When bigger isn’t better—Implications of large high?severity wildfire patches for avian diversity and community composition

Aim Wildfires increasingly create large high-severity patches with interior areas far from less disturbed habitats. We evaluated how these trends impact bird communities by investigating the effect of internal distance lower-severity areas, patch size, and years since fire on avian alpha beta diversity. Location Sierra Nevada, California, USA. Methods Bird occurrence data were collected during 2009–2017 within 27 wildfires representing 1–30 disturbance. A two-step multispecies occupancy method was used to account for imperfect detection 94 species estimate effects characteristics community richness dissimilarity. Results Community decreased edge size. Richness increased fire, but this pattern dependent higher peak (23 species) near edges than interiors (18 species). dissimilarity not associated distance, indicating that contain subsets of, rather complements to, communities. Dissimilarity peaked later increasing Guild tree primary cavity nesters negatively ground shrub insensitive while nester somewhat Due declines among other species, made up a greater percentage patches. Main conclusions As activity increases due accumulating forest fuels accelerating climate change, their resulting early-seral habitats are becoming more extensive area. Such changes likely decrease diversity locally shift composition away forest-associated species. Management actions promote full range limit size may best conserve fire-adapted ecosystems.