On Thursday, July 17, 2008 3:36 PM
"Chris Brandis" <>
Cc: "birding-aus" <>
asked
Mike
Could you point out to many of us why this is a Little Stint and not a
Red-necked Stint in partial breeding plumage.
I think I know the answer from a field guide of Kenya, but just to
confirm, as the Aus. field guides are a little vague.
Thanks Chris
Hi Chris,
I agree that the current Australian field guides are somewhat inadequate on
this matter which is why we need a more comprehensive one. I perhaps could
have answered your query but instead hand passed it to a real expert. Gosh,
it is nice to have competent friends! Here is what he had to say.
From DANNY ROGERS:
"Thanks (?) for forwarding this inquiry. Here are a few notes on why the WTP
bird is such a nice example of a breeding-plumage Little Stint.
Perhaps the first point to make in a discussion of how this bird can be
separated from a Red-necked Stint in partial breeding plumage is that the
WTP bird IS in full breeding plumage. The amount of breeding plumage in
different feather tracts of waders is strongly correlated. The upperparts
are a good place to start looking, as the feathers there are nice and big,
allowing one to examine individual feather patterns when you've got a scope,
or photos of the standard taken by Jeff Davies and Peter Fuller of the WTP
bird. Just about all of the upperpart feathers of this bird are breeding
plumage: big blackish centres and rufous edges or fringes are obvious. There
are two inconspicious lower scapulars (overhanging the folded wing) visible
on the left side of the bird which are predominantly grey with blackish
shaft-streaks and have been retained from non-breeding plumage. Everything
else is breeding plumage. It's fresh and natty breeding plumage given that
it is mid-July, so I suspect that this bird carried out its pre-breeding
moult a bit later than is typical for the species: perhaps that's why it
isn't in the northern hemisphere right now. (In addition, it might be
wearing
fairly slowly as it's experiencing long nights down here and hasn't been
exposed to 24-hour daylight). Looking closely at the upperparts you can also
see that some breeding feathers are less brightly coloured that others - a
few of the scapulars and tertials have browner centres and less extensive
rufous markings on the edges than others. That's pretty typical of breeding
plumage of sandpipers (the first-grown feathers tend to be a bit duller in
colour than those feathers grown when the pre-breeding moult is in full
swing), and it's helpful for the birder, as it enables us to separate this
bird from
an absurdly early fresh juvenile. Juvenile stints can be very brightly
coloured when they are fresh and have just arrived in Australia, but as
they've grown all of their feathers simultaneously, the patterning and wear
of the upperpart feathers is very uniform.
Given that we are looking at pretty much complete breeding plumage, there
are quite a lot of characters that point to Little, rather than Red-necked,
Stint. (All the following comments on plumage apply only to breeding
plumage). The extensive white throat is one of the most obvious features -
in full breeding Red-necked Stint, this area is mainly rufous (as the name
suggests), though there is usually a small white chin, and this marking can
encroach onto the throat to some extent. Moreover, the rufous of the throat
and breast in the two species is rather different. In Little Stint the
rufous of the sides of the face (including the lower lores) and breast is
always overlain by fine dark speckles and streaks. In Red-necked Stint the
rufous bits of the face and throat are a little darker (sort of brick-red
when fresh, more orangey in Little Stints) and they are predominantly
unmarked. Immediately below the rufous throat of a Red-necked Stint there's
a gorget of nearly-black streaking or speckling on a white background, most
boldly defined at the sides of the upper breast. Little Stint doesn't have
that gorget effect, and the rufousy ground colour extends onto the sides of
the breast.
Another feature I like on the WTP bird is the black tertials with rufous
fringes to most feathers (very broad indeed on a couple of the tertials).
Red-necked Stints in breeding plumage usually have greyer centres to the
tertials, and narrow whitish to buff fringes to these feathers. Occasionally
one or two feathers may have rufous edges, but they are narrow and don't
dominate the appearance of the rear-end. Another reliable feature is the
inner median and greater secondary wing-coverts - black-centred with rufous
fringes in Little Stint, almost invariably plain brownish grey in Red-necked
Stint (a minority of Red-necked Stints will replace one or two of these
feathers). The WTP bird had its scapulars drooped over the folded wing when
Jeff photographed it, so these helpful feathers cannot be seen in his
images. However, the bird raised its scapulars and drooped it's wings
slightly for Peter Fuller, enabling him to take images which show that all
the exposed inner greater secondary coverts (about 3 feathers) and median
secondary coverts (at least 7 feathers) were just right for Little Stint.
There are a number of other Little Stint features on this bird which are
subject to more variation, or are fairly subjective to assess. But
considering them all together, they too support the identification. Broad
creamy mantle V is typical of Little Stint; it can be present in Red-necked
Stint, but it's usually much narrower, and it's usually only present in very
fresh breeding plumage. In Little Stint there is often an effect of a "split
supercilium) - at the front end of the broad white supercilium, there is a
small second white lateral crown stripe (a lateral crown stripe) running
above the main white supercilium. This effect isn't really clear in the WTP
bird, but it's hinted at by the expanded white front of the supercilium and
is more consistent with Little than Red-necked Stint. The extensively rufous
general appearance to the upperparts is better for Little than for
Red-necked Stint, in which the upper scapulars usually stand out as the most
extensively rufous area of the upperparts.
Finally, there's structure. As the name implies, Little Stint is slightly
smaller than Red-necked Stint. There is overlap in size between the biggest
(female) Little Stints and the smallest (male) Red-neckeds, and in general I
don't think the size difference is easy to see in the field. But I'm told
that the WTP bird is conspicuously smaller than the Red-neckeds it is
hanging around with. Little Stints also tend to have a finer tip to the bill
than Red-necked, and are more likely to have a slight decurve to the lower
mandible; they tend to have a smaller head, with flatter forehead, and a
crown that looks narrower when seen from head-on; they tend to look a bit
more leggy and upright (Red-necked Stint is proportionately longer-legged);
and they tend to look shorter bodied (the rear end of Red-necked Stint looks
more attenuated). These features can all be seen in the WTP pictures.
Structural features like these have to be used cautiously, as both species
of stint can be quite deceptive, with variation in condition or changes in
posture influencing our perceptions of their jizz. You'd need a lot of
experience, persistence, luck and fantastic views to pick out a non-breeding
Little Stint on structural features alone! But the fact that all of these
features look good for Little Stint in the available photos tend to support
the identification."
Mike Carter
30 Canadian Bay Road
Mount Eliza VIC 3930
Tel (03) 9787 7136
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