Artiodactyla Id code: amd174Bovidae Kobus ellipsiprymnus (Ogilby, 1833) (Eng) Common waterbuck (Fre) Cobe à croissant Taxonomic notes Two subspecies recognised: K. e. ellipsiprymnus and K. e. defassa (East, 1996). IUCN threat category Lower Risk, conservation dependent (LR: cd) as Kobus ellipsiprymnus; as K. e. defassa (Defassa waterbuck) in Angola, Benin, Burkina Faso, Burundi, Cameroon, C.A.R., Chad, Congo, Ivory Coast, Ethiopia, Gabon, Gambia (ex?), Ghana, Guinea, Guinea-Bissau, Kenya, Mali, Niger, Nigeria, Rwanda, Senegal, Sierra Leone, Sudan, Tanzania, Togo, Uganda, former Zaire, Zambia, and as K. e. ellipsiprymnus (Ellipsen waterbuck) in Botswana, Ethiopia, Kenya, Malawi, Mozambique, Namibia, Somalia, South Africa, Swaziland, Tanzania, Zambia, Zimbabwe. Available information Literature on the species is available for most of its range of distribution, but the ecology of the species has been studied mainly in the eastern and southern part of the continent. East Africa: Authors have focused mainly on population density, structure, and behavioural aspects of its ecology (Eltringham, 1980; Wirtz, 1982). Both these authors include an accurate description of the habitat in which the animals were observed. A study in captivity on their water requirements was conducted by Taylor et al. (1969). Species' presence and some information on its ecology in Somalia are found in Funaioli (1971), while Yalden et al. (1996) discuss its distribution in Ethiopia and Eritrea, giving particular attention to its habitat. Conservation issues and status of the species in the Jubba Valley (Somalia) are analysed in Varty (1988); the author includes some information on its habitat use. Southern Africa: A complete review of the information available on the ecology and distribution of this species is found in Mills & Hes (1997) and Skinner & Smithers (1990), while Rowe-Rowe (1994) limits his analysis to the Natal region (South Africa). Habitat selection and requirements were investigated in several protected areas of Transvaal (South Africa) by Hirst (1975), while aspects of seasonal habitat use and water dependence are discussed in Dunham (1994); population structure and dynamics are described in Melton (1983). Distribution and density of this species has recently been monitored in Botswana (Anonymous, 1993; 1994a; 1994b). West Africa: Literature available mainly concerns the species' presence and density in specific protected areas, and only a very brief description of the habitat and ecology is generally included (Afolayan & Ajayi, 1980; Ayeni, 1980; Geerling & Bokdam, 1973; Stark, 1986). Osemeobo (1988) describes the status of several mammal species, including the waterbuck, in Nigeria, in relation to agriculture and other human activities. An extensive analysis of aspects of habitat use and requirements is found in De Bie (1991), who studied the ungulate community in the Baoulé District (Mali). General information on the species' ecology is found in Kingdon (1997) and Stuart & Stuart (1997). East (1988, 1989, 1990) discusses status and distribution in each country in which the species occurs, also giving some information its ecology, particularly its habitat requirements. Known extent of occurrence 
The waterbuck is widely, although patchily, distributed throughout Africa (East, 1996). It is considered extinct or probably so in Gambia. Its distribution map was obtained using the maps in Estes (1991) and Skinner & Smithers (1990). It was then refined on the basis of different country maps in East (1988, 1989, 1990), as indicated by Dr. R. East (23 June '97) (Fig. 8.6.72.a). Categorical-discrete (CD) distribution model The species occurs in open woodland and grassland near permanent water; also present in forest savanna mosaics (Hirst, 1975; Geerling & Bokdam, 1973; East, 1988, 1989, 1990; Spinage, 1982). Based on these environmental preferences, the following scores were assigned (Fig. 8.6.72.b) (Tab. 8.6.72.a):
Tab 8.6.72.a: Cumulative size (km2) of areas pertaining to each environmental suitability class within the Extent of Occurrence.
Tab 8.6.72.b: Area of Occupancy fragmentation indexes. Probabilistic-continuous (PC) distribution model The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 8.6.72.c. Validation
Tab 8.6.72.c: Categorical-discrete (CD) distribution model validation parameters. Comments and conservation issues The known EO of the species is very large, stretching across most of sub-Saharan Africa, but only two thirds is classified as expected AO. The CD model is supported by the Index of Accordance (58.55%) with field work. The best parts of the range appear to be in south-eastern Africa and both models identify large unsuitable areas in the north-eastern part of the EO. Extending over a large area, the EO is evidently fragmented: the LPI shows that the largest patch of suitable area accounts for about 22% of the total AO, but the AWMSI of all classes are very high indicating a marked interspersion of areas of different suitability. About 10% of the total AO is included in existing protected areas; the species is classified as Lower Risk, conservation dependent, also to mark its dependency on the network of protected areas.
