Logging and thinning generate distinct post-management vegetation conditions that shape bird communities

Abstract

This study examined contrasting post-management vegetation conditions and bird-community responses following logging and thinning in managed forests. Bird surveys were conducted at 34 sites across three regions in South Korea from August 2022 to May 2025. Sites represented four management categories defined by forestry practice and time since management: one year and 10 years after logging (L1 and L10) and thinning (T1 and T10). Vegetation variables were summarized using Factor Analysis of Mixed Data (FAMD), and plant and bird species were classified into functional guilds. Generalized linear mixed models (GLMMs) evaluated plant guild responses and plant–bird guild linkages, while linear mixed-effects models, dynamic occupancy models, and species-level GLMMs assessed bird diversity, occurrence dynamics, and species responses. FAMD identified distinct vegetation gradients among the four management categories. Early logged stands were characterized by greater ruderal plant richness and a stronger representation of edge-associated birds, whereas thinned stands, particularly T1, supported greater richness of hole-nesting and interior-associated bird guilds. All three bird-diversity indices declined with increasing Str3, a vegetation-structure gradient representing greater development of lower- to mid-layer vegetation, while species richness additionally declined with increasing Plant2. Species-level models further supported these guild-level patterns, indicating that bird responses were associated with integrated changes in vegetation structure and composition rather than with forestry type alone. Overall, logging and thinning were associated with contrasting post-management vegetation conditions, with consequences for plant and bird community organization. Maintaining a mosaic of vegetation conditions across managed forests may help conserve functionally diverse bird communities.