Funny Gail should mention Cooper's hawks. I share the impression that 
there are many more around than, say, 15 years ago. In fact, one is, 
right now, calling 
"keh-keh-keh-keh-keh-keh-keh-keh-keh-keh-keh-keh-keh-keh-keh-keh" 
from our plum tree. I can hear it as I type this. It's an impressive 
orange-eyed adult bird and it's been sitting nestled in the 
porcelainberry-strangled tree crown for 15 minutes, calling. 
Yesterday I had a prelude when I saw, peripherally, two largish 
objects streak past our kitchen window, followed by a flurry of 
mourning dove feathers wafting down in the breeze. I don't recall 
hearing a Cooper's call like this, so consistently, in winter or late 
fall. Does anyone else hear them regularly?

Howard Youth

Bethesda, MD