Sorry, sir, but there is a reason, unfathomed by the human mind, that all things exist, including rattlesnakes and members of the democraticunderground.
It is best to not tamper too much with nature, because in the end, nature wins out. (Please notice the qualifying phrase, "too much," which gives allowance for some tampering.)
As for the deer, sir, this is a real quandary.....especially for the "animal rights" activists, who stubbornly resist hunting. One would think that as the human population in an area increased, that the animal population would decrease, but that appears to not be the case in Nebraska, where there are six times more deer today, than there were in 1890.
As you can imagine, "animal rights" activists are not popular in this neck of the woods, er, stretch of prairie. I myself regard them with as much esteem as I do the loathesome members of the democraticunderground.
But really, it is a complicated issue, sir; given our experience (here in Nebraska) with the near-extinction of the bison, one of the most noble creatures that ever graced these plains. There were once hundreds of millions of them, depleted to less than 400 by 1910.
The bison have been brought back from near-death; there are a few million of them now (although some are removed from the hospitable terrain of Nebraska)--but it was a close call, and I think many here are somewhat leery of driving any species into extinction, even if rattlesnakes, deer, and Democrats.