BLACK-THROATED BLUE WARBLER. 



654. Dendroica caerulescens. 5% inches. 



Male, grayish blue above and with a black face, 

 throat, breast and sides; female, grayish olive above, 

 whitish below. Both sexes always have a white patch 

 or speck at the base of the primaries. 



You will find these birds in damp woods or swamps, 

 or less often in parks or open woods. They are usually 

 seen at low elevations in scrubby underbrush. Their 

 notes are very peculiar and will draw attention to 

 them anywhere. 



Song. A deep grating whistle with a sharply rising 

 inflection, zee-zee-zwee. 



Nest. In deep, swampy woods, especially common 

 in laurel; of grape vine bark and rootlets lined with 

 fine black roots and hair; the four eggs are white or 

 buffy white with reddish brown spots and blotches. 



Range. Eastern N. A., breeding from Connecticut 

 (sparingly) and Michigan north to Labrador and Hud- 

 son Bay; winters in Central America. 654a. Cairns 

 Warbler (cairnsi) is said to be darker on the back; 

 found in the southern Alleghenies. 



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