Great Horned Owls
Great horned owls (Bubo virginianus) are one of the largest and most familiar of all North American owls. They are known as “hoot owls” because of their deep resonant hoo hoo-hoo HOO HOO that can be heard for miles. The “horns” that give these owls their name are tufts, not ears, and are used in part for aggressive displays.
The owls use their sharp senses – particularly hearing, but also vision and smell – to hunt rats, rabbits, voles, snakes and gophers. Their sensitive ears, which are farther down the sides of their heads, are not as visible as the great “horns”. (The tufts are also used to funnel sound to the ears.) The eyes of the great horned owl are so large that they leave little room in the skull for muscles that would move them. Instead, the owl has fourteen vertebrae its the neck, allowing the head to turn in the characteristic owl swivel. (Humans only have seven!)
Great horned owls begin nesting as early as January. They usually take over the old nests of herons, hawks or crows. Owls will nest in anything large enough to hold the huge birds and all the bones and debris collected while feeding two owlets, which eat their weight in mice and other small animals each day. Both the male and female take turns incubating. Like most birds, owls develop an incubation patch where bare skin is supplied with extra blood. By the time the nest becomes too crowded for the big babies and trash, the owlets begin to leave it. This happens in the spring, at about the same time small birds and mammals are available as food.
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