What kinds of birds collide with buildings?
Bird mortality from window strikes has been recorded in more than half the bird species in the United States. Many of our favorite birds are included on this list, including ruby-throated hummingbirds, song sparrows, hermit thrushes, many kinds of warblers, indigo buntings, black-capped chickadees and gray catbirds. Over 250 species migrate through Minnesota, many of them small songbirds that migrate at night. Some of these are threatened species whose populations already show steep declines. Ironically, common city birds such as rock pigeons and house sparrows are infrequent collision victims. This may be due to these species’ adaptations for living among buildings. Birds have been migrating for millennia — why don’t they learn to avoid buildings? Birds collide with windows in the daytime when they see the outdoors reflected in the glass and think they have a clear flight path. Most migrants fly at night, and the artificial lights in tall buildings confuse them and cause them either
