'Baer's Pochard' ringer at Werribee was a Hardhead
My evidence for the above conclusion is as follows.
By courtesy of Chris Lester (see also his posting on 30.07.04), I have now
seen just four of the many photos taken by Tom Fletcher of the purported
Baer's Pochard seen on Lake Borrie at the WTP on 7 July 2004 following the
reported sighting by Fred Smith four days previously. The reported greenish
gloss on the head doesn't show but this is probably because the photos were
taken against the light and in any case, is of no great significance. The
whole of the right side appears to be bright rufous with some darker brown
showing through near the folded carpal, (apparently partially cloaked by
feathers at the side of the breast, i.e. wing tucked in). There are some
pale vertical streaks in the flank area. This side pattern is very strange
for a Hardhead but neither does it fit a Baer's. On Baer's, there is more
white forward (i.e. at the side of the breast) and less aft, the reverse of
this individual. The broad white subterminal band on the bill, well defined
on both edges, is absolutely that of a Hardhead and wrong for a Baer's. On
that species the band is half the width and merges on the proximal edge. A
pale longitudinal streak on the side of the bill might be construed to fit
Baer's better but pale sides to the bill also appear in photos of Hardheads,
see e.g. p. 204 in Nat. Photo. Index, 'Waterbirds of Australia'. There
appears to be no strong contrast in shade between the head and breast,
(horizontally at the base of the neck), as should show in Baer's. I am also
concerned by the fact that the white belly patch is bordered by dark brown
across the vent, a feature of Hardhead I suspect not replicated in Baer's.
Another disturbing feature is its size (thank you Sean Dooley for drawing my
attention to this). It appears that the bird was the same size as adjacent
Hardheads. Baer's is similar in size to Grey Teal and therefore should be
about 10% shorter than a Hardhead (45 rather than 50 cm long).
Since it is far from convincing as a Baer's Pochard, parsimony
says that it's a Hardhead. Incidentally, the wings of this bird were also
frayed indicating it was the same individual as the one later photographed
by Peter Fuller.
I'd be interested to hear other opinions and any criticsms of the above
analysis.
Mike Carter
30 Canadian Bay Road
Mt Eliza VIC 3930
Ph: (03) 9787 7136
Email:
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