The removal of apex predators can intensify interspecific competition among mesopredators, challenging stable coexistence. Identifying the mechanisms that resolve this competition is critical. We investigated this situation in Hainan Tropical Rainforest National Park, China, a system where the apex predator, clouded leopard (Neofelis nebulosa) has been absent for decades. Using camera-trap data from 88 sites, we first quantified the potential for exploitative competition among the three dominant mesopredators, the Asian palm civet (Paradoxurus hermaphroditus), the Chinese ferret-badger (Melogale moschata), and the leopard cat (Prionailurus bengalensis) by analyzing their diel activity patterns and, critically, their activity overlap with key prey species. We then evaluated their fine-scale spatial habitat selection as a compensatory coexistence mechanism. We identified a high potential for competition between the two most abundant mesopredators (Asian palm civet and Chinese ferret-badger), evidenced by a “dual-overlap” scenario: high pairwise activity overlap (Δ=0.87) coupled with high overlap with the same key nocturnal prey (Δ>0.86). In direct response to this pressure and constrained temporal options, these species exhibited pronounced spatial segregation. Occurrence of the Asian palm civet increased with elevation and canopy density, whereas that of the Chinese ferret-badger was associated more with proximity to roads. The leopard cat adopted another strategy by selecting rugged terrain. We conclude that in this depauperate guild, where divergence along the temporal niche axis is constrained, spatial habitat segregation emerges as the primary mechanism mitigating intense resource competition and enabling coexistence. Our findings suggest a context-dependent differentiation in niche axes and underscore that maintaining landscape heterogeneity is essential for conserving the integrity of such simplified carnivore communities lacking top predators.
Shi et al. (Wed,) studied this question.