Fencing conservation areas is ubiquitous in South Africa, however, the impact of these on predator ecology has not been tested. We used relationships between prey abundance and predator space use to create equations to predict the home range size of lions Panthera leo and leopards Panthera pardus. We then successfully tested these predictions using published data (Phinda, Makalali) and home range estimates from radio collared individuals reintroduced to Addo Elephant National Park. Spotted hyaena Crocuta crocuta ranges also seem food dependent. Lion home ranges in Addo (114 ± 5 km 2 ) required 180 fixes to be accurately estimated, spotted hyaena ranges (91 ± 10 km 2 ) required 200 fixes, and the solitary leopard had 295 fixes for a range of 38 km 2 . There were no sexual differences in home range sizes of lions or hyaenas. The daily food intake rate of lions, measured during continuous follows, was 9.8 kg per female equivalent unit. Dominant male lions (14.3 km for 8.3 kg) traveled furthest but obtained the least amount of food per day compared to subordinate males (8.9 km for 16.0 kg) and females (5.8 km for 17.9 kg). Subordinate males traveled the fastest and during the day, to avoid competition and harassment from the dominant males. From an evolutionary viewpoint, the use of fences for conservation has not affected the natural behaviour of the predators as they still conform to predictions derived from unfenced reserves; that is, prey abundance is the key factor in determining space use of large predators.

Africa's large predator guild competes for a limited food resource base. To minimize the degree of competition, we hypothesized that the two largest members of this guild and its fiercest competitors, the lion and the spotted hyaena, would partition their activity patterns to avoid interacting. We used 96‐h continuous follows of focal animal(s) to determine when the six radio‐collared lions and eight radio‐collared spotted hyaenas, reintroduced into Addo Elephant National Park in 2003/2004, were active using a binomial measure of activity which was defined as movements >100 m during each hourly period. Contrary to our predictions, lions and hyaenas did not partition their activity times, probably because of their current low population densities. Both species exhibited a crepuscular activity pattern although hyaenas were far less active during daylight. A sub‐adult lioness minimized competitive interactions by becoming diurnal. This is likely to be a common strategy for lions that have been expelled from their natal pride to become nomadic, as it allows them to minimize kleptoparasitic and agonistic interactions from competitively dominant conspecifics and competitors. The increase in testosterone that occurs in males upon reaching sexual maturity, darkens their pelage and causes them to be more directly impacted by the heat, and thereby affords females an opportunity to escape from males during hot temperatures. Similarly, the longer pelage of young hyaenas restricts their activity to the cooler night‐time.

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Research on coursing predators has revealed that actions throughout the predatory behavioral sequence (using encounter rate, hunting rate, and kill rate as proxy measures of decisions) drive observed prey preferences. We tested whether similar actions drive the observed prey preferences of a stalking predator, the African lion Panthera leo. We conducted two 96 hour, continuous follows of lions in Addo Elephant National Park seasonally from December 2003 until November 2005 (16 follows), and compared prey encounter rate with prey abundance, hunt rate with prey encounter rate, and kill rate with prey hunt rate for the major prey species in Addo using Jacobs' electivity index. We found that lions encountered preferred prey species far more frequently than expected based on their abundance, and they hunted these species more frequently than expected based on this higher encounter rate. Lions responded variably to non-preferred and avoided prey species throughout the predatory sequence, although they hunted avoided prey far less frequently than expected based on the number of encounters of them. We conclude that actions of lions throughout the predatory behavioural sequence, but particularly early on, drive the prey preferences that have been documented for this species. Once a hunt is initiated, evolutionary adaptations to the predator-prey interactions drive hunting success.

Optimality theory suggests that territorial scent marks are under selective pressure through the information they provide about competitive quality/reproductive status and so should be situated to maximize their detection to alert conspecifics that they are intruding upon the territory of a resident. Factors that increase mark detectability are consequently beneficial to both resident and intruder by allowing tactical withdrawal by intruders and, thus, reducing the costs of conflict. We tested whether black-backed jackals (Canis mesomelas) preferentially deposited territory marks on substrates (rocks or faeces) in two separate sites in South Africa's Addo Elephant National Park. Elephant (Loxodonta africana) dung piles were preferentially defecated upon by jackals in both sites. Where black rhinoceros (Diceros bicornis) was present at relatively high density, rhino middens were also preferentially marked by jackals; however, jackals resorted to defecating on elevated surfaces, such as rocks, where rhinos were scarce. We hypothesize that the odour of elephant and rhino dung may increase the detectability of jackal markings while providing an additional olfactory signal component, while rocks and elephant dung provide visual amplification. Manipulative experimentation will be necessary to confirm our multimodal amplification hypothesis.

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Predators can induce behavioral changes in prey that influence vigilance, grouping patterns, and space use, and these can ultimately affect prey demography and trophic interactions. Consequently, prey must respond to the risk of predation, but little is known about the features that drive the spatial responses of prey species to predators. We tested what factors affected the proximity of prey to the lions reintroduced to Addo Elephant National Park, South Africa. We also tested whether prey species that are preferentially killed by lions revealed greater responsiveness than those that are not, and whether prey respond to predator behavioral states and hunger. From 1588 observations of potential prey locations in relation to lions under varying wind directions, lion behaviors, and hunger states throughout the day and night, we found no evidence of wind‐driven odor responses affecting prey proximity to lions. Prey species that were not preferentially preyed upon by lions occurred closer to lions than those species that lions prefer to hunt. Prey were closer to lions performing noisy behaviors compared to those performing quiet behaviors. Prey were more likely to be closer to covertly behaving lions and further from stationary lions. Our results, compared to the published literature and accepted dogma of the primacy of odor in predator detection, suggest large vertebrate prey responses to predators in intact, multi‐species assemblages are context dependent.