Date of Award
24-3-2024
Document Type
Doctoral Thesis
Degree Name
Doctor of Philosophy
Department
Biological and Pharmaceutical Sciences
First Advisor
Dr. Peter Stuart
Second Advisor
Dr. Joanna Tierney
Third Advisor
Prof. Celia Holland
Abstract
The recent emergence of zoonotic pathogens such as, SARS-CoV-2, Ebola and Mpox, have emphasised the necessity to study wildlife and their pathogens. A knowledge gap currently exists in longitudinal studies of biological invasions, which are needed to understand the change in pathogen communities caused as the invader becomes more established. The invasion of Clethrionomys glareolus in Ireland provides a unique model system to study these changes at different stages of the bio-invasion. This is due to the depauperate small mammal community in Ireland, identifiable source population, introduction point, and ongoing expansion of C. glareolus in Ireland. Extensive work has been conducted to study the effects of the C. glareolus invasion on the native Apodemus sylvaticus. This present study has sampled over 1,000 rodents investigating bacterial and helminth communities of these rodents over four years, 2016, 2017, 2021 and 2022. Firstly, a dilution effect was observed in A. sylvaticus due to the increased presence of C. glareolus at the invasion core, for the bacteria, Mycoplasma haemomuris, and helminth species richness. Patterns consistent with “enemy release” were observed in the invasive C. glareolus, with both fewer bacterial and helminth species compared to their native range. However, the enemy release for Aspiculuris tianjinensis in C. glareolus observed in 2016 by Stuart et al., (2020), was found to be reversed when revisited, with higher abundances in the invasion front in 2021. Furthermore, increased prevalences of the protozoa family, Sarcocystidae, were observed in C. glareolus at the invasion front in Ireland. Finally, no effect of the C. glareolus invasion gradient was found for Leptospira, with both species found not to be significant reservoirs in Ireland. This study has observed different epidemiological patterns based on time and the stage of invasion compared to baseline studies, demonstrating that longitudinal studies are essential to fully understand biological invasions.
Recommended Citation
McManus, Andrew, "The invasive bank vole (Clethrionomys Glareolus); A longitudinal investigation into rodents and their pathogen communities, using the Irish Rodent Invasion as a model system." (2024). Theses [online].
Available at: https://sword.mtu.ie/allthe/856
Access Level
info:eu-repo/semantics/openAccess