Understanding Changes in Wood Thrush and Ovenbird Populations in Virginia—The Role of Forest Fragmentation and Connectivity

Aim: Yearly summaries of the North American Breeding Bird Survey (BBS) indicate that populations many bird species are in decline. Determining causes these declines is focus much current research avian conservation. Forest fragmentation has been linked to species. In this study, effects forest and connectivity as well slope physiographic features on two migratory explored. Location: This study area Virginia, USA. Taxon: The focused Wood Thrush (Hylocichla mustelina) Ovenbird (Seiurus aurocapilla). Methods: We used Markov Chain Monte Carlo Generalized Linear Mixed Models (MCMCglmm) package with a Poisson distribution Bayesian data analysis model 95% probability interval. Using Repeated Measures ANOVA, independent treatment variables included time at 3 different levels 2001, 2006 2011; three types—Core, Connected Fragmented; 8 categories 5 regions. Results: Results significant impact population sizes Ovenbirds Virginia recent changes Virginia’s landscape have had negative impacts Specifically, characteristics influence rates urbanization correlated populations. Coastal Plain region contributes significantly both currently. Main Conclusions: Core forests areas decline process affects distributions thrush state.