On Mon, May 25, 2009 at 06:24:07AM -0700, Rob Geraghty wrote:
> I'm not sure if it's me that is confused or the wren I saw today.
> After having observed male Superb Fairy Wrens going from breeding
> to non-breeding plumage over a month ago, today I saw a male in
> breeding plumage!
> Do some males just stay in breeding plumage all year round?
Timing of moult into blue plumage is extremely variable in SFWs.
Long-term studies in Canberra Botanic Gardens found it occurred anywhere
between March & November and it was strongly affected by age. 4+ year old
males moulted March-August, 1st year birds males September-November and
2nd and 3rd years were in between. The timing of the moult out of blue
plumage was less variable, occurring January-March. A few males (14% one
year, 0% another year) moulted directly blue plumage -> blue plumage.
One of many papers about CBG SFWs here: http://tinyurl.com/rddl2o
So based on the Canberra data, and it may not hold elsewhere, a male SFW
in blue plumage in May is likely 4+ years old and moulted in the past
3 months. Perhaps directly blue-blue but more likely via brown plumage.
Andrew
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