Primates Id code: amd002Hominidae Pan troglodytes (Blumenbach, 1775) (Eng) Chimpanzee (Fre) Chimpanzé Taxonomic notes Pan includes two extant species: P. troglodytes and P. paniscus. There is considerable confusion with regard to the number of geographic races that warrant subspecific recognition (Jones et al., 1996). According to Oates (1996) three subspecies are widely recognised, namely P. t. schweinfurthi (Eastern chimpanzee) between Tanzania and former Zaire; P. t. troglodytes between former Zaire and Nigeria and P. t. verus (Western chimpanzee) between Togo and Senegal. IUCN threat category Listed as Endangered (EN: criteria A2cd) both as a species and as P. t. troglodytes; Endangered (EN: criteria A1cd+2cd) as P. t. schweinfurthi and as P. t. verus. Available information Chimpanzee is among the most studied mammal species in the world, and literature available is very conspicuous. Only a selection of the references available is reported here. Comprehensive sources of information of the ecology of this species are Goodall (1990), Jones et al. (1996), and Heltne & Marquardt (1989). A review of the literature available on this species up to 1973 is found in Balwin & Teleki (1973). Feeding habits and social behaviour were investigated in the Kigoma and Mpanda District (Western Tanzania) by Suzuki (1969); the author also gives a quite detailed description of the habitat in which the species was observed. This is one of the few studies on this species in savanna woodland. Boesch (1994), Boesch & Boesch (1989) and Wrangham & van Z. B. Riss (1990) focused on its diet and predatory behaviour. Population numbers, structure, and dynamics are analysed in Hashimoto (1995) and Sugiyama (1984), who conducted their study in the Kalinzu Forest (Uganda) and at Bossou (Guinea) respectively. A study on the use of first growth and secondary growth forest was carried out by Fimbel (1994) at Tiwai (Sierra Leone). Coexistence and niche separation with gorillas are briefly discussed in Yamagiwa (1995), who did research on those species in the Kahuzi-Biega National Park (former Zaire), and in Tutin & Fernandez (1985). The most studied aspect of the species’ ecology is its behaviour and literature available on the matter is vast. A quite complete description of its social behaviour is found in Dunbar (1988). The use of hands and tools is analysed in Boesch & Boesch (1990) and Marchant & McGrew (1996), who both investigated the species at Gombe National Park (Tanzania). Boesch & Boesch (1990) also report some data from Tai National Park (Ivory Coast). Vocalisation and differences between sexes are described in Mitani & Gros-Louis (1995). Goodall (1979) reports accurate data on cannibalistic behaviour observed at Gombe (Tanzania). The species’ distribution and population numbers are constantly monitored, and updated data are reported in Oates (1996). Further information on its occurrence and status are available for Gabon (Blom et al., 1992), Ghana (Booth, 1979), Ivory Coast (Marchesi et al., 1995), Rwanda (Monfort, 1992), Tanzania (Goodall, 1989), Uganda (Huggard, 1994; Plumptre & Reynolds, 1996), Nigeria (Osemeobo, 1988), part of Cameroon and Congo (Mitani, 1990) and former Zaire (Colyn, 1987; Verschuren, 1975; Rahm & Christiaensen, 1966). The authors mentioned above also give some information on the habitat in which the species is found. Coe (1975) reports data on its occurrence on Mount Nimba (Liberia) and includes a detailed description of the vegetation of the area surveyed. General information on the species’ ecology and distribution is found in Clutton-Brock (1977), Kingdon (1997), Tuttle (1990), Stuart & Stuart (1997), and Wrangham & van Z. B. Riss (1990). Status, threats and conservation issues are discussed in Bearder (1991), Mittermeier (1986), Oates (1996), Struhsaker (1981), and Teleki (1988). Known extent of occurrence The distribution map was obtained from Oates (1996) and adjusted to match the river network using Kingdon (1997). The species is discontinuously distributed in the west African forests and better represented in Central Africa, from south Cameroon to eastern former Zaire, north of the Zaire River, and eastward to Uganda. Separate populations also occur in southern Sudan and western Tanzania (see Fig. 2.4.3.a).  Categorical-discrete (CD) distribution model This species is mainly found in forest and forest galleries; it also occurs in moist woodland savanna (Teleki, 1988; Kingdon, 1997; Stuart & Stuart, 1997; Haltenorth & Diller, 1980). Based on these environmental preferences, the following scores were assigned (Fig. 2.4.3.b) (Tab. 2.4.3.a):
Tab 2.4.3.a: Cumulative size (km2) of areas pertaining to each environmental suitability class within the Extent of Occurrence.
