Modelling of the response of sable antelope (Hippotragus niger niger) to trophy hunting: A GIS and remote sensing approach

Abstract

The main objective of this study was to test the impact of hunting on sable (Hippotragus niger niger) habitat selection using a combination of satellite remotely sensed data and GIS based spatial analysis. Firstly, we used remotely sensed vegetation cover estimated by the normalised difference vegetation index (NDVI) to test whether hunted sables selected more closed woodland habitats, i.e., an uncharacteristic habitat for sable, while those not exposed to hunting selected more open woodland habitats, i.e., characteristic habitat for sable. Secondly, we tested whether terrain based visibility modelled from remotely sensed data explains sable Flight Initiation Distance (FID), an indicator of fearfulness in hunted animal species, better than vegetation based visibility measured in the field. We tested these hypotheses in a study area consisting of one hunting area and one non-hunting area of northwestern Zimbabwe. Our results show that hunted sables significantly (P < 0.05) selected more closed woodland than those not exposed to hunting. Our results also show that remotely sensed Advanced Spaceborne Thermal Emission and Reflection Radiometer Digital Elevation Model (ASTER DEM) derived visibility could explain FID of sable better than field measured vegetation based visibility. Results of this thesis open new ground in spatial ecological understanding of wildlife species such as the threatened sable antelope