AMERICAN BARN OWL 145 



Mr. Sumner's plates (1933) show that at an age of 26 days the 

 primary quills are beginning to burst their sheaths, but the wing 

 coverts are still downy; at 44 days the primaries are well advanced, 

 and the down is rubbing off, disclosing the first winter plumage; at 

 66 days the development of the wing is practically complete. 



Potter and Gillespie (1925) describe the development of their young 

 barn owls as follows: "Pin feathers in wings appeared in approxi- 

 mately twelve days. Primaries and tail feathers acquired in approxi- 

 mately three weeks. Complete wing and tail feathers acquired in 

 five to five and a half weeks. Complete adult plumage acquired in 

 approximately seven and a half weeks." 



Most authors state that the first winter plumage, which is the first 

 real plumage, is like that of the adult, but it seems to me that there are 

 some slight differences; the gray "pepper and salt" markings on the 

 upper parts are less extensive and more mixed with buffy tints; the 

 crown and hind neck, which are uniform with the back in adults, vary 

 from "cinnamon-buff" to "cream-buff", sparingly spotted with the 

 black and gray spots. 



This plumage is worn, without molt and with very little abrasion, 

 until the annual, complete molt, which takes place in both young and 

 adult from July to November. There seem to be two color phases in 

 adults, which Baird, Brewer, and Ridgway (1905) describe as follows: 

 "Darkest: There is no white whatever on the plumage, the lower 

 parts being continuous light ochraceous; the tibiae have numerous 

 round spots of blackish. Lightest: Face and entire lower parts 

 immaculate snowy-white; facial circle white, with the tips of the 

 feathers orange; the secondaries, primaries, and tail show no bars, 

 their surface being uniformly and finely mottled. * * * The 

 variations of plumage noted above appear to be of a purely individual 

 nature, since they do not depend upon the locality; nor, as far as we 

 can learn, to any considerable extent, upon age or sex." 



However, in a large series that I examined, I noted that the males 

 averaged lighter above and whiter below, often pure white below, 

 with only a few scattered small spots of sepia, and with whiter faces. 

 The females, on the other hand, averaged darker everywhere, the 

 breasts, flanks, and tibiae being often "cinnamon-buff", deepest on the 

 tibiae, with more, larger, and darker spots; and the faces were more 

 tinged with brownish. As this was not a universal rule, however, it 

 may mean only individual variation, or indicate two color phases. 

 Similar variations were evident in the younger birds, so it is not an 

 age character. 



Food. — All authorities agree that the barn owl is one of our most 

 useful birds of prey, as its food consists almost entirely of various 

 species of rodents that, from their abundance and destructive habits, 

 are a curse to agriculture and other human interests. Dr. A. K. 



