GREAT question. I hunt both Maine and NH so carry both licenses and I've hunted boundary waters for years. I treat the boat ramps the same way as driving over a bridge. I hunt New Hampshire water and launch in Maine, but not the other way around. I've asked game wardens from both states, pretty gray area, just make sure your are following whichever states' laws you are hunting in. I would make sure I know the lines on the water. Take Sundays for example. I hunt a spot in N.H. but the ramp is in Maine, no hunting on Sunday in Maine either. I launch, gun and everything cased as it would be in my truck, drive across the lake, like going over a bridge, and then set up on the N.H. side of the lake. If questioned, I can prove where I was, the boundary line is on the map and I'm always over the line on the other shore. This also could come into question when Maine's southern season is closed and N.H. is still open and vise-versa. Always good to call your local Wildlife law enforcement to get their take on it too. If you find out something different, please post it up.
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