Notes on the Plumage of North American Sparrows 



THIRD PAPER 



By FRANK M. CHAPMAN 



(Sec frontispiece) 



Sharp-tailed Sparrow (Fig. i). The i)ronounced buff markings, bruwn 

 crown stripes, and striking i)attern of the upper parts, are among the most char- 

 acteristic features of the Sharp-tail in fresh plumage. Worn summer birds lose 

 much of the buff on the breast and sides, which are then more sharply streaked, 

 but the buff on the sides of the head is still conspicuous. 



The nestling differs greatly from the adult, being entirely rich buff below, 

 usually more or less streaked on the breast and sides; the upper parts are dark 

 blackish brown, the feathers of the back, the wing coverts and tertials being 

 widely margined with yellowish brown. This plumage, as Dwight has shown, 

 is worn from the time the bird leaves the nest in late June or early July, until 

 September or early October, when, with the exception of the primaries, the 

 primary coverts and the secondaries (and sometimes all these), it is mohed and 

 replaced by the first winter plumage, which resembles that of the bird figured, 

 and is indistinguishable from that of the adult in winter plumage. 



As is usual with sedge-inhabiting birds, the effects of wear are soon apparent, 

 and midwinter specimens are as faded and worn as those of midsummer. Breed- 

 ing plumage is therefore acquired by a complete molt in March and April, when 

 the bird again acquires a plumage resembling that of fall. By the latter part of 

 May, the effects of wear and fading are apparent, and midsummer specimens 

 are almost white below, while the upper parts are dingy olive, almost if not 

 wholly unmarked. 



The seasonal changes in the plumage of both Nelson's Sharp-tail (Fig. 2) 

 and the Acadian Sharp-tail (Fig. 3) are similar to those just described. The 

 first named differs from the Sharp-tail (Fig. i) chiefly in being unstreaked or 

 but lightly streaked below, in having the upper parts richer and browner in tone, 

 with the scapular markings whiter and more pronounced, and in its smaller 

 size. 



The Acadian Sharp-tail (Fig. 3) is the palest of the three races. It is always 

 streaked below, but the streaks are dusky and not sharply defined; the buff is 

 much less rich and the back is grayer and greener, as the figure clearly shows. 



In worn summer plumage the New Brunswick specimens are markedly dif- 

 ferent from Shoal Lake, Manitoba, specimens of Nelson's Sharp-tail, the upper 

 parts of the latter bird at this season showing the effects of wear and fading but 

 litde. 



Nestling specimens of the Acadian Sharp-tail are usually unstreaked below. 

 The nestling plumage of Nelson's Sharp-tail appears never to have been de- 

 scribed. 



Seaside Sparrow (Fig. 5). The Seaside is a greenish gray bird with a yellow 



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