We compared the reliability of visual diagnostic criteria to DNA diagnostic techniques, including newly designed primers, to discriminate Japanese marten (Martes melampus) feces from those of other sympatric carnivore species. Visual criteria proved > 95% reliable for fresh, odoriferous scats in good condition. Based upon this verification, we then examined if and how Japanese marten diet differs among seasons at high elevation study site (1500–2026 m). We also considered how intra-specific competition with the Japanese red fox (Vulpes vulpes japonica) may shape marten feeding ecology. From 120 Japanese marten fecal samples, high elevation diet comprised (frequency of occurrence) 30.6–66.0% mammals, 41.0–72.2% insects and 10.6–46.2% fruits, subject to seasonal variation, with a Shannon-Weaver index value of 2.77. These findings contrast substantially to seasonal marten diet reported in adjacent lowland regions (700–900 m), particularly in terms of fruit consumption, showing the trophic adaptability of the...

Major histocompatibility complex (MHC) genes encode proteins that play a key role in the adaptive immune system of vertebrates and are generally highly polymorphic for defence against various pathogens. To understand the diversity and evolution of MHC variation in badgers in the genus Meles (Carnivora, Mustelidae), we analysed sequence variation of the MHC class II DRB gene exon 2 in the Japanese (Meles anakuma), Asian (Meles leucurus), European (Meles meles) and Southwest Asian (Meles canescens) badgers. Variation was higher in the Meles species than in other species in Mustelidae, and altogether 60 alleles were isolated from 28 individuals. The variable number of three to eight putative alleles per individual was observed, indicating the presence of two to four DRB loci per haploid genome. Non-synonymous substitutions exceeded synonymous substitutions at putative antigen-binding sites. Selection analyses of PAML models, fixed-effect likelihood and mixed-effect model evolution, together with the single breakpoint recombination, indicated that recombination and selection could be responsible for driving and maintaining the diversity of Meles DRBs. In a phylogenetic analysis, the DRB sequences from Meles were distributed in several clusters, which were dispersed among sequences of other mustelid family, even five alleles comprised a monophyletic group of Meles DRBs within a canid clade. The data demonstrate trans-species polymorphisms at different taxonomic and temporal scales, transgressing family-, genus- and species-level splits. Some allele sequences were shared by two to four of the Meles species, in line with a close phylogenetic relationship among these species.

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.