re: What's the 2nd most important factor in duck hunting success?

I say feed.

Being a primary marsh hunter when we get a storm and there is no feed, it doesn't matter what the weather does how many decoys, what kind of call, or shot placement, or movement of birds without feed there is no birds.

My other opinion would be to have birds, if you don't have birds in the area you are hunting it's gonna be a long day.