Understanding why birds collide with windows, the scale of mortality this causes, and the proven solutions available to homeowners and building managers to prevent these deaths.
Window strikes cause both instantaneous death and a range of serious injuries — traumatic brain injury, internal hemorrhage, broken bones, and disorientation — that leave surviving birds vulnerable to predation or starvation. The scale of mortality — hundreds of millions annually — represents one of the largest sources of anthropogenic bird mortality, yet most building occupants are unaware of the problem. The welfare case for prevention is compelling: the solutions are proven, affordable, and require minimal effort compared to the mortality scale they prevent. Each household that makes windows bird-safe potentially prevents dozens of bird deaths annually, and commercial buildings can prevent hundreds or thousands.