The Russet-backed Thrushes 
Description. — Adults: Above olive-brown (bright sepia—not nearly so red as the 
name “russet” would indicate), substantially uniform; a conspicuous orbital ring of 
pale buff; sides of head warm buffy, mingled or streaked with olive-brown; chin, throat, 
and chest buff (or lightening to buffy white toward chin); sides of throat and entire 
chest with triangular marks of deep olive-brown, smaller and narrower on throat, 
larger and broader (sector-shaped) posteriorly; breast, especially on sides, transversely 
spotted with light brown; sides and flanks heavily marked with brownish; remaining 
underparts white. Bill blackish, paling basally on mandible; feet and legs brown; 
iris brown. Winter specimens are brighter, more deeply tinged with buff before, and 
with under tail-coverts buffy. Young birds are more or less marked and streaked with 
buffy and tawny above on a rich sepia ground, and the markings of underparts are 
mostly transverse; underparts, save on middle of belly, heavily tinged with buffy. 
Length 165.1-190.5 (6.50-7.50); wing 97 (3.83); tail 73 (2.87); bill 13.7 (.54); tarsus 
28 (1.10). 
Recognition Marks. —Sparrow size; uniform olive-brown above; heavy spotting 
and buffy wash on chest; sides of head and eye-ring buffy; warm brown above, as 
compared with H. u. swainsoni. 
Nesting. — Nest: Of twigs, grasses, and macerated vegetation, or else chiefly of 
moss with inner matrix of dead leaves and leaf-skeletons, laid in wet; no special lining. 
Eggs: 4, rarely 5 (in these latitudes); light bluish green (glaucous green to pale niagara 
green, or else grayer), spotted rather uniformly but sparingly, sometimes diffusely, 
with reddish brown (walnut-brown to russet). Av. size (of southern specimens): 
22.4 x 16.5 (.88 x .65). Season: May-July; one brood. 
Range of Hylocichla ustulata. —North America; breeding chiefly north of the 
L'nited States, but also in the mountains and in the Pacific Coast States; wintering 
from southern Mexico, south to Brazil, Argentina, and Bolivia. 
Range of II. u. ustulata. —Breeds in the Pacific Coast district from Juneau, 
Alaska, south to San Diego. Winters from Vera Cruz and Guatemala south to northern 
South America, from British Guiana to Ecuador. 
Distribution in California. —Abundant and of general distribution during 
migrations. Common summer resident along timbered streams of Upper Sonoran and 
Transition zones west of the Sierran divide. Breeds south to Poway, in San Diego 
County. More sparingly distributed on the slopes of the Sierras and in the northern 
humid coastal belt. 
Authorities.—Heermann ( Turdus solitarius), Jour. Acad. Nat. Sci. Phila., 
ser. 2, ii., 1853, p. 265 (Calif.); Ridgway, Proc. Acad. Nat. Sci. Phila., 1869, p. 129 
(relationships of ustulatus discovered through character of eggs); Belding, Proc. Calif. 
Acad. Sci., ser. 2, ii., 1889, p. 57 (range, migr., song, nesting); Oberholser, Auk, vol. xvi., 
1899, p. 23 (syst.; orig. desc. Hylocichla ustulata oedica, type locality Santa Barbara); 
Beal, U. S. Dept. Agric., Biol. Surv. Bull., no. 30, 1907, p. 86 (food); /. Mailliard, 
Condor, vol. xx., 1918, p. 192 (song). 
THE RUSSET-BACKED THRUSH is the happy incarnation of the 
underforest, the authentic dryad of the P'arther West; for wherever shaded 
waters empty into the blue Pacific, the shifting browns of this bird’s 
upperparts melt and blend with the tints of fallen leaves, dun roots, and 
the shadows of tree-boles cast on the brown ashes of fallen comrades. Not 
content, either, with such protective guarantee, this gentle spirit clings to 
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