Desert-dwelling African elephants (Loxodonta africana) in Namibia dig wells to purify drinking water

作者：Ramey Eva M; Ramey Rob R^*; Brown Laura M; Kelley Scott T

来源：Pachyderm, 2013, (53): 66-72.

In the arid regions of southern Africa, elephants (Loxodonta africana) are known to dig wells using their feet and trunks to access water beneath the surface of dry sandy riverbeds. This behaviour is observed even in areas where surface water is readily available. Desert-dwelling elephants of northwestern Namibia also routinely damage borehole infrastructure to access water, even when water is available in artificial drinking pools. This study sought to determine the qualities of the water in %26apos;elephant wells%26apos; and boreholes that prompt elephants to go to such extremes to access it. This study compared faecal coliform bacterial counts in water sampled from recently dug elephant wells and boreholes with samples from the nearest surface water available to elephants in the arid Kunene region of northwestern Namibia. Results of 13 pairwise comparisons collected over two field seasons revealed significantly lower coliform counts in the elephant wells than in the nearest surface water or drinking pools. Coliform counts from the two boreholes in the study area, periodically damaged by elephants, were also dramatically lower. Alternatively, we found no evidence that elephant wells were less saline than nearby surface waters. We conclude that these behaviours are attempts by elephants to access less-contaminated drinking water. Understanding elephant behaviour in selecting water sources may also help in the development of more effective measures to protect artificial water sources and better provide for the needs of desert-dwelling elephants.

• 出版日期2013-6