[Tweeters] "Purple-throated" Nutcrackers
lguy_Mcw at yahoo.com
Sat Sep 24 17:24:59 PDT 2016
From Teresa Lorenz, a couple of years ago, when I also spotted some Nutcrackers with purple faces ...
"Red anthocyanins (pigments) in unripe whitebark pine
cones stain the face and breast feathers of nutcrackers foraging on unripe
Lguy_mcw at yahoo
On Sep 24, 2016, at 11:07 AM, Gudalewicz Dasha <dasha at gudalewicz.com> wrote:
> Hello Tweets,
> Two weeks ago at Sunrise, Mount Rainier, I saw and photographed a nutcracker with throat stained pinkish/purplish. That reminded me that three years ago, in July, 2013, I saw two birds with similar stains, also at Sunrise.
> First six images here:
> That made me curious. But I couldn’t find anywhere what causes such staining.
> And the only other photos I found online were made in Banff NP:
> I asked Dennis Paulson if he ever saw something like that and he did! At Sunrise in October 1974 he photographed what he called “Purple-throated Fruitcrow” :)
> Dennis and I think that the most reasonable theory is that immature Whitebark Pine cones produce some kind of purplish stain.
> From Clark’s Nutcracker profile on BNA Online:
> “Beginning mid- to late Jul, harvests unripe pine seeds ( Tomback 1978a , Hutchins and Lanner 1982 , Christensen et al. 1991 ). Removes seeds from closed whitebark, piñon, limber, Jeffrey, and ponderosa pine cones…”
> But at the same time:
> “Whitebark pine seeds stored as early as 15 Aug in Rocky Mtns. and 25 Aug in Sierra Nevada.”
> Does anybody know when nutcrackers start collecting Whitebark seeds at Rainier? (as my first sighting was in July)
> Have any of you encountered (and probably photographed) stained nutcrackers?
> Or have you handled unripe Whitebark cones and can confirm that they stain?
> If you’re planning on hiking Rainier (or any other place where Whitebark Pines grow) would you be willing to collect a cone (if it is in the hand’s reach!) and check if it stains?
> Thank you!
> And happy birding,
> Dasha Gudalewicz,
> Sammamish, WA
> Tweeters mailing list
> Tweeters at u.washington.edu
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