Save Migratory Birds by Reducing Collisions!
Each Spring and Fall, about five million birds (of 250 bird species) migrate through Chicago. These birds are often attracted to building lights and lighted glass areas, with fatal outcomes. While lights can distract birds from their migration paths, bird fatalities are more directly caused by the amount of energy they waste flying around and calling out in confusion. The exhaustion can leave them vulnerable to other urban threats.
Good light reduction practices significantly lower fatalities. Multi-story buildings can save many birds by turning off decorative lighting from 11 PM until daylight each day from March 15 to June 15 for spring migration, and again from August 15 to November 15 for fall migration. Tenants are also encouraged to turn off lights or draw blinds during these periods.
What You Can Do to Help
- Turn off exterior decorative lighting, including lights on antennas, logos, clocks, and other displays or illuminations.
- Turn off pot and floodlights.
- Substitute strobe lighting wherever possible.
- Reduce atrium and lobby lighting wherever possible.
- Turn off interior lighting wherever possible.
- Substitute task and area lighting for workers staying late or pull down window coverings.
- Down-shield exterior lighting to eliminate horizontal glare and any light directed upward.
- Install automatic motion sensors and controls wherever possible.
- When converting to new lighting, assess quality and quantity of light needed, avoiding over-lighting with newer, brighter technology.
- Encourage tenants to turn off lights and close drapes or blinds after 11 PM until daylight.
- Encourage scheduling of cleaning crews to finish before 11 PM, enabling lights to be turned off on multiple floors
Frequently Asked Questions
Why are multi-story buildings a danger to migrant birds?
It is believed that lights on multi-story buildings interfere with the navigation systems of birds unlucky enough to encounter them during migration. Confused, they circle the buildings repeatedly and die from exhaustion or collisions.
What kind of birds are involved?
Over 250 bird species migrate through Chicago, totaling about 5 million birds. Many of them are small migrants from the tropics, including warblers, thrushes, tanagers, hummingbirds, and others.
What are other ways buildings can reduce bird collisions?
Research indicates that most migratory bird collisions occur at elevations below the 12th floor. In addition to reducing or eliminating lighting during migratory seasons or installing fritted windows or film in strategic locations, building owners and managers are also encouraged to consider strategic placement of landscaping—both indoors and outdoors—to limit visual cues that attract birds and increase the risk of collisions.
Contact Information
If your building experiences bird strikes or has problem areas, contact Chicago Bird Collision Monitors for solutions and suggestions at 773-988-1867.
For more information, contact Chicago Audubon Society at 773-539-6793 or Chicago Bird Collision Monitors at 773-988-1867. Learn more about bird collisions and light reduction at www.birdmonitors.net or www.flap.org.