This is a reply of interest to others that I received from Syd Curtis.
---------------------- Forwarded by Frank O'Connor/Argyle on 20/11/97 06:05
AM ---------------------------
on 19/11/97 05:08:44 AM
To: Frank O'Connor/Argyle
cc:
Subject: Re: tapes/mimicry
>I have replied because I wondered what the response was
>to birds that use mimicry such as lyrebirds, orioles, etc. Does the
>imitated species come running???
>
>Frank
You've raised a very interesting topic, Frank. The simple answer is that
no the other species do not come running. So why not?
Aren't the imitations good enough? Yes they certainly are. Lyrebirds can
copy almost any sound with great accuracy. And as you no doubt know, quite
poor tape recordings or inferior human imitations can call in a lot of
species.
There are two reasons why another species does not react to a lyrebird's
imitation of its call.
Firstly, when birds do react to playback it's because the bird is
territorial and it's defending its territory. This is mainly associated
with breeding and out of the breeding season the bird won't react.
Lyrebirds (both species) are winter breeders and the species whose calls
the lyrebird is using are not. They are mostly silent when the lyrebirds
are in full voice. Logrunners and Eastern Whipbirds do breed in winter in
the Albert Lyrebird area, and it is noticeable that their calls are not
included in the Albert Lyrebrd's breeding-season song.
Secondly, the lyrebirds use only short sequences of calls of other species
which they put into a largely continuous stream of sound. It is apparent
to a human listener that this stream of sound is all coming from the one
source, and so it is likely that this is also apparent to other species -
almost certain, in fact, for playback of lyrebird song will often bring up
species that regularly dine at the lyrebird's table: they know it's a
lyrebird and that he is turning over the litter and soil and there will be
pickings of soil/litter fauna too small for the lyrebird to bother about.
Len Smith in one of his excellent lyrebird books has a remarkable photo of
a Superb Lyrebird in the act of throwing away a Yellow Robin that got in
his way!
I have had Yellow Robins react in this way to playback of Albert Lyrebird
song. And I believe both Yellow Robins and Pilotbirds will do so with
playback of Superb Lyrebird song.
And before I'm taken to task for using playback, let me state my position:
that I believe a limited amount of playback is justified if it is used in a
way that leads to increased knowledge of the species or in some way assists
in its conservation. (Which causes a bird the greater distress - playback
or mist-netting/banding?)
Incidentally, the lyrebirds' breeding season song which includes so much
'mimicry', is learnt from other lyrebirds: they are not directly mimicking
the other species, though hearing the other species keeps the lyrebirds
copies true to the original models. Albert Lyrebirds weave the mimicry and
a few other sounds into a stereotyped song lasting about 50 seconds which
they cycle over and over - the "albertcycle". All the sounds come in
exactly the same order each time. And every male in a local area uses the
SAME ALBERTCYCLE. So they must be learning from older lyrebirds. With
Superbs the 'mimicry' is random, but I suspect that were one to go to the
trouble of listing all the mimicked sounds for each Superb in a lek area,
it would be found that all had the same list. Again learnt from older
lyrebirds.
Look out towards the middle of next year for an article on lyrebirds in
"Nature Australia", the nature magazine of the Australian Museum. I have
reason to expect that it will have photos of the Superb from Len Smith and
of the Albert from Glen Threlfo. If so, it will be worth buying just for
Glen's superb photos of this difficult species. (Until about 30 years ago,
it had never been photographed in the wild at all, so shy is it.)
Why not subscribe now, Frank, (if you don't already), and be sure of a
copy? It's a quality publication. Annual subscription (4 issues) $33
within Australia; two years for $63, three for $89. The toll-free number
is 1800 028 558. (At least that was the case when the Autumn 1997 issue
was printed which is the one that happens to be on my desk at the moment.)
Syd
H Syd Curtis
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