You're on the right track - predators shouldnt be tolerated. It is either you or them, in the real world. Here's an observation from our good friend, Bob Plamondon:
Predators are smart and observant. I rarely hear people mention this, but predators are smarter and more observant than people give them credit for. Now that I've killed two of the crowsthat had been preying on my eggs, at least a hundred are avoiding my farm. I've seen the same effect with four-footed predators: when the farmers and the trappers dispatch livestock-eaters, the predators not only get the message, they pass it on to their young, and a balance is struck.
Practically all the predators are eating wildlife rather than livestock, and this means that both predators and livestock get to have a normal lifespan.
But if you don't kill any predators, their caution fades. After a couple of generations, the mothers stop teaching farm-avoidance to their young, and then the clueless young predators kill a lot of livestock before inevitably being killed themselves. Which is a bad deal all around.
To misquote the song, "Mamas, don't let your babies grow up to be livestock eaters!"
The only other deterrent, aside from dispatch that has any lasting effect is electric fencing.
