HI Mike thanks for advising me of this discussion, I must admit that I have
long been an advocate of resurrecting the taxon "immaculata" as being the
Australian representative of E. garzetta. The reason for my holding this
opinion being that, over my many years of regular acquaintance with Little
Egrets in the Pilbara, I never once saw (at least amongst all of the ones seen
well enough to check such details) one single bird that did NOT show yellow on
the soles of the feet - this in direct contrast to the entirely black toes of
"nigripes", a taxon with which I was, at that time, already familiar. This
characteristic was present at all stages. Even on - green-legged - juvenile
birds the soles still showed up as being of a slightly "more yellow" shade,
with this character becoming more obvious as the leg-colour darkened and
finally "blackened" into that of an adult bird. In adults, this yellow areas
seemed to vary in neither extent nor in shade of colour, whether they were in
breeding plumage or not. I will admit, however, that none of the birds I saw
there ever displayed the reddened facial skin colouration of the "courtship
blush" and so I cannot comment on whether, over that period, the soles of the
feet would, correspondingly, redden, or not - as is the case in the nominate
form. I would, however, suspect that there is a good possibility that they
would do so. In fact the illustration in "The Herons Handbook" - Hancock &
Kushlan, does indicate this as being the case. Such "courtship" reddening" is
however a "short-lived" event and altho'(if the soles do in fact attain that
colour) birds seen in this state could easily be taken as having "all-dark"
toes: I suspect that this factor would not account for all of the "Top End"
observations/comments. I would, nevertheless, be interested to hear what was
the corresponding colouration of the facial-skin, eye etc. when the toes were
noted as being "completely and uniformly dark".
As to the basic query - what sub-species of Little Egret is present in the "Top
End"- well that obviously comes down to whether one accepts the taxon
"immaculata" or not. If one does then I would consider that there is a good
case for these birds being of the form "nigripes". I'm afraid that gleaning
details of the distinctions between the two taxa will be difficult.
"Submergence" (of "immaculata") will have resulted, as is usual in such
instances, in the indiscriminate "lumping/combining" of records; as such the
process of sorting out which comments refer to which taxon will, now, be all
the more difficult.
Personally, I would not be too surprised to find that "nigripes" has indeed
turned up in the "Top End", after all there are already records of the far more
geographically distant - nominate - form arriving in Australia. There are,
also, undoubted "pressures" on many wetland areas within Indonesia, which would
probably provide a sufficient "push-factor" for their "local" birds to move
away from traditional breeding areas and to attempt to relocate wherever they
can. (Why not Australia?) Whether, if this is the case, they will be able to
maintain this extension/invasion , be "pushed-out", or "integrated" into the
"immaculata" populations is an interesting prospect.
Regards, John
-----Original Message-----
From: Mike Carter
Sent: Tuesday, 16 October 2012 9:40 AM
To: Niven; Robert Inglis; Birding Aus
Cc: John Darnell
Subject: Nominate Little Egret at WTP on Birdline
HANZAB reminds us that formerly there were two subspecies of Little Egret in
A'asia, nigripes and immaculata. Some of us would prefer that situation
restored as there are differences between populations, which may include feet
colour.
Mike Carter
30 Canadian Bay Road
Mount Eliza VIC 3930
Tel (03) 9787 7136
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