology of Theropithecus gelada. In: Jablonski N.G. (Ed.). Theropithecus. The Rise and Fall of a Primate Genus. Cambridge University Press, Cambridge, U.K: chap. 16:441-452.

Jablonski N.G. (1993) (Ed.). Theropithecus. The rise and Fall of a Primate Genus. Cambridge University Press, Cambridge, U.K: chap. 16:441-452.

Kingdon J. (1997). The Kingdon field guide to African Mammals. Academic Press, London and New York: Natural World.

Lee P.C., Thornback J., Bennet E.L. (1988). Threatened Primates of Africa. IUCN, Gland - Switzerland and Cambridge, UK.

Mori A., Belay G. (1990). The distribution of baboon species and a new population of gelada baboons along the Wabi-Shebeli River, Ethiopia. Primates: 31(4), 495-508.

Nievergelt B. (1981). Ibexes in an African Environment. Ecology and social system of the Walia Ibex in the Siemen Mountains, Ethiopia. Springer Verlag: Berlin and New York Ecology Studies.

Oates J.F. (1996). African Primates Status Survey and Conservation Action plan. IUCN/SSC Primate Specialist Group.

Stuart C., Stuart T. (1997). Field guide to the larger mammals of Africa. Struik Publishers.

Yalden D.W., Largen M.J. (1992). The endemic mammals of Ethiopia. Mammal Rev.: 22 (3/4), 115-150.

Yalden D.W., Largen M.J., Kock D. (1977). Catalogue of the mammals of Ethiopia 3. Primates. Monitore Zoologico Italiano: suppl. IX, 1-52.

Yalden D.W., Largen M.J., Kock D., Hillman J.C. (1996). Catalogue of the mammals of Ethiopia and Eritrea. 7. Revised checklist, zoogeography and conservation. Tropical Zoology: 9, 73-164.