Christmas Bird Count starts Saturday.
In various parts of Ohio, volunteer groups will span out over a 15-mile radius in designated areas and count every bird they see or hear.
Jeffrey White has compiled the official Buckeye Lake Christmas Bird Count for more than two decades. He says volunteers find it a rewarding experience, especially once they realize there's a lot more out there than the cardinals, sparrows or other common birds they typically see.
"There lots to be seen and you don't have to go very far to discover those things," he points out. "By the end of the day, you've seen maybe 50 or 60 different species of birds. But if you're sitting in your house watching TV, you miss out on all of that."
In 2018, more than 2,200 bird watchers in Ohio tallied 160 species. The Audubon Society's national annual bird count starts this weekend and continues through Jan. 5.
The counts are used to study the long-term health and status of bird populations across North America, helping to inform strategies to protect birds and their habitats.
White says species come and go over the decades, which can happen with changes in land use.
"Back in the 1920s, more areas were in agriculture," he points out. "Some of those places that used to be farm fields are now housing developments. So, there might be as many birds, but the species are all different depending on the habitat."
A recent study found that more than 3 billion birds have been lost in North America in the past 50 years.
Another study found North American migratory birds have been getting smaller, and their wingspans wider, over the past four decades - changes attributed to a warming climate.
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