Call is one way of IDing
these guys, but after you have seen both species, I feel that they definitely
have a different ‘jizz’ and tone to the
grey of the upperparts. This
however, is a relative thing, and takes a little practice, but I feel that it
can be ‘conclusive’.
I’d suggest the nasal groove is a
tough one to get, your eyes will probably explode before
you see this feature in the field (except through really expensive optics at
very close range). In my experience
(which is by no means exhaustive with either of these species) grey-tailed do tend
to hold themselves more horizontal (similar to a terek
sand), have a lighter more washed out grey tone to the upperparts, and the
supercilium is generally prominent well past the eye. Wandering tats tend to hold themselves
more upright with a longer necked stance (greenshank-ish),
have a far darker grey tone to the upperparts, and the supercilium is generally
far less prominent. They seem to be
a bit more long legged in the field to – as far as measurements go,
however, the difference in tarsus length is in the realm of millimetres
(according to HANZAB), so is probably more an artefact of the birds stance.
Still I guess this won’t help conclusively
with your ID problem Brian….just my thoughts.
[ On Behalf Of Keith Brandwood
16 January 2003 1:49 p.m.
Subject: [BIRDING-AUS] grey or
Hi everyone, Brian, I believe the only way you can ID these
two species is by call, or the extent to which the nasal groove extends down
the bill, and you need to be close up with a scope to see this feature.
supercilium, plumage colour and extent of wings past tail tip are not
conclusive in my opinion.