Good plan; I've never tried that. We always just waited as close to the water as possible, and either the game would just stroll straight-in, or else it would approach to well-within range before hitting the wall and pausing bewildered long-enough to collect a bullet. That may save you some leg work, and I suspect it will be easier to stay concealed closer and surprise the blighters than to approach concealed (at least with the camels and dogs). Try both! Although it may be dictated by available shade.