[Tweeters] "Purple-throated" Nutcrackers

Gudalewicz Dasha dasha at gudalewicz.com
Sat Sep 24 11:07:00 PDT 2016


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:
https://ololaiki.smugmug.com/Animals/Birds/Corvids/Clarks-Nutcracker-2/

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:
https://leerentz.wordpress.com/2010/10/30/banff-national-park-friendly-relations-between-clarks-nutcracker-and-whitebark-pine/

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 <https://birdsna.org/Species-Account/bna/species/clanut/references#REF7261> , Hutchins and Lanner 1982 <https://birdsna.org/Species-Account/bna/species/clanut/references#REF7244> , Christensen et al. 1991 <https://birdsna.org/Species-Account/bna/species/clanut/references#REF41626> ). 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
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