Bird song focus of discussion at the Cary Institute

MILLBROOK — The hills are alive with the sound of male songbirds. For most of us, this persistent chirp, cackle, whistle and tweet is little more than background chatter, inconsequential and, in any case, indecipherable. But between birds, science has learned, it is richly communicative.Early in May at the Cary Institute of Ecosystem Studies’ auditorium in Millbrook, a standing-room-only crowd of bird lovers turned up to see and hear one of the world’s foremost ornithologists explain a bit about where bird songs originate and why birds sing the way they do. Professor Donald Kroodsma has spent his professional life listening and recording bird song by himself and with teams in a great variety of Western Hemisphere locations, from Saskatchewan to the Falkland Islands, and not a few places in the Tri-corner area. One welcome result is his volume, “The Singing Life of Birds,” which chronicles his life as an ornithologist.Kroodsma grew up in western lower Michigan. He was drawn to science but didn’t settle on ornithology until his last college semester, when he chose to study bird migration through the avian visitors to a local marsh. This led him to the marsh wren and what turned out to a lifelong fascination with this small, vocal bird — and a source of several important ornithological discoveries. Birders have a reputation for being rather quiet, studious, solemn folk. Kroodsma in prose and person is anything but. His book’s tone echoes that of his Cary lecture: eagerly inquisitive, self-aware (as scientists must be), single-minded and cheerfully persistent. The richest period of the day for capturing bird song is the hour from the first faint glimmer of light to dawn, often called the dawn chorus. Reading his fascinating book, it is easy to imagine arising well before this time to rendezvous with him on the edge of an Oregon meadow or the cattail marsh south of Tivoli before beginning several hours of painstaking recording and analysis.His pursuit of the marsh wren started, as all pioneering science tends to, with a fundamental question that no one had adequately answered: Why do birds sing? This soon led to other fundamental questions: How do birds become songsters? Why are bird songs different? What connects a bird’s song with its life experience? In more than 35 years of field and laboratory work to date, Kroodsma’s hard-won discoveries have deepened understanding of the natural world close around us and led to him being recognized by the American Ornithologists’ Union as “the reigning authority on the biology of avian vocal behavior.”Kroodsma’s methods have been simple, if laborious. In the field, he identifies a species he wants to study, locates several members, then records them until he is sure he has captured the full range of their repertoire — from fewer than a dozen songs for the common blue jay to, in an extreme case, more than 2,000 for the brown thrasher. His gear (as of 2007): A Sound Devices 722 recorder, a parabolic-dish microphone, headphones, a poncho, flashlights, binoculars and a Crazy Creek camping chair. An appendix obligingly discusses equipment with much advice for the beginner and amateur on a limited budget, and begins with a good-natured warning: Recording bird song “can become additive … don’t tell me I didn’t warn you.”Kroodsma’s discoveries have often involved differences indistinguishable to the untrained ear. Fascinated at one point by the eastern bluebird’s absence in the literature of avian song, he sets out to learn why. Since the first bird emerged 150 million years ago, avian species have multiplied until there are some 10,000 on the planet now. While new species occasionally emerge due to further genetic specialization, far more are lost because of habitat destruction, pollution, pesticides and global warming.“The Singing Life of Birds” is the impassioned report of a first-rate scientist determined to get to the bottom a fundamental question few others have asked. In a world — or certainly a country — where science is often misconstrued as a political agenda, Kroodsma’s life work is both a stirring reminder of the true value of science and an infectious summons to the pleasures and rewards of ornithology.Tom Parrett is a writer who lives in Millerton and Greenwich Village.