Predators need a larger range than their prey. To control them via natural predators, we'd have to get back to the human population of 1860, somewhere around 40 million versus over 310 million. The trouble is finding 270 million volunteers to leave! Heck, Arizona's population has added over 1 million/decade for the last 50 years. I remember - and MISS - the Arizona of 1975 - about 2.2 million versus over 7 million today. Not sure where I can find 5 million Arizonans who want to leave.
In the Manti Mountains of Utah, predators have made a comeback. When I worked there in 1980, there were no bears and only rumors of a cougar somewhere. Now they have a number of both. A friend lost more sheep to bears than to coyotes recently, and had a couple of horses jumped by a cougar.
But in truth? A 30-06 is a more humane killer than a cougar, and we can control how many hunters are allowed year by year. We have managed deer, elk and antelope for a LONG time with hunting permits. I don't see why horses are too special to be managed like any other form of wildlife. If they are WILD horses, lets manage them like WILD life.
If people want to hunt horse the same way as elk, deer, moose or any other wild game for that matter, I would be all over that. With permits, regulations so they are not over hunted and these regulations enforced. I guess it would have to be figured out how to determine my best riding horse Snowball from a wild animal. There are many people out there who wouldn't care about the difference. And of course there would be the poachers.
As it stands right now, there are hunting seasons that correlate with the breeding and birthing seasons of wild game. Being as horses gestation period is 11 months, it would probably be hard to not hunt down a pregnant mare unless mares were off limits.
What I am not for is the governments botched job of supposedly being these animals stewards. We are all well aware that what they are doing is not working. Still, I don't think that sending them to slaughter is the answer. It's not that they would be killed and eaten that bothers me. It's the process that bothers me. Animals that are sent to slaughter are being handled by people who could care less about anything other than their bottom dollar which directly leads to the animals mass suffering. The 30-06 doesn't bother me. The starvation, dehydration, stress, fatigue to the point that they are falling down, and abusive handling bothers me.
I also believe that if laws were set to allow the government to legally sell wild horses to people who would in turn sell for slaughter, they would just turn into another money making machine until they become no more. I say 'legally sell' because this is happening already with a blind eye to what is going on. Our government is breaking it's own laws but don't let you or I go out and shoot one to feed our family or catch one to use as a riding horse unless you would like to go to jail and pay hefty fines.
As far as any horses being called domestic animals, I disagree. In one generation of no handling by humans and you have a wild animal. Same thing with cats that we call domestic. Both of these species have not changed very much, especially their brains and how they operate. Dogs on the other hand, who humans have changed dramatically, I would call domestic.
As far as shooting a horse being more humane than being killed by a cougar, I don't really care. That is nature and if the horses are going to be left wild then that is part of it just like any other wild animal. The bottom line is that we started the problem of over population long before these animals were protected by eliminating so many predators.