Investigating the Potential Consequences of Woodland Creation for British Mammal Populations

ABSTRACT Background Woodland creation is a key target in many countries in order to achieve carbon sequestration targets and provide other benefits, such as improved provision of ecosystem. However, we currently lack an understanding of how ambitious woodland creation targets will affect wildlife conservation at a large spatial scale. Aims We aimed to predict how current and target woodland creation will affect British mammal populations. Materials & Methods We simulated the conversion of suitable areas to woodland and, based on knowledge of their ranges and population density, assessed how this would affect habitat availability and population size for 27 species (excluding bats) from 2023 to 2050. These simulations used assumed ratios of coniferous and broadleaf woodland creation derived from recent tree planting statistics. Results & Discussion If woodland creation targets for England, Scotland and Wales (2609, 4800 and 1800 km 2 respectively) were to be achieved, we predict that mammal species included in this study would have a median change in population size across the UK of 7.3% (range = −8.7% to 31.4%) between 2023 and 2050. Rodents and ungulates had the most species with predicted population gains, whilst lagomorphs all exhibited population declines. The predicted magnitude of habitat loss or gain was higher for policy targets compared to the continuation of current planting rates. Nonetheless, under current planting rates, some woodland‐dependent species, such as the Pine Marten, were predicted to gain up to 15% of suitable habitat area within their current range. Conclusion These results highlight the opportunities presented by woodland creation to improve the conservation status of British mammals. That said, gains were not universal, and for grassland‐dependent species, expansion of woodland could reduce habitat availability and increase fragmentation within already restricted ranges. Our analyses provide a starting point from which to direct field‐based studies into local responses of mammals to woodland creation.