A continental system for forecasting bird migration

Billions of animals cross the globe each year during seasonalmigrations, but efforts tomonitor them are hampered by the unpredictability of their movements.We developed a bird migration forecast system at a continental scale by leveraging 23 years of spring observations to identify associations between atmospheric conditions and bird migration intensity.Our models explained up to 81% of variation in migration intensity across the United States at altitudes of 0 to 3000 meters, and performance remained high in forecasting events 1 to 7 days in advance (62 to 76% of variation was explained). Avian migratory movements across the United States likely exceed 500 million individuals per night during peak passage.Bird migration forecasts will reduce collisions with buildings, airplanes, andwind turbines;informa variety ofmonitoring efforts;and engage the public.