>
> one didn't realise pipits can be so confusing
Really? I thought that's the one lesson everyone learns again and again
about pipits. There's even a poem about it:
It's a pity that the Pipits have
No diagnostic features
Specifically they are the least
Distinctive of God's creatures
For naming any one you need
Five measurements, together
With a drawing of the wing tip
And the length of every feather.
Count the spots on breast and back,
Be sure of which the sex is;
Make a picture of the pattern
Of the one-but-outer rectrix.
Pay extravagant attention to
The hind claw's conformation;
Note 'weak and long', or 'curved and strong'
(Or 'snapped in preservation').
And when you've marshalled all the facts,
No matter what their sense is,
If the bird was caught in Europe
It is, ten to one, pratensis.
B. P. Hall, 1961
I've attached three photographs from Amitava that I thought were not
Paddyfield. (Note they may not be all the photographs he's posted of
these birds; nor does it seem like they're all of the same bird.)
> something which is further compounded by different guide books.one
> says paddy field pipits have dark lores while another says pale.
And both books are both correct and wrong at the same time. Field guides
simply do not have the space to discuss identification of pipits in more
than superficial detail. When you write a species account in a book, you
have to decide what to leave out. For everything you put in, someone can
find a counterexample. That's just how it is (and not only with pipits).
The "truth" is that you have to look at the lores of pipits as a
spectrum, with Tawny on the dark end, and Richard's and Blyth's on the
pale end, with Paddyfield somewhere in between, with mostly pale lores
in some places, and distinctly darker lores in some other places. Plus
the way the lores look can be affected at any time by angle and moult
(so yes, Tawny can have pale lores too).
Furthermore, this is true of more features than just the lores. This
means that you can't approach identifying pipits by checking boxes on
a feature list. It'll work sometimes, lead you astray at other times,
and you'll never be sure which times are which.
> >1. No dark streaking on back as expected
You're right, Blyth's usually has darker (black) streaks on the back and
mantle, but at the same time, the pattern seen in the last two photos is
very unlike typical Paddyfield. For one thing, Paddyfield doesn't show
streaks down the entire length of the back, they're usually short and
obscure. And even if there are any longer dark streaks, the pale streaks
in between are usually not as contrasting as this, they're just vaguely
grey. Actually the streaking pattern on these birds most closely matches
Richard's (which is somewhere between Paddyfield and Blyth's on the
streaking spectrum), but the bird doesn't otherwise look as robust
as you might expect Richard's to look.
(None of the above applies to the juvenile plumage, where the strange
black-centred scaly feathers on the upperparts can line up to look like
heavy streaks, albeit without pale streaks in between. But that's not
relevant here, as this is not the juvenile plumage of any of the four
large pipits.)
> >2.Overall smaller in size
I didn't pick up any size cues from the photographs, other than the very
short tail (which is most suggestive of Paddyfield).
> >3.Very pale bill(expected dark in Blyth's)
Blyth's usually have lower mandibles with pale pinkish bases (very like
the colour that Tawny shows on more of the beak). Paddyfield usually has
a darker beak, and even when part of the lower mandible is paler, it's
often a more yellowish or orangish colour.
(Again, note that I am not saying "Paddyfield can be distinguished from
Blyth's by looking at the orangeness of the base of the lower mandible".
That kind of reduction doesn't work. "Paddyfield has a darker beak on
average than Blyth's" is about all you can get away with.)
> >4.No squarish centres to median coverts
Note that it's only the centres of the _central_ median coverts in the
adult plumage that you can safely compare (the shapes of the others is
more variable, esp. in richardi and rufulus). In these photos, those are
simply not visible, and so the feature can't be used to draw any sort of
conclusion.
> >5.Breast not much streaked(though not well visible)
You cannot expect Blyth's to have a consistently more heavily-streaked
breast than Paddyfield. In my experience, a curtain of fine pin-streaks
is quite normal for Blyth's, and Paddyfield often has heavier streaks.
> so abhijit have u got yr specs back to look closely again at these
> pipits
I get the new pair tomorrow evening. More updates after.
-- ams
--
You received this message because you are subscribed to the Google Groups "delhibirdpix" group.
To post to this group, send email to delhibirdpix@googlegroups.com.
To unsubscribe from this group, send email to delhibirdpix+unsubscribe@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/delhibirdpix?hl=en.
No comments:
Post a Comment