Thanks Michael. Various reasons of course. The point is that the koel, although not everyone’s favourite subject, may be a very good subject so far as recordable trends are concerned. (a) it
is relatively easily observed, especially the dependant young; (b) in our area it is almost exclusively an urban/suburban species i.e. not being found in woodland or forest, although possibly in orchards etc; (c) it is here by reason of a recent and continuing
southward expansion of its migratory pattern, and being highly mobile has a ‘choice’ whether to visit, and remain, in this immediate environment; (d) it is dependant on, and here because of, the Red Wattlebird, and as you suggest its breeding success depends
on favourable conditions for RWB pairs. Variation in calling is of interest because I believe it is related to presence or absence of females in particular locations, but we need to know more. The effect of suburban expansion of the Noisy Miner is of interest
to me, but perhaps best treated as a separate issue
From: Michael Lenz <>
Sent: Saturday, 29 December 2018 11:28 AM
To: Geoffrey Dabb <>
Cc: chatline <>
Subject: Re: [canberrabirds] Koels and related matters
Geoffrey,
interesting observations/comments.
The lack of Koels can have various reasons. This year their activity in North Lyneham is also rather subdued. Apart from Noisy Miners affecting the cuckoo host, the Red Wattlebird, it is the drought that will have had a significant impact
on red Wattlebird (and many other species) breeding (mostly via impact on their food supply, see also the message from David Rees today), and with current dry/hot weather, it doesn't look good for their current breeding effort.
For example on Lyneham Ridge the Red Wattlebird is still common, but I had only the odd record of fledglings for this season. Last year many fledglings were produced.
It will be interesting to see how many Koel fledglings will be recorded (in the hope that Jack Holland will again collate the numbers), my guess is far fewer than last season.
On Fri, 28 Dec 2018 at 09:46, Geoffrey Dabb <> wrote:
I have a few things to mention. This has been an unusual season in that I have had very few koels around the immediate area. There have also been few wattlebirds,
which I attribute to the aggression of Noisy Miners, at least 2 families of those having moved in about 5 years ago. I have seen miners chasing wattlebirds, koels and other bird species. A question is: why are miners here, when they are not in some other
suburban areas? I know the theory that they avoid areas with dense shrubbery (including, I suppose, dense garden shrubbery). I believe they are unusual, if present at all, in the Bot Gardens for example. I believe that the species is advancing, probably
having colonized this neighbourhood from Mount Mugga, via Callum Brae. I wonder if they will test acceptable limits of suburban gardens as the population builds up. I am seeing miners taking advantage of garden margins, typically advancing along lines of street
trees, where they can feed on foliage and under bark. They are certainly strong breeders.
A characteristic of this area is that it has a number of fairly open neighbourhood spaces, with poor shrub-level veg. Each has its families of miners. This
is what they like – spaces with scattered trees, like some schoolyards, and golf courses. Given that miners are so territorial, areas where they are dominant can be fairly easily demarcated. Shall we see more such areas, characterised by presence of miners
and absence of wattlebirds and koels, and other birds?
Even so, I have still heard quite a few koels from 100m or so away, meaning a couple of streets distant, possibly from places that are still miner-free. Perhaps
they are using richer gardens, nourished by deeper topsoil than left on the rather rocky upper suburban slopes. Yesterday I had a rare nearby male koel. This was a first-year bird with a mixture of fresh black and worn brown plumage. The record tends to
confirm my suspicion that Canberra is visited by a high proportion of young birds. Typically, the bird was evicted from its perch by a busy miner.
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