Unlocking the Conservation Potential of Managed Timberlands Through Understanding Avian Community Dynamics

Abstract

This study investigates avian community composition across different forest stand stages within managed pine landscapes of the southeastern United States. It addresses two key research questions: (1) How do avian species richness and community composition vary across different successional stages within managed pine landscapes in the southeastern U.S.? and (2) How do stand-scale characteristics and landscape-scale features influence avian diversity in managed timberlands? A total of 69 bird species were documented, with natural stands supporting the highest species richness (55 species), followed by emergent and mature stands. The most abundant habitat-use groups were edge specialists and generalists, while insectivores dominated dietary guilds, accounting for 71.6% of detections. Among migration groups, non-migratory residents comprised 55% of detections, with long-distance migrants at 28% and short-distance migrants at 17%. Statistical analyses, including Jaccard Similarity Indices and PERMANOVA, revealed significant differences in bird community composition among stand stages, particularly between pre-thinned, natural, and emergent stands. Non-metric Multidimensional Scaling (NMDS) indicated that habitat structure and land cover characteristics—such as basal area, tree density, and herbaceous cover—strongly influenced avian community composition. These findings highlight the importance of both stand-scale and landscape-scale environmental gradients in shaping bird communities. An Indicator Species Analysis (ISA) identified 16 indicator species across stand stages, with mature and emergent stands supporting the highest numbers. Notably, the Blue Grosbeak, Common Yellowthroat, and Yellow-breasted Chat emerged as strong indicators of emergent habitats. Species Distribution Models (SDMs) for these species highlighted grassland-herbaceous cover, basal area, and proximity to water as key predictors of habitat presence. Jackknife analyses further confirmed the importance of vegetation structure and landscape features, with logistic regression models demonstrating classification accuracies ranging from 68.6% to 95.2%. Overall, this study underscores the significant influence of stand stage on avian community structure and habitat preferences. The results emphasize the ecological importance of natural and emergent stands in maintaining bird diversity, particularly for species associated with early successional and structurally complex habitats. These findings provide critical insights for forest management and conservation planning, supporting strategies aimed at promoting avian biodiversity across working timberlands.