Friday, December 16, 2011

Blackbirds


Walking my dog today, I noticed that a few of the feijoas are flowering. The feijoas made me think of blackbirds, oddly enough.

The adult male blackbird is black, very black with blackish-brown legs, a yellow eye-ring and an orange-yellow bill. The adult female is in contrast is a sorry brown with a dull yellowish-brownish bill. The juvenile, is similar to the female, but has pale spots on the upperparts, and a speckled breast and are often mistaken for the song thrush. As the young birds mature, they may be seen with patches of black and brown. There are a lot around at this time of year, whistling in the undergrowth, hoping their parents will continue to feed them.


Unlike the thrush which sings through the winter, the blackbird remains silent until the spring when it becomes an annual competion among birders to record the first blackbird singing. The song usually ceases in December but has been heard as late as February. The blackbird's song is very much the largest part of the dawn chorus here in town and far out numbers the Tui's. Last summer there was a blackbird which persisted in singing at night on top of the old council building acoss the road, something to do with the street lighting, I suppose.


Ornitholigists have noted that birdsong uses the same musical scales as we do. Certainly many composers and poets have taken a great deal fom birdsong. Mozart had his pet starling and Beethoven his blackbird, which may be heard in the opening rondo of Beethoven's violin concerto in D, Opus 61. In many species it appears that although the basic song is the same for all members of the species, young birds learn some details of their songs from their fathers, and these variations build up over generations to form dialects. Living in towns and cities birds pick up other sounds as well and may incorporate them into their songs.

But I digress. I started out talking of feijoas which in their native South America are pollinated by birds. The blackbird, together with the myna, have learned the trick of pollinating them in New Zealand. Small birds, such as white-eyes, visit feijoa flowers but research here has revealed that they are ineffective pollinators.

I used to watch blackbirds from the kitchen window on my farm in the Bay of Plenty take apart the feijoa flowers, feeding on the sweet and juicy petals of the brightly coloured flowers, but have never seen them perform the same trick here. My blackbirds here seem to prefer cherries and grapes, while the feijoas languish and produce very little fruit. I'm curious to know whether or not anyone has observed them pollinating feijoas here.

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