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Red-necked Stint / Little Stint, Western Treatment Plant (Vic)

To: "Peter Shute" <>, "Birding-aus (E-mail)" <>
Subject: Red-necked Stint / Little Stint, Western Treatment Plant (Vic)
From: "Tim Dolby" <>
Date: Thu, 18 Jun 2009 11:36:29 +1000
Peter, that's because I got it wrong. If there wasn't any contradiction
it would be a Little Stint :-) However good question and as an
intellectual exercise I'm more than happy to analysis the error. I like
doing this sort of thing; you live and learn by mistakes.

I actually think you've asked the million dollar question in birding
i.e. what's the difference between the art and science of bird
identification. The simple answer is birders sometimes see what they
want to see. (Perhaps clouded by other things, such as a VicTwitch!)
This is probably what I did, unless there's another bird around, which
seems unlikely. I think someone would have identified and photographed
it by now.

In regards to the bird in the photograph on Birdline (see
http://www.eremaea.com/sightingphotos/9434.jpg) it has a large area of
white under its chin. I remember first being drawn to this when I saw my
bird i.e. a darker coloured bird with a white chin. The Pizzey and
Knight 'Field Guide to Australian Birds' (the guide I usually use as my
field reference and probably Australia's best current guide in terms
feature identification) shows an image of a Little Stint with a white
chin and a Red-necked Stint without a white chin. However, as it's been
pointed out, significant white areas on the chin are not uncommon in
partial breeding plumaged Red-necked Stint. Yet this is not often shown
in field guides - they usually show a non-breeding plumaged bird and a
full breeding plumaged bird. If you have a look at the images in Pizzey
and Knight and the photograph of the bird in question, to me the white
chin suggested a Little Stint. The following web site looks at the
features of the two birds and shows a white chin / neck in the little
Stint while the Red-necked Stint has a white around the base of the
bill: see http://www.birdinfo.com/stint.html.

In terms of the chestnut colour, I think the bird is the photograph
seems to be in a sightly more advanced state of moult to the bird that I
saw, although this could easily have been something to do with the dull
light at the time, and the date of the sighting.

When it come to the colour in the orange-rufous coloured wing feathers,
because I saw a white-chin and darker bird I was convinced that it had
"rufous coloured wing feathers including outer wing feathers". However
in the image they're actually white. White edges to tertials are in fact
a diagnostic of a Little Stint. This will be the first place I'll look
next time. I won't be making that mistake again.

In term of the WHITE mantle V, if I look hard enough at the bird in the
photo on Birdline I think I can see it! I'm sure it's there? Compare the
back of the Birdline bird with image of the birds at
http://www.birdinfo.com/stint.html.

Now lets not go into the bill shape, structure of the head and body,
legs and feet, and of course the voice. Peep.

Little Stint can be one of the most difficult birds to identify. If you
search the web you'll find literally hundreds of examples of Little
Stint and other "peeps" (a generic word synonymous with tiny shorebirds)
being analysed for identification. I've seen it written that Red-necked
Stint and Little Stint out of breeding plumage are impossible to
distinguish, even in the hand! I can't think of any other species where
this would be the case. I remember reading about an overseas report of a
potential Little Stint. One observer, to justify his credentials for
identifying the bird, states that he's "personally ringed thousands of
Little Stint!". The bird was eventually found to be a Red-necked Stint.
So Little Stint can be tricky little gadflies, and identification can be
a major challenge. With experience and careful analysis - and a
photograph helps - things seem to become clear. Hope this all makes
sense.

Cheers,

Tim Dolby



-----Original Message-----
From: 
 On Behalf Of Peter Shute
Sent: Wednesday, 17 June 2009 2:35 PM
To: Birding-aus (E-mail)
Subject: Red-necked Stint / Little Stint,
WesternTreatment Plant (Vic)

Tim, your birdline of 24/5/09 for Little Stint says "The Little Stint
was distinctively more chestnut in colour, with orange-rufous coloured
wing feathers including outer wing feathers, and white V line around the
back", which contradicts point 5, and possibly 3, if it wasn't a Little
Stint.  And Steve Davidson's report of 6/6 that mentions "strong
chestnut edges to the tertials", which contradicts 3.

Does this mean we'd need to identify all the features below to be sure
we're not looking at a Little Stint?

Peter Shute

Tim Dolby wrote on Wednesday, 17 June 2009 10:01 AM:

> Hi all,
>
> There have been a couple darker coloured / breeding plumage stints at
> the Spit at the Western Treatment Plant, Victoria. (One birds has an
> injured leg.) After careful analysis it's been concluded that both
> birds are Red-necked Stint, not Little Stint. One bird in particular
> has stood out because it is a brightly coloured bird (for a
> photograph see Birdline Victoria at
> http://www.eremaea.com/BirdlineRecentSightings.aspx?Birdline=1). This
> is because it is an adult Red-necked Stint that has not migrated,
> while nearly all the companion birds are first-year Red-necked Stint
> whch lack significant breeding plumage. Thanks Danny Rogers for his
> expertise in this area and careful analysis. The diagnostic
> Red-necked Stint features are:
>
> 1. LOTS of red on the face and throat. It does have a white chin, but
> this isn't unusual in breeding plumage RNS. Little Stint has a much
> bigger white area on the throat.
> 2. BAND of dark speckling below the red of the throat and upper
> breast. Little Stint lack this, they have dark streaking within the
> buffy rufous of their upper breast.
> 3. WHITE edges to tertials - Little Stint usually have very broad
> rufous outer edges to most or all of their tertials.
> 4. SIMPLE white supercilium - Little Stint adults usually (not
> always) show a split supercilium.
> 5. NO WHITE mantle V - usually present in breeding plumage Little
> Stint.
> 6. GENERAL long-bodied, short-legged appearance - Little Stints are
> slightly longer-legged and shorter-bodied, though it would be brave
> to ID them on that alone.
>
> Unless another Little Stint turns up I'd suggest that previous
> reports are erroneous.
>
> On a lighter side this means that I'm now one bird down in terms of
> my 2009 Victorian list, currently sittin at 311 for the year. These
> things happen, c'est la vie. I might have to chase the Brown
> Honeyeater in Kamarooka again, again. See
> http://tim-dolby.blogspot.com/  Once again thanks Danny Rogers for
> his assistance.
>
> Cheers,
>
> Tim Dolby



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