On 5 January Lawrie Conole wrote :
> Pied Currawong dialects seem quite extreme, and even allowing
>that I have not heard the Lord Howe one, I suspect it would be no more
>remarkable than the variations of the mainland population - any
>comments??
To which Jim Davis responded:
>I have also noticed distinct regional dialects of Currawongs.
>Assuming that this specie is highly social and probably learns much of its
>vocal repertoire, it isn't surprising to find that birds in
>different population use dramatically different sounding calls, etc.
>However, it would be very interesting to determine if there
>is an underlying pattern to sounds (similarity in structural components of
>calls) common to all populations. I would predict that the calls which
>are most strikingly different are those that are sexually selected (i.e.
>females used to select a mate etc.). There is currently, intense interest
>birds. The currawong would be a good species to study. I hope you find
>my comments of interest.
Lawrie commented:
>I suspect that this is probably the case. The basic "curra-wong" call
>structure is still somewhat recognisable in different regions, though
>the duration of the parts with respect to each other varies. The sound
>of the call varies considerably, but the structure less so, thus
>explaining vernaculars such as "currawong", "chillawong", etc. Perhaps
>then the western Gariwerd birds should be called "guddabangs"?? The
>ones around home are certainly "currawongs"!
and suggested some more questions to be answered:
>Do Pied Currawongs from different dialect groups recognise each other as
>Pied Currawongs? Do they have any opportunity to do so? Some
>populations are already relatively isolated geographically, eg. those at
>Gariwerd from the main Great Dividing Range some 70-80 km east, and
>maybe this leads to particular local distortions, though there may be
>some intermixing of altitudinal migrants & wanderers in Winter (cf.
>non-breeding time) on the plains between.
Currawongs first drew my attention to the existence of regional dialects in
bird song, when in '48 I found the voices of the population near Tully
Falls in north Queensland so noticeably different from those of my home
area of Tamborine Mountain in southern Queensland. I reckon the difference
with the Lord Howe Island population to be even greater, but that's just a
subjective opinion. We need a study, as Jim suggests. I haven't
searched the literature (and don't intend to) but suspect that we don't
even know for any population, how the calls are used - what they mean to
the currawongs. One of the less musical calls on LHI which I've never
heard on the mainland seemed to me to be associated with nest defence, but
I haven't enough evidence to be sure of this. (And I didn't manage to tape
it.) Tamborine Mountain folk-lore, 60 years ago, held that a currawong
corroboree meant that rain was coming ... but in such a high rainfall area,
perhaps that was likely by chance anyway.
Anyone looking for a research project? There should be a PhD in currawong
vocal behaviour for someone.
Cheers
Syd
H Syd Curtis
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