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to hear them is now when males establish and mark the boundaries of their breeding territories.
Songs are variations on an extended rattle or trill, some of them more mechanical than musical.
If. there are several singing males nearby, the differences among the songs are quite evident.
According to Donald Kroodsma (“The Singing Life of Birds”), each male chipping sparrow has only one song, and he learns it during the first breeding year from an older male.
Kroodsma estimates there are up to 30 versions of this repetitive trill available to learn.
He describes walking among the territories of several males during the breeding season and picking out the boundary lines from the noisy interactions that take place among the males.
Singing is serious business for a male because it tells other males where his territory is and lets nearby females know that he is available as a mate.
Older males are generally dominant and establish the most attractive territories. They also appear to win most border skirmishes with their
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