Millions of birds are expected to cross Oregon skies starting Friday night, and wildlife advocates are asking residents to do something simple to help them along: flip a switch. Per social media accounts tracking the migration, the flights will move through under cover of darkness, when most species prefer to travel.
The Bird Alliance of Oregon has asked people across the state to turn off unnecessary outdoor lighting and close their curtains or shades Friday night to keep migrating flocks from getting disoriented. Night travel is cooler and safer for birds making the long journey, and most species navigate by using the stars to set their course, according to the Bird Alliance of Oregon. The group explains that birds make this journey at night while “visualizing the magnetic pull of the earth and using the moon and stars to set their course.”
That reliance on natural light is exactly why artificial glow from cities poses such a danger. The Bird Alliance of Oregon warns that skyglow from brightly lit buildings can drown out the stars birds depend on, pulling disoriented flocks toward urban areas where the real trouble begins. Once lured in, birds can crash directly into windows or circle a lit building in confusion until they burn through the energy they need to keep migrating, the group says.
Why September Is Peak Migration Season
The timing lines up with what the Bird Alliance of Oregon calls the peak of fall migration, which the group pegs as running from September 19 through October 19, with a second peak each spring from April 15 through May 19. Nationally, more than 80% of North America's migrating birds travel at night. That same research estimates building collisions kill between 365 million and 988 million birds in the United States every year, and notes that artificial light alone can shift birds' migration schedules by as much as a week.
Alerts about the size of these nighttime flights have varied from one migration window to the next. Oregonlive reported an estimate of 2.9 million birds expected in the skies over Oregon during one night last September, while a spring alert cited by Here Is Oregon put the figure at roughly 7.4 million birds traveling the state's skies in a single night. Those forecasts come from BirdCast maps produced by Colorado State University and the Cornell Lab of Ornithology.
A Small Fix With a Track Record
The ask itself is straightforward: turn off outdoor lights and close curtains or blinds, as the Bird Alliance of Oregon has advised, or, as KOIN.com put it in reporting on Friday's migration, simply flip a switch and close the shades for the night. The payoff for that small effort has shown up elsewhere. The Bird Alliance of Oregon points to one Chicago building that took part in a Lights Out program and saw an 80 percent decrease in bird-strike rates.
Oregon is far from alone in running this kind of campaign. In Texas, the Audubon-coordinated Lights Out, Texas! initiative marks its own peak migration window from September 5 through October 29 and asks participants to turn off or dim nonessential lighting, according to Audubon Texas. That program was originally launched in spring 2020 but expanded statewide beginning in fall 2020, with statewide coordination transferring to Audubon Texas in summer 2022, per Defenders of Wildlife. Farther south, the San Diego Bird Alliance has cited BirdCast data showing nearly 20 million birds crossing San Diego County during a recent fall migration, and close to 67 million during a recent spring migration.
The broader context makes the ask feel less trivial. The 2022 State of the Birds report found that nearly one in four breeding birds had been lost from the United States and Canada over the preceding 50 years, according to the San Diego Bird Alliance. For Oregonians watching millions of birds move overhead this weekend, the Bird Alliance of Oregon's message is that protecting them doesn't require much — just a dark window and a few hours of patience until the flocks pass through.
