Hi Jeff,
I have not seen the Asian subspecies in the flesh but from the numerous
photos that I have seen I can't tell the difference between the two
subspecies on plumage colouration. I, also, don't agree that Australian
birds are necessarily greener than Asian birds. I examined a recently dead
Stork in direct sunlight and its black plumage had a very blue sheen all
over it, apart from the purple crown. Examining the same bird under the
artificial lights of the Australian Museum the sheen was clearly a green
colour. For this reason when Walter Boles advised me that they were
considering describing the two races as separate species I was not
convinced that this was warranted. I only changed my mind when he told me
the results of the genetic analysis. The two samples were genetically quite
distant, strongly suggesting that speciation has occurred. As one specimen
was of unknown provenance Walter and Les decided to defer splitting the
species until further genetic work is carried out.
Clearly with the Black-necked Stork more genetic analysis is needed but if
further work supports the limited existing evidence then a strong case for
separating the races as species can be made. I am not convinced that just
because they look superficially similar that they can't be separate species.
Bassian and Russet-tailed Thrushes look similar from a distance. It would
be good to be able to closely examine the museum collections of both
Australasian birds and Asian birds to see if there are subtle plumage or
morphometric differences.
There is presently very little plumage and morphometric data available on
the species in either region. I have gathered a little during the past few
years and the specimens held at the Australian Museum are also a source of
this data..
Greg Clancy
Ecologist
Coutts Crossing
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