1. Conservation Services Division, Scientific Services, South African National Parks (SANParks), Kimberley 8301, South Africa
2. Department of Geography, Faculty of Natural and Agricultural Sciences, University of Free State, Bloemfontein 9301, South Africa
3. Centre for Environmental Studies, Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Hatfield, Pretoria 0181, South Africa
4. Applied Behavioural Ecology and Ecosystem Research Unit, Department of Environmental Sciences, University of South Africa, Private Bag X6, Florida Campus, Roodepoort 1710, South Africa
5. Department of Statistics and Actuarial Science, Stellenbosch University, Private Bag X1 Matieland, Stellenbosch 7602, South Africa