A conservation model for black rhino

Abstract

Over the past thirty years the black rhinoceros (Diceros bicornis) population in Africa has declined from about 65 000 to 3 500. In contrast the South African and Namibian population has increased four-fold to 1 000 over the same period. The recently developed national conservation strategy for black rhino has as its main goal a further four-fold increase in the current population in as short a period as possible. To achieve this, the growth rate of the population as a whole will have to be maximised. This involves removing animals from areas where the population is approaching the ecological carrying capacity and establishing new viable populations in other suitable reserves. A model incorporating what is known about the population biology of black rhino, was developed to give guidance to managers on the most appropirate harvesting strategy to adopt for their populations; in particular, to determine the rate of removals and the age and sex of individuals to be removed to attain the conservation goal as soon as possible.