A Year of Helping Birds: Make Migration Safe: Windows, Lights and Bird-Safe Design
As detailed in this series’ first post, bird populations in North America have suffered a terrible decline in the past generation; there’s almost 30% fewer birds now than there were since the 1970s. That’s about 3 billion birds in 50 years, according to the Cornell Lab of Ornithology. We’ve lost large amounts of many popular species, including several favorite backyard birds, such as Blue Jays (1 in 4 lost), red-winged blackbirds (1 in 3 lost), and dark-eyed juncos (1 in 3 lost). There are many reasons for this decline, and in this month’s post for the series A Year of Helping Birds, we’re focusing on the dangers of windows and lights.
Migration’s Fatal Danger
Migration is a dangerous time for birds. Every spring, billions of birds make the long journey from their wintering grounds in the south to their nesting habitats in the north. They’re traveling far for food and family, but tragically, many of them never make it due to collisions with buildings and other structures. Fall migration is almost equally deadly. In fact, up to one billion birds are killed in the United States each year due to these collisions, according to this study.
Because of their density, urban areas are noticeably dangerous, and Chicago has the most deadly skyline in the country, due to several factors:
Dead birds collected by the Chicago Bird Collision Monitors are used for research by the Field Museum's Bird Division. (Josh Engel, The Field Museum)
Location - Chicago is located on one of the country's busiest migratory paths - millions of birds have been traveling through the Chicago area for thousands of years.
Windows - Chicago has a high density of tall buildings with reflective windows and transparent glass that birds may try to fly through or towards.
Lights - Chicago has a high proliferation of lights which disorient birds, many of whom travel at night.
Volunteers for the Chicago Bird Collision Monitors see the devastation first hand on their early morning bird rescue patrols of downtown Chicago, where more than 7,000 dead and injured birds are found annually, just a percentage of the actual number of birds who die (others are scavenged by other animals such as rats and gulls, or simply swept into the garbage). Injured birds are brought to local wildlife rehabilitators.
Surprisingly though, residential and low-rise buildings actually kill more birds overall than skyscrapers, as detailed in this article from National Audubon. Many people don’t realize birds are hitting their windows because they’re not usually home to hear the deadly thump, and the dead birds are scavenged by cats or other animals. Residential bird collision reports increased during the pandemic when people were home.
One of the lucky ones: an injured yellow-bellied sapsucker recovers in the safety of a brown paper bag. (Photo: Annette Prince, Chicago Bird Collision Monitors)
Fortunately, there are multiple ways to reduce bird window collisions. You can make your own home safer, and you can help support bird-friendly efforts in your community.
Lights Out at Night
Did you know that billions of birds such as warblers, hummingbirds, and thrushes, migrate at night? You can actually hear them on heavy migration nights, which is a fun way to witness the magic of birds; but traveling at night is dangerous for birds because of lights. Birds become disoriented by lights, especially in metropolitan areas with lots of lights. They lose their way and crash into buildings. A simple solution: reduce lights - which can greatly reduce bird deaths by more than half. Dave Willard, ornithological collections manager emeritus at Chicago’s Field Museum (and former Chicago Audubon president) made this remarkable discovery a few years ago while researching bird deaths at McCormick Place in Chicago’s southern downtown. By turning off just half the lighted windows during spring and fall migration, his study revealed, fatal bird collisions could drop by 60 percent, according to this fascinating article.
Lights Out is a national program organized by National Audubon to convince building owners and managers to turn off excess lighting during the months migrating birds are flying overhead (March 15 to early June, and late August to mid-November). This includes turning off exterior decorative lighting, logos/signs, pot and flood-lights, strobe lighting and any other lighting visible to birds at night.
Lights Out Chicago is a local effort, a collaboration between the city of Chicago and Chicago Audubon Society. Many downtown businesses take part in this effort, turning off unnecessary lights during migration. It’s estimated that 10,000 birds are saved from death every year because of Lights Out Chicago. You can participate too - turn off your home and business lights during migration and help birds migrate safely. If you live in a building that is not participating, National Audubon’s Lights Out page is a great resource of information, including sample letters to governments or building managers.
