Moving to stay in place: behavioral mechanisms for coexistence of African large carnivores

Abstract

Most ecosystems have multiple predator species that not only compete for shared prey, but also pose direct threats to each other. These intraguild interactions are key drivers of carnivore community structure, with ecosystem-wide cascading effects. Yet, behavioral mechanisms for coexistence of multiple carnivore species remain poorly understood. The challenges of studying large, free-ranging carnivores have resulted in mainly coarse-scale examination of behavioral strategies without information about all interacting competitors. We overcame some of these challenges by examining the concurrent fine-scale movement decisions of almost all individuals of four large mammalian carnivore species in a closed terrestrial system. We found that the intensity ofintraguild interactions did not follow a simple hierarchical allometric pattern, because spatial and behavioral tactics of subordinate species changed with threat and resource levels across seasons. Lions (Panthera leo) were generally unrestricted and anchored themselves in areas rich in not only their principal prey, but also, during periods of resource limitation (dry season), rich in the main prey for other carnivores. Because of this, the greatest cost (potential intraguild predation) for subordinate carnivores was spatially coupled with the highest potential benefit of resource acquisition (prey-rich areas), especially in the dry season. Leopard (P. pardus) and cheetah (Acinonyx jubatus) overlapped with the home range of lions but minimized their risk using fine-scaled avoidance behaviors and restricted resource acquisition tactics. The cost of intraguild competition was most apparent for cheetahs, especially during the wet season, as areas with energetically rewarding large prey (wildebeest) were avoided when they overlapped highly with the activity areas of lions. Contrary to expectation, the smallest species (African wild dog, Lycaon pictus) did not avoid only lions, but also used multiple tactics to minimize encountering all other competitors. Intraguild competition thus forced wild dogs into areas with the lowest resource availability year round. Coexistence of multiple carnivore species has typically been explained by dietary niche separation, but our multi-scaled movement results suggest that differences in resource acquisition may instead be a consequence of avoiding intraguild competition. We generate a more realistic representation of hierarchical behavioral interactions that may ultimately drive spatially explicit trophic structures of multi-predator communities.

Living on the edge: Multiscale habitat selection by cheetahs in a human‐wildlife landscape

“…However, studies in other parts of Africa have found a much higher cub survival, even with the presence of lions (e.g., Mills & Mills, 2013). Additionally, recent research has shown that lion numbers do not negatively influence cheetah numbers (Swanson et al., 2014), which is likely because cheetahs adjust their spatiotemporal patterns on a fine scale to avoid immediate risks of these larger, more dominant carnivores (Broekhuis et al., 2013; Vanak et al., 2013). We found that cheetahs preferred areas dominated by semiclosed habitat which could explain why cheetahs preferred the wildlife areas despite the very high lion densities (Elliot & Gopalaswamy, 2017).…”

Spatio-temporal interactions facilitate large carnivore sympatry across a resource gradient

“…For example, African wild dogs Lycaon pictus move over large distances in search of habitats where they can avoid the competitively dominant lions and hyaenas, which are known to steal their kills [40]. Under scenarios of intensive interspecific competition, a dominant competitor's presence may result in avoidance of resource-rich habitats by subordinate competitors [4]. Our results show evidence of such fine-scale avoidance behaviours in one high carnivore density reserve (Nagarahole), but not in the other (Bandipur; table 5 and figure 3).…”

“…aggression [4]. Adaptations that facilitate intra-guild sympatry may be more pronounced as competition within the guild intensifies [9] through 'character displacement' (sensu [10]).…”

A spatial theory for characterizing predator–multiprey interactions in heterogeneous landscapes

“…That is, our approach is designed to allow consideration of a wider range of landscape configurations than the square or rectangular domains such as those used in classical models of spatially explicit dynamical systems [1]. For example, our approach allows for fine-scale assessments of the behavioural response of animals to non-regular habitat edges resulting from natural disturbances due to extreme weather events or fire, or human activities [27]. Our approach allows for the entire landscape domain V to be subdivided into i different land cover or land use Figure 1.…”