That
is interesting. Looking at GBS data, which is of course only consistently
available complied for the first 21 years, the spread of observations of
breeding is very wide over time of year. Though very little information
really. Note that for the first 12 years of GBS there were no established
codes for recording of nest building, inspecting hollows, etc. The few records
in that time were all from contributors who participated for many years and had
their own codes. Nearly all autumn & winter observations are DY (or F) (no
doubt young of the previous year). There are very few spring & summer
observations of breeding and can be of any stage. There are no records that
suggest an actual nesting within the GBS area or come remotely close. Most are
just isolated occurrences of something on just one or two weeks at a site.
Mostly this sort of nest building, inspecting hollows type behaviour and DY.
Though Geoffrey's obs is earlier than others within that earlier period.
Here is the relevant bit of GBS Report
text.
Gang-gang Cockatoo Callocephalon
fimbriatum
................
Breeding records have also increased, first
recorded in Year 5 then most years since then. Most records are of dependent
young. These can be at any time of year, though most are from March to July.
Philip
-----Original Message-----From:
Geoffrey Dabb [ Sent: Sunday, 4 August 2013
10:55 AM To:
Subject: [canberrabirds] The
Canberra Gang-gang
The time of year when pairs of gang-gangs can be seen in the
early stages of nesting behaviour, but it is unlikely those local hollows will
be used. Rather, this is ritual bark-chewing and mock-house-hunting,
probably part of a bonding process before they head for the hills to engage in
serious nesting. This pair has been at it most days this week on Rocky
Knob
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