Responses of African livestock and wild herbivores to drought

The ways in which herbivores regulate their energy and water balance under hot, dry conditions are briefly reviewed. Cattle account for about two-thirds of the biomass of domestic stock in Africa, but their Eurasian origin means that their physiology and grazing behaviour are not wholly adapted to the natural pastures and climate of Africa, especially when drought strikes. In general, most herbivores can withstand heat and water shortage quite well, provided conditions do not become extreme. However, malnutrition will inevitably develop as pasture productivity declines under drought and overgrazing. This will affect most seriously animals that cannot range far from water and that depend mainly on drought susceptible grasses rather than on more resistant shrubs and trees.