THE WESTERN RED-TAILED HAWK. 



(Buteo borealis caiurus.) 



The Western Red-tail is but a darker 

 variety of the red-tailed hawk so com- 

 mon in the eastern portion of North 

 America, where it is commonly called 

 "Hen Hawk." The v/estern form has a 

 long and narrow range covering that part 

 of North America between the Rocky 

 Mountains and the Pacific Ocean and 

 passing southward into^ Mexico. As a 

 casual visitor, it has also been observed 

 east of mountain system. It is only a 

 summer resident in the northern part of 

 its range. It is one of the earliest of the 

 migrating birds to return to its nesting 

 localities in the spring and one of the 

 last to wend its way southward in the 

 fall. Living in a mountainous region 

 and soaring over verdant fields where 

 innumerable cattle are feeding, no words 

 seem more fitting to its character than 

 those of the poet when he says : 



And yonder hawk, who fainter grows 

 Above the hills and grazing herds, 



Is symbol of the season's close, 

 The last of the departing birds. 



In its habits the Western Red-tail very 

 closely resembles its eastern relative. "It 

 is fond of the tall timber bordering the 

 banks of streams, and is as often found 

 far in the mountain passes and deep can- 

 yons aS' in the more open country in the 

 foothills and the adjacent plains, but 

 seems to shun the dense and extensive 

 forests and is rarely seen excepting on 

 the borders of these." Though usually 

 found in the vicinity of water courses it 

 has frequently been observed in desert 

 regions some distance from any stream 

 and has been known to nest in such lo- 

 calities. Their call notes are very simi- 

 lar to those of the common red-tail and 

 consist of "shrill squeals, uttered during 

 the greater part of the day while circling 

 high in the air." These notes are espe- 



cially noticeable early in the season as it 

 circles "high in the air in proximity to 

 its future summer home." A striking 

 characteristic is its attachment to a local- 

 ity where it has nested. To this site, it 

 apparently returns from season to season. 

 Nests have been found that were evident- 

 ly repaired and added to, year after year, 

 and in some cases the lower sticks had 

 become decayed. 



Though its nest is sometimes placed 

 very near the ground, it usually builds 

 at a height of from twenty-five tO' fifty 

 feet, and nests have been observed in 

 the tops of gigantic redwood and pine 

 ^ trees that were not less than one hundred 

 feet above the base of the tree. Several 

 species of trees are acceptable to this 

 Hawk as a place for its home, and it has 

 also been known to build its nest in a 

 species of gigantic cactus. When suit- 

 able trees are not to be found, the West- 

 ern' Red-tail is equal to the emergency 

 and will occasionally be satisfied with a 

 cliff or the "sides of a perpendicular 

 bluff" upon which to construct its home. 

 There is a record of such a nest that was 

 built on the side of a chalk bluff in south- 

 ern Colorado. It was situated at a point 

 "seventy-five feet from the bottom and 

 twenty feet from the top of the bluff." 



Though this species does occasionally 

 attack poultry and other birds, the name 

 "Hen Hawk" should never be applied to 

 it. The number of domestic fowls and 

 wild birds that it destroys is very small 

 when compared with the large number 

 of the noxious smaller mammals and 

 grasshoppers which it kills. When grass- 

 hoppers are common, they form this 

 Hawk's chief article of diet during the 

 months of late summer and early au- 

 tumn. The Western Red-tail is a friend 

 to the agriculturist. 



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