Tab 2.4.3.b: Area of Occupancy fragmentation indexes. Probabilistic-continuous (PC) distribution model The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 2.4.3.c. Validation
Tab 2.4.3.c: Categorical-discrete (CD) distribution model validation parameters. Comments and conservation issues The overall EO of the species, even though divided into several parts, is still quite large (1.85 million km2). It is also mostly suitable, confirming that the species is affected more by direct human persecution than habitat destruction. Being a large and charismatic species, its EO is drawn with greater accuracy and the fragmentation of the EO in Fig. 2a shows the level of knowledge of the species’ distribution. Also the Index of Accordance which scores as high as 82.76%, shows that the available information on the species’ ecology is quite adequate for deriving the CD model. Within the EO, the species occurs with patchy distribution possibly due to human pressure: this is the case of Guinea and most of the small areas in western Africa, as well as the eastern parts of the range, where interspersion with less suitable areas is more frequent (see both models). Fragmentation of suitable areas is more severe there, reducing the size of potentially suitable zones for the species. The stronghold for the species is the central large patch of suitable areas. About 6.5% of the total AO is included in the existing protected areas throughout the EO: this percentage is certainly not distributed in a uniform manner and it will be useful to analyse the way they cover the various EO fragments. The species as a whole is classified as Endangered, although some local populations are obviously in much worse conditions: as a general guideline, conservation should be focused where there is the greatest probability of contributing the largest possible benefit to the species and not where the last animals of an isolated patch one to be saved.
Fig. 2.4.3.d: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas. References Balwin L.A., Teleki G. (1973). Field research on Chimpanzees and Gorillas: An historical, geographical, and bibliographical listing. Primates: 14, 315-330. Bearder S.K. (1991). Primate conservation and wildlife management. In: Box H.O. (Ed.). Primate responses to environmental change. Chapman & Hall, London: chap. 11: 199-211. Blom A., Alers M.P.T., Feistner A.T.C., Barnes R.F.W., Barnes K.L. (1992). Primates in Gabon - current status and distribution. Oryx: 26(4), 223-234. Boesch C. (1994). Chimpanzees-red colobus monkeys: A predator prey system. Anim. Behav.: 47(5), 1135-1148. Boesch C., Boesch H. (1989). Hunting behaviour of wild chimpanzees in the Tai National Park, Ivory Coast. Am. J. Phys. Anthrop: 78(4), 547-574. Boesch C., Boesch H. (1990). Tool use and tools making in wild chimpanzees. Folia Primatol.: 54, 86-99. Booth A.H. (1979). The distribution of primates in the Gold Coast. In: Sussman R.W. (Ed.). Primate Ecology. Problem-oriented field studies. Wiley, Chichester & New York: chap. 7: 139-154. 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. Coe M.J. (1975). Mammalian ecological studies on Mount Nimba, Liberia. Mammalia: 39, 523-581. Colyn M.M. (1987). Les primates de la foret ombrophile de la Cuvette du Zaire: interprétations zoogéographique des modèles de distribution. Rev. Zool. Africaine: 101, 183-196. Dunbar R.I.M. (Ed.) (1988). Primate Social Systems. Croom Helm Publishers Ltd, London. Fimbel C. (1994). The relative use of abandoned farm clearings and old forest habitats by primates and a forest antelope at Tiwai, Sierra Leone, West Africa. Biological Conservation: 70, 277-286. Goodall A. (1979). Life and death at Gombe. Nat. Geogr.: 155, 592-621. Goodall J. (1989). Area status report: Tanzania. In: Heltne P.G., Marquardt L.A. (Eds). Understanding Chimpanzees. Harvard University Press: Cambridge, U.K: pp 360-362. Goodall J. (1990). Through a window. 