ARTIODACTYLA

Artiodactyla Id code: amd172

Bovidae
Hippotragus equinus

(Desmarest, 1804)

(Eng) Roan antelope

(Fre) Hippotrague, antilope chevaline

Taxonomic notes

No significant taxonomic notes.

IUCN threat category

Lower Risk, conservation dependent (LR: cd).

Available information

The species' ecology has been studied mainly in southern Africa, and information available for east, central and west Africa mainly concerns its status and presence in protected areas.

Southern Africa: The main aspects of the ecology of the species are described by Wilson & Hirst (1979) who studied the species in Transvaal (South Africa). Joubert (1974) also did research on the species in the Transvaal (South Africa), focusing on the behavioural aspects of its ecology. Ecology, status and distribution of this antelope in Natal (South Africa) are described by Rowe-Rowe (1994). Updated data on the specie' presence and population numbers in South Africa are available through the National Parks Board. Status and distribution in Botswana have recently been monitored (Anonymous, 1993, 1994a, 1994b); data on the species' presence and population density in the Sioma-Ngwezi Park (Zambia) are given by Tembo (1995). A complete and detailed account on the species' ecology and distribution in the southern African subregion is given by Mills & Hes (1997) and Skinner & Smithers (1990).

East Africa: No specific studies on this species have been conducted. Some information on its presence in Eritrea and Ethiopia are found in Yalden et al. (1996), who also give some information on its habitat.

Central and West Africa: Status, population density, and some ecological notes are available for several protected areas of Ivory Coast (Geerling & Bodkam, 1973), Cameroon (Stark, 1986; Tchamba & Elkan, 1995), Niger (Poché, 1974), and Nigeria (Ayeni, 1980; Ajayi et al., 1981; Osembobo, 1988). De Bie (1991) conducted a very detailed study on the ecology of the ungulate community in the Baoulé region (Mali), focusing particularly on its environmental adaptation and needs. Notes on its presence in former Zaire are found in Verschuren (1975).

General information on the species' ecology is given by Estes (1991), Kingdon (1997) and Stuart & Stuart (1997). East (1988, 1989, 1990) analyses status and distribution in each country in which the species occurs and gives also some information on its ecology.

Known extent of occurrence

The roan antelope occurs from Senegal to west Ethiopia, southwards to northern South Africa, north Botswana and Namibia (Wilson & Reeder, 1993; East, 1996). Its distribution map was obtained from Skinner & Smithers (1990), then updated using different country maps in East (1988, 1989, 1990) as indicated by Dr. R. East (23 June '97) (Fig. 8.6.67.a).

Categorical-discrete (CD) distribution model

This species is found in all types of open woodland or shrub savanna; water must be nearby (De Bie, 1991; East, 1988, 1989, 1990).

Based on these environmental preferences, the following scores were assigned (Fig. 8.6.67.b) (Tab. 8.6.67.a):

Score
1^(*)	Woodlands, woodland mosaics and transition, shrublands and shrubland mosaics.
2	Grasslands, dry bushlands, semi-desert vegetation and forest/savanna mosaics.
3	Forests and croplands.
^{(*) Scores decreased for vegetation types occurring outside a 10-km buffer around permanent water.}

	suitable		moderately suitable		unsuitable		Total
OCCURRENCE	km²	%	km²	%	km²	%	km²	%
certain	3 311 142	42	3 506 574	45	953 269	12	7 770 985	99
possible	7 024	0	32 889	0	9 064	0	48 977	1
Total	3 318 166	42	3 539 463	45	962 333	12	7 819 962	100

Tab 8.6.67.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	2 789	1 200	27 927	17.03	1.33	24.3
moderately suitable	3 861	920	17 917	12.01	1.33	17.83
Total AO	465	14 837	209 949	54.14	1.32	23.28

Tab 8.6.67.b: Area of Occupancy fragmentation indexes.

Probabilistic-continuous (PC) distribution model

The output of the probabilistic-continuous (PC) distribution model is shown in Fig. 8.6.67.c.

Validation

% of EO in sample areas	Number of valid plots	Index of Accordance (%)
4.34	86	47.67

Tab 8.6.67.c: Categorical-discrete (CD) distribution model validation parameters.

Comments and conservation issues

Uganda is currently excluded from the known EO, where the models also indicate the unsuitability for the species. Nevertheless the Index of Accordance (47.67%) suggests some caution in interpreting the CD model's results. Most of the EO is classified as either suitable or moderately suitable, but it is highly fragmented: both classes of areas have a very low LPI. Taking two classes together improves the LPI but it is still at relatively low levels (54.14%) compared to most of the other species. The AWMSI confirms that the total AO is the product of a very intricate mosaic of areas of different suitability classes. Like most large mammals, this species is often restricted to existing protected areas, which account for only 10% of the total AO.

OCCURRENCE	SUITABILITY CLASS	inside	outside	Total
certain	suitable	5.40	36.94	42.34
	moderately suitable	3.50	41.34	44.84
	unsuitable	1.19	11	12.19
possible	suitable	0	0.09	0.09
	moderately suitable	0	0.42	0.42
	unsuitable	0	0.12	0.12
Total		10.10	89.90	100

Tab 8.6.67.d: Percent of environmental suitability classes within EO (as obtained from the categorical-discrete distribution model) inside and outside the protected areas.

References

Ajayi S.S., Afolayan T., Milligan K. (1981). A survey of wildlife in Kwiambana Game Reserve, Nigeria. Afr. J. Ecol.: 19, 295-298.

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.

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.

Estes R.D. (1991). The Behaviour Guide to African Mammals. Including Hoofed Mammals, Carnivores, Primates. The University of California Press.

Geerling G., Bokdam J. (1973). Fauna of the Comoé National Park, Ivory Coast. Biological Conservation: 5(4), 251-257.

Joubert S.C.J. (1974). The social organisation of the roan antelope Hippotragus equinus, and its influence on the spatial distribution of the herds in the Kruger National Park. In: Geist V., Walther F.R. (Eds). The Behavior of Ungulates and Its Relation to Management. The papers of an International symposium held at the University of Calgary, Alberta, Canada: 2-5 November 1971. IUCN Publ. New Series, Morges Switzerland: pp 661-675.

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

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.

Poché R.M. (1974). Notes on roan antelope (Hippotragus equinus Desmarest) in West Africa. J. Appl. Ecol.: 11, 963-968.

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.

Stark M.A. (1986). The numbers, seasonal distribution patterns, densities and biomass of the large herbivores, Benoué National Park, Cameroon. Mammalia: 50, 341-350.

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

Tchamba M., Elkan P. (1995). Status and trends of some large mammals and ostriches in Waza National Park, Cameroon. Afr. J. Ecol.: 33(4), 366-376.

Tembo A. (1995). A survey of large mammals in Sioma-Ngwezi Park, Zambia. Afr. J. Ecol.: 33, 173-174.

Verschuren J. (1975). Wildlife in Zaire. Oryx: 13(2), 149-163.

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.

Wilson E.E., Hirst S.M. (1979). Ecology and factors limiting roan and sable populations. Wildl. Monogr: 63, 1-111.

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.