Thursday, December 9, 2010


Friendship House 2nd and 3rd graders spent an afternoon this week looking and listening for owls on Norm's Island with Teacher Naturalist Adam Sundstrom. Adam introduced the students to the great horned owl, Bubo virginianus, in the classroom by showing them the wings and talons of a real owl. The class discussed the adaptations that help owls to be excellent hunters. They use their sharp feet (talons) to grab prey (usually small mammals like mice, though the great horned owl is the only animal that regularly eats skunks!). The feathers on their wings are fringed on the leading and trailing edges. This breaks up the wind as it flows over the feather, making for nearly silent flight so that owls can sneak up on unsuspecting small mammals. Additionally, the dish-shaped face of the owl helps to gather sounds, similar to the way a satellite dish gathers TV signals. The "horns" on the great horned owl are not its ears, they are actually just feathers. The ears of the owl are offset on the sides of its head (one side is higher than the other), which helps the owl to determine the precise location of prey. Oftentimes we see dogs tilt their head back and forth when they are listening; in doing so they are using the same principal of sound triangulation.

Armed with a portable wildlife caller that plays owl calls and mouse distress signals, the students headed to the field. As the evening approached and skies darkened, the students kept their eyes fixed on the trees, looking for camouflaged owls in the branches. When Adam played the owl's call, the students listening silently with the hope that owls would call back to the group. We didn't have luck this time, but we have seen great horned owls on the Island in the past and we'll keep looking. With luck, a pair will nest on the island sometime in February.

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