Wild Hogs Advance North, Threatening Birds, Crops and Pork Production

Texas is infested with wild hogs, as are Louisiana and Florida, and now an ever-expanding population is sweeping south to north, wreaking havoc in states like Oregon, Wisconsin and Missouri. Wild hogs are smart, athletic and elusive, which makes them an exciting prey for hunters, who truck hogs in from out of state for the chance to go at them on their own turf. But once introduced, hog numbers explode; for conservationists, farmers, and pork producers, the animals are a nightmare.

“Once they get to rooting around, anything in their path is going to get destroyed,” said Jim Braithwait, of the Missouri Department of Conservation (MDC). That could mean a row of corn, a hayfield or a hollow visited by pheasants and quail.

A wild hog in Missouri. Between 1988 and 2005 wild hog numbers in the U.S. quadrupled, from one million to four million. (Courtesy of Missouri Department of Conservation)

Practically everything a hog does is destructive. They lack sweat glands and cool off by sloshing around in springs, seeps and streams, causing erosion and sedimentation. Hogs rub mud and parasites from their skin by scratching against, and sometimes damaging, fence posts and trees, and they feed by rooting through the soil in search of mushrooms, acorns and earthworms, plowing trenches half a foot deep.

Braithwait first noted their mark in a clover hay field. “I couldn’t believe how much damage was done by those hogs,” he said, “there was no way you were gonna get equipment in there to cut that hay after those hogs had been through.”

Hernando de Soto brought swine from Spain to Florida in 1539. Settlers let these domestic pigs roam free, and some remained in the wild. Wild hogs didn’t become a nuisance until the beginning of the 20th century, when hunters imported Eurasian boars. These beasts were fiercer than the swine de Soto introduced. They interbred with escaped and neglected domestic hogs to produce the wild hogs causing trouble today.

With few natural predators in states like Missouri, hog populations rise unchecked. Adult sows can wean 10-12 piglets a year and MDC estimates that 70-75 percent of the hogs must be eliminated annually just to keep the population stable. A 1988 map from the U.S. Department of Agriculture (USDA) shows wild hogs concentrated in southern Appalachia, Texas and Louisiana. A 2005 USDA map shows hogs as far north as Oregon, Wisconsin and New Hampshire. Hog numbers in that time have quadrupled, from one million to four million. In Wisconsin, a man unloaded 31 hogs into the woods near Gays Mills in 2002; wild hogs now inhabit 33 Wisconsin counties.

Wild hog damage in a Missouri hay field. “Once they get to rooting around, anything in their path is going to get destroyed,” said Jim Braithwait, of the Missouri Department of Conservation (MDC). (Courtesy of MDC)

No one in Missouri is more worried about wild hogs than the state’s 1,900 pork producers, who generate $1.1 billion annually and hold three million head of swine. Hogs carry over 30 diseases and 37 parasites, according to an MDC video. Most notable are brucellosis and pseudorabies, which weaken hogs and cause stillbirths in sows. If just two domestic pigs test positive for either disease a farm loses their USDA certification and thus their ability to ship product out of state. Brucellosis has been reported in wild hog populations in at least 14 States; domestic hogs in Missouri have yet to contract the disease and industry experts are working hard to keep it that way.

“For our producers, pork pays the grocery bill, the heat and everything else,” said Don Nikodim, Executive Director of the Missouri Pork Association. “We’re very much supportive of efforts to get feral pigs eliminated.”

That means relying on hunters, the group responsible for the problem in the first place. The state is so eager to cull the wild hog population that, outside of deer and turkey season, they have removed restrictions on weapon caliber. Bait, dogs and spotlights are permitted too.

And what’s done with the beasts once they’re bagged?

“They make a good meat,” said Braithwait.