Elephant (Loxodonta africana) impact on trees used bynesting vultures and raptors in South Africa

Negative influences on the establishment and persistence of large trees used by tree-nesting birds as nesting sites represent a potential threat to vultures and raptors. We monitored large trees and their surrounding vegetation and analysed whether trees with nesting sites are at risk due to elephant impact. Trees with nests did not differ in elephant impact from control trees without nests, and the survival rates of trees with nests and the actual nests within the trees showed that nests decreased at a faster rate than the trees themselves. Elephant damage did not affect the persistence of nests over the 5-year monitoring period. However, the presence of insects and fungus on large trees was negatively related to tree survival, thereby indicating that elephant impact could indirectly facilitate insect and fungus attack and shorten the lifespan of a tree

Optimization of net returns from wildlife consumptive and non-consumptive uses by game reserve management

Landowners and game reserve managers are often faced with the decision whether to undertake consumptive (such as hunting) and/or non-consumptive (such as tourism) use of wildlife resources on their properties. Here a theoretical model was used to examine cases where the game reserve management allocated the amount of land devoted to hunting (trophy hunting) and tourism, based on three scenarios: (1) hunting is separated from tourism but wildlife is shared; (2) hunting and tourism co-exist; and (3) hunting and tourism are separated by a fence. The consumptive and non-consumptive uses are not mutually exclusive; careful planning is needed to ensure that multiple management objectives can be met. Further, the analysis indicates that the two uses may be undertaken in the same area. Whether they are spatially, or temporally separated depends on the magnitude of the consumptive use. When consumptive use is not dominant, the two are compatible in the same shared area, provided the wildlife population is sufficiently large

The spatial scaling of habitat selection by African elephants

1. Understanding and accurately predicting the spatial patterns of habitat use by organisms is important for ecological research, biodiversity conservation and ecosystem management. However, this understanding is complicated by the effects of spatial scale, because the scale of analysis affects the quantification of species–environment relationships. 2. We therefore assessed the influence of environmental context (i.e. the characteristics of the landscape surrounding a site), varied over a large range of scales (i.e. ambit radii around focal sites), on the analysis and prediction of habitat selection by African elephants in Kruger National Park, South Africa. 3. We focused on the spatial scaling of the elephants’ response to their main resources, forage and water, and found that the quantification of habitat selection strongly depended on the scales at which environmental context was considered. Moreover, the inclusion of environmental context at characteristic scales (i.e. those at which habitat selectivity was maximized) increased the predictive capacity of habitat suitability models. 4. The elephants responded to their environment in a scale-dependent and perhaps hierarchical manner, with forage characteristics driving habitat selection at coarse spatial scales, and surface water at fine spatial scales. 5. Furthermore, the elephants exhibited sexual habitat segregation, mainly in relation to vegetation characteristics. Male elephants preferred areas with high tree cover and low herbaceous biomass, whereas this pattern was reversed for female elephants. 6. We show that the spatial distribution of elephants can be better understood and predicted when scale-dependent species–environment relationships are explicitly considered. This demonstrates the importance of considering the influence of spatial scale on the analysis of spatial patterning in ecological phenomena