The short-term effects of wildfire on heathland bird communities: a case study at Killarney National Park, Ireland

Thomas Robert Howells , Kilian Kelly, Tom Gittings, Patrick Gleeson, Siún Ní Cheallaigh, Rachel Dowling, Eoghan Phelan, Joanne Monaghan, Domonkos Boka, Christina Maloney, Tom Siekaniec, Jaimie Maidwell, Chloe Payne, David Rees, Claire Deasy, Darren M. Evans

Fire is a key driver of ecosystem structure and function globally, yet climate and land-use change are driving increasingly variable wildfire patterns, with important consequences for biodiversity and ecological processes. Post-fire community dynamics are shaped by ecological, landscape and fire characteristics, but as these drivers change, understanding avian community-level responses is critical for predicting post-fire trajectories, ecosystem resilience and informing management.

Temperate heathlands are of high conservation and cultural value but face increasing wildfire risk. Following a major wildfire in Killarney National Park, Ireland, in 2021, we set out to understand and quantify the impacts on upland bird abundance, behaviour, species richness and community composition using a paired burnt-unburnt experimental design over the subsequent three year period.

Bird abundance and species richness were significantly reduced in burnt areas during the first two years, although community composition remained broadly unchanged. Burnt sites supported a reduced subset of the same species present in unburnt areas, indicating density reductions without species turnover. This pattern suggests a degree of short-term community resilience, with species persisting despite reduced local abundance. Species-specific responses also suggested potential shifts in territorial behaviour, with increased singing activity by meadow pipits (Anthus pratensis) across burnt sites despite reduced abundance. By the third year, differences between burnt and unburnt plots weakened, suggesting the start of a recovery of the bird communities.

These findings suggest that wildfire strongly affects local bird abundances in the short-term without immediately restructuring communities, with recovery likely mediated by habitat regeneration, resource dynamics and behavioural plasticity. Assessing recovery to the pre-wildfire community state requires long-term monitoring, as effects on upland birds are likely to depend on burn extent and severity, together with other context-specific factors.