GOLDEN-CROWNED SPARROW 1357 



In his report on the Atlin region of British Columbia, Swarth 

 (1926) states that this plumage in the golden-crown 



* * * is generally similar to the same stage in the three species of white- 

 crowned sparrows. Coronata lacks the decided head markings that are seen in 

 the juvenal white-crowns and it has a suggestion of yellowish upon the forehead. 

 Compared with the grayish leucophrys, young coronata is generally darker colored 

 and the ventral streaks are darker, heavier, and more extensive. Compared with 

 gambelii, young coronata is generally browner. Young coronata and young nuttalli 

 are closely similar in body coloration, but the former is slightly darker colored as 

 a rule. Coronata has a heavier bill than the white-crowned sparrows, and this 

 character is apparent in the young birds. 



The accompanying illustration (pi. 4) was made [by Major Allan Brooks] from 

 studies of the freshly killed bird. The yellowish tinge to the lower parts, as there 

 shown, is an evanescent color that soon disappears from the study skin. * * * 



On July 18 young were taken in juvenal plumage throughout and with full- 

 grown rectrices. Others molting into first winter plumage were collected July 

 27 and August 5. One young bird still mostly in juvenal plumage was taken 

 August 24. 



Robert Ridgway (1901) describes the young in first winter plumage 

 as "Similar to adult female, but without any lateral black stripe on 

 pileum or well-defined median stripe, the whole forehead and anterior 

 portion of crown yellowish olive, more or less flecked with dusky 

 (sometimes with more or less indication of a black lateral stripe), 

 the posterior portion of the pileum light grayish olive-brown, streaked 

 with dusky." This dress is apparently assumed by a partial molt 

 of the juvenal plumage before the birds leave the nesting ground. 



The adult breeding plumage with its prominent yellow and grey 

 median crown stripe is attained by a spring molt that starts in late 

 winter and involves most of the head and body feathers, the tertiaries, 

 the secondary coverts, and the central pair of tail feathers. In his 

 excellent description of the process J. E. Law (1929b) notes: 



In individuals, the progress of molt seems to vary. One tract or another may 

 be relatively further along in different birds, * * *. The time of molt is more 

 erratic. On any day, in March and April, one may take birds of the same species 

 which appear to be a month apart in progress of molt. Individuals with feathers 

 still growing may be caught even in early May when all but a few members of 

 the flocks of Z. coronata and Z. gambelii have departed from southern California, 

 but most of the last to go have completed their molt before they depart. * * * 



I have not detected regular spring molt in any of the following tract series: 

 Primary and secondary remiges, alula, upper and under primary coverts, outer 

 five pairs of rectrices, dorsal saddle, and rump. It is significant that when wings 

 and tail are folded, as they are much of the time that the bird is not flying, all of 

 the above series are covered. The tertiaries cover the primaries and secondaries, 

 the greater secondary coverts cover the alula and primary coverts, the under 

 secondary coverts cover the under primary coverts, the wing covers the dorsal 

 saddle and rump, and the deck [central] rectrices cover the remaining pairs of 

 tail feathers. It appears, therefore, that only the tracts of the body directly 

 exposed to abrasion and sunlight are renewed in the spring molt. * * * 



