Save Our Sounds

In some libraries, noise is good

“I’m a bad person to go to a movie with,” says Greg Budney, curator of the Macaulay Library of Natural Sounds at Cornell University. He sometimes reacts to details that other people miss. He now rustles around his desk for a list he keeps of moments in movies that have disturbed him. “In Black Hawk Down, that scene where Delta Force is leaving Mogadishu and a soldier tries to call his wife,” Budney says, “you hear a chiffchaff in the background!” In real life, the little birds called chiffchaffs live in Europe.

EARLY PORTABLES. In 1935, Cornell University ornithologist Peter Paul Kellogg had to use a wagon to haul his amplifier and film recorder into the woods to record ivory-billed woodpeckers, a bird now presumed extinct. Div. of Rare and Manuscript Collections/Cornell Univ.
SONG DIALECTS. White-crowned sparrows along the West Coast (above) sing in different dialects, depending on where they live. The major differences between dialects come at the trill at the end, as reflected in two song spectrograms (below). Nelson

Nelson

SAYS WHO? The Macaulay sound library started with bird recordings, and the Borror library with insect sounds. Today’s archives have grown to include sounds of all kinds of creatures.

“There were Pacific tree frogs in The Hunt for Red October–in a Maine estuary,” he says. “It was horrible.”

Not that he can’t take a joke. Early in Raiders of the Lost Ark, the long, raucous call of an Australian kookaburra rings out in the Americas, but Budney appreciates it as homage to the corny roots of jungle-adventure movies. “It’s one of my favorite sounds in the whole movie,” he says. “Early Tarzan movies all had a kookaburra.”

Not everyone hears the sounds of nature with the mixed blessing of Budney’s highly tuned ears. Yet he contends that the sounds of birds, frogs, crickets, or whatever creatures are out there make a powerful part of the experience of nature for most people, regardless of whether they’re knowledgeable about chiffchaffs’ whereabouts. “Well-recorded sound has a remarkable ability to transport people,” he says.

The library where Budney works is now the largest in the world devoted to preserving and archiving nature’s sounds, with 150,000 recordings of 6,700 species and counting. In the United States, Ohio State University and the Florida Museum of Natural History also have substantial collections, and a worldwide tally includes about 14 sound libraries. Even patrons of the British Library in London can take a break from poring over Shakespearean first folios to hear a crested gibbon recorded in Vietnam, a screaming piha from Peru, or some 130,000 other sounds.

The recordings come from some of the great names in field biology, as well as from people taking a break from other professions. The fruits of these efforts draw scientists, conservation activists, merchandisers, and moviemakers. Sound librarians have even dug up recordings to be transmogrified into unnatural sounds, such as special effects in science fiction movies.

Early birds

Now libraries record creatures ranging from insects to reptiles, but what inspired many of the pioneers in nature recording were bird songs. In the British Library, the earliest surviving recording of a natural song, made by sound-collecting enthusiast Ludwig Koch, still preserves on a wax cylinder the sound of a thrush singing in 1889.

The possibility that modern technology might capture the songs of birds came to intrigue the first ornithology professor in the United States, Arthur Allen. He joined the Cornell faculty in 1915, and during the 1920s, he and his students were experimenting with catching bird songs on film used for the sound in the new motion pictures. It remained the medium of choice for recording animal sounds until the mid 1930s, even though the equipment was portable only in the sense that it could fit in a truck.

The mid-1930s brought a new technology: equipment that could be lugged into the field to cut grooves into 12-inch, 78-rpm disks. Allen’s team embraced the change, as did Koch, despite various drawbacks. Koch’s memoirs recount the complications on one of his recording jaunts when he gave a lift to a soldier, who lit up a cigarette. An ash ignited the flammable disc parings that had collected in the car seat.

Magnetic tape, developed in Germany during World War II, opened the era of reel-to-reel recordings, and all but the youngest libraries still have shelves of them. Today, sound collectors are moving to digital equipment, says Budney. In the corner of the 800-square-foot climate-controlled chamber that houses his library’s magnetic tapes now stand two of what he calls DVD jukeboxes.

Collecting sounds “requires a great deal of patience, but there are great rewards,” says Linda Macaulay of Greenwich, Conn. She has the same name as the library–she and her husband, William, contributed funds for its facilities–and she’s recorded more than 2,500 species for the collection.

