Ornithologists Estimate That Highly Reflective Windows Kill 1-5% Of Migrating Birds

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We've all laughed at the classic cartoon gag where a bird flies headfirst into a window. Turns out this phenomenon isn't just a joke, it's deadly among migratory birds in Philadelphia, killing an estimated 1-5% of the migrating population.

Muhlenberg College ornithologist Daniel Klem Jr. has been investigating the bird-window problem for decades, and he has found that highly reflective windows account for between 100 million and a billion bird deaths a year. That means that windows kill more birds in a year than windmills, cats, and cell phone towers. Combined.


This shocking data led Audubon Pennsylvania's outreach coordinator Keith Russell to do some of his own research at Temple University. His results were just as grim, but there is hope: Russel found the most deadly buildings on Temple's campus, and the university is taking steps to save some bird lives.

Apparently, all it takes to save these feathered friends is to use "fritted" glass, or glass with evenly spaced frosted areas. The frosted bits give birds visual cues that alert them they are flying into a hard surface, not through empty air. Companies are also experimenting with treated UV glass that only the birds will see as being any different.


I never realized that birds hitting windows was such a huge danger in the bird community. Here's a whole flickr set of images of the smudges left behind by some serious bird crashes. All of a sudden I feel like demanding a solution to a problem I didn't even realize existed this morning. io9'ers Against Bird Collisions!

Glass-walled buildings can mean death for birds, killing 1 to 5 percent of them a year [via Physorg]


(CC image by finna dat on flickr)