Very cool. Thanks for posting. I'm not too well educated on that subject but a lot of it sounded familiar. Got a lot of woods around me and it's pretty silent until spring. Then I walk outside at night and listen for saw-whet owls. Lotsa hawks around and I know their noise. Had a sharp shinned hawk sitting in the trees in the woods next door Saturday. Overlooking my bird feeder... Had to get my field guide out to I.D. him, and it says they're often seen near feeders. Got out the Canon Rebel with the telephoto lens and when I went to photograph him he had vanished.