Dark Nights, Safe Flights: How Turning Off Lights Helps Migrating Birds

Many songbirds migrate at night and are drawn to artificial light. Scientists have estimated between 365 million and 988 million birds die each year in collisions with buildings in the United States, and conservation groups often use a rounded figure of about a billion when describing the global scale. Bright lights can trap and disorient birds while they fly, and younger birds may be especially vulnerable. Forecasting tools like BirdCast have been developed to predict heavy migration nights, and these forecasts have been used to schedule Lights Out actions.

Cities such as Chicago, Toronto and New York have implemented Lights Out programs; building exteriors and interior non-essential lighting are dimmed or turned off on high-risk nights. Turning lights off from 11 p.m. to 6 a.m. has been recommended in many campaigns, and simple measures such as closing curtains, shielding outdoor lights, or using motion sensors are often promoted. While architects are adopting bird-friendly glass and designs, individuals can still help by reducing light at night and reporting collisions to monitoring projects. Therefore, local groups and city officials publish migration forecasts and ask residents to follow simple steps on predicted nights.