birding-aus
Hi birders,
I've noticed a bit of variation in fledged juveneile Koels. One bird I saw
in Townsville in '95 was black & white: white head with black mask and
malar stripes, black and white checkered upperparts and white underparts
finely barred black. Nothing at all like the illustration in Slater x3, but
more like the adult female except with a juvenile head pattern. I've never
looked at museum skins, which can unravel many mysteries. I've assumed
that juvenile and female koels are highly variable and that this has been
overlooked in field guides. It is even possible that they have 2 or more
definable morphs.
Overlooked variation is pretty common in field guides. So to is the
mislabelling of plumages as "imm" or "female" when they are not. Simpson &
Day's illustrations imply that "first year" Black Kites are paler and
redder than adults without the adults pale face. Slater illustrates "imm"
plumages of frogmouths that are just adults. Whats a female plumaged rufous
whistler with a pink bill? or a female plumafed fibird with a pink bill and
orbital ring or one with brown bill but olive back and wings like a male?
You can't age and sex lots of species using the field guides. Some, like
atherton scrubwren you can't even identify safely. Field guides can't and
don't cover everything. I don't mean that our guides are bad. In fact I
think they are excellent, especially considering how few articles have been
written on identification of Australian birds that field guide authors can
source. But they are not handbooks.
The Field Identification section of HANZAB attempts to redress this
imbalance between the reality of variation in birds and the practical,
portable synthesis presented in field guides. I don't think this role of
HANZAB is yet widely appreciated, to provide, where possible, the
information necessary to identify age-classes, sexes and subspecies in the
field with some degree of reliability founded on original research. But
yeah, its hard to read, it can be a complicated tangle.
I'm looking forward to seeing HANZAB on cuckoos. I think most of the
Plumages texts were written by Danny Rogers, so we can expect that they'll
advance our knowledge of this group by leaps and bounds.
Cheers,
David James
PO BOX 5225
Townsville Mail Centre 4810
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