It’s not every day you hear a bobwhite in Brooklyn. In fact, you could easily live in New York City for 15 years, as I have, and never once hear the distinctive "bob-WHITE" whistle of this small, chicken-like bird. But there it was one afternoon last spring, right outside the studio where I had just picked up my three-year-old from tumbling class.

"Hey, listen," I told my daughter, "it’s a bobwhite." But then the sound stopped, replaced by the song of another bird, one I didn’t recognize. I looked in the direction of the music and caught sight of an electronic speaker and a placard attached to the side of the building. Both birdcalls, it turns out, were part of a project known as Birds of Brooklyn. Local multimedia artist Jenna Spevack came up with the idea after returning to the borough from a summer artist-in-residency program in rural Connecticut.

"For months, there was always just a cacophony of birds," Spevack told me when I contacted her about the unusual art project, "and I’d gotten so used to birdsong as background noise. Then I came home and noticed the absence."

Using information from the Cornell Lab of Ornithology, Spevack selected 20 different bird species that were once common here but are now declining or extinct, and she put together an audio loop of their songs and calls. Since launching the project in August 2010, she has obtained grants from organizations such as the Brooklyn Arts Council and the New York City Department of Cultural Affairs to install small metal boxes with speakers in nine sites across Brooklyn, all in discreet spots so that passersby will hear the songs without immediately realizing that they’re recordings.

Today, among the sounds of car alarms, reversing trucks, and planes descending into LaGuardia, you might catch the song of a piping plover, a screech owl, or some other bird that used to flourish here but no longer does. You might hear the cheerful "chick burr" of the scarlet tanager, for example, while tucking into a salami sandwich at the Canadian-Jewish deli on Hoyt Street. Or the clear, sweet whistle of the eastern meadowlark as you enter a Cobble Hill bakery.

Listen for the deep "who-doo-dooh" moan of the extinct heath hen as you approach the green building contractor on Bergen Street. As more of the birdsong gets woven back into the environment, the city sounds increasingly like it did in the past.

Brooklyn once was home to hundreds of birds that inhabited the area’s natural wetlands, oak and hickory forests, and farms. Some species, such as the heath hen and the Eskimo curlew, fell victim to over-hunting. Others relocated to the leafier outskirts as industrial development picked up in the 1800s. Birds like the bobwhite declined more recently -- not in Lenape Indian- or Model-T-Ford-era Brooklyn, but more like the Welcome Back Kotter era. Bobwhite numbers in the eastern United States have plummeted over the past 40 years, from 31 million to 5.5 million, according to the Audubon Society. The usual suspects -- sprawl, increased development, intensified agriculture -- all played their part, but the major reason for the decline was lack of habitat.

Growing up in southern Illinois, I used to hear bobwhites all the time, so the encounter near the tumbling studio really took me back. But such experiences don’t need to feel so anachronistic. With just a little encouragement, birds can thrive in urban environments. Since the New York City Audubon Society and the National Park Service finished restoring Floyd Bennett Field as a grassland bird habitat in 1990, for instance, many species have begun to return. And these days, groups like the Brooklyn Bird Club and Cornell’s Celebrate Urban Birds are overseeing several programs -- distributing seeds for bird-friendly flowers, enlisting volunteers to help count migratory and resident birds in places such as Prospect Park and the Brooklyn Botanic Garden -- to help make New York more hospitable for our feathered friends.

Hearing a recording of a bird that disappeared decades ago can be a pleasant surprise, of course, but growing accustomed to the real thing would be even better.