Some of her rarest recordings come from birds that she knew where to find, but traveling to them was a challenge. For example, she trekked to northeast Gabon to record the gray-necked rockfowl, which builds big mud nests in caves there. The bald-headed birds, a little bigger than doves, emerged to hop around in the sunlight, making “very small” noises, she says. Her 1995 recording was the first that Cornell had received of the species, and since Ebola broke out in that part of Gabon 2 years after she visited, she’s not expecting a lot of people to rush in to make more recordings.

Reaching an animal isn’t the only problem, says Richard Ranft, curator of the British Library’s National Sound Archive Wildlife Section. The creature has to cooperate and make some noise.

A bat expert once asked Ranft to record the sonar of Spix’s disk-winged bat, which no one had done before. During the day, when the scientists could work easily, the bats used fleshy, disk-shaped suction cups on their wings to cling quietly to the insides of furled banana leaves.

Trying to work with free-flying bats at night wasn’t practical because they are so small. “You can fit a pair of them in a matchbox,” says Ranft. He finally succeeded by carrying a tent to the margins of banana plantations and creating a makeshift flight tunnel. During daylight, he woke a bat and eased it into the darkened tent, where it had to use sonar to navigate.

Unfortunately, the problem then became too much noise. Ranft was startled to discover that he had pitched his tent in an ultrasonically noisy spot, where a bush cricket blasted away at high frequencies. Eventually, he succeeded at recording bat sounds between the cricket’s outbursts.

Despite the many tales illustrating the value of good strategies, Macaulay admits that sometimes “you just get lucky.” She was recording sounds on Mt. Kinabalu in Borneo when a companion noticed a vocalization that none of the party recognized.

Macaulay recorded it and played it back, hoping that the mystery bird would come investigate. Eventually a bird did arrive, behaving to Macaulay’s eyes like an animal checking out its own call.

Macaulay was thrilled. Here was a Whitehead’s trogon. Ornithologists had described the species’ appearance but hadn’t identified its vocalizations. The bird didn’t call during its investigation, though, putting Macaulay in the maddening position of suspecting she’d just made the first recording of a Whitehead’s trogon but not being able to prove it. She and her colleagues spent the next 4 hours tramping around the mountain slopes trying to catch sight of a trogon actually calling. Fortunately, they succeeded.

Making nature recordings has challenges that have nothing to do with birds, Macaulay says. On a trip to Haiti and the Dominican Republic during one of the periods of high tension between the two countries, she had to work her way through six highway checkpoints each day to reach her field site near the border. Birding has its own diplomatic powers. “Whenever there are police or roadblocks, you just get out the bird books and start pointing to pictures,” says Macaulay.

After a week of negotiating in Haiti and the Dominican Republic without mishap, she was startled to see a heavily armed man step into the road and block her way. “It turned out he had heard about us and wanted us come to his house and identify a bird,” Macaulay says. So, she accompanied the head of the army for the border region to his home, where she found a burrowing owl in his garden.

Recording isn’t all about exotics on the edge of the world though. One of Macaulay’s one-of-a-kind treasures for Cornell came from a young great horned owl making an atypical sound she describes as “chattering hoots” literally in Macaulay’s back yard. And just last year, Budney realized that the Cornell library could use better recordings of pigeons, in part because they hang out in noisy locations.

Also, once is never enough. Any given species makes multiple sounds–calls for alarm, begging, staying in contact, mating, claiming territory, and so on. A good library needs both male and female versions of all those sounds, plus the squawks of developing youngsters. And then there’s geographic distribution. According to Budney, even 150,000 recordings aren’t enough.

Check it out

Scientists use sound libraries for all kinds of projects. Ornithologist Douglas Nelson, the director of the recordings collections at the Borror Laboratory of Bioacoustics at Ohio State University in Columbus, relies on recorded sounds for his studies of dialects in white-crowned sparrows.

Yes, he means dialects in much the same way the word applies to regional particularities in the way people talk. Nelson and his colleague Jill Soha are building on some 30 years of analysis of dialects in the Puget Sound subspecies of white-crowned sparrows. The late Luis Baptista began the project (SN: 4/15/00, p. 252: http://www.sciencenews.org/20000415/bob2.asp). Nelson and Soha can now identify about 10 different dialects along the Pacific coast from British Columbia deep into California. The dialects differ mostly in the way birds perform the final trill of their song. Some versions show up only in a small pocket of land, such as within 30 kilometers of Port Angeles, Wash., but others can spread over hundreds of kilometers of coast.

