Rules of habitat use by elephants Loxodonta africana in southern Africa: insights for regional management

Abstract

Managers in southern Africa are concerned that continually increasing elephant populations will degrade ecosystems. Culling, translocation and birth control are flawed solutions. An alternative is providing elephants more space but this hinges on identifying landscape preferences. We examined two diverse eco- systems and uncovered similarities in elephant habitat use, expressing these as 'rules'. We considered arid Etosha National Park, (Namibia) and the tropical wood- lands of Tembe Elephant Park (South Africa) and Maputo Elephant Reserve (Mozambique). Landscape data con- sisted of vegetation types, distances from water and settlements. To surmount issues of scale and availability we incorporated elephant movements as a function that declined as distance from an elephant's location in- creased. This presumes that elephants optimize trade- offs between benefiting from high-quality resources and costs to find them. Under a likelihood-based approach we determined the important variables and shapes of their relationships to evaluate and compare models separated by gender, season and location. After consid- ering elephants' preferences for areas nearby, habitat use usually increased with proximity to water in all loca- tions. Elephants sought places with high proportions of vegetation, especially when neighbouring areas had low vegetative cover. Lastly, elephants avoided human set- tlements (when present), and cows more so than bulls. In caricature, elephants preferred to move little, drink easily, eat well, and avoid people. If one makes more areas available, elephants will probably favour areas near water with high vegetative cover (of many different types) and away from people. Managers can oblige elephants' preferences by supplying them. If so, they should anticipate higher impacts to neighbouring vegetation.