Elephant movement patterns in relation to human inhabitants in and around the Great Limpopo Transfrontier Park

The presence of humans and African elephants (Loxodonta africana) in the Great Limpopo Transfrontier Park can create situations of potential human–elephant conflict. Such conflict will likely be exacerbated as elephant and human populations increase, unless mitigation measures are put in place. In this study we analysed the movement patterns of 13 collared adult African elephants from the northern Kruger National Park over a period of eight years (2006–2014). We compared the occurrence and displacement rates of elephant bulls and cows around villages in the Limpopo National Park and northern border of the Kruger National Park across seasons and at different times of the day. Elephants occurred close to villages more often in the dry season than in the wet season, with bulls occurring more frequently around villages than cows. Both the bulls and the cows preferred to use areas close to villages from early evening to midnight, with the bulls moving closer to villages than the cows. These results suggest that elephants, especially the bulls, are moving through the studied villages in Mozambique and Zimbabwe at night and that these movements are most common during the drier months when resources are known to be scarce.Conservation implications: Elephants from the Kruger National Park are moving in close proximity to villages within the Great Limpopo Transfrontier Park. Resettlement of villages within and around the park should therefore be planned away from elephant seasonal routes to minimise conflict between humans and elephants.

How free-ranging ungulates with differing water dependencies cope with seasonal variation in temperature and aridity

Large mammals respond to seasonal changes in temperature and precipitation by behavioural and physiological flexibility. These responses are likely to differ between species with differing water dependencies. We used biologgers to contrast the seasonal differences in activity patterns, microclimate selection, distance to potential water source and body temperature of the water-independent gemsbok (Oryx gazella gazella) and water-dependent blue wildebeest (Connochaetes taurinus), free-living in the arid Kalahari region of Botswana. Gemsbok were more active nocturnally during the hot seasons than in the cold-dry season, while wildebeest showed no seasonal difference in their nocturnal activity level. Both species similarly selected shaded microclimates during the heat of the day, particularly during the hot seasons. Wildebeest were further than 10 km from surface water 30% or more of the time, while gemsbok were frequently recorded >20 km from potential water sources. In general, both species showed similar body temperature variation with high maximum 24-h body temperature when conditions were hot and low minimum 24-h body temperatures when conditions were dry, resulting in the largest amplitude of 24-h body temperature rhythm during the hot-dry period. Wildebeest thus coped almost as well as gemsbok with the fairly typical seasonal conditions that occurred during our study period. They do need to access surface water and may travel long distances to do so when local water sources become depleted during drought conditions. Thus, perennial water sources should be provided judiciously and only where essential.

Home range establishment and utilization by reintroduced lions (Panthera leo) in a small South African wildlife reserve

Understanding of animal spatial behavior is essential for informed management decisions. In southern Africa, reintroduction of lions (Panthera leo) to small reserves (<1000 km² ) has increased since the early 2000s, however studies on their ranging behavior in these enclosed systems remain lacking. We applied Time Local Convex Hull (T-LoCoH) methods to study the home range establishment and utilization of 11 lions reintroduced to Dinokeng Game Reserve, South Africa, during 2011 through 2014. Lions established home ranges close to their release sites and during the following 3 years their home range sizes continued to increase, but in each individual case the size remained smaller than half of the reserve area (<70 km² ). Space use strategies differed between the core and the entire home range, with higher frequency of visits found in core areas. Exceptionally high rates (>60 separate visits) around the largest dam and along rivers suggest the importance of water and its surrounding vegetation in the lions' space utilization pattern. The home range size did not differ with season or sex of the individuals, whereas shifts in locations of home ranges revealed differences in the response of the 2 sexes to territorial conflicts and management interventions. Our study shows a dynamic home range utilization pattern and highlights the importance of both fine-scale space use patterns (frequency and duration of visits) and broad-scale home range changes in understanding the ranging behavior of reintroduced animals.

