UNITED STATES (WSYR-TV) — A new Cornell study is painting a startling picture of the wild bird population across North America.

Researchers found there are nearly three billion fewer birds now than in 1970. Scientists projected population data using weather radar, 13 different bird surveys going back to 1970 and computer modeling.

Researchers say the thinning of flocks is happening right before our eyes, but it’s so slow, we don’t often notice.

“One year you might get 10 robins in your yard, the next you might get nine, but then a year later you might get 12 because your neighbor’s birds are coming over as well and they’re feeding on your bushes. So, it’s actually one of those things that’s hard to detect as an individual,” said Mike Parr of the American Bird Conservancy.

The results were published in Thursday’s edition of the journal “Science.”

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