Well, random poisoning isn't very ethical. I've used poison quite a bit before, and it has it's place. Here in Texas, it's HIGHLY regulated, for obvious reasons..... It is required to have a pesticide applicators liscense just to buy it. Typically, the poisons are used in feedlots for birds and around grain mills for rodents. Baiting hogs with meat is, perhaps, a good tactic, if you care to get rid of coyotes, too, but you have to limit what can get ahold of it. Tossing it out of heli isn't responsible, IMO.
As for the cost of damage, figure $9.50 (a bit lower than it was a few back when I actually could have sold the crop) per 100lbs. A 150 acre field would have, in my estimate, produced in the area of 5,000lbs per acre...... That's one field.... Figure a 20% loss on 6300 acres of wheat... the crop sold for $7.15 a bushel, producing $1.4m, averaging 32 bushels per acres.... that average would have been closer to 40bu acre if the hogs hadn't been in it..... Then figure the damage to equipment..... I had one combine that broke a hydrostatic drive when it hit a friggin' crater some big sow dug.... That was $1500 plus my time down and labor to install!! And don't forget this is in a 6 month period, within the same year.... Drought has forced us to forgo planting a lot of our acreage, and the risk of hog damage forces us to rotate it in Cotton and wheat, which is not a bad crop, itself, but the risks expand without the ability to diversify.....
Electric fence is not effective. Hunting, baiting, and trapping are the only effective means of reduction of numbers and prevention of damage. Unfortunately, we stay too busy working and often don't have the time to do what we need. And despite the income, don't forget the exorbitant costs of operations... diesel, fertilizer, labor, parts..... To average 10% income is fantastic.... we usually do closer to 5%.... I've had a large number of people, family and friends, help shoot the boogers, and that only works until the next pack moves in and starts raising.... and in some places, once you kill one or two, they just move to the neighbor a few miles, and rebuild their army.... If that neighbor doesn't do much, they are a breeding ground, and the constant overflow is what we kill.
They are an epidemic, spreading to the very suburbs of our cities.... Every time I go South to the Austin or Houston area, I'll see a huge hog run over on the road..... a short ways down the road, I'll see a car with the front end wiped out!! There is little other way I know to deal with it, except treat like an invading army.... Kill them all, in whatever way, with whatever means necessary.....