Friday, October 26, 2012

"Fri-D" - of Races and Falling Down Mountains

 [Male American Three-toed Woodpecker, Rocky Mountain National Park, October 25, 2012. Note the essentially unstriped back, characteristic of the Rocky Mountain race of this species. Click to enlarge photos.]

At least I got a new pair of boots out of it.

Who would have thought an American Three-toed Woodpecker, a male for heaven's sake, would alight on a pine downhill of me, so as to be almost eye level. Let me explain: this bird is a pearl of great price almost anywhere it is found, often shifting old reliable locations to find new, freshly dead trees each year. I'd taken pains to pump the park naturalists for info on current locations for the bird, and here one dropped in front of me utterly unexpected while I hiked on a snowy afternoon above Little Horseshoe Park in Rocky Mountain National Park. All I needed to do was creep upslope of the trail a step or two to find an opening between branches, and a full-frame photo was mine. A snowy, slippery slope. I creeped, got the shot off, and promptly fell on my back, centering a rock with my spine in the process. Was it worth it? Hek, yeah, and on the way back to the hotel I picked up a primo pair of Lowa hiking boots (at a premium price, of course), dropping the sole-worn Timberlands in a dumpster on the way out.

Right. Fri-D. So one of the cool things about the Sibley guide, if you read the front matter, is the way he separates races geographically, and by extension, the way that explains variation because of isolation by geography. Thus, American Three-toed Woodpeckers (and Hairy Woodpeckers and White-breasted Nuthatches and others) of the mountain west look slightly different than races found elsewhere. See the pics and captions for details.

[White-breasted Nuthatch, Rocky Mountain National Park. If you are from the east it should look funny to you. In comparison with the eastern race, the back is too dark, flanks too dark and too rich with rust, and the black crown so narrow that it is better called a stripe than a cap.]

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