Californians from all walks of life will take to the outdoors this holiday season to participate in the 115th annual Audubon Christmas Bird Count, the longest-running wildlife census in the world. Between Dec. 14, 2014 and Jan. 5, 2015, thousands of Californians will transform into volunteer scientists to assess the size of bird populations in local communities throughout the state. The data from these counts will be compiled with others from around the nation and beyond, and will ultimately help Audubon track the progress of imperiled species and gauge the impact of environmental threats to birds and habitat.

“This is the time of year when bird enthusiasts gather together to do what they enjoy the most, all the while making a tremendous contribution to science,” said Brigid McCormack, executive director of Audubon California. “These dedicated volunteers have enabled us to learn fascinating things about the impact on birds from climate, drought, habitat loss, and development, among other things.”

Christmas Bird Counts will take place in virtually every county throughout California – in places both familiar and remote. This year, well over 100 counts are scheduled in the state, and more than 5,000 are expected to participate.

Audubon has used Christmas Bird Count data to predict how California birds will respond to climate change, and to identify which habitat areas will be critical to future conservation. Recently, Christmas Bird Count data laid the foundation for Audubon’s groundbreaking study into how global warming will alter the geographical ranges of North American bird species in a recent groundbreaking study. Researchers found 314 of 588 species are at risk of being climate threatened, they face losing more than 50 percent of their range by 2080.

Many decades of data not only helps identify birds in need of conservation action, it also reveals success stories. The CBC helped document the comeback of the Bald Eagle, Peregrine Falcon and significant increases in waterfowl populations, all promising results of conservation efforts.

The Christmas Bird Counts began more than a century ago when conservationists – as an alternative to holiday hunting contests – banded together to identify, count and record all the birds they saw. One of the first counts was held in California in 1900, in Pacific Grove.

The Audubon Christmas Bird Count is the longest-running citizen science wildlife survey in the world.

“The Audubon Christmas Bird Count harnesses volunteer power to gather knowledge that shapes conservation policy at enormous scales in this country. I couldn’t be prouder of the volunteers who contribute each year,” said Audubon President and CEO David Yarnold.

In each Christmas Bird Count, volunteers must count birds within an established 15-mile diameter circle. Sometimes these circles are in the open landscape, while other times they are on private lands or even residential neighborhoods. Each field party includes at least one experienced birdwatcher.