Subject: Re: Mystery Stint (take two)
Date: Aug 29 13:42:35 1997
From: Mike Patterson - mpatters at orednet.org




This stint gives us all a really good opportunity to see how the
scientific method is supposed to work. Ruth saw a bird and formed
an hypothesis about its identity. She then provided others the
opportunity to test her hypothesis by providing photographs (if
she had been unable to get photos, sketches and fieldnotes could
have been submitted).

>From this, 3 alternative hypotheses have been suggested and we can
test them on the photos as well.

This bird has rather striking yellow/green legs. The 3 stints that
are *supposed* to have yellow legs are Temminck's Stint, Long-toed
Stint and Least Sandpiper. If the bird fails (because of other
characters) to meet the criteria for a yellow legged stint then we
must conclude that we are dealing with an aberration (however
minor).

Aberrations make things difficult, because one can dismiss contrary
opinions by invoking the aberrant hypothesis to any character.
I found myself doing this when I read the hypotheses conflicting
with my own this morning. And I'll be suggesting a variation on
the aberrant hypothesis before I'm finished here. Invoking the
aberrant hypothesis must be done with extreme caution.

I think we can test and discard the Long-toed Stint hypothesis
quantitatively by looking at photo #4. The middle toe should be as
long or longer than the tarsus. This is clearly not the case.
I believe that this and other plumage characters effectively
eliminates LTST. And I agree with Michael Price that plumage
characters eliminate Temminck's Stint, Red-necked Stint and
Least Sandpiper.

I'm guessing that the photos were taken with Kodak Kodachrome
film (which gives you a nice bright color, gives you the greens
of summer, makes it seem all the world is a sunny day, oh yeah).
Kodachrome tends to warm up the colors. This is my alternate
aberrant hypothesis. I agree that the colors do make this
look very semipalmated-like, but would suggest that this may be
an effect of the film choice.

I think the bird is too long-legged and long necked for Little
Stint (and I've seen 100's in Africa). I'm also not really
impressed with the plumage regarding Little Stint. It's just
not striking enough. I know this is a wishy-washy jizzy sort of
complaint, but it's mine and I'm sticking with it.

The general size, the long-leggedness, the bill with the blob at
the end all make me want to stay with Western Sandpiper, but I
can see Semipalmated Sandpiper as a possibility as well. But I
feel very confident in eliminating all Eurasian stints from the
list of possibilities.



--
********************************* I am but mad north-north-west;
* Mike Patterson, Astoria, OR * when the wind is southerly,
* mpatters at orednet.org * I know a hawk from a handsaw.
http://www.pacifier.com/~mpatters -ws