Tab 8.6.72.d: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas. References Afolayan T., Aiayi S.S. (1980). The influence of seasonality on the distribution of large mammals in the Yankari Game Reserve, Nigeria. Afr. J. Ecol.: 18, 87-96. Anonymous (1993). Aerial census of animals in northern Botswana. ULG Consultants LTD Birmingham Road, Satisford Warwick CV34 4TT England. Anonymous (1994a). Aerial census of animals in Botswana: wet season 1994. Wildlife conservation in northern Botswana. Anonymous (1994b). Status and trends of selected wildlife species in Botswana. Department of Wildlife and National Park: Research Division. Ayeni J.S.O. (1980). Management problems of the Kainji National Park, Nigeria. Afr. J. Ecol.: 18, 97-111. De Bie S. (1991). Wildlife resources in the West African savanna. Wageningen Agricultural University Papers: 91(2), 1-267. Dunham K.M. (1994). The effect of drought on the larger mammal populations of Zambezi riverine woodlands. J. Zool., Lond.: 234(3), 489-526. East R. (Ed.) (1988). Antelope Global Survey and Regional Action plans, Part I: East and North East Africa. IUCN/SSC Antelope Specialist Group. East R. (Ed.) (1989). Antelopes Global Survey and Regional Action Plans. Part 2: Southern and South-central Africa. IUCN/SSC Antelope Specialist Group. East R. (Ed.) (1990). Antelopes Global Survey and Regional Action Plans. Part 3: West and Central Africa. IUCN/SSC Antelope Specialist Group. East R. (Ed.) (1996). Antelope survey update. IUCN/SSC Antelope Specialist Group: n° 2. Eltringham S.K. (1980). A quantitative assessment of range usage by large African mammals with particular reference to the effects of elephants on trees. Afr. J. Ecol.: 18, 53-71. Estes R.D. (1991). The Behaviour Guide to African Mammals. Including Hoofed Mammals, Carnivores, Primates. The University of California Press. Funaioli U. (1971). Guida breve dei mammiferi della Somalia. Istituto Agronomico per l'Oltremare. Biblioteca Agraria Tropicale. Geerling G., Bokdam J. (1973). Fauna of the Comoé National Park, Ivory Coast. Biological Conservation: 5(4), 251-257. Hirst S.M. (1975). Ungulate-habitat relationships in a South African Woodland/Savanna Ecosystem. Wildl. Monogr: 44. Kingdon J. (1997). The Kingdon field guide to African Mammals. Academic Press, London and New York: Natural World. Melton D.A. (1983). Population dynamics of waterbuck (Kobus ellipsiprymnus) in the Umfolozi Game Reserve. Afr. J. Ecol.: 21, 77-91. Mills G., Hes L. (1997). The complete book of Southern African mammals. Struik Publishers. Osemeobo G.J. (1988). Animal wildlife conservation under multiple land-use systems in Nigeria. Environ. Conserv.: 15(3), 239-249. Rowe-Rowe D.T. (1994). The ungulates of Natal. Natal Parks, Game & Fish Preservation Board, Pietermaritzburg, Natal, R.S.A. Skinner J.D., Smithers R.H.N. (1990). The mammals of the Southern African subregion. University of Pretoria, Pretoria. Spinage C.A. (1982). A territorial antelope: the Uganda waterbuck. Academic Press, London and New York. Stark M.A. (1986). The numbers, seasonal distribution patterns, densities and biomass of the large herbivores, Benoue National Park, Cameroon. Mammalia: 50, 341-350. Stuart C., Stuart T. (1997). Field guide to the larger mammals of Africa. Struik Publishers. Taylor C.R., Spinage C.A., Lyman C.P. (1969). Water relations of the waterbuck, an East African antelope. Am. J. Phys: 217, 630-634. Varty N. (1988). Mammals and problems of their conservation in the riverine forests of the Jubba Valley, southern Somalia. Tropical Zoology: 1, 179-192. Wilson D.E., Reeder D.M. (Eds) (1993). Mammal Species of the World: A Taxonomic and Geographic Reference. Second edition. Smithsonian Institution Press, Washington D.C. Wirtz P. (1982). Territory holders, satellite males and bachelor males in a high density population of waterbuck (Kobus ellipsiprymnus) and their association with conspecifics. Z. Tierpsychol.: 58, 277-300. 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.
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