Subject: [Tweeters] more about bunting ID
Date: Jan 19 09:46:27 2005
From: Dennis Paulson - nettasmith at comcast.net


Hello, tweeters.

Delete if not interested in the ongoing discussion of bunting
identification.

I spent quite a bit of time yesterday reading Peter Pyle's account of
Snow and McKay's Buntings in the 2nd edition of his book on passerine
identification. I also looked at the series of Snow Buntings in the
Slater Museum.

Pyle is difficult reading, as you keep having to go back under each age
and sex to try to winnow out the characters by which you distinguish
them. Here is his statement about distinguishing plumages of Snow
Buntings: "When combined with measurements, all birds should be
reliably sexed (especially by underwing and P9 contrasts) and most
birds should be reliably aged." Well, we don't have measurements on
photographed birds, and we can't see their underwing or the pattern of
their outermost primary feather, so we're lost. I looked at 7 males and
7 females collected during the winter, and there was absolutely no way
to sex or age them except by characteristics that you can't see on a
perched bird (or a study skin without doing some prying and poking).

The only character he listed for age and sex distinction that could be
seen on a perched bird was the color of the outer greater coverts. In
adult males they are white, while in adult females and immatures of
both sexes they are blackish with white tips. The big white swatch
across the wing in the pale bunting I photographed at Harrison Hot
Springs would indicate it as a male, which I guess is why I so named it
in the first place. But that of course is if it was a Snow Bunting, and
it's obviously not a pure Snow Bunting.

So how do we distinguish ages and sexes in McKay's Bunting? Pyle says:

female - back feathers with large and distinct black centers
imm male - back feathers usually with small black centers
ad male - back feathers usually with small black centers or lacking
black entirely

No other criteria could be seen on a perched bird.

So if the HHS bird was a pure McKay's, it would perhaps be an immature
male.

How about distinguishing McKay's from Snow? Pyle lists a few characters:

Snow with back and rump brown to buff, McKay's with it mostly whitish
Snow with less white in wing and tail than McKay's

Of these criteria, you can only see the back, and by that criterion the
bird should be a McKay's.

Jay Withgott has written to Dan Gibson to ask him for more details
about why he considered the bird a hybrid.

That's all I know.

Dennis
-----
Dennis Paulson & Netta Smith
1724 NE 98 St.
Seattle, WA 98115
206-528-1382