START A PETITION 27,000,000 members: the world's largest community for good

Windows Kill a Billion Birds a Year

Windows Kill a Billion Birds a Year

Cats’ reputations have taken a hit in recent years as research has revealed just how many birds die at their furry paws.

A 2012 study by the University of Georgia and National Geographic found that U.S. cats could kill as many as 4 billion birds and small animals a year. Similar research in New Zealand prompted a prominent economist to propose ridding the country of domestic cats. But teeth and claws aren’t the only threat to aviation populations.

Between 365 and 988 million birds die annually from crashing intowindows in the U.S., according to a new report. Other estimates put that number as high as 1 billion.Most bird collision deaths don’t occur on skyscrapers but with the windows of smaller structures. Buildings four to 11 stories high account for 56 percent of the deaths, according to an Oklahoma State University study. Residences account for 44 percent of bird collisions, and skyscrapers cause fewer than 1 percent. A small building kills only a few birds a year compared with the 24 that die due to a single skyscraper, but the United States has 15.1 million low-rise structures and 122.9 million small homes but only 21,000 skyscrapers.

Researchers also found that certain species of birds are more vulnerable to deadly window collisions. Anna’s hummingbirds, black-throated blue warblers, ruby-throated hummingbirds, Townsend’s solitaires and golden-winged warblers top the list.

How can we make glass less dangerous?

There are only a handful of groups actively testing ways to prevent birds from flying into glass. Ornithologist Christine Sheppard oversees one at the Powdermill Avian Research Center in Rector, Penn. Her research has shown that opaque stripes or dots covering just 5 percent of a glass surface can prevent 90 percent of collisions. However, the problem lies in getting people to use such glass. Ornithologist Daniel Klem Jr. has been working to create no-crash glass for nearly 40 years, and he’s had some success.

He found that birds but not people can see the short wavelengths that make up ultraviolet light. He theorized that window patterns that show up only in UV could deter birds while still giving people a clear view.A chemist devised a UV film that dramatically reduced bird collisions based on Klem’s research, but attempts to finance the project failed. Still, other companies and research labs are testing and marketing UV-reflecting glass and decals, and some places even require buildings to meet particular bird-safety standards. Minnesota structures that receive state funds must include certain bird-safety features in their plans, and since 2011, San Francisco buildings near parks or waterfronts must adhere to avian-safety requirements.

Article by Laura Moss


Read more: Health & Safety, Home, Nature, Nature & Wildlife

have you shared this story yet?

go ahead, give it a little love

Kara, selected from Mother Nature Network

Mother Nature Network's mission is to help you improve your world. From covering the latest news on health, science, sustainable business practices and the latest trends in eco-friendly technology, strives to give you the accurate, unbiased information you need to improve your world locally, globally, and personally all in a distinctive thoughtful, straightforward, and fun style.


+ add your own
10:01PM PDT on Mar 20, 2015

Another thing which increases this problem for birds is the trend for people to build without eaves, verandahs or overhangs of any kind. Not only is this more dangerous for birds, but it means your home gets hotter in summer. Personally, I prefer the look of windows with overhangs; it's much more interesting architecturally than a flat window in a flat wall, and saves on air-conditioning costs too.

5:53AM PST on Jan 9, 2015

thanks for sharing :)

4:35PM PST on Feb 22, 2014

wow- thank you for the information

3:43AM PST on Feb 19, 2014


9:49AM PST on Feb 18, 2014


6:07AM PST on Feb 18, 2014


10:45AM PST on Feb 17, 2014


2:23AM PST on Feb 17, 2014

I would be happy to buy inexpensive UV-reflecting decals to put on my windows to warn birds, and I'm on a very tight budget. Surely pet stores and wildlife-oriented stores, bookstores, etc could carry them and make a profit?

9:07PM PST on Feb 16, 2014


8:59PM PST on Feb 16, 2014


add your comment

Disclaimer: The views expressed above are solely those of the author and may not reflect those of
Care2, Inc., its employees or advertisers.

people are talking

I find myself to be the opposite. Being with someone gives me more of a reason to want to exercise …

Their reactions are priceless!

“When my Husband of eight years walked out of my life for the third time I had a bad feeling th…

Very sweet like most Cats videos. Thank You.

I, too, enjoy my alone time. I've been lonely in crowds so just having someone with you doesn't gua…


Select names from your address book   |   Help

We hate spam. We do not sell or share the email addresses you provide.

site feedback


Problem on this page? Briefly let us know what isn't working for you and we'll try to make it right!