SOUTHERN AMERICAN REDSTART 667 



and, hence, the identification of the sexes of the younger individuals is 

 more difficult. 



The natal plumage is hair-brown and is present as small tufts 

 located on the crown and various tracts of the dorsal part of the body. 



The Juvenal plumage is well established at the time the young leave 

 the nest and in the course of a few weeks is completed with all of the 

 feathers unsheathed. Jonathan Dwight, Jr. (1900) , has described the 

 Juvenal plumage as follows : "Above, including the sides of the head, 

 deep sepia-brown. Wings and tail deep olive-brown, the basal portion 

 of the primaries, secondaries and outer rectrices pale lemon-yellow, 

 the secondaries and tertiaries edged with dull olive-green, the coverts 

 with wood-brown paler at the tips. Below, pale primrose-yellow, 

 hair brown on the chin, throat and breast. Bill and feet dusky pinkish 

 buff darkening to brownish black when older." 



George A. Petrides (1943b) studied the plumage of a young redstart 

 which he kept in captivity after it had left the nest. He found that at 

 10 days of age the tail feathers began breaking out of their sheaths ; 

 at 13 days the yellow areas on the wings first appeared and by 20 days 

 the yellow patches of the tail became completely exposed. It was not 

 until the young were 26 days old that the yellow patches of the wings 

 were fully visible. 



When the bird was 22 days old the slate-gray juvenal plumage of 

 the occipital and dorsal tracts was being replaced in quantity by the 

 olive-green first winter plumage. The yellow underwing coverts also 

 began to appear at this time; previously the underwing areas had 

 been naked. The postjuvenal molt was thus begun before the juvenal 

 plumage was fully acquired. 



The first winter plumage involves changes in the body feathers and 

 wing coverts but not the rest of the wings or the tail. Dwight 

 (1900) describes this plumage as follows : 



Unlike the previous plumage. Above, the pileum, nape and sides of neck 

 mouse-gray, the back olive-green, often tinged with brownish orange, the upper 

 tail coverts clove-brown. The wing coverts become dull olive-green. Below, 

 dull white, ashy and pinkish buff suffusing the chin and throat, and orange- 

 ochraceous or deep chrome-yellow area on either side of the breast, the color 

 tinging the breast and sides. Orbital ring, white. 



First nuptial plumage acquired by a partial prenuptial moult, which involves 

 chiefly the head and throat, where a few black feathers in patches are acquired. 

 A few may be found scattered sparingly elsewhere and new white feathers on 

 the chin are the rule. Abrasion and fading make birds paler above and whiter 

 below. In this species, which is unique among our warblers during the first 

 breeding season in wearing an immature dress strikingly different from the 

 adult, the renewal is reduced to a minimum. 



Adult winter plumage acquired by a complete postnuptial moult in July. The 

 black and orange-red dress is assumed, the black feathers often having a faint 

 buffy edging. Sometimes the orange basal part of the primaries or of the 

 rectrices fails to develop and yellow, as in the first winter, takes its place. 



