Water for African Elephants (Loxodonta Africana): faecal microbial loads affect use of artificial waterholes

Abstract

Surface water availability is a fundamental constraint on herbivore distribution in semi-arid savanna regions. Artificial water provisioning has become a common practise in managing herbivore populations, especially in water scarce protected areas, where the aim is to increase populations while limiting their spatial dispersion. Artificial waterholes in semi-arid protected areas ensure that water is locally available to animals for extended periods, and make wildlife more accessible to tourists. On the other hand, they limit animal movement which contributes towards habitat deterioration. Challenges of artificial water provisioning exacerbate in the presence of African elephants (Loxodonta africana), an ecosystem engineer capable of transforming environments. We used camera traps to monitor elephant visitation at 21 artificial waterholes in various regions of the Kruger national park, and assessed water quality properties to determine the drivers of waterhole preference. The abundance of adult elephant per sampling site in relation to water quality metrics was assessed using linear mixed models (LMMs). A total of 1421 elephants were recorded drinking from the waterholes. There were no significant correlations between elephant abundance and physicochemical properties. However, there was a strong negative interaction between elephant abundance and levels of Escherichia coli in water. Our findings show that elephants avoid drinking water with high levels of faecal microbial loads. Since elephants are water dependant, we therefore concluded that their local landscape use and movement patterns at a fine scale is also primarily influenced by the quality of available water.