Wednesday, 2 June 2010

An iconic insect of the Australian bush

From my first day in Australia I have become familiar with certain sounds that you'd hear no-where else.  From the distinctive cry of the Pied Currawong Strepera graculina and the Australian Magpie Gymnorhina tibicen to the grating noise of the red wattlebird Anthochaera carunculata and of course the laugh of the Kookaburra Dacelo novaeguineae.   I have found some links to mp3s of these:
The ANBG has a few more calls of birds found in the gardens on its website here.

It is not just birds that make a distinctive noise in Australia, particularly in summer the bush is alive with the sound of insects - its that which really tells me (an Englishwoman) I'm somewhere 'foreign'!  King of these is the Cicada, which although not unique to Australia there are over 200 species of Cicada within Australia found in every corner of the country.  Over the summer we heard these very loudly, particularly when visiting Kangaroo Valley over Christmas where the noise they made was incredibly loud.

This is a sound file recorded in New Zealand of a Cicada - just imagine it multiplied by 1,000 and 10 x louder and you have the Australian bush in summer!

However, until now, I've not managed to see one of these large insects despite feeling surrounded by thousands at times.  At lunchtime I was walking down a less well-trod path in the gardens and at eye level I spotted a very strange looking insect, over 1 inch long.

 I quickly realised it was just a dry shell, the insect having undergone molt from the final nymphal instar to become an adult. The nymph would have been living underground then constructed an exit tunnel to the surface and emerged. Having climbed onto the tree where I found the shell (a wattle-leaved peppermint tree Eucalyptus acaciiformis) the nymph would have split open the shell and flown away, leaving the skin behind clinging to the tree bark like a ghost.  You can clearly see where the shell has been split in my photo.  Here is a film of this event that I have taken from Wikipedia, it looks like an alien!

1 comment:

  1. Thanks to the links to the bird calls. My daughter LOVED listening to them and did pretty well at identifying them (for a three year old).