EASTERN WHITE-CROWNED SPARROW 1281 



parts white, or lightly tinged with buff on chest, sides, and erissum. 

 Chest, sides, and flanks heavily streaked with black. Belly and 

 erissum immaculate. Leg feathers dark brown, edged with white." 



Jonathan J. Dwight (1900) presumes that the first winter plumage 

 is "acquired by partial postjuvenal moult, probably in August on its 

 breeding grounds, which apparently involves the body plumage and 

 the wing coverts partly but not the rest of the wings nor the tail." 

 This is the "brown livery," the conspicuously more buffy immature 

 plumage, in which the head is marked by broad reddish-brown stripes 

 instead of the black and white of the adult. 



Dwight also writes that first nuptial plumage is "acquired by a 

 partial prenuptial moult beginning the end of March which involves 

 chiefly the head and chin and a few scattering feathers elsewhere. 

 The black and white crown is assumed, which soon shows nearly as 

 much wear as the rest of the plumage. This becomes grayer and the 

 stripes clearer. Old and young become practically indistinguishable" 

 at this stage. Furthermore, "adult winter plumage [is] acquired by 

 a complete postnuptial moult." 



Robert A. Norris (1954) reports an extensive prenuptial molt during 

 March and April, except for "the alulae, the primaries, secondaries 

 and their greater (outer) coverts, the ten outside tailfeathers, and 

 some of the feathers of the "wing lining." He felt it was "fairly 

 certain that nonmolting birds such as my mid-March specimens would 

 show * * * overlap between periods of molt and migration," assuming 

 that completion of the molt requires 2 months. 



Amelia R. Laskey of Nashville, Tenn., wrote Mr. Bent that she 

 noticed unusually early beginning of crown molt during the first week 

 of November 1932 and again in 1934. In the experience of both 

 Mrs. Laskey and Ralph Bell, crown molt is normally complete by late 

 April. Bell's notes show that crown molt takes at least 20 days. 



Food. — Perhaps the most interesting item on the food of white- 

 crowns is Francis Harper's (1958) discovery that in spring on the 

 breeding grounds, these birds eat the green capsules of Polytrichuin 

 juniperinum, the hairy-cap moss. In 1957 I watched one bird pick 

 and eat 120 capsules in exactly one minute. A female collected on 

 June 8 had nothing but these capsules in her crop, and though all the 

 white-crowns were utilizing this food at the time, some birds also 

 picked up small brown seeds, a few sand grains, and black flies 

 {Simulium sp.). 



Like other terrestrial passerines, the white-crown is an opportunist. 

 The hairy-cap moss capsules it consumes in late May and early June, 

 when snows have just melted but before many insects emerge, are at 

 that time the most available food. I have watched them eat the new 

 green catkins of willows. The young are fed insects as nestlings, and 



