Effect of artificial water points on the movement and behaviour of desert-dwelling elephants of north-western Namibia

Abstract

In November 2002, two artificial water points (AWPs) were drilled in the Hoanib River, north-western Namibia. This arid area (< 100 mm annual rainfall) seasonally supports a relatively large desert-dwelling elephant popu- lation. The range and the distribution of these elephants are determined by the distance that they need to forage from water. Before drilling the AWPs, female family units, hindered by their young, were limited in their move- ment, needing to stay close to natural permanent water sources. Free-ranging adult male elephants had larger ranges as they were less constrained in their drinking frequencies. However, the drilling of AWPs allowed family units to shift their ranges spatially beyond their normal foraging areas. Free-ranging males did not spatially shift their feeding areas but foraged closer to the AWPs. The seasonal movement of one family unit was disrupted by these AWPs, its members becoming more or less permanent residents along the river. AWPs have also changed the frequency and manner of drinking behaviour in this elephant population.