The Chestnut-Sided Warbler {Dendroka pensylvanica) 



By T. Gilbert Pearson 



Description. — Adult male: Extreme forehead ashy white; crown bright yel- 

 low (gamboge) ; hind neck streaked black and ashy white; back and rump bright 

 olive-green, with partially concealed black stripes ; upper tail-coverts black, edged 

 with ashy and olive ; wings and tail black, primaries and rectrices edged with ashy : 

 secondaries and tertials edged with yellowish green ; two irregular wing-bars light 

 yellow ; three outer pairs of tail-feathers extensively white on inner webs ; a black 

 patch on the side of the head including eye ; an irregular white patch behind this ; 

 below white; sides of breast and sides with large chestnut patches, irregular or 

 interrupted; bill black; feet dark. Adult female: Like male, but duller; chestnut 

 of sides much restricted ; black face blotch divided by ashy, etc. No autumnal 

 change in either sex. Immature: Quite different; above bright, olive-green ; below 

 ashy or sordid white ; wing-bars and tail-blotches as in adult ; rectrices in unworn 

 plumage quite acute; bill light below. Length, 4.75-5.25 (120.6-133.3); av. of 

 six Columbus specimens: wing, 2.36 (59.9) ; tail, 1.91 (48.5) ; bill, .36 (9.1). 



Recognition Marks. — Smaller; white under parts and chestnut sides of adult; 

 light yellow wing-bars of young. 



Nest.^ — Made of bark-strips, grasses and plant-down, and lined with hair ; 

 placed two to ten feet high in bush or sapling. Eggs, 4 or 5, white or creamy 

 white, speckled with rufous or chestnut, chiefly near larger end. Av. size, .68x.50 

 (17.3x12.7). 



General Range. — Eastern United States and southern Ontario, west to Mani- 

 toba and th^ Plains, breeding southward to central Illinois, and northern New 

 Jersey, and in the Appalachian highlands probably to southern Georgia. Visits 

 the Bahamas, eastern Mexico, Central America and Panama in winter. 



Among the most charming birds in the world are the members of that group 

 classified as the family of Wood Warblers. There are about one hundred and 

 fifty-five known species, and they are found in no other country but America. 

 Seventy-four kinds occur in North America, and fifty-five of these have been 

 recorded in the United States. 



The}^ are small birds, the majority measuring rather less than five and one- 

 half inches from bill-tip to tail-tip. They are birds mainly of woods and thickets, 

 a few only venturing into open country. The W^arbler's bill is longer than that 

 of most small birds, and is well adapted for seizing the soft-bodied insects upon 

 which it so largely preys. 



One of the most common members of the family in the Eastern States is the 

 Chestnut-sided Warbler. The general appearance of the male is that of a par- 

 ticularly trim little bird with olive-green back and bright yellow crown ; the under 

 parts are lighter, and the sides are marked by deep chestnut — that is, this is the 

 way the male looks in spring. At this season the female is quite similar, although 

 its colors arc duller. In the fall and winter the plumage presents a very different 



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