When birds collide
In “Collision course” (SN: 9/21/13, p. 20), Susan Milius told the stories of two ornithologists working to develop windows that birds won’t fly into.
With few exceptions, readers were sympathetic to the plight of birds that either don’t see windows or incorrectly interpret reflections. William Thompson e-mailed about his Colorado home: “At the height of bird activity, we see about five such collisions per month with a 20 percent mortality rate. These collisions usually occur when there are a large number of birds flying, and the level of aggression/agitation is heightened. We suspect a significant number of these collisions result from the bird essentially attacking [its own reflection].” His response to the problem was to consider the underlying cause: “We readily admit that as the owners of an overly large house we are complicit in the more