What Guy said; calling and faces. We've all had the experience of walking out into the spread for some reason, looking back at the blind and telling someone their face was shining like a 1000 watt bulb. If/When the sun can shine into the blind, some way to disguise the face is crucial. Re: calling, I believe overcalling - and guys doing the highball/comeback call trying to sound like the "pros" do in calling contests - to be one of the most effective conservation measures available to ensure a healthy population of wild ducks. : ) I have been hunting ducks since my now distant early teens, and I have never heard a duck make anything vaguely resembling much of what I hear out there. Inappropriate calling as well as simple over calling. IMO the lazy hen-on-the water is one of the most effective calls for finishing. Not flashy but effective. I don't believe I'm the only guy out there who's had his attention drift away from the sky - to the dog, or a frozen call, or lunch, or coffee, or, or, or... - and looked up to find birds locked up or even sitting in the decoys, without anyone so much as giving them even a feeding chuckle. I've never had the discipline to test the theory, but I've often thought about going out without the calls. So long as there was enough movement in the water to give the dekes some life, I suspect that I might not have too bad a day w/o calling at all. I have had days where I was either surrounded by kazoo players or where I became convinced that the ducks were call-shy, and where I really backed off the calling, and started having more success than when calling as I might normally do. A bad set-up can and does flare birds, but I've had ducks drop into a spread w/ dead birds in the water, or a sinking decoy or two, or two or three dekes "kissing," that I am not convinced that a bad set-up is as deadly as are shining faces - and hands - and bad calling/over calling.