Window strikes kill hundreds of millions of birds annually, making glass buildings one of the leading human-caused causes of bird death. Simple interventions can dramatically reduce this avoidable harm.
The scale of suffering caused by window strikes is enormous but largely invisible — most strikes happen unwitnessed, and many injured birds die out of sight. Birds that do not die immediately suffer from concussion, internal bleeding, and disorientation before dying. The trauma of the strike itself is acutely painful. Because preventive measures are effective, affordable, and widely available, most window strike deaths and the suffering they cause are preventable. Building design standards that incorporate bird-safe glass or external visual markers could eliminate the vast majority of this harm.