30 years with the Chimpanzees of Gombe. Weidenfeld and Nicolson, London. Haltenorth T., Diller H. (1980). A field guide to the mammals of Africa, including Madagascar. Collins, London. Hashimoto C. (1995). Population census of the chimpanzees in the Kalinnzu Forest, Uganda: comparison between methods with nest counts. Primates: 36(4), 477-488. Heltne P.G., Marquardt L.A. (Eds) (1989). Understanding Chimpanzees. Harvard University Press: Cambridge, U.K. Huggard D.J. (1994). A linear programming model of herbivore foraging: imprecise, yet successful?. Oecologia (Berlin): 100, 470-474. Jones C.L., Jones C.A., Jones J.K., Wilson D.E. (1996). Pan troglodytes. Mammalian Species: 529, 1-9. Kingdon J. (1997). The Kingdon field guide to African Mammals. Academic Press, London and New York: Natural World. Marchant L.F., McGrew W.C. (1996). Laterality of limb function in wild chimpanzees of Gombe National Park: comprehensive study of spontaneous activities. J.Hum.Evol.: 30(5), 427-443. Marchesi P., Marchesi N., Fruth B., Boesch C. (1995). Census and distribution of chimpanzees in Cote D'Ivorie. Primates: 36(4), 591-607. Mitani J.C., Gros-Louis J. (1995). Species and sex differences in the screams of chimpanzees and bonobos. Int.J. Primatol.: 16(3), 393-411. Mitani M. (1990). A note on the present situation of the primates fauna found from South-eastern Cameroon to Northern Congo. Primates: 31(4), 625-634. Mittermeier R.A. (1986). A global overview of primate conservation. In: Else J.G., Lee P.C. (Eds). Primate ecology and conservation. Selected Proceedings of the 10th Congress Int. Primatological Society, Nairobi, Kenya (July 1984). Cambridge University Press, Cambridge, U.K: chap. VI.7, 325-341. Monfort A. (1992). Première liste commentée des mammifères du Rwanda. Rev. Zool. Africaine: 106 (2), 141-151. Oates J.F. (1996). African Primates Status Survey and Conservation Action plan. IUCN/SSC Primate Specialist Group. Osemeobo G.J. (1988). Animal wildlife conservation under multiple land-use systems in Nigeria. Environ. Conserv.: 15(3), 239-249. Plumptre A.J., Reynolds V. (1996). Censusing chimpanzees in the Budongo Forest, Uganda. Int. J. Primatol.: 17(1), 85-100. Rahm U., Christiaensen A. (1966). Les mammiferès de l'Ile Idjwi (Lac Kivu, Congo). Les mammifères de la foret equatoriale de l'est du Congo. Ann. Mus. Roy. Afr. Cent.: n° 149. Struhsaker T.T. (1981). Forest and primate conservation in East Africa. Afr. J. Ecol.: 19, 99-114. Stuart C., Stuart T. (1997). Field guide to the larger mammals of Africa. Struik Publishers. Sugiyama Y. (1984). Population dynamics of wild Chimpanzees at Bossou, Guinea, between 1976-1983. Primates: 25(4), 391-400. Suzuki A. (1969). An ecological study of chimpanzees living in savanna woodland. Primates: 10, 103-148. Teleki G. (1988). Population status of wild chimpanzees (Pan troglodytes) and threats to survival. In: Heltne P.G., Marquardt L.A. (Eds). Understanding Chimpanzees. Harvard University Press: Cambridge, U.K: pp 312-353. Tutin C.E.G., Fernandez M. (1985). Foods consumed by sympatric populations of Gorilla g. gorilla and Pan t. troglodytes in Gabon: some preliminary data. Int J. Primatol.: 6(1), 27-. Tuttle R.H. (1990). Apes of the World. American Scientist: 78 (2), 115-125. Verschuren J. (1975). Wildlife in Zaire. Oryx: 13 (2), 149-163. Wrangham R.W., van Z. B. Riss E. (1990). Rates of predation on mammals by Gombe chimpanzees, 1972-1975. Primates: 31, 157-170. Yamagiwa J. (1995). Sympatry of gorillas and chimpanzees in Eastern Zaire. [Abstract from 1995 Spring meeting Primate Society of Great Britain, Univ of Edinburgh; April, 95]. Folia Primatol.: 64, 105.
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