The Bullock Oriole 



the species is slowly extending its range. Its normal choice of altitude, 

 however, from 4000 to 6000, is rather narrowly represented in the Upper 

 Sonoran zone of California, and its total population does not begin to 

 compare with either /. bullocki or /. cucullatas nelsoni. 



No. 17 



Bullock's Oriole 



A. O. U. No. 508. Icterus bullocki (Swainson). 



Description. — Adult male: Black, white, and orange; bill, lore, a line through 

 eye, and throat (narrowly) jet black; pileum, back, scapulars, lesser wing-coverts, 

 primary coverts, and tertials, chiefly black, or with a little yellowish skirting; remiges 

 black edged with white; middle and greater coverts, continuous with edging of tertials 

 and secondaries, white, forming a large patch; tail chiefly cadmium-yellow, but central 

 pair of rectrices black on exposed area, and remaining pairs tipped with blackish; 

 remaining plumage, including supraloral areas continuous with superciliaries, orange 

 (cadmium-orange in oldest examples), most intense on sides of throat and chest, shading 

 on lower breast to cadmium-yellow posteriorly; rump washed with olivaceous. In 

 younger adults the orange is less intense, and the tail is more extensively black. Bill 

 black above, bluish below; feet and legs (drying) dusky horn color. Adult female: 

 Above drab-gray, clearest on rump and upper tail-coverts; washed with yellow on head; 

 wings fuscous with whitish edging; pattern of white in coverts of male retained, but 

 much reduced in area; tail nearly uniform dusky orange (aniline yellow to old gold); 

 sides of throat and chest wax-yellow (with irruptions of orange in older birds); chin 

 and throat (narrowly) and remaining underparts sordid white or pale creamy buff; 

 the under tail-coverts usually (but not always) tinged with yellow. Immature male: 

 Like adult female; yellows of head and throat stronger. Young male in first spring: 

 Like adult female, but sides of head, throat, and breast aniline yellow; lores, chin, and 

 throat narrowly black. Birds breed in this plumage, and it is uncertain whether or not 

 it may be carried into the second year. Length of adult male about 210 (8.25); wing 

 100 (3-94); tail 79 (3.1 1); bill 18.5 (.73) tarsus 25 (.98). Female somewhat smaller. 



Recognition Marks. — Towhee size; black, white, and orange coloration; top of 

 head black, and under side of tail yellow, as contrasted with the Arizona Hooded Oriole. 

 Females and young extensively whitish below. Note slender, blackish bill of female, 

 as contrasted with heavy, light-colored bill of Western Tanager {Piranga ludoviciana) ; 

 wing-bars white; underparts with contrasting yellow and whitish, where the Tanager 

 is uniform greenish yellow. 



Nesting. — Nest: A pendent pouch of elaborately interwoven grasses, vegetable 

 fibers, string, or horsehair, either uniform or variously composed; 5 to 9 inches in depth, 

 and lashed by brim, or suspended by lengthened filaments, to branches of deciduous 

 trees, usually at moderate heights. Eggs: Usually 5; elongate ovate; grayish white or 

 bluish white as to ground, or, rarely, tinged with claret, boldly and intricately scrawled 

 with pen lines, fine or broad, of purplish black. The pattern tends to confluence in a 

 coronal wreath, or cloud cap, and appears as though traced continuously through many 



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