WESTERN BIRDS Bluebird 



GENUS SIALIA: CHESTNUT-BACKED 

 BLUEBIRD. 



Chestnut-backed Bluebird: Sialia mexicana bairdi. 

 FAMILY— THRUSHES, BLUEBIRDS, ETC. 



This bird is similar to the Western Bluebird, the chief 

 difference being that the fore-back is wholly chestnut. 

 It is found in the Rocky Mountain Region from Utah, 

 Colorado, and western Texas, south. 



They are, primarily, dwellers of the mountains, breed- 

 ing as high as 9,500 feet in Colorado. Sometimes, how- 

 ever, venturing down to the foothills to nest, and scat- 

 tering through the valleys and plains during the winter 

 and migrations. 



GENUS SIALIA: SAN PEDRO BLUE- 

 BIRD. 



San Pedro Bluebird: Sialia mexicana anabelce. 



FAMILY— THRUSHES, BLUEBIRDS, ETC. 



According to the A. 0. U. Check List, this subspecies 

 ranges from the mountains of southern Los Angeles 

 County, south to Lower California. Willett says of it: 

 "The Bluebirds of the extreme southern end of the State 

 are intermediate between this form and the last (West- 

 ern), and are not typical of either." Robert Ridgeway 

 says: "Specimens from San Diego County and southern 

 Los Angeles County are much nearer this form than 

 they are to occidentdlis." This bird is an abundant 

 breeder in the San Bernardino and San Jacinto Moun- 

 tains and, according to L. Belding, breeds commonly 

 in the timbered parts of San Diego County. 



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