Resource partitioning promotes coexistence among guild members, and carnivores reduce interference competition through behavioural mechanisms that promote spatio-temporal separation.  We analyzed sympatric lion and spotted hyena movements and activity patterns to ascertain the mechanisms facilitating their coexistence within semi-arid and wetland ecosystems.  We identified recurrent high-use (revisitation) and extended stay (duration) areas within home ranges, and correlated environmental variables with movement-derived measures of inter- and intraspecific interactions.  Spatial overlaps among lions and hyenas occurred at edges of home ranges, around water-points, along pathways between patches of high-use areas, and expanded during the wet season.  Lions shared more of their home ranges with spotted hyenas in arid ecosystems, but shared more of their ranges with conspecifics in mesic environments.  Despite shared space use, we found evidence for subtle temporal differences in the nocturnal movement and activity patterns between the two predators, suggesting a fine localized-scale avoidance strategy.  Revisitation frequency and duration within home ranges were influenced by interspecific interactions, subsequent to land cover categories and diel cycles.  Intraspecific interactions were also important for lions and, for hyenas, moon illumination and ungulates attracted to former anthrax carcass sites in Etosha, with distance to water in Chobe/Linyanti.  Recursion and duration according to locales of competitor probabilities were similar among female lions and both sexes of hyenas, but different for male lions.  Our results suggest that lions and spotted hyenas mediate the potential for interference competition through subtle differences in temporal activity, fine-scale habitat use differentiation, and localized reactive-avoidance behaviours.  These findings enhance our understanding of the potential effects of interspecific interactions among large carnivore space-use patterns within an apex predator system, and show adaptability across heterogeneous and homogeneous environments.  Future conservation plans should emphasize the importance of inter- and intraspecific competition within large carnivore communities, particularly moderating such effects within increasingly fragmented landscapes.

Background Interference competition among sympatric carnivores can potentially influence species viability through population reduction or extinction, and has important implications for the structure and function of large carnivore communities. Carnivores may mitigate the risk of competition through fine-scaled spatial or temporal separation that subsequently affects predator interactions and community dynamics. Simultaneous telemetry records of sympatric carnivores allows for an in-depth analysis of individual space-use patterns and association metrics. Together with the application of a novel method for analyzing fine-scaled movement interactions, quantifying spatiotemporal separation between predator species provides insight into understanding the dynamic interactions among co-existing carnivores. Methods We analyzed GPS satellite relocation data from 17 lions (Panthera leo) and 14 spotted hyenas (Crocuta crocuta) over four-years, across two distinct ecosystems. Data were used to investigate lion and hyena space-use patterns and fine-scale movement of intra- and interspecific dyads. We assessed home range overlap among lion and spotted hyena, and applied a novel T-LoCoH (Time-Local Convex Hull) method to study species range overlaps from an interaction perspective. We also present the first application of our dyadic movement methodology to characterize the relative movement of lion and spotted hyena dyads. Results Heterospecific home-range overlap between lion prides and hyena clans was considerably greater than conspecific pride-pride and clan-clan overlap. Spatial overlaps among heterospecific competitors occurred mainly at the edge of home ranges, and were indicative of joint, contemporaneous space-use. Close encounters between individual lion and hyena provided opportunities to assess and compare interactions within home ranges and, even, core areas across seasons and ecosystems. At distances < 5 km, hyenas mostly avoided lions, whereas lions either moved in the direction of hyenas, or showed random movements. Among intraspecific pairs, lion dyads demonstrated a high occurrence of coordinated movements, whereas hyenas mostly avoided each other at close distances, with some individuals tracking others (or moving in a shared direction) at large distances. Conclusions Dynamic interactions among sympatric lions and spotted hyenas illuminates how hyenas effectively reduce their potential of interactions with lions by utilizing spatiotemporal partitioning strategies, and local reactive avoidance behaviours within shared space-use areas. Insight into the drivers shaping the spatiotemporal patterns enabling species co-existence among apex predators is essential to understanding the behavioural choices made by members of a guild that subsequently affects population dynamics and community structure of multi-species food webs. Knowledge of such processes can contribute towards informed management strategies for the effective conservation of multi-predator systems.

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