SINCE 1900, the National Audubon Society has invited the public to participate in its Christmas Bird Count. Group leaders take participants on a trip to record each bird in the area. That data can be used for anything from narrowing conservation efforts to predicting flight patterns.

The Ogeechee Audubon Society, which oversees our area, has participated in the count sporadically over the years, but Larry Carlile is dedicated to making the count happen more regularly.

Carlile has been a wildlife biologist for the Department of Defense for the past 24 years and now serves as the compiler for the Christmas Bird Count, taking place in the Savannah and Harris Neck areas on Jan. 5. We spoke to Carlile last week.

How did the Christmas Bird Count get started?

Carlile: This is the oldest sort of citizen science project in the Americas. It began in 1900 in New York City by a fellow named Frank Chapman, sort of a pioneer ornithologist.

All those guys studying birds in the 1800s, when they went birding, they took a shotgun. They’d shoot the bird and then identify it. Around the 1900s, people became concerned about bird populations—that was when herons and egrets were being sacrificed for ladies’ hats. That was the height of fashion.

The first Christmas Bird Count wasn’t done In Savannah until 1913, and it went sporadically between 1913 and 2000.

How is the bird count done now?

Carlile: There's a new application that almost all birders use called eBird. That was developed by the Cornell Lab of Ornithology. You carry it around on your phone, go to a patch, bird the patch, and track your miles. You put in the species and number of each species you see. That's the main thing we're collecting on these Christmas bird counts. All the birds you see or hear by species, down to the individual. We do our best to get a good estimate.

This is a time-constrained count—it can only occur between Dec. 14 and Jan. 5. The Savannah count is always on the last Saturday, and this year it’s on the last day we can possibly count.

All that stuff then gets sent to me in the eBird format. We have 25 or 26 sections, and each team captain sends it to me. I compile it into a gigantic spreadsheet and estimate total hours, how many hours were spent owling, nocturnal birding—we do have owls in this area, and I’m a fanatic.

How do you make sure you’re not counting the same bird twice?

Carlile: For most species, it's not really a concern because most of the smaller birds are still fairly territorial, even though it's winter. They know where the food is and hang close by. That's why we have different areas and everyone confined to a particular area. If they go back over the same route, we make sure they know not to double-count.

Other birds, like eagles, are far-ranging and we ask people to collect a little more data on a bird like that. They note the time of day, the age of the birds—if it’s mature or immature—and the direction it was flying.

Then I compare that across all the eagle sightings and sometimes they pop out. If it was seen by this group at noon and by another group at 12:05, it’s the same bird.

Do you need to know about birds to participate in the Christmas bird count?

Carlile: No qualifications are required to participate. We assign people to a team leader, and the team leader is going to know the birds that occur here in the winter. Most birders get a huge thrill out of teaching somebody new how to recognize birds by sight and by all the different songs and all that .Once you get into it, probably 65 percent of going birding is listening. You'll hear those squawks and squeaks and chirps and tweets—that's the way you learn it. You see the bird while it's making a noise, and it's easier to make that connection. I've always loved that part.

Why is the Christmas Bird Count so important?

Carlile: The biggest benefit is for ornithological researchers. They're able to go back and access this very long data set. Anybody who's interested can see it, it's not a secret. People collect the data and crunch the numbers and run statistical models and help us direct where our bird conservation efforts would have the most benefit. We've noticed some populations of wintering birds are declining over time, so we apply some statistics to that and see if it's significant or not. We may be able to draw something out of that to say, "I think if we left some more pine snags in the woods after a logging operation, we wouldn't be seeing this decline in the redheaded woodpecker." Tons of papers published in peer reviews are using Christmas Bird Counts.

The other thing, which is more fun, is it helps us track eruption years of certain finches and nut hatches that depend on seed production in the boreal forest in Canada. Most years, seed production is great, but sometimes, depending on the weather, there’s nothing to eat. This year, we’ve had loads of red-breasted nut hatches show up in Georgia and along the coast. Normally, they’re not here at all, but there’s a food shortage in the boreal forest. Folks did predict that.

I bet you could look at the bird counts as an indication of environmental patterns, especially in regards to global warming.

Carlile: A lot of researchers are doing just that. As a matter of fact, one particular group of birds you might get some of that info is the duck. Ducks don't migrate like other birds. They pick up when it's time to migrate and then stop, moving south as they need to. As ponds freeze over, as conditions get rough, they go south. Historically, there was more diversity of ducks in the Savannah area than there are today. It seems fairly logical that those two things taken together are highly related—birds are a great indicator species for what's going on.

There's also a Great Backyard Bird Count later in February. Do those counts work together?

Carlile: The Great Backyard Bird Count was sort of another way to gather information about birds in the late winter, and not just the early winter. The Great Backyard Bird Count gives us an idea of what's hanging around, what birds may be moving back north again. We see some of the early migrants, like the purple martins.