GILMER, Texas — Broad areas of grazing land at Pete Gipson’s farm have plow-like scars. But it wasn’t an out-of-control mechanical device that left disjointed ruts and holes.
Gipson and other ranchers and farmers in the South are tormented by herds of voracious feral hogs. The beasts, up to 3 feet tall and 400 pounds, devour feed intended for livestock and tear up pastures in their incessant search for food.
The hogs show little respect for such barriers as barbed wire fences, which merely serve as backscratchers for their hairy, leathery hides.
‘‘They got in that yard a couple weeks ago and cultivated it,’’ said Gipson, 67, as his pickup truck bounced across a once-smooth pasture at his 300-acre Red Cap Farms. ‘‘I smoothed it out and I’ll be damned if they didn’t come back the next night and cultivate it again.’’
In Texas, the wild pig population — now topping 2 million — is exploding thanks to high reproductive rates and few natural predators.
The Texas AgriLife Extension Service estimates the hogs cause $50 million in damage each year.
A solution to the pig problem might come from a lab at Texas A&M University, where a team of researchers is testing an oral contraceptive for the hogs and other pests. It may even become applicable for pets like cats and dogs.
The contraceptive, called a phosphodiesterase 3 inhibitor and in development for about a year and a half, is now in a capsule form and has been fed to captive pigs at the university’s research facility. It prevents the females’ eggs from maturing.
‘‘It does appear to be effective,’’ said Duane Kraemer, a professor of veterinary physiology and pharmacology who heads the research team.
‘‘The animals can continue to cycle and breed. Their behaviors are the same, except they don’t get pregnant.’’
Still, Kraemer cautions, the ‘‘development of an oral contraceptive for an animal that people eat and is to be released into the environment is a complex issue, no question about it.’’
The hogs are descendants of animals introduced more than 300 years ago by Spanish explorers, domestic hogs that have escaped over the years and survivors of Russian boars brought to Texas in the 1930s as exotic hunting game.
After generations of crossbreeding in the wild, the hogs have evolved into fierce survivors that typically travel in herds known as sounds.
The hogs have keen senses of smell and hearing and sharp, continuously growing tusks — two on top and two on the bottom — all the makings of imposing physical specimens.
Gipson said his son-in-law recently was inspecting some land on foot when he was confronted by several of the animals, which leave the shelter of creek bottoms to do their foraging after dark. Outweighed and outnumbered, his son-in-law climbed a tree to safety until they left, Gipson said.
‘‘You might shoot one, but you’d have the rest of them on you,’’ he said.
There is no closed season on hunting the pigs, and in Texas all you need is a regular hunting license. But it might take more than a shotgun to bring down a big hog.
‘‘Just cleans the dirt off them,’’ said Jake Williams, Gipson’s farmhand.
Earlier this month, the Texas Department of Agriculture announced it had awarded the extension service $1 million to provide technical help to landowners under siege from the beasts.
‘‘They eat most anything,’’ Kraemer said. ‘‘One of the reasons there’s concern is they eat eggs of birds that nest in the ground, little deer if they can catch them, sheep and goats. And, of course, they dig for grubs and worms and roots and in the process of doing so, they tear up crops, pastures and make such a mess you can hardly drive on these pastures. It’s just terrible.’’
He estimates it could be three to five years before the birth-control pill for pigs is readily available. The next step in the research is to test the contraceptive outside the lab.
Among hurdles yet to be overcome are how to ensure that the drug is administered only to wild hogs and won’t cause any environmental damage.
‘‘It’s got to be effective, it’s got to be specific, it’s got to be acceptable to meat consumed by humans,’’ Kraemer said. ‘‘And it’s got to be environmentally safe.’’