Are wattlebirds getting smarter? i.e.CHOOSING to breed earlier to avoid the Koel?
I don’t suppose I have ever though that saying Wattlebirds are getting smarter is anything other than a casual way of saying that Wattlebirds are
EVOLVING, selecting the earlier breeders as survivors.
Manyo f us use phrases like ‘getting smarter’ but I think we mostly mean evolving. It is hard to imagine a Wattlebird pair DECIDING to breed earlier
because they understand the future possibility of Koels abusing them.
From: Philip Veerman <>
Date: Wednesday, 30 August 2017 at 2:59 pm
To: 'Virginia Abernathy' <>, 'Jack & Andrea Holland' <>, 'Mark Clayton' <>, chatline <>
Subject: RE: [canberrabirds] are Red Wattlebirds getting smarter
Thanks Virginia for your comments. Obviously there are a huge number of potential factors involved. A quick look at The GBS Report (page 69 and graph of breeding
timing on page 106) indicates that even with what Mark reports, there is nothing new about the Red Wattlebird
starting breeding this early in the year. This was occurring within the time period 1981 to 2002 covered by The GBS Report, before there was any breeding of the Koel in Canberra. Yes being on the nest at the end of August was then within the early range but
not unknown. One observation does not of itself show the suggested change. Of course if there are many, rather than few, such observations now, in 2017, that may show that something of a change really is happening. But to get consistent data is the issue.
This further highlights that The GBS Report needs to be updated, as the GBS is the most consistent ongoing data set we have. As I have written many times.
As for RW getting smarter, if the trend is indeed true, that is one possibility, Virginia mentions others, or it could also be an evolutionary change favouring
those individuals that breed earlier.
Here are the relevant texts from The GBS Report:
Red Wattlebird Anthochaera carunculata
Our most conspicuous honeyeater, it is noisy, bold, active and aggressive. This species being a resident and the largest and most rambunctious honeyeater, may take over a site that provides a rich food supply and exclude
other species. It is among the most recorded species in the count and the breeding list. It is common all year.
…………………
There are some early observations of nest building or copulation in late June or in July but most breeding records start after early August. Most records are of dependent young, rather than activities at nest. From
the few records that chronicle a whole breeding event, the duration is from 10 to 12 weeks. The breeding period is long and with considerable overlap of nest period and the time that young are dependent. There may be more than one breeding pair simultaneously
at many sites, there is also a strong suggestion of double nesting. Mostly activities at nest have ceased by end of December with dependent young from late September till end of February with a few observations as late as early April.
Graphs on pages: 90 and 98, Rank: 6, Breeding Rank: 3, Breeding graph on page: 106, A = 2.00051, F = 97.36%, W = 52.0, R = 74.847%, G = 2.67.
Common Koel Eudynamys scolopacea
………..
No breeding records - yet.
Philip
From: Virginia Abernathy [
Sent: Wednesday, 30 August, 2017 11:27 AM
To: Jack & Andrea Holland; Mark Clayton; 'Canberrabirds'
Subject: Re: [canberrabirds] are Red Wattlebirds getting smarter
I had several wattlebirds in Canberra that starting nesting right around this time or earlier and in Sydney I had one with a fledgling at the start of August! Without more study its hard to say whether
wattlebirds are adapting to koels by breeding earlier or this may just be a byproduct of weather/temperature changes.
From: Jack & Andrea Holland <>
Sent: 30 August 2017 09:37
To: Mark Clayton; 'Canberrabirds'
Subject: Re: [canberrabirds] are Red Wattlebirds getting smarter
Mark, the Red Wattlebird (RWB) is an early breeder, as evidenced by the data on its bird info page of the COG web site. This shows nest building starting in June and both nests
with eggs and with young from July. Personal experience is of young fledging in late July 2004, the month we returned home in Chapman after January 2003 bush fires (see write up in CBN
30, pp97-116 (2005). This was in a still bare and devastated garden.
Having watched and published on Koels, including breeding, closely over the past few years I believe many RWBs are already on their second brood by the time Koels arrive in October,
and they mainly parasitise the third RWB brood for the year as the Koel fledgling period is mainly in the second half of January and February. This is also when many RWB fledglings are around.
As will be described in the paper I am preparing for CBN on the 2016-2017 season Koels do seem to be changing their behaviour with for example females arriving or at least being
conspicuous much earlier than in the past. Also the RWBs may be learning, in areas where there have been many fledglings in the past such as Page Barbara Allan’s close observations have revealed there have been very few in the past couple of years.
Sent: Wednesday, August 30, 2017 8:51 AM
Subject: [canberrabirds] are Red Wattlebirds
getting smarter
Morning all,
We are still a little way off hearing from our “favourite” spring/summer visitor, the Pacific Koel, which gives the local Red Wattlebirds such a hard time when the koel finally
arrives. This morning I noticed a wattlebird disappear into a tall Melaleuca in my front garden. A quick visit to the bush showed a wattlebird sitting on a nest, obviously trying to get at least one clutch through before the koels arrive in the neighbourhood.
This nest is generally a lot earlier than I have previously noted so are the wattlebirds adapting to the time when the koels are here? It makes one wonder!
Also on nests at present are one of the local Australian Magpie groups and the local Australian Ravens have been seen carrying sticks.
Mark
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