A decision support model to evaluate the effects of drought and stocking rate on beef cattle properties in northern australia

Abstract

In northern Australia, the severity of the effect of drought on cattle depends on the stocking rate. Management of herd size is therefore a compromise between harvesting production in average years and the risk of losses in a drought. A spreadsheet model than can be used to evaluate herd performance and cashflow, using annual rainfall as the only climate input is described. The model relies on a proxy for pasture availability derived from annual rainfall and stocking rate. This proxy is used for the estimation of reproduction, mortality and liveweight gain. Economic information is calculated to the level of cashflow. The model has been used to evaluate the question of drought and stocking rate in terms of economic risk and deterioration of native pastures, and to help determine which type, and the number, of cattle that should be sacrificed in a drought. From authors' summary.