Microbiome Stability in Wild and Rehabilitated Insectivorous Bats Revealed by Shotgun Metagenomics

Wildlife rehabilitation can alter host-associated microbial communities, yet the effects of temporary managed care on the gut microbiome of insectivorous bats remain poorly understood. We used shotgun metagenomic sequencing to investigate gut microbiome composition in wild and rehabilitated bats from Yorkshire, United Kingdom. A total of 25 faecal metagenomes were analysed from four bat species (Myotis daubentonii, Pipistrellus pipistrellus, Nyctalus noctula, and Nyctalus leisleri), including wild baseline individuals and bats undergoing temporary managed care for 1-49 days. Microbial community structure clustered primarily according to host species and roost location, with no significant separation associated with rehabilitation status. Among bats in managed care, bacterial alpha diversity did not differ significantly with time in care (H = 2.30, p = 0.32). Archaeal communities displayed markedly lower interindividual variation than bacterial communities (coefficient of variation: 12.2% vs. 41.8%), indicating a highly conserved archaeal microbiome across hosts. Rehabilitated bats exhibited modest compositional shifts in bacterial communities, including increased relative abundances of Yersiniaceae and Lactobacillaceae and reduced abundances of environmentally associated taxa such as Pseudomonadaceae and Erwiniaceae. These changes may reflect controlled dietary provision and reduced environmental exposure during care. Overall, no marked rehabilitation-associated differences in gut microbiome diversity or community structure were detected under the current sampling design. These findings are consistent with microbiome stability during temporary managed care, although longitudinal studies are required to confirm microbiome dynamics within individual bats. Nonetheless, this study provides an initial baseline for future microbiome-informed wildlife rehabilitation studies.