Biology subjects

Marsh, K. J.

Publications and source records attributed to Marsh, K. J..

2 recordsLinked to original sources

bioRxiv2025

Microbiome Dynamics During Translocation of the Critically-Endangered Frog Craugastor ranoides

O_LIAmphibian populations are declining and species going extinct due to habitat loss, climate change and emerging infectious disease, prompting the increasing use of translocations as a conservation tool. C_LIO_LISkin-associated microbial communities play a key role in amphibian health, particularly in protecting hosts from pathogenic infection. However, to date we know relatively little about the impact of translocation on the dynamics of skin-associated microbes, or the consequences of translocation-mediated disturbance of the microbiome for amphibian health. C_LIO_LIWe investigated the skin microbiome of the critically endangered frog Craugastor ranoides, now restricted to a fraction of its historical range in Costa Rica. We first conducted a multi-population survey to characterise among-population variation in skin bacterial communities. We then translocated individuals to a new site, using radio tracking to monitor them over time and assess individual-level changes in body mass, microbiome composition, and predicted microbial function. C_LIO_LIWe found limited among-population variation in skin microbiome composition across three different populations of C. ranoides. Response of the microbiome to translocation was highly individual-specific; some frogs demonstrated relatively stable community richness and composition, whilst others exhibited marked turnover in bacterial membership and predicted function. Body mass showed similar dynamics, but several of the recaptured frogs had gained mass after several days in the translocation site. C_LIO_LISynthesis and Applications: Our findings highlight the importance of considering microbiome dynamics in threatened species translocations to optimize individual health. This includes considering whether individuals should be prioritised for translocation based on their initial microbiome composition, and understanding how shifts in microbiome post-translocation may alter overall success of translocation efforts. These insights extend beyond amphibians, offering a broader framework for integrating long-term monitoring of host microbiomes and health into conservation efforts. C_LI

ecology↗

bioRxiv2021

Synchronous seasonality in the gut microbiota of wild wood mouse populations

O_LIThe gut microbiome performs many important functions in mammalian hosts, with community composition shaping its functional role. However, what factors drive individual microbiota variation in wild animals and to what extent these are predictable or idiosyncratic across populations remains poorly understood. C_LIO_LIHere, we use a multi-population dataset from a common rodent species (the wood mouse, Apodemus sylvaticus), to test whether a consistent set of core gut microbes is identifiable in this species, and to what extent the predictors of microbiota variation are consistent across populations. C_LIO_LIBetween 2014 and 2018 we used capture-mark-recapture and 16S rRNA profiling to intensively monitor two wild UK mouse populations and their gut microbiota, as well as characterising the microbiota from a laboratory-housed colony of the same species. C_LIO_LIAlthough broadly similar at high taxonomic levels and despite being only 50km apart, the two wild populations did not share a single bacterial amplicon sequence variant (ASV). Meanwhile, the laboratory-housed colony shared many ASVs with one of the wild populations from which it is thought to have been founded decades ago. Despite strong taxonomic divergence in the microbiota, the factors predicting compositional variation in each wild population were remarkably similar. We identified a strong and consistent pattern of seasonal microbiota restructuring that occurred at both sites, in all years, and within individual mice. While the microbiota was highly individualised, seasonal convergence in the gut microbiota among individuals occurred in late winter/early spring. C_LIO_LIThese findings reveal highly repeatable seasonal gut microbiota dynamics across distinct populations of this species, despite divergent taxa being involved. Providing a platform for future work to understand the drivers and functional implications of such predictable seasonal microbiome restructuring, including whether it might provide the host with adaptive seasonal phenotypic plasticity. C_LI

ecology↗