BIRDS OF PREY 209 



taken as far east as the States of Illinois and Wisconsin. 

 It is replaced in the Arctic regions by the Arctic Horned 

 Owl, which is lighter in color, its range only reaching as far 

 south as Idaho and South Dakota. The Western horned 

 owl breeds nearly throughout its range. 



It feeds on grouse and ducks, as well as other species of 

 valuable food water birds. It also kills many forest birds 

 that are useful to man as insect destroyers. It is said that 

 they will feed on mammals, such as polecats, prairie dogs, 

 squirrels, rabbits, and other rodents. But this is not the 

 worst crime of this marauder, for when it visits the more 

 thickly inhabited districts it appreciates the delicacies to be 

 found in the poultry yards of the farmer, and kills far more 

 than it needs to satisfy its appetite. 



"While perhaps the majority of these birds resort to 

 hollow trees or old nests of the larger hawks and of the 

 common crow, quite a number nest in the windworn holes in 

 sandstone and other cliffs, small caves in clay and chalk 

 banks, in some localities on the ground, and, I believe, even 

 occasionally in badger holes under ground." 



It is said that the Western horned owl will lay two or 

 more sets of eggs at short intervals if the nest and eggs 

 are disturbed. The number of eggs laid is usually two or 

 three, and infrequently four are found, and sets of five and 

 six have been reported. The eggs are white, showing, as 

 a rule, but little gloss, and are roughish. In form they are 

 rounded oval, about two and one-half inches long, and 

 nearly two inches in diameter. The period of incubation 

 lasts about four weeks, and it is said that only the female 

 sits on the eggs, the male furnishing her with food. 



