Abstract

Southern Africa is expected to experience increased frequency and intensity of droughts through climate change, which will adversely affect mammalian herbivores. Using bio-loggers, we tested the expectation that wildebeest (Connochaetes taurinus), a grazer with high water-dependence, would be more sensitive to drought conditions than the arid-adapted gemsbok (Oryx gazella gazella). The study, conducted in the Kalahari, encompassed two hot-dry seasons with similar ambient temperatures but differing rainfall patterns during the preceding wet season. In the drier year both ungulates selected similar cooler microclimates, but wildebeest travelled larger distances than gemsbok, presumably in search of water. Body temperatures in both species reached lower daily minimums and higher daily maximums in the drier season but daily fluctuations were wider in wildebeest than in gemsbok. Lower daily minimum body temperatures displayed by wildebeest suggest that wildebeest were under greater nutritional stress than gemsbok. Moving large distances when water is scarce may have compromised the energy balance of the water dependent wildebeest, a trade-off likely to be exacerbated with future climate change.

Details

Title
Contrasting capabilities of two ungulate species to cope with extremes of aridity
Author
Boyers Melinda 1 ; Parrini Francesca 2 ; Owen-Smith, Norman 2 ; Erasmus Barend F N 3 ; Hetem, Robyn S 4 

 University of the Witwatersrand, Centre for African Ecology, School of Animal, Plant and Environmental Sciences, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135); University of the Witwatersrand, Brain Function Research Group, School of Physiology, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135) 
 University of the Witwatersrand, Centre for African Ecology, School of Animal, Plant and Environmental Sciences, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135) 
 University of the Witwatersrand, Global Change Institute, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135); University of Pretoria, Faculty of Natural and Agricultural Sciences, Pretoria, South Africa (GRID:grid.49697.35) (ISNI:0000 0001 2107 2298) 
 University of the Witwatersrand, Brain Function Research Group, School of Physiology, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135); University of the Witwatersrand, School of Animal, Plant and Environmental Sciences, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2490849983
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.