When NASA scientists were looking for a site for their new portable Polarimetric Radar, which measures precipitation, they contacted the Nature Conservancy's Barry Truitt about moving the radar to a Conservancy property in Oyster, Virginia. Truitt, a conservation scientist, had his own ideas for the radar, so they struck a deal: On rainy days, NASA gathers precipitation data; on clear fall nights, the Conservancy tracks migrating birds along Virginia's Eastern Shore.
Millions of migrating songbirds stop along the shore to rest and forage before taking to the evening skies to continue their journeys. The radar picks up concentrations of migrants moving into the atmosphere, and Truitt and Sara Mabey, a conservation scientist at North Carolina State University, use this data to identify stopover habitats. Banding studies help confirm the information. "This will open up a whole other world of habitats that these birds are using," says Truitt, "and will help us prioritize areas for conservation."
The new radar is an improvement over the national network of weather radar that ornithologists have used for migration research for a decade. That radar can record the flight direction, speed and relative density of birds in the atmosphere; the newer radar can also determine the size and shape of targets. Mabey and Truitt hope to calibrate the new radar to identify the numbers and sizes of groups of birds, allowing the scientists to distinguish, for example, between songbirds and waterfowl.
"We don't really understand the big picture of dynamics of migration yet," says Mabey. "Weather-surveillance radar has great potential as a conservation tool, because it can help us see the long-term patterns and protect this phenomenon on a continental scale."