Sines of the Thymes

[martin butterfield <>]

Geoffrey

It is interesting that according to GBS data - see attached - in a couple of recent(ish) years (24 and 25) there was not a single Fan-tailed Cuckoo reported in the Survey in Winter, Spring, Summer or Autumn.  (I haven't yet looked at the earlier years when the values of A were much higher than a present to examine the seasonality but will do so shortly.) While it may be claimed that this doesn't reflect what is going on in the bush there are enough GBS sites within spitting distance of such areas as Mount Ainslie, Aranda Hill, Black Mountain and Isaacs Ridge to suggest that if the birds were common someone would have reported them. 

I strongly suspect something is going on but I don't think I have ever suggested any reason for this: not climate change nor the GDE nor anything else.

Its a great pity that your Survey from last is not going to be repeated.  To say that additional data will merely lead people conclude that there has been another atypical year is taking a very dark view.

On Fri, Apr 8, 2011 at 10:08 AM, Geoffrey Dabb <> wrote:

Oh dear, I don’t think I can take this any further.  I have repeatedly put my view that Ft Cuckoos are present and call throughout the Winter.  Over several past years I have often heard them eg at orienteering locations all over our woodlands.  In order to demonstrate this, I suggested for last Winter  a tallying of this and other species, and I reported the result to this list.  Now Martin and others say that that result only indicated the (possibly unusual) presence of the relevant species last Winter.  They are quite correct.  That is all that it shows, but it is also consistent with the species being present in all Winters, or in most Winters, or in other Winters that were like last Winter in some respect.  If I repeated the exercise for the coming Winter, those of the narrower view would say that presence has only been shown for two years, and correspondingly if the exercise was repeated for 20 years.

 

It is quite true that species-presence does vary, sometimes markedly and sometimes for the long term, eg  Crested Pigeon, Koels (query whether long term).  No doubt changes are occurring right now.  Each of us has their own views on what is going on.  If it came to the point, I don’t suppose I would want the evidence on which I base my own perceptions subjected to a rigorous scrutiny.

 

I only raise this because ‘únusual’, expressed or impied, is the adjectival comment that comes with many reports to this chatline.  That’s fine.  The reader can regard the report as unusual or not depending on their own experience and researches.  However the cumulative implication of all this is that SOMETHING IS GOING ON, the assumption by many being that this is something associated with climate change.  Perhaps that is indeed the reason for some unusualnesses, perhaps not.  Then again the reported behaviour might not be so unusual after all.       

 

From: martin butterfield [
Sent: Friday, 8 April 2011 8:01 AM
To: COG List
Subject: [canberrabirds] Sines of the Thymes

 

Two Fan-tailed cuckoos calling at Carwoola this morning.  Ever the optimists.  Perhaps the birds are going to hang around this Winter as they did last.

One regular event in the colder months is the appearance of flocks of 10+ Noisy Miners in my GBS site.  The first of those turned up this morning, clearly demonstrating why they are not called Silent Miners.

Martin

110408 FTC.xls
Description: MS-Excel spreadsheet

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