Currently, between 365 million and 988 million birds die in the US each year because of collisions with buildings and houses, according to a report released in January. As a result, a number of American cities and states — such as San Francisco and Minnesota — have adopted building standards that promote bird safety, such as special lighting conditions. Unfortunately, many architects are reluctant to make changes if it means obstructing a client's view by using things like semi-transparent window decals. So, as The New York Times reports, an increasing number of glass companies and research labs have started to think about ways to stop these deadly collisions, without hindering our view.
"Almost anybody you talk to has seen a bird hit a building or heard a bird hit," Christine Sheppard, a bird collisions campaign manager with the American Bird Conservancy, told NPR. Birds don't have very good depth perception, she said, so reflections in a glass window can make it seem like there isn't a window there at all.
"glass companies realize there's a market for bird-friendly products."
One idea that's being tested out by researchers at Fordham University is to see if adding thin white and black vertical stripes to windows can deter birds from crashing into them. When birds enter wind tunnels partially blocked by striped glass during experiments, they tend to avoid the stripes. Another idea — one that is both less obtrusive and much more expensive — comes from European Glass manufacturer Arnold Glas. The company has come up with a patterned, ultraviolet reflective coating that has the advantage of being almost transparent to the human eye, while still being detectable by incoming birds. "Suddenly glass companies realize there's a market for bird-friendly products," Sheppard told The New York Times.
But it's not just the windows themselves that are causing problems — it's also how they're used. Large mirror-like building facades, for instance, are especially hazardous to migrating birds. So Fordham University researchers are also trying to figure out just how much space they can put between the stripes on large pieces of glass. If they can find the "sweet spot" — one that will please architects and repel birds — the stripes will go a long way to curbing these accidental avian deaths.