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BLACK-THROATED GRAY WARBLER 



Young d, Fall. Similar to adult d in Fall but generally no black in back, 

 chin white, throat usually more or less mottled with white, sides browner, no 

 white on secondaries. 



Adult ?, Spring. Similar to adult d in Spring and sometimes not dis- 

 tinguishable from it, but, as a rule, with less black on the head, back browner 

 and less heavily streaked; wings and tail browner and with less white; throat 

 and upper breast mottled with black and white. 



Adult ?, Fall. Similar to adult $ in Spring but upperparts and cheeks 

 washed with grayish brown, black of throat margined with white, sides tinged 

 with brown, the black streakings obscured. 



Young $, Fall. Not certainly distinguishable from adult $ in Fall but often 

 with less black. 



Nestling. Above brownish gray, a broad whitish postocular stripe; below 

 gray, belly white, breast lightly streaked; wings and tail as in young. 



General Distribution. Western United States. 



Summer Range. Breeds from northern Lower California, 

 southern California, southern Arizona and New Mexico; north to 

 British Columbia and east to central Colorado (Idaho Springs). 



Winter Range. Winters in Mexico. 



Spring Migration. The species enters southern California the 

 first week in April and reaches southern British Columbia the third 

 week in the month. The earliest dates in southern Arizona and 

 southern New Mexico are included between April 6 and April 9; 

 while the species appears in the northern portion of its Colorado range 

 early in May. 



Fall Migration. The last birds do not leave central California 

 until the first week in October and the species does not desert the 

 State until after the middle of the month. 



The Bird and its Haunts. "These birds are very plentiful during 

 the breeding season in the mountains of southern Arizona. They may be 

 found from an altitude of 4,000 to 9,000 feet, but are more common in 

 the oak belt, from 4,000 to 7,000 feet altitude, where a great many of 

 them breed. Nevertheless, comparatively few nests are found. I be- 

 lieve the reason for this is, because, unlike other Warblers, these birds 

 do not have a note of alarm nor do they show any signs of breeding. 

 The birds are constantly on the jump, apparently catching insects. 

 Even when flushed from the nest they will hop about in their usual 

 unconcerned manner." (Horvard*.} 



Of this Warbler in California Walter Fisher writes : "The Black- 

 throated Gray goes about its affairs in a quiet business-like manner 

 suggesting the Lutescent Warbler, and differs, therefore, in tempera- 

 ment from both the Calaveras and Audubon Warblers which are 

 always in evidence. It lives in chaparral such as deer brush, wild lilac 



