The Oregon Juncoes 



No. 51a Coues's Junco 



A. O. U. No. 567b. Junco oreganus couesi Dwight. 



Synonyms. — Washington Junco. Hybrid Snow-bird (Coues). Rocky 

 Mountain Junco (Coues). Shufeldt's Junco. 



Description. — Adults: Similar to J. 0. oreganus, but back (in males) less 

 rufescent, more grayish (pale olive-brown to dull army-brown) ; in females snuff- 

 brown; black of head and throat a little more slaty; also averaging larger. Length 

 152.4-165 (6.00-6.50); wing 80 (3.15); tail 69 (2.72); bill 11 (.43); tarsus 21 (.83). 



Recognition Marks. — Sparrow size; black of head and throat contrasting with 

 brownish gray of back and with white of breast; grayer on back than preceding. 



Range of /. 0. couesi (as defined by A. O. U. Committee under name Junco 

 hyemalis connectens). — Rocky Mountain region, breeding from coast of southern 

 British Columbia, east to west central Alberta, and south to northern Oregon; win- 

 tering over entire Rocky Mountain tableland to eastern Colorado, Arizona, New 

 Mexico, western Texas, Chihuahua and Sonora. Casual in northern Lower California. 



Occurrence in California. — See general discussion below. 



THE CASE of our northwestern wintering Juncoes is involved in 

 notable confusion. All depends upon definition of the summer ranges of 

 the three related forms, oreganus, couesi, and thurberi. 



There is least question regarding oreganus, for that subspecies now 

 breeds entirely north of the United States, probably no further south 

 than the Queen Charlotte Islands; and its contributions to the winter 

 population of northern California are perfectly manifest by reason of the 

 decided rufous of their backs. 



But the case of couesi is more involved. As now defined by the 

 A. O. U. committee (Check-List, 3rd Edition, 1910) couesi (formerly named 

 connectens) includes not only the breeding birds of the Rocky Mountains 

 in eastern British Columbia, but also those of Vancouver Island and 

 Puget Sound. Either this is correct, or the Puget Sound specimens 

 represent a northward extension of thurberi, or else they deserve recog- 

 nition as a separate subspecies. In any event, these Puget Sound and 

 southern British Columbia breeders must winter more or less in northern 

 California; for they largely forsake their summer home, and their place 

 is taken by oreganus. If, however, these southern winter- taken speci- 

 mens of hypothetical couesi are not actually separable from thurberi, 

 we shall have to restrict the range of couesi to the northern interior, and 

 recognize an enormous northwestern extension of thurberi. 



The situation has probably been complicated by recent rapid move- 

 ments in the case of all these forms. Oreganus, at least, was the recog- 

 nized breeding bird of Puget Sound no later than 1903. 



We have here an indubitable instance of that northward trend of 

 species clearly recognizable in the East, but obscured to our vision in 



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