Primates Id code: amd072Cercopithecidae Cercopithecus neglectus Schlegel, 1876 (Eng) De Brazza's guenon (Fre) Cercopithèque de Brazza Taxonomic notes No significant taxonomic notes. IUCN threat category Not listed. Available information The species' ecology has been studied mainly in former Zaire and in Gabon. Habitat use and preferences, population density, and interspecific relationships with coexisting primates have been investigated in the Lomako Forest (former Zaire) by McGraw (1994). Notes on the species' ecology are also available from Maté et al. (1995), who did research on the species in the Kikofe-Ikomaloki Region (former Zaire). The species has been intensely studied in northeast Gabon, where authors focused mainly on its feeding habits and behavioural aspects of its ecology (Gautier-Hion, 1988; Gautier-Hion & Gautier, 1988; Gautier-Hion et al., 1980; Loireau & Gautier-Hion, 1988). Notes on the species' ecology and occurrence in the Kakamega and Kisere forests (Kenya) are reported in Muriuki & Tsingalia (1990). Data on the species' presence and some information on its ecology are available for part of Cameroon and Congo (Mitani, 1990; Usongo & Fimbel, 1995), former Zaire (Colyn, 1987, 1988), Gabon (Blom et al., 1992), Ethiopia (Yalden et al., 1977; Yalden et al., 1996), and Angola (Feiler, 1990). The species' overall distribution is described in Lernould (1988). General information on the ecology of the species is found in Bourlière (1985) and Kingdon (1997). Status, threats, and conservation issues are discussed in Oates (1996). Known extent of occurrence 
C. neglectus occurs along the Zaire basin in northeast Angola, Cameroon, C.A.R., Congo, Eq. Guinea, Gabon, former Zaire; two isolated populations also exist between south Sudan and southwest Ethiopia and along the Uganda-Kenya boundary. The species' distribution map (Fig. 2.3.16.a) was obtained from Lernould (1988) and updated following the river network to adjust for water course limits (such as northwards of the Sanaga River). The range was finally revised using more recent and reliable source, such as Oates (1996) and Muriuki & Tsingalia (1990). Categorical-discrete (CD) distribution model This species occurs in swampy forest and generally in riverine forest (Bourlière, 1985; McGraw, 1994; Muriuki & Tsingalia, 1990; Kingdon, 1997). Based on these environmental preferences, the following scores were assigned (Fig. 2.3.16.b) (Tab. 2.3.16.a):
Tab 2.3.16.a: Cumulative size (km2) of areas pertaining to each environmental suitability class within the Extent of Occurrence.
Tab 2.3.16.b: Area of Occupancy fragmentation indexes. Probabilistic-continuous (PC) distribution model The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 2.3.16.c. Validation
Tab 2.3.16.c: Categorical-discrete (CD) distribution model validation parameters. Comments and conservation issues The CD model is amply supported by the validation parameters (Index of Accordance 70.37%) and shows that moderately suitable areas account for more than 50% of the total EO and contribute to making the EO largely suitable to the species. Unsuitable areas appear more frequent in southern former Zaire (CD model) and eastern former Zaire (PC model). The two EO fragments in Kenya-Uganda and Ethiopia are shown by both models as very dishomogeneous in terms of suitability. The overall fragmentation is greatly reduced if the moderately suitable areas are also considered, but the suitable areas seem to have a large continuous patch in central former Zaire. The two classes of suitability appear to be highly interspersed as shown by the high values of the AWMSI. Only 5.3% of the total AO is included in existing protected areas.
Tab 2.3.16.d: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas. References 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. Bourlière F. (1985). Primate communities: their structure and role in tropical ecosystems. Int J. Primatol.: 6, 1-26. 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. Colyn M.M. (1988). Distribution of guenons in the Zaire-Lualaba-Lomani river system. In: Gautier-Hion A., Bourlière F., Gautier J., Kingdon J. (Eds). A Primate Radiation: Evolutionary Biology of the African Guenons. Cambridge University Press, New York: pp 104-124. Feiler A. (1990). Distribution of mammals in Angola and notes on biogeography. Vertebrates in the tropics (Peters, G & R Hutter, eds). Museum Alexander Koenig, Bonn.: 221-236. Gautier-Hion A. (1988). The diet and dietary habits of forest guenon. In: Gautier-Hion A., Bourlière F., Gautier J., Kingdon J. (Eds). A Primate Radiation: Evolutionary Biology of the African Guenons. Cambridge University Press, New York: pp 257-283. Gautier-Hion A., Emmons L.H., Dubost G. (1980). A comparison of the diets of three major groups of primary consumers of Gabon (primates, squirrels and ruminants). Oecologia (Berlin): 45, 182-189. Gautier-Hion A., Gautier J. (1986). Sexual dimorphism, social units and ecology among sympatric forest guenons. Symposia of the Society for the Study of Human Biology: 24, 61-77. 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. Lernould J. (1988). Classification and geographical distribution of guenons: a review. In: Gautier-Hion A., Bourlière F., Gautier J., Kingdon J. (Eds). A Primate Radiation: Evolutionary Biology of the African Guenons. Cambridge University Press, New York: pp 54-78. Loireau J., Gautier-Hion A. (1988). Olfactory marking behaviour in guenons and its implications. In: Gautier-Hion A., Bourlière F., Gautier J., Kingdon J. (Eds). A Primate Radiation: Evolutionary Biology of the African Guenons. Cambridge University Press, New York: pp 246-253. Maté C., Escobar M., Colell M. (1995). Preliminary observations on the ecology of forest cercopithecidae in the Kikofe-Ikomaloki region (Ikela, Zaire). Folia Primatol.: 64, 196-200. McGraw S. (1994). Census, habitat preference and polyspecific association of six monkeys in the Lomako Forest, Zaire. Amer. J. Primatol.: 34 (4), 295-308. 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. Muriuki J.W., Tsingalia M.H. (1990). A new population of de Brazza's monkey in Kenya. Oryx: 24 (3), 157-162. Oates J.F. (1996). African Primates Status Survey and Conservation Action plan. IUCN/SSC Primate Specialist Group. Usongo L., Fimbel C. (1995). Preliminary survey of arboreal primates in Lobeke Forest Reserve, south-east Cameroon. African Primates IUCN/SSC Primate Specialist Group: 1 (2), 46-48. 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.
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||