BIRD NOTES AFIELD 



eye. Tail dark, with four or five blackish bars. The immature birds 

 are dark brown above, irregularly mottled with reddish brown and buff, 

 especially about the head; below white, with firm spots and stripes of 

 dark brown. Tail distinctly barred and white tipped. An inhabitant of 

 the dense forests of the Sierra Nevada Mountains. 



19. Western Red-tailed Hawk; Buieo borealis calurus (Cass.). 

 Very variable in color. Length of male twenty-one, of female 



twenty- four inches (about the size of the preceding). Adult, above 

 grayish brown or blackish brown, mottled with rusty; below varying 

 from white or buff, more or less streaked with brown dusky markings, to 

 dark blackish brown. The distinctive mark is the bright reddish brown 

 tail, edged with buff or whitish and with one or more blackish bars. The 

 immature birds are similar to the adult, but tail more distinctly and 

 numerously barred, and grayish brown in color. The most abundant 

 and widely distributed of the larger hawks of California, breeding gen- 

 erally. 



20. Red-bellied Hawk; Buteo lineatus elegans (Cass.). 



This is the western variety of the red-shouldered hawk. Length of 

 male eighteen, of female twenty inches. The prevailing shade of the adult 

 is rich reddish brown, varied with dark brown; the wings and tail are 

 blackish brown, varied with conspicuous white markings. The rusty 

 shade is most continuous and pronounced on the shoulders and on the 

 under parts, the belly barred with white. The general color below is 

 decidedly lighter than above. The tail has several narrow, distinct white 

 bars. Immature birds are dark brown above, with the head and lower 

 parts white, closely streaked with brown. This species appears to be 

 resident chiefly in the interior valleys of central and southern California. 



21. Swainson's Hawk; Buteo srvainsoni Bonap. 



Length of male twenty, of female twenty-two inches. Above dark 

 brown, the forehead narrowly edged with white at base of bill. Upper 

 lail-coverts white, barred with brown. Below brown, the throat pure 

 white or white finely lined with brown; belly varying from white to 

 creamy buff or chestnut, with or without brown bars. This species is 

 often melanistic, that is with a very dark brown plumage continuous 

 above and below. An inhabitant chiefly of the wooded valleys of the 

 State. 



22. American Rough-legged Hawk; Archibuteo lagopus sancii- 

 johannis (Gmel.). 



Length averaging about twenty-two inches, the male generally smaller 

 than this and the female often larger. This species is so variable in 



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