Seasonal microbiome dynamics of Eastern honey bee and its predator, the Asian hornet: ecological interactions, prey–predator microbial transfer, and implications for economic entomology

Abstract The present study provides the first comparative seasonal profiling of bacterial and fungal communities in Eastern honey bee (Apis cerana Fabricius, 1793) and their predator, the Asian hornet (Vespa velutina Lepeletier, 1836), collected from the same location in southern China. Using a combined 16S, 18S, and ITS (internal transcribed spacer) amplicon sequencing approach, we characterized the microbiomes of both species across mid-season (August) and late-season (November) timepoints. In honey bees, core bacterial genera including Lactobacillus and Gilliamella exhibited clear seasonal shifts, with Lactobacillus increasing from 20% (median: 53.4%) in mid-season to 64% (median: 53.4%) in late season, consistent with previously reported overwintering-associated microbiome changes. Fungal communities were dominated by Cladosporium in mid-season (40%), with fermentative yeasts including Zygosaccharomyces and Metschnikowia emerging in the late season. Hornet microbiomes, shaped by an omnivorous diet, exhibited a marked seasonal transition from Acinetobacter in mid-season to Erwinia dominance (58%) in late season. The detection of bee-associated taxa such as Gilliamella in hornet samples (10% in mid-season) suggests possible trophic-mediated microbial transfer, though experimental confirmation is required. These findings expand ecological understanding of pollinator–predator interactions and highlight seasonal microbiome dynamics that may inform future research on pollinator health and ecological interactions. We additionally note methodological considerations regarding sequencing platform selection that may be relevant for researchers designing similar studies.