In our work at the WCC, we often run into the perception that hitting a window is a minor thing for a bird to experience. We envision a quick cartoonish bonk and maybe a few minutes sitting stunned before flying off, no major harm done. I think sometimes we wildlife rehabilitators reinforce that notion by advising folks to wait and see if the birds who hit their windows “recover” before driving them to us. Although we’d prefer to see and examine any bird that hits a window, we continue to give this advice because some birds are truly only stunned, and it can be quite a stressful experience for the animal to travel to the center unnecessarily. However, the ability to fly off doesn’t mean that that the birds haven’t received life-threatening injuries that can still lead to fatality, which is why this is a practice that those of us in the wildlife hospital wrestle with, and frequently discuss changing.
It doesn’t help that injuries from window strikes can have extremely subtle initial symptoms, even if they are quite serious and life-threatening in the long term. It’s true that a large percentage of birds that have hit windows are unable to fly away because they have serious head trauma that damages their balance, coordination, or awareness. Many also have a fracture or dislocation of the coracoid or clavicle bones, essentially the “struts” in a bird’s chest that the muscles pull against to flap and fly. Others, though, may be able to fly away despite their injuries. Because birds hit windows head first, we tend to see jaw fractures and eye injuries that might not prevent a bird from flying away but can make it impossible to hunt or eat normally. There are also injuries that can take hours or even days to show up, like swelling and bruising, or even injuries to the bird’s respiratory system that result in air leaking into places it doesn’t belong. These injuries might not be visible and won’t necessarily interfere with the bird’s ability to move right away, but can become very severe later on.
Ultimately, taking the time to bring a bird that hits your window into the center for an evaluation by our trained medical professionals is the safest option and is, in my opinion, worth the peace of mind even if we do send the bird home right away. But I also hope that as a society we can take this threat to birds more seriously, especially since prevention is truly as simple as properly treating exposed glass so that it is visible to birds, reducing light pollution, and using bird-safe designs in our new buildings. We make this plea regularly each and every year, and this migration season is no exception: go out and make at least one more window or light in your life bird safe! For more resources and details, visit the Bird Safe Building page of our website.
