One second, they’re talking about the science that inspired their new book ... concluded that since 1970, North America had lost 2.9 billion birds — a decline of 29% in 48 years.

WASHINGTON — At least 112 North American bird species have lost more than half their populations in the past 50 years, according to a new report published March 6. Among the birds showing the ...

The number of birds in North America has declined by 3 billion in the last 50 years. That decline has hit some species of the animal harder than others with birds living in Canadian and American ...

North American migratory birds are becoming smaller as the planet warms due to climate change, a new study finds. Researchers from the University of California, Los Angeles (UCLA) examined more ...