This project, led by Jeffrey Buler of the University of Delaware with a number of colleagues, fills a key gap in our understanding of stopover habitat for migratory landbirds. It provides a large-scale perspective on important sites for migrants across multiple states in the Eastern U.S. Using innovative analyses of weather radar data to detect migrating birds, coupled with field surveys, the reports make predictions about the importance of sites for migrants across the Northeast and Mid-Atlantic U.S. “Importance” is defined here by the relative number of birds that stop over throughout the migratory season and how consistently birds depart sites from day to day. Areas with the highest and most consistent bird densities are considered to be of greatest stopover importance.