Make Windows Safe At Home
Windows are like mirrors - they reflect the sky, trees and shrubs around them, and birds flying fast don’t see the glass at all. They see open air, and often fly directly into hard glass at top speed, causing injury or death. But there’s a few things you can do to reduce the risk of birds crashing into your windows by making them less reflective:
If you use a bird feeder or bird bath, place them within 3 feet of windows, so birds feeding or visiting your bird bath near your home don’t have time to build up speed when flying away.
Plant vegetation close to your windows to “break up” the reflection.
There’s a variety of products you can use on windows, such as paint, decals or screens (see list below). It’s important to make sure coverage is tightly spaced - less than 2 inches apart.
Don’t clean your windows until after migration - the dust on windows reduces their reflectiveness.
Close curtains or shades.
Turn off exterior lights at night during migration
What and Where to Make or Buy
Window safety products - The Chicago Bird Collision Monitors
Database of various products - American Bird Conservancy
Start Planning with Birds in Mind: Bird-Friendly Design
Bird-friendly design is an integrated and expansive approach to enlist governments, architects and businesses to ensure buildings are safe for birds: retrofitting old buildings and designing new buildings using materials and designs that minimize harm to birds. The American Bird Conservancy has a Bird-Friendly Building Design Guide (60 page PDF) that summarizes problems and solutions.
Bird-friendly Aqua Tower, Chicago, IL (Photo by Sonder Quest/Unsplash)
Government mandates - in the form of standards, laws and ordinances - are needed to ensure that guidelines are followed by architects, builders, and businesses, so that birds are protected. Sadly, birds can’t vote, so progress is slow and piecemeal, as the preventable tragedy of bird collisions is not well known or prioritized. Laws are in various stages of consideration in many cities across the US and Canada. In 2019, New York City passed a landmark Bird Friendly Materials bill requiring “bird-friendly” glass on all new construction and restorations, to reduce building collisions. San Francisco and Toronto have similar laws. In Chicago, a Bird-Friendly Design ordinance was approved in 2020, but is yet to be implemented.
In Illinois, Governor Pritzker signed the Bird Safe Buildings Act in 2021, requiring all new state buildings to incorporate bird-friendly design. Federal legislation has been more difficult to pass: the Federal Bird-Safe Buildings Act has been in limbo for several years.
Still, many architects choose to incorporate bird-friendly design (along with other environmental benefits), such as Chicago’s Aqua Tower and the Milwaukee Bucks’ Fiserve Forum.
Be a Voice for the Birds
Although much progress has been made in reducing bird deaths due to window collisions, lights and windows are still a significant danger to birds, and these preventable deaths contribute to overall bird population losses. You can help in many ways:
Raise awareness of the problem: Read through the resources below and share this article and resources with others.
Contact your elected officials to enact bird-friendly guidelines and ordinances.
Get involved with local development - when new buildings or renovations are proposed, communicate the need for bird-friendly design. The bird-friendly design of the Milwaukee Bucks’ stadium was initiated when a local birding group Bird City Wisconsin educated the Milwaukee Bucks’ president on migration and bird friendly design.
Contact local businesses where lights are on at night during migration; educate them on migration and the dangers of lights.
Update your windows to make them safe.
Turn off exterior lights during migration.
Volunteer with the Chicago Bird Collision Monitors or other local bird rescue group.
Learn More
What to Do if You Find An Injured Bird - In the Chicago area, contact Chicago Bird Collision monitors for help at: 773 988 1867.
Chicago Bird Collision Monitors - a volunteer conservation group dedicated to the protection of migratory birds through rescue, advocacy and outreach
Volunteers Collect Dead, Injured Birds in the Loop - WTTW News
As many as a billion birds are killed crashing into buildings each year — and Chicago’s skyline is the most dangerous area in the country - Chicago Tribune
Turning Off Lights at Night Could Halve Bird Deaths On Chicago’s Lakeshore - National Audubon Society
Lights Out - National Audubon Society
Lights Out Chicago - City of Chicago
Glass Collisions - Preventing Bird Window Strikes - American Bird Conservancy
Bird-Friendly Building Design Guide (60 page PDF) - American Bird Conservancy
Window safety products - The Chicago Bird Collision Monitors
Database of various products - American Bird Conservancy
October 5. 2023 Update: Almost 1,000 migrating birds die in Chicago after crashing into McCormick Place Lakeside Center, a 40-year record - Chicago Tribune
Check out all of our Year of Helping Birds articles
