Climate Change Impact on Small Mammal Distribution

Climate change is reshaping the geographic distributions of small mammals across terrestrial ecosystems, with cascading consequences for biodiversity, ecosystem function and human welfare. Rising air and soil temperatures, shifts in precipitation regimes and changes in snow cover alter habitat suitability and resource availability, driving range contractions, expansions and shifts in species assemblages. Species’ intrinsic traits such as body size, diet breadth, reproductive rate and dispersal capacity interact with anthropogenic pressures including land-use change and habitat fragmentation to determine vulnerability or resilience. Cold-adapted specialists often retreat to high elevations or latitudes where microclimatic refugia persist, while generalist and smaller-bodied species may exploit novel habitats, leading to reorganisation of community structure. Fine-scale heterogeneity in microclimate conditions can buffer or amplify regional climate trends, highlighting the need to integrate sub-habitat thermal variability into predictive models. Advances in mechanistic modelling, genetic analysis and long-term monitoring are improving forecasts of distributional responses under future scenarios, informing conservation strategies that aim to maintain connectivity corridors, protect key refugia and anticipate emergent species interactions.

Research from Nature Portfolio

Recent studies have quantified the global patterns and drivers of range dynamics in terrestrial mammals, revealing that over half of the species examined have lost part of their historical distribution, while a smaller subset have expanded. Large-bodied species and those in regions experiencing significant temperature increases and habitat degradation are most prone to contraction, whereas small, fast-reproducing generalists are more likely to broaden their ranges. This work emphasises the interplay between life-history traits and anthropogenic pressures in shaping distributional outcomes and underscores the importance of incorporating both climatic and human factors into models that predict future changes.

Climate Change Impact on Small Mammal Distribution publication trend

The graph below shows the total number of articles in climate change impact on small mammal distribution across all publications each year (not limited to Nature Index journals).

Technical terms

Range contraction: A reduction in the area occupied by a species over time.

Bioclimatic envelope: The set of climatic conditions that define the suitable environment for a species.

Microrefugia: Small-scale habitat features where local conditions buffer organisms from broader climate extremes.

Species distribution model (SDM): A computational method that relates species occurrence data to environmental variables to predict geographic distributions.

Thermal niche: The range of temperatures within which a species can maintain physiological performance and population persistence.

References

1. Global correlates of range contractions and expansions in terrestrial mammals. Nature Communications (2020).
2. The Importance of Biologically Relevant Microclimates in Habitat Suitability Assessments. PLOS ONE (2014).
3. Anthropogenic refugia ameliorate the severe climate-related decline of a montane mammal along its trailing edge. Proceedings of the Royal Society B (2012).
4. Predicted Shifts in Small Mammal Distributions and Biodiversity in the Altered Future Environment of Alaska: An Open Access Data and Machine Learning Perspective. PLOS ONE (2015).
5. Variation in subsurface thermal characteristics of microrefuges used by range core and peripheral populations of the American pika (Ochotona princeps). Ecology and Evolution (2017).