A Christmas Bird Count in the Rio Grande Valley of southern Texas. Verónica G. Cárdenas

Christmas Bird Count

The Key to the Christmas Bird Count's 120 Years of Success? The People.

Drones and trail cams may be increasingly common in avian monitoring, but Audubon's CBC remains dependent on dedicated humans.

For close to five decades, Hugh and Urling Kingery have started nearly every first Saturday of Audubon’s Christmas Bird Count (CBC) in Denver’s Chatfield State Park, dressed warmly, clutching their binoculars, and eager to embark on a special day of birding. 

This Saturday, the couple will once again head to the park’s Heronry Overlook on the south side of the Chatfield Reservoir, where they will reunite with other dedicated participants, and perhaps also meet some new birders, on the 66th Denver CBC.

The nation’s longest-running community science bird project, the CBC has not only provided valuable data for hundreds of peer-reviewed studies, but it has also become an annual holiday tradition for tens of thousands of birders like the Kingerys.

“The Denver count always gets to 100 species or more, so there’s a lot of anticipation among the groups,” says Urling, who has been involved in the CBC ever since she met Hugh 45 years ago. “There’s always the adventure of not knowing what you’re going to find, and always hoping that you’re going to find something rare and wonderful. But it’s also an occasion to see the same people that we see only on this count and catch up, and we always have a good time.”

As the 120th CBC begins, the human effort behind the massive data collection project is stronger than ever. Last year’s edition continued a recent trend of record-breaking participation with more than 2,600 counts and close to 80,000 volunteers. (The number of birds tallied, however, was notable on a different front, hitting the second-lowest count in the past 33 seasons.) 

The growing involvement is great news for the CBC, since human effort has been key to the program’s success. But as technology like trail cameras and drones has become increasingly popular for avian monitoring and research, some participants are beginning to wonder, will the human aspect of the CBC eventually be replaced by these devices? This year marked the first time Kathy Dale, Audubon’s science technology director, received questions from participants and compilers on whether they can use remote sensing devices to survey birds for the CBC. “The answer is no, but there’s a reason why,” Dale says. “If these technologies were allowed, it would be a completely different kind of program. It wouldn’t be the CBC, fundamentally.”

This is because one of the defining aspects of the project is that it collects data not only on birds seen, but also on the human effort it took to see them. By including the time and distance each person covers, the data can account for the fact that more people surveying more areas will likely result in more birds tallied, even when there aren’t necessarily more birds in the area. 

This effort-weighted data is essential to maintain consistency year after year, and to make the numbers reliable for deciphering trends in bird populations. Dale says researchers routinely request the CBC data to understand how bird populations have been changing or moving, or as a well-regarded source to corroborate their own findings. The data have also contributed to Audubon science on how climate change will affect birds. 

Aside from consistency, technology—at least today—is simply not as qualified as humans to provide the expected level of thoroughness in an area survey like the CBC. Trail cameras can only monitor one spot, and only if movements happen to trigger them. Drones aren’t able to access all the crevices of the forest, trees, and branches without very likely disturbing the birds. And remote audio recorders fail to account for species that don’t sing, chirp, or screech. 

“I don't see a way to use any one particular technology right now to walk through the forest and see all the woodpeckers, kinglets, and other forest-dwelling birds that I see when I’m doing my Christmas Bird Count,” Dale says. “Trail cams can't do it all, not all birds vocalize, and drones can’t do it all. So I don’t know how you could try to conduct a real area count. You’d be leaving out a lot of birds.”

CBC director Geoff LeBaron says an equally important reason that humans are so irreplaceable in these counts is simply that people love doing it. “It’s part of their tradition,” he says. “People expend tremendous amounts of time and energy to do their Christmas Bird Count, and if it weren’t for the passion that they have for it, it wouldn’t be as successful or as well done as it is.” 

Doug Wilson (let) and Christmas Bird Count Director Geoff LeBaron on a Christmas Bird Count in Rhode Island. Annabelle Hendersøn

For LeBaron, it’s not just a time to go out birding, but also a chance to reconnect with a community he only gets to see when he returns to Rhode Island for the CBC. “I try to do it in Rhode Island because it’s the same count circle that I started in graduate school,” he says. “These places are where we develop a sense of community and a sense of place while loving the birds.”

In the case of the Kingerys, they decided to expand their CBC community in 1989 by starting a new count circle, the Denver Urban count, that takes place on January 1. Since then, every New Year’s Day, Hugh and Urling gather their fellow birders and welcome new participants to survey areas including Platte River, Buckley Field, and the magnificent Rocky Mountain Arsenal National Wildlife Refuge, where they never cease to be amazed by dozens of Bald Eagles, Ferruginous Hawks, and in some years, Long-eared Owls.

After a full day of censusing and bonding, the Denver Urban count’s 16 groups reconvene at the Washington Park United Church of Christ for their traditional potluck, during which they enjoy chili, finger food, and Urling’s signature brownies.

The Kingerys are a perfect representation of the dedication people have been putting into this community science project for more than a century. Although many have no scientific background, tens of thousands of individuals step out their doors on their designated calendar day—or days, as many participants join multiple counts—and spend some of the year's coldest mornings outside, doing their part. 

“I don’t have a scientific reason for doing the Christmas Bird Count,” Hugh says. He doesn’t have the stamina of his younger days and will not walk the entire route this year, but he’s still determined to participate in both the Denver and Denver Urban counts. “Essentially it’s a social thing with the birdwatchers, and it’s a holiday thing that has gone on for many years. But another reason I’ve done it every year for so long is because, well, I did it last year, so I have to do it this year. I suppose responsibility is the right word.”

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