The Oregon Juncoes 



the ones which retire to our borders; while the wintering birds may have 

 descended from the Olympics or from Mount Rainier. 



No. 51b Sierra Junco 



A. O. U. No. 567c. Junco oreganus thurberi Anthony. 



Synonyms. — Thurber's Junco. California Snow-bird. 



Description. — Adult male: Similar to J. 0. couesi, but head, neck, and chest, 

 blacker; i.e., of recovered intensity, practically as black as J. 0. oreganus; sides much 

 paler, avellaneous to vinaceous-buff. Adult females: In mature examples closelv 

 approximating the colors of adult males; black of foreparts only a shade less intense; 

 back a little more rufescent and a shade lighter. Young birds: Like those of J. 0. 

 oreganus but lighter and grayer above, and never yellowish buffy below, palest pinkish 

 buff instead. Length of adult male (after Ridgway) : 135-151 (5.32-5.95); wing 78 

 (3.07); tail 65.3 (2.57); bill 10.7 (.42); tarsus 20 (.79). Females; wing 72.9 (2.87); tail 

 62.2 (2.45); bill 10.7 (.42); tarsus 20.3 (.80). 



Recognition Marks. — Sparrow size; head, neck, and chest black; convex out- 

 line of chest contrasting with white of breast and light pinkish of sides; the commonest 

 form. 



Nesting. — Nest: On the ground, sunk flush, or not; often deeply recessed on 

 side hill, or else under protection of low shrubbery; a sturdy cup with walls an inch or 

 more in thickness, wrought externally of mosses, weed-stems, and dried grasses, and 

 lined with fine, light-colored grasses, or horsehair where obtainable. Eggs: 3 to 5; 

 ground-color white tinged with pinkish, greenish, or bluish, speckled or spotted, broadly 

 or narrowly, rarely mottled or clouded with reddish brown or vinaceous. Av. size. 

 19.8 x 15.2 (.78 x .60). Season: May-July; two broods. 



Range of J. 0. thurberi. — Chiefly the mountains of California, but breeds from 

 an undetermined area in Oregon south to the Laguna Hansen Mountains of Lower 

 California; in winter found at lower levels, and casually east to Arizona. 



Distribution in California. — A summer resident of Transition and Boreal 

 zones throughout the State, save in the Monterey section, where replaced by J. 0. 

 pinosus. An irregular breeder at intermediate levels (e. g. Santa Margarita — Swarth); 

 and a casual breeder at lower levels (Stanford University — Snyder; Berkeley — Wythe). 

 In winter found at all lower levels including the deserts (sparingly) and the Channel 

 Islands. 



Authorities. — Newberry (Struthus oregonus), Rep. Pac. R. R. Surv., vol. iv., 

 1857, p. 88. part (n. California in summer); Anthony, Zoe, vol. i, October, 1890, p. 238 

 (Wilson's Peak; orig. desc); Kaeding, Bull. Cooper Orn. Club, vol. i., 1899, p. 80 

 (Calif.; distr., habits, crit.) ;Grinnell, Univ. Calif. Pub. Zool., vol. v., 1908, p. 95 (habits, 

 desc. nests and eggs, etc.); Beat, U. S. Dept. Agric, Biol. Surv. Bull., no. 34, 1910, p. 82 

 (food); Dwight, Bull. Am. Mus. Nat. Hist., vol. xxxviii., 1918, p. 291, col. pi. (distr., 

 variation, crit.). 



ONE'S FIRST encounter with Junco in the Southland is likely to 

 take place on some little oak-sprinkled ridge, the coolest of that section. 

 First one bird, then another, will quit the ground, most unexpectedly to 

 you, and take refuge in a live oak tree. It's a game of hide-and-seek 

 henceforth with you for "it," unless you resolutely sit down and efface 



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