Trait-based sensitivity of large mammals to a catastrophic tropical cyclone

Extreme weather events perturb ecosystems and increasingly threaten biodiversity1. Ecologists emphasize the need to forecast and mitigate the impacts of these events, which requires knowledge of how risk is distributed among species and environments. However, the scale and unpredictability of extreme events complicate risk assessment1-4-especially for large animals (megafauna), which are ecologically important and disproportionately threatened but are wide-ranging and difficult to monitor5. Traits such as body size, dispersal ability and habitat affiliation are hypothesized to determine the vulnerability of animals to natural hazards1,6,7. Yet it has rarely been possible to test these hypotheses or, more generally, to link the short-term and long-term ecological effects of weather-related disturbance8,9. Here we show how large herbivores and carnivores in Mozambique responded to Intense Tropical Cyclone Idai, the deadliest storm on record in Africa, across scales ranging from individual decisions in the hours after landfall to changes in community composition nearly 2 years later. Animals responded behaviourally to rising floodwaters by moving upslope and shifting their diets. Body size and habitat association independently predicted population-level impacts: five of the smallest and most lowland-affiliated herbivore species declined by an average of 28% in the 20 months after landfall, while four of the largest and most upland-affiliated species increased by an average of 26%. We attribute the sensitivity of small-bodied species to their limited mobility and physiological constraints, which restricted their ability to avoid the flood and endure subsequent reductions in the quantity and quality of food. Our results identify general traits that govern animal responses to severe weather, which may help to inform wildlife conservation in a volatile climate.

Contrasting capabilities of two ungulate species to cope with extremes of aridity

Southern Africa is expected to experience increased frequency and intensity of droughts through climate change, which will adversely affect mammalian herbivores. Using bio-loggers, we tested the expectation that wildebeest (Connochaetes taurinus), a grazer with high water-dependence, would be more sensitive to drought conditions than the arid-adapted gemsbok (Oryx gazella gazella). The study, conducted in the Kalahari, encompassed two hot-dry seasons with similar ambient temperatures but differing rainfall patterns during the preceding wet season. In the drier year both ungulates selected similar cooler microclimates, but wildebeest travelled larger distances than gemsbok, presumably in search of water. Body temperatures in both species reached lower daily minimums and higher daily maximums in the drier season but daily fluctuations were wider in wildebeest than in gemsbok. Lower daily minimum body temperatures displayed by wildebeest suggest that wildebeest were under greater nutritional stress than gemsbok. Moving large distances when water is scarce may have compromised the energy balance of the water dependent wildebeest, a trade-off likely to be exacerbated with future climate change.

Integrating physiology into movement ecology of large terrestrial mammals

Movement paths are influenced by external factors and depend on an individual's navigation capacity (Where to move?), motion capacity (How to move?) and are ultimately driven by internal physiological state (Why move?). Despite physiology underlying most aspects of this movement ecology framework, the physiology-movement nexus remains understudied in large terrestrial mammals. Within this Commentary, we highlight the physiological processes that underpin the movement ecology framework and how integrating physiological measurements can provide mechanistic insights that may enhance our understanding of the drivers of animal movement. We focus on large terrestrial mammals, which are well represented within the movement ecology literature but are under-represented in movement studies that integrate physiological state. Recent advances in biologging technology allow for physiological variables, such as heart rate and body movements, to be recorded remotely and continuously in free-living animals. Biologging of body temperature may provide additional insights into the physiological states driving movement. Body temperature not only provides a measure of thermal stress, but also an index of animal wellbeing through quantification of nutrition, hydration, reproductive and disease states that may drive animal movements. Integrating measures of body temperature with fine-scale GPS locations may provide insights into causality and improve our mechanistic understanding of animal movement, which is crucial for understanding population performance and monitoring reintroduction success. We recommend that baseline studies are undertaken, linking animal movement to the underlying physiological mechanisms, to allow for the development of realistic predictive models to improve conservation efforts in the Anthropocene.

The bii4africa dataset of faunal and floral population intactness estimates across Africa's major land uses

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.