It was 1:30 in the morning. Bryan woke me with “Listen.” Through the fuzz of sleep, I heard it—a pair of great horned owls singing their love songs to each other. They were somewhere in the woods on the northwest corner of Owl Acres. His voice was lower in pitch than hers, and their hoots and coos were a joyous jumble. It sounded like they were close, probably bowing to each other with drooping wings, touching beaks and preening as they murmured their marriage vows again for another year. Mated for life, they have by now staked out this year’s nesting territory, focusing on a hollow tree, or some other abandoned nest large enough to suit them. They’ll mate soon, if they haven’t already, and together they’ll raise two to four owlets over the summer. I didn’t hear this pair last summer, so perhaps they have moved into new digs this year. I hope so, although I’m not sure they will coexist happily with my barred owls.
Great horned owls (Bubo virginianus) have those ear tufts that are always depicted with owls in art and kitch. The tufts aren’t ears, though. They’re just feathers. The owl’s hearing, however, is amazingly acute. Its ears are positioned on either side of its head with one somewhat higher than the other. It doesn’t have the fleshy outer ear like mammals, but its entire face is shaped like a dish, and it acts like a parabola, gathering and concentrating sound. The uneven placement of the ears themselves allows the owl to pinpoint the origin of a sound both left to right like we can, and up and down in three-dimensional space. With this exact and acute hearing, a great horned owl can locate a mouse under several inches of snow, and with precision, capture it for its midnight snack. Like the barred owl, the great horned owl flies silently due to its specialized feathers.
Whereas the eagle and the hawk hunt by day, the great horned owl hunts at night. Not only is its hearing acute, but its vision is perfectly adapted to very low lighting. Its eyes are set close enough in its face to give it binocular vision similar to humans. Instead of being spherical, its eyes are shaped like a tube that gets larger at the back where the owl’s huge retinas capture and process light. Behind the retina is another light-enhancing surface called a tapetum lucidum. Like cats, their eyes shine in the dark.
Its eyes are fixed in its skull so it can’t move them. Instead it moves its head, turning it up to 270 degrees of rotation. This visual system gives the owl depth perception, lets the owl see very well in extremely low light, and lets it see what’s behind it as well as in front.
With an overall length of two to three feet, a wingspan of three to five feet, and a weight of from two to seven pounds, great horned owls are twice the size of the barred owl. They are mottled gray-brown with reddish-brown faces and a white patch at the throat.
Unlike the raptors of the daytime, owls don’t soar. Instead, they perch in trees and silently swoop down on their prey. They have strong, rounded wings and talons that dispatch prey instantly. These powerful birds have been known to capture and carry off prey that weighs two or three times as much as the owl does. Their preferred meal is rabbits and hares, but they’ll dine on all manner of small mammals, birds, snakes, frogs, and fish. They’ll eat roadkill sometimes as well. Most food is swallowed whole. The inedible bits—bone, fur etc., are packaged into owl pellets which are regurgitated before the next meal.
As I drift back to sleep listening to their music, I hope we hear this pair again soon. And I hope they’ll plan their little family in our neighborhood this year.
Photo by Montanabw