The Northern Cardinal for many of us is that first blaze of color after a long winter. They begin to sing in the late winter, early spring and you you see that male Cardinal dashing across your yard to take up a posting and sing its brilliant whistled song. The song of a cardinal is actually fairly simple. It’s a series of whistled syllables. Usually each song is comprised of one to two, sometimes three, syllable types. One component of a cardinal song that often goes overlooked, but if you listen carefully you can actually hear, is a churr or purring that occurs at the end of the song and it’s much softer than the actual whistled notes and they don’t always give it. [Female Northern Cardinal] A female Northern Cardinal is as adept as a male at singing. Often this goes overlooked because we assume it’s only the male’s that sing, but if you listen carefully, if you watch you may actually see and hear a female singing. Humans use their voice box to produce sound. We’re only able to produce one sound at a time. Birds use another type of organ called the syrinx and it’s located right where the two bronchial tubes come up from each lung. It’s a paired structure it has two sides to it that are equivalent in their ability to generate sound, and a bird actually can produce one sound on the left side and another independent sound on the right side. When a cardinal sings a beautiful upward sweep whistle it’s actually using the left side to produce the lower portion of that whistle and without any obvious break to us as human beings it produces the higher pitched portion of that whistle with the right side, just amazing physiology involved in sound production. To see a flash of red and then these fantastic bursts of clear whistled song, it’s one of those invigorating things that signals the transition from late winter into early spring. [Audio Recordings: Gregory F. Budney, Wilbur L. Hershberger, Gerrit Vyn; Photographs: Gerrit Vyn, Marie Read]

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While the human voicebox can produce only one sound at a time, a bird’s syrinx is a paired structure that allows birds to sing complex, fast-paced songs. Located where the bronchial tubes from each lung come together, both sides are equally capable of producing sound. They can be used in concert to sing two different notes simultaneously and to complete broad sweeps in pitch quickly. In the Northern Cardinal, the left side of the syrinx produces the lower pitch portion of the sweeping notes, while the right side produces the higher pitch portion. Studies of a number of songbird species have shown that potential mates listen closely to song quality and cue in to small variations when distinguishing desirable mates from those who don’t quite have the chops.

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