BIRD SONG

Forest and Bird, Issue 96, 1 May 1950, Page 15

BIRD SONG

OOETS used to think that birds sang from the sheer joy of living: modern scientists, however, think otherwise. Maybe high spirits sometimes have something to do with it, but it is much more likely that their singing has some definite purpose, such as to warn other birds off their own little patch of territory, or to attract a mate. Injured birds have been known to sing and that can hardly have been from joy.

Birds sing most during the nesting season, probably first to establish a territory and sing defiance to other males who might feel disposed to trespass on it, and then to advertise “an eligible husband for disposal.” The cock will go on singing to his mate on the nest during the nesting season, at the same time warning off intruders, but he will not go too near the nest for fear of giving its position away: the hen would probably drive him away if he did.

Most birds have an alarm note —short and sharp —which will either cause other birds to scatter or sometimes to band together for attack. Tuis, for instance, will sometimes band to attack an intruder, such as a hawk, and believe me the hawk generally goes-—quickly!

Swamp birds such as duck and pukeko when feeding usually post a sentinel to watch for danger —they can then keep their heads down with a feeling of security. When he senses danger the sentinel will begin to utter a series of low squawks, to put the others on their guard; when the danger comes too close, up he goes with the others after him.

The art of singing is confined almost exclusively to what are known as “perching” birds —that is, birds that perch in trees or shrubs. Sea birds, waterfowl and ground birds generally have only a harsh note. This is probably because the perching birds, being at a later stage of evolution than the others —more highly civilised, so to speak—have more highly developed throat muscles.

The tui has a whispering song, when, though you can see his throat muscles moving, you can only hear a faint whispering: it has been suggested that the notes of this song are pitched so high in the scale of sound that the human ear cannot hear them.

A morepork has other notes than the familiar “morepork.” When making love he will settle himself on the same bough as his lady, making low, gurgling noises. He will gradually edge up to her, and she will edge away until she comes to the end of the bough, when she flies off to another perch. Whereat he will give a loud, indignant “More-pork!” as if to say, “Drat the woman, what’s the matter with her!” and .follow her and start again.

The time when the sheer joy of living rings out in the notes of the birds is when they greet the new day in their Dawn Chorus —I wonder if you feel that way when you are turned out in the morning !—but now, alas, the Dawn Chorus which at one time was one of the wonders of N.Z. is only heard in isolated parts, and then only as a ghost of its former self.