Protecting Bird Migration From Building Collisions: The Case for Lights Out in Urban Skylines

Bird collisions with buildings, known as "bird strikes," occur due to reflections, light pollution, transparent surfaces, habitat loss in urban areas, attractants like lights inside buildings, and certain architectural designs such as large mirror exteriors. These collisions are most common during bird migration seasons, posing a threat to bird populations. Efforts like Lights Out programs aim to reduce these risks and protect birds by encouraging building owners to turn off decorative lights during migration periods.Recently, a news reported that almost 1,000 migrating birds met a tragic end as they collided with the glass-covered McCormick Place Lakeside Center, a convention center in downtown Chicago in A SINGLE NIGHT!! (Refer to the attached photo: The Chicago Field Museum inspects the bodies of migrating birds that were killed when they flew into the windows of the McCormick Place Lakeside Center.)The bird collisions are common.

 

At the height of the fall bird migration season in North America, approximately 4 billion birds will traverse urban environments on their journey south to winter habitats. Unfortunately, millions of these birds will never reach their intended destinations, falling victim to fatal collisions with buildings. These collisions pose an additional threat to bird populations already stressed by habitat loss, predation, and other factors.The good news is that studies suggest dimming and turning off lights at night significantly reduces bird collisions. "Lights Out" campaigns have proven successful in various cities worldwide, and individuals can contribute by following bird migration forecasts, supporting local policies, and backing birding groups working on large-scale solutions. Recent legal initiatives, like the Migratory Local Wildlife Protection Act, mandate bird-friendly glass for new buildings and renovations. To prevent bird collisions, high-rise buildings can adopt Lights Out practices, which involve turning off decorative lighting on upper floors after 11 p.m. and keeping them off until dawn. This strategy is especially crucial during bird migration seasons, from March 15 to June 15 for spring migration and from August 15 to November 15 for fall migration. Residents of upper floors are encouraged to participate, and the guidelines apply to buildings with 40 or more stories and isolated buildings with 20 or more stories.Additionally, shorter buildings with extensive glass exteriors can aid bird safety by extinguishing exterior and interior lighting or drawing blinds during the same migration periods. For buildings featuring illuminated atria, reducing atrium lighting in the early morning hours can also help. Research recommends turning off lights (or drawing blinds) in all perimeter office and residential spaces on all floors from 4 a.m. until full daylight during Lights Out migration periods to minimize bird-window collisions as birds descend after their migratory journey.

 

Sources:https://www.npr.org/.../nearly-1-000-migrating-birds-died...https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0224164https://birdmapper-flap.hub.arcgis.com/pages/gbcm-guidehttps://www.smithsonianmag.com/.../turning-off-your.../....