Quantifying Vulnerability of Quaking Aspen Woodlands and Associated Bird Communities to Global Climate Change in the Northern Great Basin Completed

Quaking aspen populations are declining in much of the West due to altered fire regimes, competition with conifers, herbivory, drought, disease, and insect outbreaks. Aspen stands typically support higher bird biodiversity and abundance than surrounding habitat types, and maintaining current distribution and abundance of several bird species in the northern Great Basin is likely tied to the persistence of aspen in the landscape. This project examined the effects of climate change on aspen and associated bird communities by coupling empirical models of avian-habitat relationships with landscape simulations of vegetation community and disturbance dynamics under various climate change scenarios. Field data on avian abundance, stand age structure, and other vegetation characteristics will be combined with existing spatial data sets. Key questions that were examined include: (1) what is the current successional, structural, and spatial distribution of aspen on the landscape, and how do these factors affect abundance of bird species; (2) how have aspen stand condition and distribution, and avian abundance and distribution, been shaped by disturbance (e.g., grazing and fire); (3) how is global climate change likely to affect aspen condition and distribution, and what are the implications for avian species; and (4) how are today’s management strategies, or adaptive adjustments to those strategies, likely to affect long-term risks and persistence of aspen and associated avian communities.