THE WESTERN YELLOW-THROAT. = 
along the shaded banks of streams, but may possibly be found along more 
open margins, consorting with Pipits, with which it shares a restless habit of 
jetting, or curtseying, whimsically. 
No. 81. 
WESTERN YELLOW-THROAT. 
A. O. U. No. 681 a. Geothlypis trichas occidentalis Brewster. 
Description.—4 dult male in spring and summer: Above grayish olive-green, 
brighter (less gray) on upper tail-coverts and tail, inclining to brownish on 
crown and hindneck; an obliquely descending facial mask of black involving 
forehead, lores, space about eyes, cheeks and (more narrowly) sides of neck; 
along the posterior margin of this mask a narrow sharply contrasting area of 
clear ash or white; chin, throat and breast rich yellow (inclining to gamboge) ; 
sides of breast and sides heavily shaded with olive-gray and breast more or less 
washed with same; lower breast and below between yellow and palest olive-gray ; 
under tail-coverts and bend of wing clear yellow. Adult male im autumn: 
Occiput more decidedly brown; upperparts clearer olive-green. Young male in 
first autumn: Mask of adult merely indicated by black underlying sooty-brown on 
sides of head; coloration of underparts duller. Adult female in spring: Like adult 
male but without black mask and ashy edging; crown and sides of head olive 
gray; forehead tinged with brown; region above and about eye notably paler; 
coloration of underparts duller and paler, sometimes clearly yellow on under 
tail-coverts alone. Young female in first autumn: Similar to adult but under- 
parts still duller and dingier, breast and sides heavily washed with brownish 
olive. Length of adult about 5.00 (127); wing 2.26 (57.5); tail 2.19 (55.8); 
bill .44 (11.3); tarsus .83 (21). 
Recognition Marks.—Warbler size; black mask and white fillet of male 
distinctive. ‘The female is a much more difficult bird to recognize—perhaps best 
known by peculiar sordid olive-brownish-vellow shade of underparts. The pale 
orbital area also assists, but one must live with these birds to know them 
infallibly. 
Nesting.—Nest: of coarse grasses lined with fine grass and horse-hair; 
placed 1-2 feet high in tussock of grass or rank herbage, usually near water; 
outside 41% wide by 3% deep, inside 214 by 1%. Eggs: 4 or 5, dotted and 
spotted or, rarely, streaked with blackish and lavender. Av. Size, .70x.56 
(17.8x 14.2). Season: May 20-June 10; one brood. 
General Range.—Western United States and British Columbia, except 
Pacific coast district, east to western portions of the Great Plains; breeding 
southward into Mexico and northern Lower California; in winter south to Cape 
St. Lucas and western Mexico. 
Range in Washington.—Summer resident east of the Cascade Mountains ; 
found chiefly in rye-grass districts and in vicinity of water. 
