But you would need to if you want it for it's moneytary value. Even selling in piece by piece on a black market, which is quite hard to do, will require you to advertise it.
However my guess is that whoever is smart enough to find it is smart enough to solve this problem as well.
> He has also affirmed that hiding the treasure in the first place was largely about encouraging families to enjoy the outdoors. “I wanted to give the kids something to do,” he said. “They spend too much time in the game room or playing with their little hand-held texting machines. I hope parents will take their children camping and hiking in the Rocky Mountains. I hope they will fish, look for fossils, turn rotten logs over to see what’s under them, and look for my treasure.”