You'd think nine feet of wings supporting a 25 lb bird would make some racket, but you're right, they don't. I still see a few around here, surprised to see one just a couple months ago on my property after the influx of droves of large, loud, obnoxious, penned-up dogs in the area. I think the owls must live partly on feral cats, every other critter except a few stray whitewing doves have been driven off from the area and I can't see any other reason they'd want to be around the constant din of low-life "civilization" when they can fly two miles southwest and have almost an eternity of wooded, hilly wilderness with live water. Even the foxes and roadrunners have left here. Bunnies and Inca doves are long gone, probably cats and foxes ate all of those. Haven't heard a nighthawk since I was a kid.