The Great Lakes lie at the intersection of two migratory flyways, or superhighways, which brings over 350 bird species through the region each spring. While a beautiful spectacle, migration is a harrowing journey for birds who are in danger of colliding with glass.
Migrating songbirds like the Indigo Buntings and Swainson’s Thrushes are at highest risk of building collisions. These species also face steep population declines, and doing what we can to prevent window collisions will help ensure their survival.
Collisions with human-made structures is a leading cause of bird deaths in the United States, causing up to 1 billion bird deaths each year in North America. Birds cannot detect glass and healthy adults and juveniles are just as likely to collide with glass as unhealthy individuals are. When birds hit windows it is a life-threatening occurrence. Even birds that are able to fly away from the window are likely to succumb to their injuries later.
The good news is that there are opportunities to make your home or office more bird-friendly:
- Identify your problematic windows. To determine which windows have caused collisions, check them from outside 2 or 3 times per week, looking for imprints, smudges, or feathers on the glass, injured or dead birds, or clumps of feathers within 6-8 feet of the glass.
- Install bird-friendly solutions to your most problematic windows. Patterns on the outside surface of the glass are the best way to reduce bird-window collisions. Studies have shown that exterior window patterns need to be at least 2 x 4 inches apart, and that 2 x 2 inches is even better for smaller species, like Michigan’s Ruby-throated Hummingbirds, which are more prone to window-collisions.
For a list of quick and affordable ways to protect birds from your windows, check out American Bird Conservancy’s (ABC) Bird-friendly Windows Flyer and bird-friendly products database, Animal Help Now’s flyer on preventing bird window strikes, and Audubon’s resources on Reducing Collisions with Glass. Learn about Audubon’s Lights Out Program and how you can make your hometown safer for migratory birds.
For information on how you can get involved in Safe Passage Great Lakes building monitoring efforts, and what to do if you find a window-collision survivor, visit Audubon Great Lakes’ website.
- Heidi Trudell is a coordinator for Washtenaw Safe Passage, and serves on the boards of Detroit Audubon, and the Bird Center of Michigan. She has been a window collision researcher, bird safe building consultant, and advocate since 2003. She also serves as a Conservation Committee member for Black Swamp Bird Observatory.
ABOUT MI BIRDS
MI Birds is a public outreach and engagement program created by Audubon Great Lakes and Michigan Department of Natural Resources, which aims to increase all Michiganders' engagement in the understanding, care, and stewardship of public lands that are important for birds and local communities.