Birding by Ear

Birds of the Galapagos Photo Gallery

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When it comes to finding and identifying birds, sound can be as important as appearance. Learning to recognize bird sounds will increase your enjoyment of birding enormously.

Birds make a variety of sounds with a variety of purposes. The most recognizable bird sounds are the lovely notes warbled by songbirds, but virtually all birds (swans and vultures are among the rare exceptions) have songs of a sort and make other sounds called vocalizations. All bird vocalizations are produced by the syrinx, an organ located in the trachea just above the branching of the bronchi leading to the lungs. As a rule, the more developed the syrinx, the more complex the sounds it can produce. Songbirds generally have highly developed syrinxes and thus produce the most complex song. Interestingly, because the song is produced entirely within the syrinx, many birds can sing with their mouths full or even closed.

Every songbird species has a distinctly different song, full of rich harmonics. Birds outside the songbird family also produce distinctly different calls and other sounds that are an aid to identifying the species and to determining where the bird is and what it is doing. For example, it is visually difficult to tell the difference between a lesser and greater yellowlegs unless two birds are near each other for a size comparison. However, the voices of the two species are quite different and easily distinguished.

Songs

Birdsong or vocalization, whether complex or simple, is a male function, designed primarily to define territory. Another significant function is to attract a mate; this accomplished, the male sings to his mate to strengthen the pair bond. (With rare exceptions and despite all the inaccurate poetry about nightingales, female birds do not sing.) The same functions of birdsong are accomplished in other ways by some other birds. Woodpeckers, for example, define their territories and attract females by drumming on resonant surfaces such as trees (and sometimes houses or even cars).

Birdsong reaches its peak in the early mornings of spring, when male birds are vying for territory and advertising for mates. A bird walk through woods and fields at this time of year is a delightful cacophony of sounds. Singing drops off noticeably once the birds get organized, with all the borders staked out and females spoken for, but it continues at a reduced level into the breeding season. By midsummer, birdsong almost ceases.

Singing birds in the spring are easy to find just follow the sound to the tree branch or shrub that contains the singer. The birds will generally be found perched prominently on the tops of the trees, at the ends of the branches, or on top of other vegetation or telephone poles, the better to project their voices, keep an eye on the competition, and spot any interested females. Singing birds generally adopt erect postures, with the head back and the beak wide open. They thoughtfully repeat their songs loudly over and over from the same place, allowing birders to home in.

As part of claiming their territory, some birds such as cardinals will counter-sing or duet with nearby rivals. When this occurs, first one, then the other bird sings alternately. Once you realize that at least two birds are involved, you can separate the sounds and go in search of one or the other.

Locating a singing bird can be difficult. The first step is simply to stand still and listen intently, concentrating on only the bird you are tracking. This can be surprisingly difficult, especially for city dwellers who are accustomed to ignoring all the undifferentiated noise constantly around them. It can also be difficult for older birders, who may no longer be able to hear very quiet song or the high notes. Try turning your head slowly from side to side while listening; you should hear the bird more loudly toward one side or the other. All members of a group should listen carefully and slowly point to where they think the sound is coming from. Theoretically, this should yield an accurate consensus. There's a good chance, of course, that just when you think you have located the bird it will fly away. Stick with it. Generally, a territorial bird won't fly far and you still have a good chance of getting a look at it.

In general, birds sing the most in the early morning and toward dusk. Some birds, including some flycatchers and swallows, sing special dawn songs just before day breaks. The function of dawn songs, aside from their beauty, is unclear, unless they are an incentive to birdwatchers to get up early.

Other Sounds

Particularly among songbirds, a distinction is generally made between songs and other sounds. Male, female, and young birds all produce a wide range of calls and other sounds that help the birder locate and identify them. Generally, a bird's repertory of sounds falls into several convenient categories: alarm calls, contact calls, flocking calls, feeding calls, begging calls, flight calls, aggressive calls, and non-vocal sounds such as woodpecker drumming. Unfortunately, these sounds are often not as well-defined as songs, making it difficult sometimes to determine which bird is making the sound and why.

Especially to inexperienced birders, the various chips and chirps made by different birds sound much alike. With practice, you will gradually begin to recognize the more obvious differences among species. Some differences are so slight as to be virtually undetectable; in such cases, even experienced birders need other clues to identify the bird.

What a particular bird sound means must often be determined from the context. For example, the contact call (the sound members of a pair make to keep in touch with each other) of the white-breasted nuthatch is often described as yank or yank-yank. The same call, given louder and more frequently, is an alarm call.

Learning Bird Sounds

A unique sort of vocabulary is used by the authors of field guides and other written descriptions to transcribe bird sounds. When reading descriptions, the easiest to remember and imagine are those that are onomatopoeic, or imitative of the actual sound. A classic example is the chicka-dee-dee-dee call of the black-capped chickadee, which sounds exactly as it is written. Other songs and calls are not as easy. Songs are often described as melodious, clear, whistled and slurred. Calls may be described as a harsh chatter, buzzy trill, or rattle call. Songs and calls are also often transliterated as a burry teeooo, raspy chur, or a simple chip, tseep, or even ik or chjjj. Even worse from a beginner's standpoint are descriptions that compare one bird's song with another's, since you are likely to be unfamiliar with both. And what exactly is the difference between sounds that are buzzy, burry, and raspy? Are birds that go chjjj also found on Klingon?

Beginning birders can take comfort in the knowledge that the experts disagree among themselves about how to describe and transliterate bird sounds. For example, Roger Tory Peterson renders the song of the Acadian flycatcher as"a sharp explosive pit-see," while other guides render it variously as PEET-sah, Peet-suh, and flee-see; the usual mnemonic is Pizza!

No amount of puzzling over the correct pronunciation of tsickajwee-jwee (tufted titmouse) or woika woika (red-bellied woodpecker) can ever substitute for hearing the real thing. Ideally, you will locate and identify a new bird, hear it vocalize, and forever remember the sound and associate it with a clear mental image of the bird. The association can be complicated by some variables. Many songbirds sing individual variations on the basic song, and individual birds sing variations of their variations. Some birds do good imitations of other birds -blue jays often imitate the screams of hawks, and the mockingbird's song consists of nothing but imitations of other birds. In addition, the basic song can vary by geography. In effect, birds develop dialects. This is often noted even by casual birdwatchers when they hear song sparrows in other parts of the country. Finally, birds make lots of simple call noises that sound a lot like those of other birds. Remember that even the most experienced birders usually know only the usual territorial song and most common call sounds for a species. When all you hear are assorted chips, you might as well give up on an aural identification. Use the sounds to locate the bird for a visual identification instead.