I agree with David: when worn, Latham's Snipes look relatively pale. The
buffy bits of their plumage bleach to cream or off-white, and the dark bits
of their plumage look increasingly brown (rather than blackish) because more
of the brownish feather-bases are exposed with wear.
Although I've banded plenty of snipes, and examined lots of museum skins
when preparing a HANZAB text on Latham's Snipe, I've never seen a one that
was known to be in its second year. I thus can't rule out the possibility
that very pale individuals like the one at Banyule are second-year birds. My
impression though is that second-year snipes are indistinguishable from
adults. Latham's Snipes are unusual among Australian waders in that they
complete a post-juvenile moult (including primaries) at almost exactly the
same time as the complete post-breeding moult of adults. Second-year snipes
are thus likely to be at a very similar stage of wear to adults, and to be
similarly dark.
One possibility is that the Banyule bird was in its first year, about 5-6
months old, in worn juvenile plumage (which grows in about July as the bird
moults out of natal down). Such birds do often appear more bleached than
typical adults (which moult body feathers twice a year, once about the time
of northwards migration, once during the Australian summer). Confirming the
age in the field would be very difficult. You might get somewhere, given
superb views, if you could detect the subtle difference in pattern of
retained juvenile wing coverts (sketches are provided in HANZAB). Such first
year birds also start their primary moult slightly later than in adults (in
Oct. or Nov., cf. usually September in adults) and their outer primaries are
not quite as worn as in adults. These differences are quite difficult to
pick up in the hand by December, and I've never managed to see them in the
field.
Danny Rogers
At 01:26 PM 26/11/98 +1000, David Geering wrote:
>
>My experience of banding snipe in NSW, over 100 banded last summer near
>Newcastle, are that the palest birds handled almost invariably have very
>worn plumage. The birds are moulting while in Australia. It could be that
>the very pale birds are those in their second year, that is, they might
>have retained that plumage longer than older birds.
>
>Danny Rogers may have more to say on this?
>
>David Geering
>
>
>
>
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