This story says it all: 13.7 million birds die every day in the U.S.

At the beginning of this month when about 5,000 red-winged blackbirds fell from the sky in one night in Arkansas, biologists were called on to put a damper on public speculation about pesticides and secret military tests by reminding everyone how many birds there are and how many die. They often do so as a result of human activity, but in far more mundane and dispiriting ways than conspiracy buffs might imagine.

“Five billion birds die in the U.S. every year,” said Melanie Driscoll, a biologist and director of bird conservation for the Gulf of Mexico and Mississippi Flyway for the National Audubon Society.

Read full story here: http://thinkprogress.org/climate/2011/01/19/207357/angry-birds-13-7-million-are-dying-every-day/