Thankfully, we don't live in a state where it's legal and/or common practice to shoot at trespassers. Try applying Mike's addage out west and you might end up with some bird shot in the arse as response to your pleas for forgiveness. Have I ever told you guys my Canyon City brookie stream story?
But this ain't the west, so I'm with Sir Powers. Fish it like you own it, and if anyone gives you a hassle, just tell them the helicopter is coming back for you in a few minutes.