Artiodactyla Id code: amd214Bovidae Raphicerus campestris (Thunberg, 1811) (Eng) Steinbok (Fre) Steenbok Taxonomic notes Eight forms have been described (Meester & Setzer, 1971). IUCN threat category Not listed. Available information The species has been studied mainly in Southern Africa, and little is known on the ecology of the Eastern African population. Feeding habits were investigated in the Kruger National Park (South Africa) by Du Toit (1993). Some information on its habitat is given by Kok & Nel (1996) who focused on the effects of water availability in the Namib Desert on the presence and density of several mammal species, including the steinbok. Aspects of population structure and migratory patterns in the Kalahari Gemsbock National Park (South Africa) are described in Penzhorn (1971) and Eloff (1961) respectively. The only ecological study on this species in East Africa is the one by Moe et al. (1990), who investigate the use of patchly burnt areas in the Lake Burungi Area (northern Tanzania). Data on the species' presence are available for most of South Africa (Bruton, 1978; De Graaff & Rautenbach, 1983; Lynch, 1983, 1989; Rowe-Rowe, 1994), Angola (Paias Simoes & Crawford-Cabral, 1990), Botswana (Anonymous, 1993, 1994a, 1994b), and northern Namibia (Viljoen, 1982). Some information on the species' ecology is reported by the authors mentioned above. A detailed description of the species' ecology in southern Africa is given in Mills & Hes (1997) and Skinner & Smithers (1990). General information on the species' ecology and distribution is found in Kingdon (1997) and Stuart & Stuart (1997). Status and distribution are discussed in East (1988, 1989). Known extent of occurrence 
The steinbok occurs in Africa with two distinct populations, in the south and the east respectively. It has been recorded in Angola, Botswana, Kenya, Lesotho, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Zambia and Zimbabwe (Wilson & Reeder, 1993), while it is likely to have been completely exterminated from Uganda (East, 1996). Its distribution map was first acquired from Skinner & Smithers (1990), then adjusted in accordance with the more accurate maps in East (1988, 1989), as indicated by Dr. R. East (23 June '97) (Fig. 8.6.31.a). Categorical-discrete (CD) distribution model The species prefers open grasslands with bush and shrubs, but also occurs in cultivated areas. It is absent from dense vegetation (East, 1988, 1989; Tinley, 1969; Mills & Hes, 1997; Kingdon, 1997). Based on these environmental preferences, the following scores were assigned (Fig. 8.6.31.b) (Tab. 8.6.31.a):
Tab 8.6.31.a: Cumulative size (km2) of areas pertaining to each environmental suitability class within the Extent of Occurrence.
Tab 8.6.31.b: Area of Occupancy fragmentation indexes. Probabilistic-continuous (PC) distribution model The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 8.6.31.c. Validation
Tab 8.6.31.c: Categorical-discrete (CD) distribution model validation parameters. Comments and conservation issues The known EO is largely suitable and the best areas make up at least half of it. These figures are well supported by the result of the validation process. The northern areas appear to be of lower quality than the southern: in particular the range in Tanzania appears very fragmented into areas of different suitability. The PC model shows large areas of very low suitability there. The overall fragmentation is limited and the LPI of the total AO shows substantial continuity of the suitable ranges. About 10% of the total AO is protected and the species is not listed in the IUCN threat category system.
Tab 8.6.31.d: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas. References 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. Bruton M.N. (1978). Recent mammal records from eastern Tongaland in Kwazulu, with notes on Hippopotamus in lake Sibaka. Lammergeyer: 24, 19-27. De Graaff G., Rautenbach I.L. (1983). A survey of mammals in the newly proclaimed Karoo National Park, South Africa. Ann Mus Roy Afr Cent: 237, 89-99. Du Toit J.T. (1993). The feeding ecology of a very small ruminant, the steenbok (Raphicerus campestris). Afr. J. Ecol.: 31, 35-48. 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.) (1996). Antelope survey update. IUCN/SSC Antelope Specialist Group: n° 2. Eloff F.C. (1961). Observations on the migration and habits of the antelopes of the Kalahari Gemsbok Park, part 3. Koedoe: 4, 18-30. Kingdon J. (1997). The Kingdon field guide to African Mammals. Academic Press, London and New York: Natural World. Kok O.B., Nel J.A.J. (1996). The Kuiseb river as a linear oasis in the Namib desert. Afr. J. Ecol.: 34(1), 39-47. Lynch C.D. (1983). The mammals of the Orange Free State. Mem. van die Nasionale Mus., Bloemfontein: 18, 1-218. Lynch C.D. (1989). The mammals of the north-east Cape Province. Mem. van die Nasionale Mus., Bloemfontein: 25, 1-116. Meester J., Setzer H.W. (Eds) (1971). The Mammals of Africa, an Identification Manual. Smithsonian Institution Press, Washington D.C. Mills G., Hes L. (1997). The complete book of Southern African mammals. Struik Publishers. Moe S.R., Wegge P., Kapela E.B. (1990). The influence of man-made fires on large wild herbivores in Lake Burungi Area in Northern Tanzania. Afr. J. Ecol.: 28, 35-43. Paias Simoes A., Crawford-Cabral J. (1990). Notice on large-hoofed steenbok, Raphicerus campestris (Mammalia: Artiodactyla), from Angola. Garcia de Orta, Série de Zoologica: Lisboa, 15(2), 1-8. Penzhorn B.L. (1971). A note on the sex ratio of steinbok Raphicerus campestris in the Kalahari Gemsbok National Park. Koedoe: 14, 61-64. 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. Stuart C., Stuart T. (1997). Field guide to the larger mammals of Africa. Struik Publishers. Tinley K.L. (1969). Dik-dik Madoqua kirki in South West Africa: Notes on distribution, ecology and behaviour. Madoqua: 1, 7-33. Viljoen P.J. (1982). The distribution and population status of the larger mammals in Kaokoland, South West Africa/Namibia. Cimbebasia: A 7, 7-33. 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.
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