142 THE HAWKS AND OWLS OF THE UNITED STATES. 



breeds in common with otlier species in tlie precipitous cliffs bordering 

 the canons. Whether it ever builds its own nest, especially those 

 which are found on the ground or in the cliffs, is an open question. 

 The eggs are from three to six in number, live being the most common, in 

 theexperience of the writer. Throughout the middle of its range the eggs 

 are deposited usually from the latter part of March to the first week in 

 April, and toward the northern limit it is probably the last of April 

 before the sets are completed. In the southern part of California 

 it nests considerably earlier, as full sets of eggs are found by the lat- 

 latter part of February. Capt. Ben dire states that the period of incu- 

 bation is about three Aveeks. In June the young leave the nest and 

 may be seen with the old birds in some dark retreat. While the female 

 is sitting the male is usually near by, either on the edge of the nest 

 beside her, on a branch of the same or an adjoining tree or occasionally 

 on the ground underneath. 



This species, like the Screech Owl, is nocturnal in its habits, and 

 differs from the Short-eared Owl in never hunting during the daytime. 

 It usually spends the day in some evergreen woods, thick willow copse, 

 or alder swamp, although rarely it may be found in open places. On 

 one occasion in October, in the vicinity of Boston, the writer, in com- 

 pany with Messrs. John H. Sage and H. A. Purdie. found one of these 

 birds sleeping among some small deciduous trees which had lost most 

 of their leaves. 



Throughout the eastern part of the United States, solitary birds, or 

 less frequently a pair, are usually fouiul during the winter months, while 

 it is common to find small bands or families of six or seven together in 

 summer and early fall. In certain parts of the West the species is gre- 

 garious and often as numerous as the Barn Owl. 



Mr. H. W. Henshaw says: " It seems to be a habit with this species 

 in the West to congregate together and form colonies, often made up 

 of a large number of individuals. I have, however, noticed this to be 

 most frequently the case in regions where timber was scarce, and doubt- 

 less this lack of places suited to the necessities of their nature, which 

 requkes them to pass the hours of daylight in some dark, secluded re- 

 treat, furnishes the reason for this apparent sociability. In Grass 

 Valley, Utah, I thus found at least a dozen individuals together in a 

 small grove of cedars, and nearly every tree contained one of their 

 nests, rudely made of coarse sticks, while some supported two or three. 

 The birds were roosting on the low branches in the darkest portions 

 of the clumi), and they were generally so well concealed that I saw 

 them only as they dashed hurriedly out when I was close upon their 

 retreats" (Explor. West of the 100"' Merid., Wheeler, vol. v, 1875, p. 

 403). And Capt. Bendire speaks of seeing some fifteen or more on a 

 single mesquit tree, near Rillito Creek, Arizona. 



Although quiet during the day, and apparently indisposed to ven- 

 ture into the strong light, when started it is able to thread its way 



