it depends on the water clarity. If the water is clear they will be much more spooky if the water is off color most times you can run on top of them. but the is this one lake that I like to fish that is stained and i fish in 4 to 6 feet of water and the crappie wil hold in the lilies and even with the trolling motor on low and being 8 to 10 feet away the crappie will still spook, you will see the water churn a little and the pads move, and when that happens i whont catch any out of that hole.
To land one of my crappie i need a gaff and a .22 pistal :D