1. Concerns over the ecological impacts of high African elephant Loxodonta africana densities suggest that it may be necessary to control their numbers locally, although the best management approach is still widely debated. Artificial water supply is believed to be a major cause of local overabundance, and could be used as a potential tool to regulate elephant distribution and impact across landscapes, but its effect on elephants at the population scale has never been studied. 2. We assessed how dry-season surface-water availability constrained the distribution of an entire elephant population, using aerial and waterhole census data from Hwange National Park, Zimbabwe. The study was initiated in 1986, when the population was released from culling. We studied how artificial waterholes, holding water throughout the dry season, and vegetation production, estimated from a normalized difference vegetation index (NDVI), influenced the long-term distribution of elephant densities. We also investigated how the elephant distribution responded to changes in population density and annual rainfall, a driver of surface-water availability. 3. Long-term dry-season elephant densities across the park tended to increase with vegetation production, and increased asymptotically with the density of artificial waterholes. 4. Since the culling stopped, dry-season elephant densities have increased in most areas of the park, except in areas of low vegetation production and low water availability. Interannual fluctuations in elephant distribution are linked to rainfall variability through its effect on surface-water availability. During dry years elephants concentrated in areas where artificial pumping maintained surface-water availability during the dry season. 5. During dry years elephant numbers at waterholes increased because of reduced surface-water availability, and elephants were distributed more evenly across waterholes, although active waterholes were unevenly distributed across the park. 6. Synthesis and applications . Surface-water availability drives the distribution and abundance of elephants within Hwange National Park, and therefore appears to be at the heart of the trade-off between elephant conservation and the extent of their impact on ecosystems. Artificial manipulation of surface water is one of the tools available for the management of elephant populations and should not be overlooked when considering options for controlling elephant numbers in places where they are considered to be overabundant.

https://besjournals.onlinelibrary.wiley.com/doi/epdf/10.1111/j.1365-2664.2007.01300.x

Managing heterogeneity in elephant distribution: interactions between elephant population density and surface‐water availability

Fences and artificial water affect African savannah elephant movement patterns

https://repository.up.ac.za/bitstream/handle/2263/2622/VanAarde_Megaparks(2007).pdf?sequence=1

Megaparks for metapopulations: Addressing the causes of locally high elephant numbers in southern Africa

How to respond to growing elephant numbers in the Kruger National Park and elsewhere in southern Africa continues to be a contentious issue. In contrast to the public perception, scientists have attained a high degree of consensus on the ecological basis for such decisions. In this article we summarize these ecological principles and the management responses that are indicated, in order to counter some of the misunderstanding that has been evident in the popular media.

A scientific perspective on the management of elephants in the Kruger National Park and elsewhere : elephant conservation

Human-elephant conflict is a major conservation concern in elephant range countries. A variety of management strategies have been developed and are practiced at different scales for preventing and mitigating human-elephant conflict. However, human-elephant conflict remains pervasive as the majority of existing prevention strategies are driven by site-specific factors that only offer short-term solutions, while mitigation strategies frequently transfer conflict risk from one place to another. Here, we review current human-elephant conflict management strategies and describe an interdisciplinary conceptual approach to manage species coexistence over the long-term. Our proposed model identifies shared resource use between humans and elephants at different spatial and temporal scales for development of long-term solutions. The model also highlights the importance of including anthropological and geographical knowledge to find sustainable solutions to managing human-elephant conflict.

Human-Elephant Conflict: A Review of Current Management Strategies and Future Directions

http://www7.nau.edu/mpcer/direnet/publications/publications_d/files/deBeer-2006.pdf

Y. de Beer

Papers

Elephants and low rainfall alter woody vegetation in Etosha National Park, Namibia

Do landscape heterogeneity and water distribution explain aspects of elephant home range in southern Africa's arid savannas?

Elephant population biology and ecology