how to help prevent window strikes by songbirds
IDIDN’T WASH MY WINDOWS ALL SPRING AND SUMMER, and though I hated looking out through dust and rain splatters and Jack’s many pawprints, it was part of an experiment to see what—if anything—might help reduce the horrible event of window strikes by songbirds, a leading cause of their death. Now it’s bird-feeding season, and with last night’s snow here and the added reflection it causes, this important topic came to mind again. Here’s what I know:
The U.S. Fish and Wildlife Service estimates that as many as billion birds die each year after striking plate glass. It happens at skyscrapers and private homes, in cities and rural settings. I used to think it was just me—as if I was doing something horribly wrong, but a few years ago I read an article by David Sibley (author of the Sibley Guide to Birds series) that revealed how troubled even he was at his own home with the same problem, and how he was working to solve it.
Sibley tried various tactics, including drawing a mesh-like grid with yellow marker on the insides of his windows, and stringing monofilament vertically on window exteriors and more. You can read more about his experiments, and recommendations, in this article from Birders World magazine (a pdf).
Cornell’s Lab of Ornithology recommends a taut, 5/8-inch mesh stretched 2-3 inches from the glass surface. Their other tips, and more about why birds strike windows, is in this article.
Everyone agrees that what won’t work is a single decal (traditionally a hawk was the image recommended, as if it would scare birds away) though UV-reflecting decals, if spaced closely for substantial exterior coverage as the packages explain, can help. I tried this—using the Window Alerts brand–but I thought it was worse than looking through a screen would be, frankly. You might disagree. The big advantage: All you have to do is stick them on the exterior glass, and you’re set—but remember, they have to be spaced close together. I see that there are now whole sheets of see-through, reflective fabric available—it looks like that stuff they put ads on city buses to me!
Next on my list to explore are Sibley’s other recommendations (whether homemade facsimilies, or mail-ordered):
- Acopian Bird Savers (very simple “curtains” made of nylon cord spaced 4 inches apart)
- Bird Screens (flexible, and birds bounce off on impact)
Proper feeder positioning can sometimes reduce incidents. Place feeders either closer than 2 feet from the building, or 30-plus feet away. (The same is true for birdbaths, apparently; houses, such as bluebird houses, should probably be even farther–some sources say 100 feet.)
And by the way: From my own very unscientific test, I can confirm that not washing your windows works, at least pretty well. (I finally couldn’t stand it any longer, though, truth be told).
Update: In August 2012, NPR.org did this two-part series on birds and windows and efforts to improve architecture with birds in mind.