“Once you get the hang of it, you can tell where you are by listening to the white-crowned sparrows,” says Nelson.

For birds that are born with their songs–as opposed to learning them from a parent–recordings offer researchers a way to look for genetic differences that might distinguish species. Ned K. Johnson of University of California, Berkeley, for example, has analyzed recordings of western flycatchers. He found two consistent song types that, with other evidence, indicate that the bird should be considered two different species.

Tape recorders became the conservation biologists’ best friend during a 1990s push to catalog birds and other animals in tropical forests about to be cleared. The late superstar of bird recordings, ornithologist and conservation guide Theodore A. Parker III, reported that in a week of recording, he’d detected 243 species in a 2-square-kilometer area. Simultaneously, seven other ornithologists who relied on catching birds in a fine net required 54 days to document 287 species.

Ranft describes a more specialized form of census. In the early 1990s, conservationists feared that far fewer than a hundred Eurasian bitterns survived in the wild in Britain. But survey teams were having great trouble getting a good count of the birds, which usually slip silently among reeds in wetlands. By recording and analyzing males’ booming courtship calls, however, the surveyors were able to identify voices of particular males. Surveyors realized that earlier work had counted some males twice, not realizing that a male will travel several kilometers to try his luck again. New estimates set the number of males at around nine.

Despite Budney’s wincing moments in certain movies, he’s worked quite happily with several sound specialists in the entertainment industry, often on projects that have little to do with understanding wildlife. Sound designer Alan Splet called him during the production of Dead Poets Society and asked what the library could provide that would evoke fall at a New England private school. Budney supplied the calls of black-capped chickadees assembling in their winter flocks, raucous brays from blue jays, and the honks of migrating Canada geese.

On several occasions, Budney has supplied nature recordings to Gary Rydstrom of Skywalker Sound in Nicasia, Calif., who teased the originals into such novel forms that even Budney couldn’t pick them out. In Artificial Intelligence, Rydstrom manipulated woodpecker recordings to make the motor sounds of a robotic teddy bear.

In the futuristic cop thriller Minority Report, he added to the unsettling atmosphere of police workstations with bits of recordings of midshipman fish.

There’s a long tradition of juicing up inanimate sounds by mixing in a few animal calls, he says. “You put a lion roar into a crashing wave,” Rydstrom says, and make an explosion sound more interesting by adding a cougar growl. In the movie Backdraft, which was about fighting fires, Budney enhanced the ominous effect of a wisp of smoke blowing under a door with a version of a coyote howl. One of the classic examples of such sound enhancement, he says, comes from the first three Star Wars movies, in which fighter aircraft screech with a modified camel’s call.

Ranft says his library, too, gets plenty of requests beyond the bounds of science. Birdcalls are becoming increasingly popular for cell-phone rings, and psychologists ask him for recordings of wasps and bees to use when people undergo therapy for insect phobias. Ranft has also supplied wasp recordings for treating a phobic dog.

Like librarians everywhere, Budney gets requests that don’t fit into any category. He’s no longer thrown by people begging him to send someone over immediately to record Sasquatch. Years of experience with “raspy screechings late at night,” usually from midsummer until November, lead him to inquire whether the caller knows the sound of a juvenile great horned owl being weaned.

However, Budney says he did enjoy the challenge of a series of phone calls, starting with one from Minnesota, describing “little wailing sounds in the walls at night.” When the third person called the library, Budney responded that someone in the household must recently have acquired a particular model of watch from Radio Shack. “The fellow was absolutely incredulous,” Budney recalls.

At some settings that model’s alarm went off on a default schedule with the oversimplified, hard-to-recognize sound of a rooster. The sound moved around the house because people had left the watch in different places on different days.

Rogue watch alarms aside, people can invent remarkable artificial sounds. However, even Rydstrom, a master of designing artificial universes, says, “I don’t think we can synthesize as interesting a sound with computers as the ones the natural world can create.”

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Susan Milius

Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.

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