BERKELEY (KPIX 5) — A new report from the National Audubon Society says climate change could have a devastating impact on birds–not just struggling endangered species, but the ones you see everyday.

We are surrounded by birds. In the Tilden Nature Area above Berkeley, they are everywhere; in the skies, the trees and rustling about in the underbrush. But lately observers have noticed something different on their bird watching hikes.

“We’re seeing, at times, only half those numbers of actual birds and maybe you’ve noticed it’s much quieter when you go on walks,” said Pam Young, Executive Director of the Golden Gate Audubon Society.

Another recent report shows the number of birds in North America have dropped from 9 billion to 6 billion since the 1970s. And now, a National Audubon study released on Thursday has a dire warning for the future.

“If the global warming rises 5 degrees, we’ll have a direct effect on many birds that may well go extinct,” said Young.

Climate activists combined bird count data with computer model projections and have concluded that a five degree rise in global climate would affect food supply and habitat enough to put two thirds of North American bird species at danger for extinction.

And according to local Audubon Society officials, that includes common birds like sparrows, ducks, woodpeckers and even the California Quail.

G.G. Audubon Society board member Laura Cremin said she has resigned herself to the idea that some common bird species will go extinct.

“Yeah, I know that you’ve been seeing them decrease so it’s by what amount and at what level we can stop it,” said Cremin.

The scientists behind the study are advocating a goal of zero carbon emissions within the next 30 years. In trying to move people to action, the study’s computer models paint a pretty extreme picture.

But they say it’s important to understand that the creatures that are most numerous are often the most fragile.

“They seem so abundant, they’re everywhere…but this isn’t something that’s guaranteed if we don’t take action,” said Cremin.

The National Audubon Society has an online visualizer tool that allows people to see the expected impact of climate change on their individual counties. The tool can be accessed here:  Birds and Climate Visualizer.