324 MICHIGAN BIRD LIFE. 



red phase and others the gray phase, and this whetlicr both parents are 

 red, both gray, or one red and the other gray. It has been shown that in 

 captivity the gray bird can be converted into a red one by feeding regularly 

 with liver, and by withholding this food afterwards the bird has eventually 

 resumed the gray plumage. This would seem to indicate that the color 

 of the plumage may be largely influenced by the character of the food, 

 yet it is difficult to see how this fact can be used to explain the conditions 

 actually found in nature. 



TECHNICAL DESCRIPTION. 



Small; ear-tufts (plumicorns) large and conspicuous; four or five outer primaries emargi- 

 nate or sinuate on inner webs; iris yellow; bill variable, but never white; toes scantily 

 feathered toward their tips. 



Adult in Gray Phase : Upper parts brownish-gray, more or less mottled with blackish, 

 many feathers of tlie top of head and back with black shaft-streaks; outer edge of many 

 scapulars white or whitish, forming two conspicuous light stripes down the back; facial 

 disk gray with much dusky mottling, and bounded on its outer edge by a clear black 

 border which is continued down the side of throat as a black stripe; under parts white or 

 grayish white, with conspicuous black streaks and much finer and fainter wavy cross-bars 

 of dusky or black; outer webs of wing feathers with numerous white or buffy spots or 

 patches, the inner webs barred with blackish and gray; tail gray with six to eight narrow 

 dusky bars. 



Adult, Red Phase: Prevailing color bright rust-red, sometimes uniform above except 

 for the white scapular stripes and an occasional blackish shaft line on forehead and 

 scapulars; under parts mixed rust-red and white, usually with some black streaks, but 

 sometimes all the markings very deep red; facial disk rusty gray, commonly bordered by 

 black as in the normal phase; wing feathers and tail with same pattern as in normal bird, 

 but the bars mainly of light and dark rusty, only partly blackish; bill reddish. 



Between these two extremes of gray and red, are found intermediate forms of every 

 possible gradation, but the size and proportions will always discriminate it from the Long- 

 eared Owl, and tlie ear-tufts prevent confusion with any other. 



Length 7.50 to 10 inches; wing 6 to 7.10; tail 3.05 to 3.50. 



157. Great Horned Owl. Bubo virginianus virginianus {GmcL). (375) 



Synonyms: Virginia Horned Owl, Big Hoot Owl, Cat Owl. — Strix virginiana, Gmel., 

 1788, Wils., Aud. — Bubo virginianus, Bonap., Nutt. — Strix maximus, Bart., 1792. — 

 Bubo pinicola, Vieill., 1807. 



Plates XXX and XXXL 



Our largest common owl, readily identified by the conspicuous ear-tufts. 

 Any tufted owl with a spread of wings of four or five feet may be safely 

 identified as the Great Horned Owl, or its western variety, No. 158. 



Distribution. — Eastern North America, Avest to the Mississippi Valley, 

 and from Labrador south to Costa Rica. 



Generally distributed throughout the state, but more abundant in the 

 unsettled portions than elsewhere. As the country is cleared up and gunners 

 become more numerous this species becomes less and less common, although 

 doubtless a few pairs continue to rear their young even in the most populous 

 districts as long as any considerable patches of timber remain. It appears 

 to be resident wherever found and we know of nothing to indicate a migratory 

 movement, the great abundance at certain seasons or during certain years 

 being due probably to an increase in the total number of individuals, or 

 possibly to a concentration brought about by favorable food conditions. 



The Great Horned Owl is mainly nocturnal in its habits, but if found 

 abroad during daylight appears to see fairly well and is usually a rather 



