This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2009 under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The fellowship supports a research and training plan entitled "Algorithms for changing species distributions: tracking the world's tree swallows" for Daniel Sheldon. The host institution for this research is Oregon State University, and the sponsoring scientist is Thomas Dietterich.
Understanding the geographical distributions of species and how they change is critical to conservation, ecological science, and global climate change research. This research develops computational methods to quantify patterns of change in the distribution of the Tree Swallow (Tachycineta bicolor), a migratory songbird that forms dense communal roosts during its eight-month non-breeding season. The early-morning departure of birds from the roost creates a distinctive "roost ring" pattern that is visible in NEXRAD weather radar images. The project employs techniques from computer vision, machine learning and probabilistic modeling to automatically detect and extract roost rings from radar, assembles daily estimates of the distribution of Tree Swallows throughout the United States, and then infers the patterns of migration and other events that cause distribution changes over time, both short-term and long-term. One of the great assets of NEXRAD radar is the ability to look fifteen years into the past with archived data. This project addresses significant questions about the roosting biology and population trends of swallows, advances techniques in radar ornithology, and lays an algorithmic foundation for identifying patterns of change in species distributions.
Training objectives include strengthening skills in computer vision, radar ornithology, and species distribution modeling. This research engages a broad audience of biologists, computer scientists, conservationists, and the general public by providing a complete and accurate model of songbird distribution on a large scale, with provisions to continuously monitor changes for the past fifteen years and into the future.
