160 BULLETIN 17 0, UNITED STATES NATIONAL MUSEUM 



of the posterior under parts. In full first-winter plumage young 

 birds are practically indistinguishable from adults. 



Adults have a complete annual molt in the fall, from September to 

 December. There is considerable individual variation, but, in the 

 series I have examined, males average paler and with more white on 

 the under parts than females. Dr. Oberholser (1922) says that there 

 are "at least four color phases, these being a light and a dark ochra- 

 ceous phase, and a light and a dark gray phase." These phases are 

 none too well marked in a series of more than 70 specimens that I 

 have examined, and they look more like individual variation, though 

 there are more gray birds among the males and more ochraceous birds 

 among the females. 



Food. — The long-eared owl is unquestionably worthy of protection 

 as one of our most beneficial birds of prey, for a very large proportion 

 of its food, probably close to 80 or 90 percent on a seasonal average, 

 consists of injurious rodents. Many of these owls have been shot as 

 destroyers of game birds or rabbits, but, among hundreds of records, 

 I can find only one record of a quail and two of ruffed grouse being 

 killed, and very few records of young rabbits. There seems to be no 

 record of domestic poultry being attacked. 



Dr. A. K. Fisher's (1893b) summary states that "of 107 stomachs 

 examined one contained a game bird [the quail referred to above]; 15 

 other birds; 84 mice; 5 other mammals (including one young rabbit); 

 one insects and 15 were empty." In a lot of pellets collected near 

 Washington, D. C, he found 17G skulls or parts of skulls, among which 

 only 13 were of birds, and the remainder were of various mice and 

 shrews. Dr. B. H. Warren (1890) "examined the stomachs of 23 

 long-eared owls and found that 22 of them had fed only on mice." 

 Dr. Paul L. Errington's (1932c) pellet records for Wisconsin show 

 that, during fall, winter, and early spring, mammals, mainly mice, 

 make up 99 to 100 percent of the food; and during late spring and 

 summer this percentage drops to between 87 and 92 percent, the per- 

 centage of birds running from 7 to 12 percent. His summary states: 

 "Total vertebrate kills from pellets and stomachs (quantitative data) 

 amount to 3,273 ; juvenile cottontail, 1 ; Norway rat, 3 ; meadow mouse, 

 2,732; deer mouse, 497; shrew, 14; small bird (mostly finches), 26." 

 In two cases flocks of quail were wintering near where his owls were 

 roosting, but he found no evidence that the owls ever molested the 

 quail. 



On the other hand, Dr. Charles W. Townsend (1918) had a collec- 

 tion of pellets examined, w T hich he had found under a nest in June at 

 Ipswich, Mass., and reported that the "owls had eaten some 13 

 different species of birds and 23 individuals; also 4 species of mammals 

 and 25 individuals." This and Dr. Errington's summer records indi- 

 cate that birds are taken in quantity only during the season when the 



