The Birds of the Air

Osprey, swans, Canada geese, ducks — plus all sorts of songbirds: We know they’re distant travelers even now on the move. Now we can follow the paths of their journeys.
    For the first time, scientists have documented the migratory year 118 species birds follow throughout the Western Hemisphere.
    The animated image shows us how and when these species make their flights north and south. The map can be switched to show which species are on the move, as well as the time of year they begin their annual trip.
    The Cornell Lab of Ornithology map is based on millions of birding observations recorded on the citizen science website eBird, a database inviting everyday people to record their bird observations. Researchers concluded that a combination of geographic features and atmospheric conditions influence the routes birds follow during spring and fall migration.
    A key finding: Birds that head out over the Atlantic Ocean during fall migration, heading to the Caribbean and South America, follow a clockwise loop. On their return trip, they take a path farther inland. These looped paths suggest the birds are taking advantage of atmospheric conditions, using headwinds and trade winds to their benefit.
    The spring migration route is more roundabout, but the birds travel faster thanks to the strong tailwinds as they head north.
    Knowing more about migration can aid conservation efforts on the ground, such as knowing where to place wind turbines or when to light tall buildings to prevent bird deaths at night. Accurate migration models also help researchers understand migration timing and pathways, how they respond to climate change and whether there are links between variation in migration timing and changes in population size.
    See it yourself: http://bit.ly/BayWeekly_Migration. Then send us your photos of birds on the wing.