I assumed that Harvey's maxim that: “if there’s any doubt, then it’s a Lesser”,
was based on appearance & not probability in numbers? i.e. if it's a Greater,
it will be obvious.
For me it's the reverse, i.e. when looking at Sand Plovers (not photos) "'if in
doubt, then it's probably a Greater". This is on based on the fact that for
me, whenever I've had some doubt, after taking a bunch of photos, I've almost
always concluded it's a Greater.
BTW, in Ballina (far northern NSW), we get very low numbers of both Greater &
Lesser, but generally Greater out-number Lesser by about 4-1
Cheers,
Steve
-----Original Message-----
From: Birding-Aus On Behalf Of
Chris Sanderson
Sent: Wednesday, 4 February 2015 3:51 PM
To: Neil Shelley
Cc: Birding-Aus
Subject: Re: [Birding-Aus] Sand Plovers at Lake Wollumboola
Also Harvey that rule of thumb about "assume it's a lesser" only works for the
east coast of Australia. In Broome the lesser is much fewer in numbers and the
greater's dominate. Worth getting a feel for the relative bill length and
taking a minute to be thankful we don't have to guess leg lengths like in some
parts of the world.
Thanks Neil for that data it confirms my field experience and puts it into a
pretty understandable format!
Cheers,
Chris
On Sun, Feb 1, 2015 at 11:03 AM, Neil Shelley <> wrote:
> Hervey,
>
> Here are some summarised measurement data that was published in Stilt
> some years ago (I can provide the exact references if anyone needs them):
>
> - *Lesser Sand Plover*
> - Bill 16.9mm
> - Head 28.8mm
> - Bill/Head ratio 0.59
> - *Greater Sand Plover*
> - Bill 23.8mm
> - Head 30.8mm
> - Bill/Head ratio 0.77
>
> As you can see from the above, the Lesser Sand Plover has the shorter
> bill and the species have similar size heads. This leads to the
> overall impression that the Lesser Sand Plover's bill is ~½ the size
> of its head & the Greater Sand Plover's bill is ~¾.
>
> I hope this helps.
>
> *Neil Shelley*
>
> On 31 January 2015 at 11:43, Harvey Perkins <> wrote:
>
> > Well, after quite a bit of email traffic on Birding-aus over the
> > past couple of days, both public and private, the consensus is very
> > clearly
> that
> > the two birds I photographed at Lake Wollumboola are both Lesser
> > Sand Plovers. Bird #1 came “close” but was still universally
> > considered a Lesser. I asked some of the respondents for additional
> > tips as to why and can summarise as follows.
> >
> >
> >
> > To a large degree it is the “jizz” of the bird, particularly around
> > the overall proportions and shape of the head, legs and body, but
> > especially, the bill length seems to be key. None of this was new to
> > me, and these
> are
> > all features identified in the field guides to look for, but clearly
> > I
> just
> > don’t have the experience with these birds to ‘get it’ just yet.
> >
> >
> >
> > Some of the comments included:
> >
> >
> >
> > *“I find it's immediately a 'jizz' thing. Greaters just look so
> long-legged
> > they look awkward. The tibia is very long which elevates the body
> > way up off the knees. They look as if they're about to topple
> > forwards. The bill is important too. A Greater has a bill that is
> > much longer and thicker
> than
> > a Lesser and if stuck onto the side of the head of the bird (ouch)
> > would probably reach behind the eye.”*
> >
> >
> >
> > *“The bills of your birds look very much on the short side for
> > Greater,
> and
> > also relatively bulbous- and blunt-tipped which is better for Lesser.
> > Similarly, the overall shape and proportions are much 'nicer',
> > whereas Greaters tend to look more gangly with oversized heads and
> > bills. That said, there is significant variation in both species,
> > and birds with more intermediate features can be extremely
> > challenging to assign to species”*
> >
> >
> >
> > So it seems there will be some individuals, at either end of a
> > scale,
> that
> > will fit neatly into clear-cut ‘identifiability’ as one or the
> > other. The photo on my blog of the Lesser Sand Plover from Northwest
> > Island is one
> of
> > these. But I suspect a large number of birds, if not the majority,
> > will fall instead within the range of ‘confusability’ for a large
> > number, if
> not
> > the majority, of people. I take some comfort from the statement in
> > the *NPIAW – The Shorebirds of Australia* which states that,
> > “Identification is therefore far from easy, even for experts,
> > especially as individual birds may be at different stages of their
> > moult”.
> >
> >
> >
> > It’s probably worth keeping in mind the maxim that: “if there’s any
> doubt,
> > then it’s a Lesser”.
> >
> >
> >
> > So, As foreshadowed in my initial email to Birding-aus, I have ended
> > up slightly embarrassed (and my credibility as a wader watcher and
> birdwatcher
> > more generally must be well and truly shot!), but it has been worth
> > it
> for
> > the feedback it triggered and the better understanding I now have.
> > Thanks to all.
> >
> >
> > I’ve updated my blog post with this text as a Postscript.
> >
> > Cheers,
> >
> > Harvey
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