Fledgling Wattlebird

["Michael Lenz via Canberrabirds " <>]

Early Red Wattlebird fledglings/Koel

Red Wattlebirds raise more than one brood per season (quite regularly 2, in some cases possibly 3). And to quote from Veerman (2003) [GBS Report for 21 years]: "The breeding period is long with considerable overlap of nest period and the time that young are dependent ... with dependent young from late September till end of February."   With Koels generally arriving by mid October in Canberra (eBird bar chart for ACT)  it seems that first broods of Red Wattlebirds escape from being parasitized. Things could only change if Koels were to arrive much earlier. 

Holland (2026) [CBN51(1) 91-94] writes: "My observations of Eastern Koel ...fledglings between mid December and mid February...correspond very well with the observations across the COG Area of Interest, with only one before and very few after this period." This would indicate that it is mainly the 2nd Wattlebird brood that is parasitized. Additional nests may become available for the Koel if wattlebirds with failed nests try to raise a replacement brood.

There is no advantage for a Red Wattlebird in nesting very early as a "strategy to avoid being parasitized". But it may increase the chances for an extended breeding season and a pair may succeed in raising more young (3 broods).

Michael Lenz

On Sun, 9 Aug 2026 at 22:44, Philip Veerman <> wrote:

It is interesting to think about these ideas of Red Wattlebirds maybe bringing breeding earlier, to get a brood in before the Koels arrive. To me, on face value that seems to suggest a very intelligent strategy (a bit excessive for a bird), so any change could be due to other things (as Michael suggests). And yet if viewed as an adaptive strategy and thus not intelligence but just random choosing of a change of behaviour that happens to give an advantage, it seems to have been evolved incredibly rapidly. There are lots of cuckoo species around the world (and other brood parasites) and there are also a range of strategies used by the different host species. And yet as Micheal writes, the word naive also fits, as the RW would appear to not have much of an anti Koel strategy (apart from nest defence). Maybe this is just a conundrum of word use within us trying to understand the brains of birds. I am not suggesting I know.

 

Philip

 

From: Michael Lenz
Sent: Sunday, 9 August, 2026 4:32 PM
To: Philip Veerman <>
Cc: Terry Munro <>; Matthew Larkin <m("hotmail.com","mblx55");" target="_blank">>; COG list <m("lists.canberrabirds.org.au","Canberrabirds");" target="_blank">>
Subject: Re: [Canberrabirds] Fledgling Wattlebird

 

Early Red Wattlebird fledglings

 

This winter has been quite mild, and suburbia is in general a bit warmer than surrounding non-urban areas. Further, some suburban sites may provide good food sources: e.g. winter-flowering native plants + supplementary feeding by people. In response to these factors birds may respond with early breeding.

Also by all accounts, the Red Wattlebird is still a rather naive hosts to the Koel as the high number of young Koels fledgling from Red Wattlebird nests  attests (see Jack Hollands latest article on this subject: Canberra Bird Notes 51(1) 2026, p. 93-94).

 

Michael lenz

 

On Fri, 7 Aug 2026 at 18:27, Philip Veerman via Canberrabirds <> wrote:

Page 106 of The GBS Report provides the graph (and the text on page 69) of the breeding timing of the Red Wattlebird (and other species), so addresses the timing issue. But this is only for the first 21 years of the GBS (1981 to 2002). There has been (little or) no attempt to keep the information consistent, available, compiled or up to date since then.

 

So yes, it certainly is very early but not without precedent. The suggestion of this being to beat the Koels has been put forward often over the last few years. And appears to be a nice idea to explain what could be happening. There can be lots of factors that can influence timing of breeding (or changes of timing). A comment a few days ago about magpies jumped at the idea of climate change.  Note that Koel had not yet been recorded breeding here within the period of The GBS Report (page 61), even though my text shows that I expected it would happen soon.

 

Philip

 

From: Canberrabirds On Behalf Of Terry Munro via Canberrabirds
Sent: Friday, 7 August, 2026 5:21 PM
To: Matthew Larkin <>
Cc: COG list <>
Subject: Re: [Canberrabirds] Fledgling Wattlebird

 

Is this “early” fledging of a Wattlebird to beat the arrival of Koels & their  effect on successful WB breeding

Terry Munro

 

On Fri, 7 Aug 2026 at 12:41 pm, Matthew Larkin via Canberrabirds <> wrote:

One very recently fledged Red Wattlebird in Cook this morning, tracked down after hearing begging calls.

Matthew Larkin
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