Sorry but it may be necessary to explain my last comment. To me just on first principles it seems a very odd thing to release a young Koel near to another young
Koel. Unless it has been proven successful by some prior strange event, it is the thing I would least advocate. The first thing every (parasitic) cuckoo chick does when it is hatched, is kill anything else in the nest. Normally that will be host chicks but
sometimes presumably another baby cuckoo (if it happens that one or more female Koels lay in the same nest). They don’t “like” company, that should be obvious. Their entire strategy is built around that. Is that going to change as they grow a bit older and
still partly dependent? Not likely. As common as Koel breeding is here now, the fledglings don’t choose to associate (well at least as far as I know) and why would they? They want to monopolise the feeding effort of the foster parents and they don’t want any
competition. So I would suggest that it is quite odd to suspect that putting them nearby would be appreciated by them. Again I would be willing to be surprised, if someone has evidence to the contrary, but just on my idea of logic, I doubt it. John did write:
I saw a juvenile Koel several times but I do not know which one I was observing because I did not see both at once. Even adults appear to spend a lot of their time fighting.
Philip
From: Philip Veerman [
Sent: Saturday, 29 February, 2020 6:56 PM
To: 'John Harris'; 'Canberra Birds'
Subject: RE: [canberrabirds] End of the Koel Saga
Hi John,
Sure interesting ideas and also Jack Holland’s input is very useful. I will add some ideas to both. There are occasional observations of parasitic cuckoos of
various species feeding fledgling cuckoos of their own species. Even though the parasitic habit is complex, maybe they still retain some of the basic instinct of a bird to stuff food into a big bright mouth, just enough to show the behaviour occasionally.
Although that is when the birds are still very young and not ready to migrate. Some cuckoos are not parasitic, so the child raising instinct is in there somewhere not all that far back in history. It is no surprise that the Red Wattlebird pair continue aggression
towards the adult Koels. It is one of the weird things that they recognise adults as a threat and yet still tend to fledged young that look by then really quite similar. In the meantime in your story it would be easy that the adult Koel would be attracted
to the same food source as the young bird was. Is there any meaningful interaction between the adult Koel and the young one? Hard to know. For me right now, I doubt it. There could be mutual curiosity: “What the hell is that!?” Maybe I should make some noise.
That is the thought if any, that I would expect, even if anthropomorphic. By analogy, in mound building birds where the parents display great devotion to the mound, they have absolutely no recognition of any chick that emerges, they are just kicked out of
the way. I would be surprised if the adult Koel has any role in guiding the migration of the young one. I am willing to be surprised. In most migrating birds young don’t follow parents in particular, though there will of course be many that do. Apart from
those that clearly do fly together, proving it either way is difficult. In the Channel-billed Cuckoo they sometimes migrate as flocks but for other cuckoos has anyone ever seen them migrating as family groups? I have not ever and suspect if so that it would
be odd.
As for imprinting, that is maybe the wrong word or if we use the word, it is a special different case. If cuckoos get imprinted in the way other birds do, then
they would direct their sexual behaviour towards their hosts, which clearly would be a mistake. However can it be that they get imprinted on the species that raised them to prefer them as hosts when they breed? That would appear to me to be likely. This is
why I raised the issue of the Regent Honeyeater host of the Pallid Cuckoo a few weeks back, as I was concerned this could be a problem, but the response I got was that this was a rare event.
About imprinting, it depends if there is any learned component in the vocalisation of these birds. On what possible basis would the baby Koel know to imprint
on an adult Koel, which for the most part will not be present (having long gone) but in rare cases such as yours where there happens to be a nice plum tree, will be there. That makes no sense to me. That it clearly does not occur in any other cuckoo that stops
calling before then, as jack mentioned, makes me think it is even less likely. The situation (lots of fruit trees to keep the birds nearby) in Canberra is also surely unusual and recent.
The gesture of
Wildcare released the juvenile Koel at my place sounds nice as a thing to do. Has this been done before? Is there more evidence about what happens? I am curious. Did it
have any practical value as distinct from releasing anywhere else where it could get a feed? I very much doubt that it had any real benefit to either bird and may I reckon more likely have caused distress to both, by being near each other for a time. Again
I am willing to be surprised. I doubt if anyone knows the answers to these questions yet.
Philip
From: John Harris [
Sent: Saturday, 29 February, 2020 4:12 PM
To: Philip Veerman; 'Canberra Birds'
Subject: Re: [canberrabirds] End of the Koel Saga
My recent Koel experience has made me very curious about the possibility of adut Koels mentoring juveniles. I am of course far from the first to observe such an interaction and there are suggestions that adults may be imprinting their call
or even preparing to lead the young birds on their northern migration. I should perhaps record exactly what I observed.
When I first reported the commotion in my plum tree, the male Koel was staying so close to the begging juvenile that I was briefly tempted to wonder if he was actually feeding it. After more careful observation over a few days, I saw the
Red Wattlebird pair feeding the young Koel. At the same time they kept trying to drive the adult Koel away. That is obviously a very strong instinct in Wattlebirds.
This aggression was the source of the commotion together with curious random birds coming to watch including Currawongs wondering if there was anything to predate.
The Wattlebirds succeeded eventually in driving the male Koel further away although he was reluctant, at first returning to the plum tree. He eventually gave in and hid himself quietly in a nearby tree. I could always locate him but only
because I knew he was there hiding himself. He made no sound.
I saw the juvenile begin to take fruit for itself. The Wattlebirds very soon stopped feeding it although it continued to beg. The Wattlebirds, however, then left and abandoned the young Koel to fend for itself. The male remained nearby
and began to call its wirra wirra now that it was no longer wary of revealing its presence and drawing the aggression of the Wattlebirds. The juvenile sometimes roosted in the tree where the adult was and returned to the plum tree.
It was at about this stage that Wildcare released the juvenile Koel at my place. For about another 10 days, the male continued to call wirra wirra and I saw a juvenile Koel several times but I do not know which one I was observing becauseI
did not see both at once.
I heard the last wirra wirra about a week ago. I presume them to have migrated north although it is also true that the plums have finished.
From: Philip Veerman <>
Sent: Friday, February 28, 2020 9:59:38 PM
To: 'Canberra Birds' <>
Subject: RE: [canberrabirds] End of the Koel Saga
It would indeed be interesting to know if adult Koels have a role in guiding or accompanying young birds on their first migration, their own young or even
unrelated ones. Given that they have no role in raising them (but it seems they stay in the vicinity), it is a tantalising and curious concept.
Philip
From: Denise Kay [
Sent: Friday, 28 February, 2020 7:56 PM
To: John Harris
Cc: Canberra Birds
Subject: Re: [canberrabirds] End of the Koel Saga
Wildcare have done a great job as usual , its not an easy job raising a Koel chick
On 28 Feb 2020, at 4:53 pm, John Harris <> wrote:
The dramatic saga of the juvenile Koel in my plum tree and the attending male waiting to guide its northward flight has a (sort of) happy ending.
People from Wildcare Queanbeyan read my posts. They had a rescued juvenile Koel which was ready to be released. When they read of ‘my’ juvenile Koel , that there was plenty of food here, and that he had a
guide waiting for him, they contacted me and came and released it in my yard.
I cannot honestly say that I saw the released bird after that. I saw and heard a juvenile Koel for about a week after that but do not know which one I was hearing or if it was both. I stopped hearing the
juvenile calls about a week ago, only the male wirra wirra.
I have seen or heard nothing for a week now. I presume they are on their journey north. I hope they make it.
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