BIRDS OF PREY 



(342) Buteo swainsoni Bonap. 



SWAINSON'S HAWK. Three 

 outer primaries notched. The back, 

 wings and tail are blackish-brown 

 in all plumages, but the under parts 

 vary almost indefinitely. A per- 

 fectly plumaged cf is shown. The 

 9 has the breast darker, almost ma- 

 hogany colored, and the under parts 

 are heavily cross-barred with chest- 

 nut or blackish. One plumage, per- 

 haps a dark phase, is uniform blackish- 

 brown. Immature birds have the 

 under parts pale 3'ellowish-brown, 

 heavily streaked on the breast and 

 lightly barred below with brownish. 

 L , 20.00; W., 1.5.50; T., 8.75. Eggs 

 — White spotted with brown; in 

 trees or on ledges; 2.20x1.70. 



Range — Breeds from Man., Mac- 

 kenzie and Alaska south to Chile. 

 Casual east of the Mississippi River. 



wholly insectivorous. Their nests are placed in the tops of 

 bushes, rarely more than ten feet above ground. 



SWAINSON'S HAWKS are common and widely distrib- 

 uted in western North America, but are only of casual 

 occurrence east of the Great Plains. They probably exhibit 

 greater diversity of plumage than any other species, the 

 handsomest and t^-pical adult plumage being the one shown 

 here. They show less fear of man than most other species 

 are wont to do. Their food is made up almost entirely of 

 small rodents and insects such as grasshoppers, crickets, etc. 

 That they do not prey upon small birds is very evident when 

 it is considered that nests, in use, of this hawk, Bullock's 

 Orioles, Arkansas Kingbirds, and grackles have been found 

 in the same tree, and the two latter species sometimes 

 build their homes among the sticks composing that of the 

 large hawk. 



Their nesting sites vary fully as much as their plumages. 

 These may be the tops of tall trees, sixty or more feet from 

 the ground, or they may be in bushes not more than four 



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