It was at Bowra in July assisting Dean Bortelli with his Hall's Babblers
project. Hall's and Chestnut Crowned Babblers were common and in medium
sized groups in the main 10-13 birds perhaps, although I tracked a group of
3 which Dean was quite surprised at. On my last day I came across 2 Grey
Crowned Babblers and despite watching them for a while appeared to be on
their own? Had not thought a lot about that until this thread appeared.
Cheers
peter
-----Original Message-----
From:
On Behalf Of Russell Woodford
Sent: Friday, 3 August 2007 3:35 PM
To: Birding-aus
Subject: Grey-crowned Babblers (Brisbane)
Sorry that I can't give a reference, but I recall an article (Emu?
Wingspan?) some years ago that reported a threshold size for viable
breeding colonies: I think that once the colony falls below 6 birds
they cannot maintain their population. I'm not sure whether this
study was about GCB or White-browed, or all babblers, but it doesn't
suggest a promising future for them if there numbers are getting this
low.
Russell Woodford
Birding-Aus List Owner
Geelong Victoria Australia
http://www.birding-aus.org
On 03/08/2007, at 6:32 AM, Greg wrote:
> Speaking of Grey-crowned Babblers there is a general consensus
> amongst birdos in the Clarence Valley, north-coast NSW, that the
> average flock size of this species has declined over the past 20
> years or so. It is based on anecdotal information only so I was
> wondering if it appears to be the case in other areas. Flocks of 2
> to 5 are more common now than larger flocks. It may be related to
> the carrying capacity of disturbed habitats.
>
>
> Greg Clancy
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