298 BLACKBIRDS, ORIOLES, ETC. 



Nest. Long, bag-shaped, hung from the rim, usually to slender 

 branches 8 to 50 feet from the ground; woven of hemp, horsehair, or 

 twine, lined largely with hair and grass. Eggs : 4 to 6, grayish, irregu- 

 larly streaked and blotched, most heavily about the larger end, with black, 

 brown, and lavender. 



Food. Mainly noxious insects and larvae, including click beetles, 

 locusts, grasshoppers, weevils, ants, plant lice, and caterpillars. 



The Baltimore oriole goes as far west as Colorado and Montana, 

 but bullocki, its western congener, is more abundant west of the 

 Plains. 



508. Icterus bullocki (Swains.). BULLOCK ORIOLE. 



Adult male in summer. Under parts, sides of head and neck, and su- 

 perciliary orange ; narrow throat patch, crown, back of neck, back, and 



stripe through eye, black ; 

 wings with conspicuous white 

 patch and edgings ; tail with 

 middle feathers black, chan- 

 ging to almost pure yellow on 

 outer feathers. Adult male 

 in winter : like summer male, 

 but scapulars and interscapu- 

 lars edged with gray, feath- 

 ers of rump and upper tail 

 coverts tipped with gray, of 

 under parts edged with whit- 

 Fig. 365. ish. Adult female : under 

 parts lemon yellow, fading 



to gray on belly ; throat usually with more or less of black ; upper parts 

 olivaceous, fading to brownish and sometimes streaked with black on 

 back, but brightening to olive yellow or deeper on rump and tail ; wings 

 with white bands. Immature male in second year : similar to adult female, 

 but lores and median line of throat black. Young in first plumage : 

 similar to female, but colors duller, washed more or less with buffy, with no 

 trace of black on the throat, and yellow sometimes almost wanting. Male : 

 length (skins) 6.75-7.60, wing 3.82-4.03, tail 2.98-3.22, bill .65-.81. Fe- 

 male: length (skins) 6.60-7.50, wing 3.52-3.87, tail 2.73-3.12, bill .67-.7S. 

 Distribution. Breeds in Upper and Lower Sonoran zones of western 

 North America from southern parts of British Columbia, Alberta, and 

 Assiniboia, south to western Texas and Lower California ; and from Da- 

 kota and Texas to the Pacific ; migrates to the valley of Mexico and 

 Puebla. 



Nest. Hung by rim and fastened to sides of a branch 6 to 40 feet from 

 the ground, often in bunches of mistletoe in cotton woods, poplars, and 

 mesquites, woven of horsehair or vegetable fibers and inner bark, lined 

 with horsehair, down, and wool. Eggs : 3 to 6, grayish or bluish white or 

 pale buffy, marked with irregular hair lines, mainly around the larger 

 end. 



Food. Principally injurious insects and larvae, with a few wild berries. 



In southern California, where the Arizona hooded and Bullock 

 orioles occur together, the light, yellow-headed nelsoni usually comes 

 north later and lives largely in the chaparral, while the dark orange 



