12/21/2012 04:07 pm ET Updated Feb 20, 2013

The Christmas Bird Count in Central Park

In the early morning hours of last Sunday, Dec. 16, I joined 72 other volunteers, from first-graders to octogenarians, in New York's Central Park for Audubon's 113th Annual Christmas Bird Count. Despite the intermittent drizzle and gray skies, we fanned out and spent the next four hours covering more or less every inch of the Park in an effort to count each individual bird in those 843 acres.

The pre-dawn wake-up didn't bother me, I'm used to getting up early because that's when the birds are most active and it's the best time to see them. And count them. After canvassing the Park and taking meticulous notes, we gather together inside at the Arsenal, the old military building near the Central Park Zoo, for soup and sandwiches, and the great tally begins. As each species name is announced, the findings are called out, sometimes to oo's and ah's from the crowd, as with this year's total of 18 Red-bellied Woodpeckers spotted around the Great Lawn.

It's a tradition in a lot of birding circles to come out for the Christmas Bird Count, a way to give something back to the birds for all the joy they've given us the rest of the year. Even after a decade of birding in Central Park, I'm still thrilled to realize such a vibrant piece of nature exists right in the middle of this giant city. The Park is full of runners and bicyclists and dog-walkers, but on this chilly winter day, it was also filled with 5,721 birds representing almost 60 species.

Prior to the 20th century, going out to find birds usually meant shooting them, even for nature lovers and bird-enthusiasts, including John J. Audubon himself. In 1900, the nascent National Audubon Society started the Christmas Bird Count hoping to change that practice. A hundred years before anyone had even heard of crowd-sourcing, amateur naturalists around the continent began banding together to collect an annual snapshot of bird populations. Today, the more than 2,000 separate Christmas Bird Counts that happen each year in North America and Latin America, the Caribbean and the Pacific Islands form the largest citizen-science survey anywhere in the world.

Of course, it's not possible to accurately count every last individual bird, but by using the same methodology year after year, trends and patterns certainly emerge. We have learned, for instance, that concerted efforts to protect wildlife can be very successful -- the populations of both the Bald Eagle and the Peregrine Falcon were in serious trouble before bans on certain toxics went into effect, something that Christmas Bird Counts helped document. Now, both species are doing well. Many others, however, are not. Formerly common species are becoming scare, and with the continual threat of habitat loss and the uncertainties of climate change looming, monitoring the health of the bird populations is a way of monitoring the health of the planet. So, every year I'll continue to do my part. I'll lose a little sleep around Christmastime to go out and count birds... again.

Jeffrey Kimball produced and the directed Birders: The Central Park Effect, a film about people and their need to connect with nature. The film, which premiered on HBO last summer and will be available on DVD in January, features a scene of the Central Park Christmas Bird Count. He was previously interviewed by the Huffington Post.