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KED TAILED HAWK. 

 Buteo borealis. 



DESCRIPTION. 



The adult is easily i-ecognized by its I'ed tail. The tails of 

 young birds are usually ashy-brown, with about ten darker 

 bands. Tail in both old and young is generally tipped with 

 white. Breast of adult mostly spotted or marked with reddish 

 brown; in the young, breast is pure white enclosed by 

 numerous dark markings. Length of male, 19 to 22 inches; 

 extent of wings, 41 to 47 inches. Female, length, 22 to 24 

 inches; extent, 51 to 55 inches. From a careful examination of 

 over one hundred of these hawks, I have found that they, 

 like other of the raptores, not only vary greatly in the mark- 

 ings of their plumage, but also show marked differences in 

 the color of the irides. The iris of the adult, though usually 

 brown, is sometimes both ))rown and yellowish. In immature 

 birds the iris is commonly straw color, but sometimes it is 

 nearly white, and occasionally, though rarely, is brown; in 

 other specimens I have seen one-half of the iris brown while 

 the remainder would be white or yellowish. 



In immature birds, light-colored irides with specks of brown 

 are frequent. 



B'abitat. — Eastern North America, west to the great plains. 

 Common and breeds generally throughout Pennsylvania. 



This hawk, one of the most abundaut of our i-aptorial 

 birds, is the hirge ''Hen Hawk" of the farmer. The 

 Ked-tailed Hawk is exceedingly shy and wary, and is 

 laken with difficulty, unless approached on horse-back 

 or in a sleigh or wagon. Red-tailed Hawks in their 

 fall migrations are gregarious. One clear, cold au- 

 tumn afternoon in 187G, I saw, near West Chester, a 

 tlock of these hawks. The sky was destitute of clouds, 

 except a cumulus stratum directly beneath, and ap- 

 I)arently about half-way between the hawks and the 

 earth. In the center of this vapor was an opening of 

 sufficient size to enable me to watch the gyrations of 

 the birds; two of them suddenly separated from the 

 main body, api)roched each other screaming, and ap- 

 parently in great rage. They descended screaming, 

 12-TT 



