Effect of elephant and tourist presence on herbivore behaviour at artificial water sources in Kruger National Park, South Africa

At the landscape level, mammal home ranges are influenced by proximity to a water source. Therefore, management of surface water availability is crucial in protected areas. This management has been largely dominated by adding artificial water sources, including boreholes and earth dams. By adding these artificial water sources, African elephants (Loxodonta africana), preferring easily accessible water, can utilize this water year-round versus migrating to follow natural water movement patterns. Closing artificial water sources forces elephants to migrate to one of the remaining water sources, increasing total abundance per water hole. Unlike natural water sources, known locations and proximity to roads also increases tourist abundance at man-made boreholes and dams. Response of other water hole-dependent mammals to these changes has never been studied. The effect of the increased presence of elephants and tourists on large herbivorous mammals at artificial water sources was investigated in Kruger National Park between 30 September and 1 October 2009. This investigation was used to predict potential effects of closing these water sources on other species, focusing on the effect that elephant abundance has on other species reliant on that water source. Herbivore species, abundance, and behavior were observed for 24 hours over a two-day period at four study sites (two dams, two boreholes): De Laporte, N’watindlopfu, Nwaswitshaka, and Transport Dam. Polynomial regression analysis was performed on the five most abundant species to assess normality of arrival and leaving events. Residual plots were used to attempt to explain abnormal points through presence of elephants and/or tourists. Our results suggest that higher species abundance was correlated with presence of tourists; however, this was determined to be a negative correlation as tourists are attracted by species presence. Neither elephants nor tourists were determined to have a real behavioral effect on other species. However, due to several notable observed behaviors in other species and lack of time to complete a conclusive study, we postulate that elephants do in fact deter water source use of large herbivorous mammals that depend on dams and boreholes and that closure of certain water sources would negatively affect non-elephant herbivore usage at the remaining sites.