WHITE-WINGED JUNCO 1025 



could not fly, they moved along the ground at a surprisingly rapid 

 rate and attempted to clunb into brushpiles and shrubs." 



Plumages. — The scant natal down is slate-gray in color. The skin 

 of the newly-hatched bird is black. 



Richard Graber (1955), in a comparative study of immature plum- 

 ages of sparrows, describes the juvenal plumage as follows: "Fore- 

 head and crown gray, streaked profusely with black. Nape similar, 

 tinged with brown. Back brown-tinged gray, streaked with black. 

 Rump and upper tail coverts grayish, obscurely streaked with black. 

 Outer three rectrices largely white; others black, edged gray (fourth 

 from outside with white mark). Remiges black, primaries and sec- 

 ondaries edged light gray. Tertials edged with pinkish-buff, tipped 

 with buffy-white. Lesser coverts grayish, medians black, narrowly 

 white-tipped. Greaters edged with buif, ripped huffy white. Two 

 narrow wing bars. Lores gray, eye ring white. Auriculars gray. 

 Post auriculars white, sparsely spotted with dusky (cheek patch par- 

 tially outlining auriculars). Chin and throat grayish white (lateral 

 black streaks), obscurely flecked with dusky. Sides of chest gray. 

 Chest, sides, and flanks tinged with buff, streaked with black. Belly 

 white, crissum buffy white, both unmarked. Leg feathers gray and 

 white. Much like J. hyemalis, though clearly distinguishable." 



Robert Ridgway (1901) describes Junco aikeni as follows: 



Adult male. — Head, neck, chest, sides, flanks, and upper parts plain slate-gray, 

 darker (slate color) on the head; middle and greater wing-coverts usually tipped 

 with white, forming two distinct bands; three outermost tail-feathers wholly 

 white, the third sometimes with a little dusky, the fourth with more or less of 

 white * * * . 



Adult female. — Similar to adult male, but rather paler gray, the upper parts 

 (especially back) tinged more or less with light grayish brown, the wing-bands 

 usually less distinct, frequently obsolete, and the third tail-feather more often 

 with a little dusky * * * . 



Winter birds, especially young, are more or less tinged with light grayish 

 brown, especially on the back. In some adult males the tertials are edged with 

 white. 



Food. — No stomach analyses have yet been made. Insects appear 

 to constitute all the food of the nestlings, and are probably the chief 

 food of adults during the summer. In winter the white-wmg's diet 

 is primarily weed and grass seeds picked up from the ground. 



Behavior. — The white-winged junco is essentially a ground bird. 

 Nesting takes place primarily on the ground, and most feeding does 

 also. Trees are used for singing perches during the breeding season, 

 as resting places throughout the year, and probably as roosting sites 

 in winter. The most obvious behavior patterns can be observed in 

 fall and winter flocks. In one such flock 20 birds observed Oct. 4, 

 1956, were feeding in a gravel drive at 4,500 feet altitude. They 

 repeatedly flew down to the ground one at a time, but after feeding 



