|
Yes
Mark's first point about Pyracantha,
Cotoneaster and ivy is
contained in other sources. Where I first learned about it from or most
memorable to me, is the article: Birds, berries and bad bushes, by Michael
Mulvaney 1986 in CBN 11(3): 94-99. It is what I meant from
my earlier comment about "is more due to the increased around the year
availability of food (especially fruits and berries), that has allowed more
Currawongs to survive through the year and maintain territories locally and thus
be ready to breed". As in that is by no means my research or discovery I was
just referring to someone else's work. Although the suggestion
then made by Michael about the Currawong, is being backed up by evidence far
more now than in 1986. Together with the trees idea from Dennis and perhaps more
locally breeding small birds, they make good suggestions.
With
Does your father's book talk about that? I was
actually referring to habitat change and influence on a whole lot of species,
not just the Currawong.
Philip
Denis
is right with his summation of events leading to the Pied Currawongs becoming a
permanent fixture in the city and suburbs. The other thing that has triggered
their stay is/was the planting of shrubs such as Pyracantha, Cotoneaster and
ivy, among others. I know there are quite a few people who blame currawongs for
the loss of many bird species around the suburbs and in the fringing nature
reserves. I know currawongs take young birds [that is part of what they are
designed to do] but so too do magpies, kookaburras and even, in the right
habitat, swamphens and Musk Ducks. I regularly have currawongs visit my back
deck and they quite happily leave little presents all nicely bundled up!! I have
NEVER found anything but plant material or insect remains in these presents. I
do have a major problem, in what passes for my garden, now with species such as
those already mentioned and others such as privet. It would be an interesting
study to get the ACT Government to declare all these berry-bearing bushes as
noxious weeds and demand they be removed, but that will never
happen
In
my opinion one of the main reasons for the reduction in numbers of small birds
in and around Canberra one only has to look at the ACT Governments attitude to
acacias of different species. I have seen perfectly healthy stands of such
species as Black Wattles totally removed from areas around Kaleen/Giralang. With
all due respect to those who lost or suffered damage to houses during the 2003
fires, this is a classic knee jerk reaction to something the Government doesn’t
understand. Of course drought is the other contributing
factor.
Any
other long term residents care to comment – I came to Canberra in
1954?!
Mark
From: Denis
Wilson [
Sent: Sunday, 12 August 2012 5:46
PM
To: Philip Veerman
Cc: Mike Braysher;
Subject: [canberrabirds] Re: Pied
Currawongs migration changes
Hi Philip and
others.
Dad's book simply records a report by Marchant (1965) that
"a few pairs stay and breed around the City. ("Birds of the ACT - Two centuries
of Change)
There is no attempted explanation, merely reportage. My
comments are conjectural, of course (which I have already
acknowledged).
However, the early photographic record for Canberra does
bear out my comments about the history of early plantations in Canberra. The
late, great Lyndsay Pryor was responsible for most of those plantings. http://en.wikipedia.org/wiki/Lindsay_Pryor
Your
comment about Black Mountain having been largely cleared is also correct. Once
again verifiable by photographic record.
However, in my understanding is
that the bulk of the current Black Mountain "forest" is not really suitable
breeding habitat for the Pied Currawongs. It is dense Eucalypt regrowth forest,
but the understorey is sparse, and largely dry. Much of it is Bursaria shrubbery
with large areas of native grasses. Whereas, the ANBG plantings are much
favoured by Pied Currawongs.
That could be because the people at the
ANBG have managed to replicate a wet forest habitat, with a dense
understorey, whereas most of Black Mountain is either Scribbly Gum/Brittle Gum
forest with dry shrubbery understorey, or else, on the southern side, mostly
Stringybark with some Bursaria scrub understorey.
The so-called "rain
forest gully" in the ANBG provides a great breeding habitat for Pied Currawongs
and a full suite of small birds, insects and reptiles. A complete
habitat.
The Currawongs of Telopea Park are but a mere 30 second
flight from established gardens, replete with young Blackbirds (thanks Geoffrey
for the "evidence" of that food source) and other small
birds.
Cheers
Denis
On Sun, Aug 12, 2012 at 5:10 PM, Philip Veerman <>
wrote:
Thanks, good comments,
good logic and seem a very likely additional contributor. Requires a bit of
background of early knowledge to think of that one though. Were there really so
few big trees around here several decades ago? A program on TV maybe last year
talked about how Black Mountain was mostly open grassland with few trees and
showed several early photos that certainly support this idea. I would think then
that this change would impact on numbers of many other species of woodland /
forest birds. Does your father's book talk about that? Maybe there is that
evidence. I don't know, it is before my time here.
I have taken the liberty
to change the subject header and taken off the earlier messages - a useful thing
to do, to get off this Myna article.
-----Original
Message-----From: Denis Wilson [
Sent: Sunday, 12 August 2012 4:36 PM To: Philip
Veerman
Cc: Mike Braysher;
Subject: Re:
[canberrabirds] The Common Myna: 'Is It Benign or Is It a Pariah?' Comment on
Mike's message.
Hi Cog Chat line
members
Now that the subject appears to be drifting to Pied Currawongs, I
can offer the comment that the first records of breeding of Currawongs in
Canberra of which I am aware, came from an "egg collector" (pers comm, as they
say in official journals), in the early 1960s.
The location of that
"first Currawong's nest and egg collection" was Telopea Park circa 1961. Telopea
Park was one of the oldest established plantations of tall Eucalypts, in
the early days of Canberra.
Subsequently they became established in
Forrest, and then the ANBG as those areas developed enough tall Eucalypts for
the Currawongs to breed in.
The supply of succulent nestlings in the ANBG
is a matter of record, courtesy of the extensive studies of Superb Fairy
Wrens there by the ANU students.
But in my personal experience, it was
the presence of established tall Eucalypts which enabled the winter-visiting
Currawongs to remain in Canberra over the summer, in suitable breeding habitats.
The suggestion of available high-protein food (notably nestlings of
other birds) as the causal link risks putting the Chicken before the Egg - in my
opinion. Two sides of the equation are necessary, I agree, but the thing which
changed in or around 1960s in Canberra was the maturation of the early Parks and
Gardens plantations of tall Eucalypts.
Denis Wilson
Denis
Wilson
"The Nature of Robertson"
www.peonyden.blogspot.com.au
--
Denis Wilson
"The Nature of Robertson"
www.peonyden.blogspot.com.au
|
