In case you missed it last week, the numbers have changed.
The Smithsonian Conservation Biology Institute and U.S. Fish and Wildlife Service developed a mathematical model, used data from 21 of the most rigorous cat-wildlife studies, and ran the numbers on cats.
The results were quite surprising. 2.4 billion birds are killed by cats every year in the U.S. That’s two to four times the old statistics.
Compare this new data to other human-induced causes of bird mortality(*) and cats are now on top.
- Cats: 2.4 billion
- Windows: 1.0 billion
- Power lines: 0.174 billion
- Communication towers: 0.051 billion
- Windmills: 0.0004 billion
So you can stop worrying about windmills.
If you want to save birds’ lives, keep your cat indoors. I do.
Read more about this study including information on feral and pet cats in the New York Times.
(*) p.s. I’m not sure where habitat loss fits in now, but it has always been the leading cause of human-induced bird mortality.