GREAT HORNED OWL (Bubo virginianus) 



The great horned owl is the only large North American owl with ear tufts 

 or horns. It also has a finely barred stomach and a conspicuous white 

 -throat. Great horned owls inhabit cliffs and canyons and broken forest 

 habitats in both parks. Their prey includes grouse, squirrels, hares and 

 marmots, as well as small rodents and birds. Unlike most birds, owls have 

 binocular vision. The eyeball of this owl is as large as the eye of a human, 

 but tubular in shape. The enlarged lens-cornea portion of the eye allows 

 it to gather and concentrate all available light. Great horned owls also 

 have ears of unequal size which aid them in locating prey. The flight fea- 

 thers of the owl's wings have finely-toothed edges which allow the bird 

 to fly almost noiselessly. With these special adaptations, the great horned 

 owl is truly a marvelous predator. 



Great Horned Owl 



Alan G. Nelson 



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