Bird Song
By Dave Hanks
Song is a very important means of communication amid the various displays a bird exhibits. Songs can fill a wide range of sounds, from the harsh screech of the Barn Owl, to the ugly croak of the Great Blue Heron, to the very appealing song of the Western Meadowlark. In most cases it is only the male that sings. However, the Cardinal, Song Sparrow, Rose-Breasted and Black-Headed Grosbeaks are some species where the female will sing. When male and female sing at the same time (duetting), it strengthens the pair bond.
Song has two major functions. One is to warn other males to stay away from the singer’s territory, and the other is to advertise to possible mates. The quality of a male’s song is one determining factor in female mate selection. The primary song fills the needs mentioned above, but there is also a much quieter and simpler (secondary) song given at the nest. Its function is unknown. Red-Winged and Yellow-Headed Blackbirds give a wing display while in the act of singing, and every species has its alarm call, used when a perceived predator is in the area.
Birds that live in open country usually sing while in flight. The flight song is generally accompanied by aerial maneuvers. WINNOWING is a type of song caused by air rushing through the wings as the bird does his aerial acrobatics. The Common Snipe is a prime example of this, and his winnowing is easily heard on a spring morning. DRUMMING is another variation of communication. The Ruffed Grouse does it by sitting on a hollow log and flapping his wings. Woodpeckers do it by pecking rapidly on resonate tree trunks.
One interesting aspect is that birds in different geographical regions have different dialects, even though they are of the same species. Also, young birds sing a less elaborate and much quieter song version of their parent’s song. Some species have a wider range of singing ability and can even imitate other species. The Mockingbird is the most notable – being able to imitate up to 30 species (on record). Learning the different birds by their songs can be intriguing, but it is much harder to master than visual identification.
(A Blue-Winged Warbler: Warblers are noted singers)
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