The Response of a Black Rhinoceros (Diceros Bicornis Minor) Population to Harvesting for Translocation

Abstract

Species recovery in a fragmented landscape relies on translocation. Harvesting and translocation of the black rhinoceros (Diceros bicornis minor) from Hluhluwe-iMfolozi Park, South Africa, is an integral part of the management program of the critically endangered black rhino. Translocation aims to found new sub-populations and reduce population densities within source populations. However, little research has focused on the demographic effects harvesting has on source populations and how individuals occupy space. In this study I assessed; 1) the sub-adult population's demographic response to harvest intensity, 2) the temporal ratio of dependents per adult females in response to harvesting, 3) the population density of male and female rhino within the harvested rhino's range in response to the harvested rhino's sex, and 4) individual male and female rhino's spatial response in relation to the sex harvested. My results showed that the proportion of sub-adults did not increase in relation to harvesting intensity and the proportion of dependents per adult female did not change after harvesting. Additionally, the un-harvested population density did not change post harvesting. Furthermore, my results indicate that individual rhino's spatial location and organisation may be influenced by the sex of neighbouring rhino and this may slow re-colonisation of harvested ranges. These results highlight the need to be able to assess the true effect harvests have on juvenile mortality within source populations and the need to understand what other factors apart from resources determine the spatial organisation of rhino populations. Improving the productivity of source populations relies on individuals in the population utilising harvested areas. Understanding how individuals utilise harvested areas before and after harvesting will lead to a greater understanding of sustainable harvesting for translocation, and therefore greatly increase the scientific understanding of restoration ecology.