Ecological Traits and Intraguild Competition Mediate Spatial and Temporal Overlaps Among Sympatric Mesocarnivores

In terrestrial mammalian carnivore guilds, interspecific competitions (interferences and resource competitions) among sympatric species induce their ecological and behavioral patterns and population dynamics, thereby shaping community structures. Competitive species must partition their ecological niches for sympatry, while the extent of niche overlaps is mediated by either the ecological traits (e.g., body size differences) or environmental features. We aimed to elucidate the patterns of spatial and temporal niche overlaps in mesocarnivore guilds, which are mediated by their ecological traits, regional environments, and anthropogenic disturbances. We investigated the spatial occurrence and diel activities of six mesocarnivore species and estimated their spatial and temporal overlap indices in various landscapes with different anthropogenic disturbances in central Bulgaria. Statistical modeling demonstrated that spatial overlap among mesocarnivores declined when mesocarnivore pairs were within the same family and when large carnivores (particularly wolves, Canis lupus) were present. Furthermore, we found that the extent of their temporal overlaps was associated with taxonomic and body size differences in mesocarnivore pairs as well as their trophic competitions. Our findings indicated that the intensity of interferences among mesocarnivore species was key for the decline of spatial or temporal niche overlap to relax antagonistic interactions.