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Abstract Interactions among terrestrial carnivores involve a complex interplay of competition, predation and facilitation via carrion provisioning, and these negative and positive pathways may be closely linked. Here, we developed an integrative framework and synthesized data from 256 studies of intraguild predation, scavenging, kleptoparisitism and resource availability to examine global patterns of suppression and facilitation. Large carnivores were responsible for one third of mesocarnivore mortality (n = 1,581 individuals), and intraguild mortality rates were superadditive, increasing from 10.6% to 25.5% in systems with two vs. three large carnivores. Scavenged ungulates comprised 30% of mesocarnivore diets, with larger mesocarnivores relying most heavily on carrion. Large carnivores provided 1,351 kg of carrion per individual per year to scavengers, and this subsidy decreased at higher latitudes. However, reliance on carrion by mesocarnivores remained high, and abundance correlations among sympatric carnivores were more negative in these stressful, high‐latitude systems. Carrion provisioning by large carnivores may therefore enhance suppression rather than benefiting mesocarnivores. These findings highlight the synergistic effects of scavenging and predation risk in structuring carnivore communities, suggesting that the ecosystem service of mesocarnivore suppression provided by large carnivores is strong and not easily replaced by humans.
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Droughts reshape apex predator space use and intraguild overlap
Abstract Droughts are increasing in frequency and severity globally due to climate change, leading to changes in resource availability that may have cascading effects on animal ecology. Resource availability is a key driver of animal space use, which in turn influences interspecific interactions like intraguild competition. Understanding how climate‐induced changes in resource availability influence animal space use, and how species‐specific responses scale up to affect intraguild dynamics, is necessary for predicting broader community‐level responses to climatic changes.Although several studies have demonstrated the ecological impacts of drought, the behavioural responses of individuals that scale up to these broader‐scale effects are not well known, particularly among animals in top trophic levels like large carnivores. Furthermore, we currently lack understanding of how the impacts of climate variability on individual carnivore behaviour are linked to intraguild dynamics, in part because multi‐species datasets collected at timescales relevant to climatic changes are rare.Using 11 years of GPS data from four sympatric large carnivore species in southern Africa—lions (Panthera leo), leopards (Panthera pardus), African wild dogs (Lycaon pictus) and cheetahs (Acinonyx jubatus)—spanning 4 severe drought events, we test whether drought conditions impact (1) large carnivore space use, (2) broad‐scale intraguild spatial overlap and (3) fine‐scale intraguild interactions.Drought conditions expanded space use across species, with carnivores increasing their monthly home range sizes by 35% (wild dogs) to 66% (leopards). Drought conditions increased the amount of spatial overlap between lions and subordinate felids (cheetahs and leopards) by up to 119%, but only lion‐cheetah encounter rates were affected by these changes, declining in response to drought.Our findings reveal that drought has a clear signature on the space use of multiple sympatric large carnivore species, which can alter spatiotemporal partitioning between competing species. Our study thereby illuminates the links between environmental change, animal behaviour and intraguild dynamics. While fine‐scale avoidance strategies may facilitate intraguild coexistence during periodic droughts, large carnivore conservation may require considerable expansion of protected areas or revised human‐carnivore coexistence strategies to accommodate the likely long‐term increased space demands of large carnivores under projected increases in drought intensity.
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- Award ID(s):
- 2337405
- PAR ID:
- 10611097
- Publisher / Repository:
- British Ecological Society
- Date Published:
- Journal Name:
- Journal of Animal Ecology
- Volume:
- 93
- Issue:
- 11
- ISSN:
- 0021-8790
- Page Range / eLocation ID:
- 1785 to 1798
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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