Surely the white on the rump feathers is at the tip of each feather and
not the base. That would be easy to check from museum specimens. If that
is so, it is not possible for a white patch to appear in time after the
black shows, as the tip of each feather appears first. So I cannot work
out how it is possible for "the bird that I saw earlier but it has now
grown a bit of white on its base of tail". Unless those feathers with
the white tips grow after the lower feathers have matured. This would
seem a bit odd but it is a possible explanation for those few birds that
show this feature. It surely is Pied Currawongs we are talking about not
Greys so we can forget that aspect. The feature is not that uncommon and
probably just some variability in the speed at which these feathers grow
or variability in the length of time during the growing of these
feathers from the point at which the switch for no pigment changes to
start pigment.
Philip
-----Original Message-----
From: Tun Pin ONG
Sent: Friday, 22 January 2010 1:07 AM
To: Bruce Ramsay
Cc: Canberrabirds
Subject: Pied Currawong Markings
Hi Bruce and all,
I went to the same patch in Cook on Monday where I earlier photographed
the 'uniform-rumped' Currawong. Did not see any Pied Currawong with such
feature. But I saw one with 'dotted line' of white spots along base of
tail. Another one with 2 white patches of white at the sides of the base
of tail. At least 2 others with typical white crescent at base of tail.
If it is both Frank and Bruce's suggestion that this is some
transitional plumage for subadult, then perhaps one of them was the bird
that I saw earlier but it has now grown a bit of white on its base of
tail.
I have seen a photo of Dark form Grey Currawong from Handbooks of Birds
of the World (out of range from Canberra), where this dark form does
look very similar to the typical Pied Currawong, and the bill of this
dark form of GC is slightly thicker, hence make it even closer to PC.
Hope this generates some interests in otherwise very common and dull
looking backyard bird. If the feature of 'uniform-rumped' in Pied
Currawong has been documented anywhere, please let me know. Thank you.
Regards,
Tun Pin ONG
On Thu, Jan 21, 2010 at 6:19 PM, Bruce Ramsay <>
wrote:
> The other day Ong Tun Pin wrote in regarding the absence of white at
> the upper tail base (considered in Field Guides to be indicative of
> Grey Currawong) of a presumed Pied Currawong that he had seen and
> photographed in Canberra recently.
>
> Frank Antram replied on this chat line (others may have responded to
> Tun Pin privately - I don't know) that he felt the bird was probably
> an immature Pied Currawong and not a Grey Currawong. And not an
> aberrant form or a bird suffering from feather disease.
>
> I would just like to confirm Frank's intuition ?(maybe personal
> observation?) with a direct observation. I have just had a young Pied
> Currawong in the bird bath in our back garden here in Gordon. I am
> confident that it is a Pied because it has been fed (and is still
> begging vociferously) by adult Pied Currawongs. It seems certain it is
> their offspring. I was unable to get a photo but clearly saw the
> bird's back. It too has no white at the upper tail base.
>
> I don't know if this is a feature of ALL juvenile/immature Pied
> Currawongs (I suspect not). And I don't have access to a HANZAB so I'm
> not able to check there to see if it notes this feature and how
> widespread it may be.
>
> But it now seems certain that SOME juvenile Pied Currawongs in
> Canberra (the bird Tun Pin photographed and the one I have just
> observed here, at the very least) do not show any white at the upper
> tail base.
>
> Hope this is of some interest.
>
> Regards,
> Bruce
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