At 21:58 11/02/98 +1000, you wrote:
>
>Subject:
>
>Recently there was discussion of the possibility of the dawn chorus being
>missed in advance of bushfires. I now raise another aspect of birds
>possibly reacting ('pre-acting'?) to oncoming weather.
>
>I spend most Wednesdays working as a volunteer at the Australian Rainforest
>Conservation Society. The ARCS office is in the Brisbane suburb of Bardon,
>at the edge of a small patch, perhaps half a hectare, of Eucalyptus forest
>with rainforest understorey. On several occasions last year, I thought I
>heard an Eastern Whipbird _Psophodes olivaceus_ (they do occur in some
>Brisbane suburbs) but wasn't sure. Just a very rare single 'whip' call..
>But on Wednesday 28th January, there was no doubt: a pair were calling and
>answering, loud, clear and often. It was a hot sunny morning but by noon
>storm clouds were gathering and before 1 pm the deluge started and we got a
>couple of inches in a very short time. It was the first heavy rain in
>Brisbane for quite a while.
>
>The following Wednesday, March 4, and again today, I heard no Whipbirds.
>They may call at dawn, but after 9 am, only very rare calls (or none),
>except on that one day in advance of the heavy storm rain. It's hard to
>escape the conclusion that the two events were connected.
Dear Syd,
I read your posting with interest since I've been interested in the seasonal
& diurnal pattern of forest bird calls. A study I did a few years back
(Emu 97:121-125) showed that E Whipbirds had a peak of calling from c4-10 am,
then very little until a "pre-sleepies" peak at 6 pm. The results come
from 10 days of dawn-dusk observations in Brisbane Forest Park over summer
(Nov-Feb 1992-93).
This seems the general pattern but your suggestion of weather induced calling
could well be possible.
The E Whipbirds differed from the other two species I looked at (Noisy Pitta
and Green Catbird) in that their calls showed far less seasonal variation,
ie they had a fairly constant rate of calling throughout the year. This is
based on walked transects (4-5/month, 1991-94, in Brisbane Forest Park).
I guess this might be to do with holding territories all year??
>Anyone care to comment?
>
>And does anyone know of any proof that it is the male whipbird that
>initiates the duet? Peter Slater (of the University of St Andrews, not our
>Australian Peter Slater) tells me that Rachel Levin of Cornell University
>has shown (using laparotomy) that in the case of Bay Wrens _Thryothorus
>nigricapellus_, a monomorphic species in Panama, it is the female that
>initiates the duet. And I note that in the book "Bird Song - Biological
>Themes and Variations" that Slater co-authored with C.K. Catchpole, they
>illustrate and discuss the whipbird duet but avoid saying which sex makes
>the 'whip' and which the response.
>
>
Here, you might like to look at the work by Michael Watson, 1969.
Significance of antiphonal song in the Eastern Whipbird Psophodes olivaceus.
Behaviour 35: 157-178. There is no doubt that the "whip" is the male song
and the
second part of the duet is by the female. An interesting fact to come out
of his work is that the male's song showed little geographical variation
and the female song which showed much geographical variation. This was
a very thorough study, based in Vic but with recordings from SE Qld.
>I'm sure everyone who subscribes to birding-aus, wishes for the long-term
>survival of all forest bird species. If you are reading this and you don't
>already actively support the Australian Rainforest Conservation Society,
>please consider doing so.
>
>Aila Keto, the ARCS President has probably done more than any other
>individual to preserve Australian native forests; she has certainly done
>more than anyone else to preserve Queensland rainforests. Virtually
>single-handed, she persuaded the Queensland Government to stop logging
>rainforest on all Queensland State Forests. Dr Keto is presently working
>extremely hard to try to preserve an acceptable level of biodiversity, on a
>sound scientific basis, in the native forests of south-eastern Queensland.
All power to the Australian Rainforest Conservation Society.
Without forests there would be no forest birds to study or enjoy!!
Yours
Peter
Dr Peter Woodall email =
Division of Pathobiology
School of Veterinary Science Phone = +61 7 3365 2300
The University of Queensland Fax = +61 7 3365 1355
Brisbane, Qld, Australia 4072 WWW = http://www.uq.edu.au/~anpwooda
"hamba phezulu" (= "go higher" in isiZulu)
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