| dc.description.abstract | Species declines are both widespread and worsening, and climate change is predicted to become one of the biggest drivers. Populations living at the edge of species’ distributional ranges are projected to be particularly vulnerable under future climate change scenarios. Life history strategies, such as dormancy, will play a role in how variation in species resilience and persistence, especially in non-typical habitats at the peripheries of their range, becomes manifest. Energy conservation strategies, such as dormancy, might gain particular significance in the context of a changing climate, potentially affording individuals of some species a competitive advantage. Understanding the energetic and ecological requirements of species, particularly those at the range margins, is likely to become more useful for effective conservation.
In this thesis, I have investigated the patterns, drivers, and consequences of daily torpor use in populations of hazel dormice Muscardinus avellanarius in Britain. I have then assessed how this behaviour might change in response to climate change, and what the implications are for dormouse populations. I evaluate new tools for effective conservation of dormice in marginal landscapes by testing species distribution models at different resolutions. I then explore dormouse ecological requirements in these landscapes through dietary analysis.
My study reveals that rates of daily torpor are influenced by factors such as the presence of ancient woodland, connectivity of broadleaf habitat, geographic location, and climate. I reveal relationships between torpor, dormouse abundance, and breeding events, directly impacting population dynamics.
I then predict the future frequencies of daily torpor in Britain. Projections suggest a reduction in torpor use as local climatic conditions change, potentially leading to increased fecundity among dormouse populations in England and Wales. However, under worst-case climate scenarios, elevated torpor rates are expected in certain years, posing a risk to small populations, especially those at the distributional edge. Conservation strategies should focus on preventing declines at range margins, fostering resilience, and averting range constriction.
At a landscape scale, I examined the accuracy of predicting dormouse distribution in non-typical habitats, particularly conifer plantations at the edge of their range in North Wales. Regional and national species distribution models could not accurately predict dormouse presence in non-typical habitat, highlighting the need for increased knowledge of dormouse subsistence in conifer plantation.
At a finer-scale, I investigate the persistence of dormouse populations in conifer plantations at the edge of their range. I conducted stable isotope analysis to compare diets between non-typical and optimal habitats. Results indicate varying niche breadths among dormouse populations, with the ability to subsist on a restricted diet in coniferous habitats. The study highlights site-specific food sources, including invertebrates, and underscores the importance of plant diversity and high invertebrate numbers in conservation management.
Finally, I collated the findings of this thesis and discuss them within the context of edge of range populations and future threats from climate change. My work aids understanding of hazel dormice energy budgets, habitat requirements, and diets, offering diverse conservation recommendations, particularly in the face of ongoing climate change. | en_GB |
