Tuesday, 27 July 2010

Grey Shrike-thrush (Colluricincla harmonica)

It is a very cold morning,  I've hung out the washing and I'm cleaning up the kitchen.  As I was standing at the sink,  I looked out of the window to see this Grey thrush singing beautifully.

There are a couple of them around,  no doubt a pair.  They regularly nest in the garage where their song echoes like a voice in the shower!  The description of the call in my bird book is  a liquid melodious"pip-pip-pip-ho-ee"  and I'm sure that they have read this too.
The book shows a male and female,   and I think that this was the male.

Australian birds are opportunistic breeders (rather than seasonal, as in migratory European birds,  for example.)  Many Australian birds are long lived and their behaviours are best understood by reading the literature about primate behaviour rather than the more traditional "bird" literature from Europe.  The traditional literature describes behaviour that involves migration, pairing up for the spring breeding season, flying "south" for winter and relatively short lifespans.  Australian birds often breed after rain....  not only the huge flocks of water birds inland...  but also the smaller seed and insect eaters that are able to take advantage of the flush of growth following the infrequent and unpredictable rains.

It has been suggested that birds have evolved from a form that might have been found in Gondwanaland, the precursor supercontinent.  It has been suggested that these forms might have been more like the Australian native birds that are longer lived,  often "hanging out" with the same individuals for a relatively long time and breeding opportunistically and cooperatively.  Even small native birds live much longer than the typical few years of European birds that find the cold northern climate and consequent migration more life threatening.  Even the tiny blue wrens that are so beautiful and popular subjects for artists and photographers can live as long as 25 years or more.

While this is interesting in terms of evolution,  survival of the fittest and life strategies, it can also prove to be a trap for management of wildlife when civilisation and settlement impinges on habitats.

Many people don't notice the problems for wildlife until numbers are significantly reduced, particularly with the relatively more common bird species.  It is only when one realises that one hasn't seen a particular species for some time that the alarm might be raised.  With longer lifespans,  this can be less noticeable until numbers are quite low.  In fact the huge reduction in relatively long-lived and common species is truly alarming...  species like willy wagtails, magpies and thornbills are all around,  though very much reduced in recent years.

And so my resident songbirds are much appreciated and I enjoyed the serenade at the sink.

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