AUSTIN, Tex.

But for the future of civilization as we know it?

More pork. Feral hogs, to be exact.

They’re multiplying like mad — like rabbits with hooves, tusks and an epic sense of entitlement — especially here in Texas, where an estimated 2.6 million of them routinely desecrate farmland by rooting up crops, decimate reptile populations by snacking on them, devour feed meant for livestock and probably do some other pernicious thing beginning in “de-” that won’t come to me right now.

Destroy enclosures! That’s it! Feral hogs have been known to chew and stomp their way into suburban yards and even onto Army bases, said Richard Heilbrun, a biologist with the Texas Parks and Wildlife Department. “And when you have a military installation with a fence problem,” he told me, “you have a national security problem.”

You also have an excellent reason to turn these hammy hellions into dinner.

That’s what the chef Ned Elliott was up to when I dropped by his Austin restaurant, Foreign & Domestic, on Friday. He and several other cooks were using deboned flesh from two feral hogs for porchetta, the beloved Italian roasted pork dish. They planned to serve it, along with giant Asian tiger prawns and Himalayan blackberries, at a special feast at the restaurant staged in cooperation with the Texas chapter of the Nature Conservancy.

The event had a saucy sobriquet, “Malicious but Delicious,” and a serious mission: to raise people’s awareness of, and ideally whet their appetites for, the bullies of the ecosystem, more formally known as invasive species, invasives for short. In certain areas of the United States, the hogs, the prawns and the blackberries qualify.

“They’re aggressive,” Elliott told me, providing a tidy case for their digestion.

All you principled environmentalists out there, you’re being lax. Your recycling is admirable and your farmers’ market patronage appreciated, but there’s a whole class of animals, fish and plants that are throwing the earth out of balance, and it’s time you turned not just your attention but also your bicuspids and incisors toward them.

They aren’t evil in and of themselves. They just don’t play so well with others, and proliferate ostentatiously. Many aren’t even meant to be part of the habitats they now maraud across, but thanks to human meddling, they ended up there, then got bossy about it.

“It’s as if you came home from work and a bunch of people had moved into your house,” said Laura Huffman, the Texas director of the Nature Conservancy. “Maybe they’re nice enough, but they’re still eating all your food and sitting on your furniture, and that’s going to disrupt the way your family lives.”

She was referring not only to hogs and tiger prawns but also to European green crabs, now common in Maine, where they prey on unsuspecting scallops.

Also Asian carp, the thuggish mobsters of the Mississippi, though maybe not for long. There’s been talk of rebranding them as “Kentucky tuna.”

Edible invasives are cataloged on a Web site aptly titled Eat the Invaders. It reflects a slowly growing awareness of the problem and a fledgling effort by ecologically minded chefs to address it.

In New York not long ago, the chef Kerry Heffernan prepared Asian carp and lionfish, which pose a ferocious threat from the Caribbean to the Carolinas, for a dinner at the James Beard House. At Miya’s Sushi in New Haven, Bun Lai regularly promotes such invasives as Asian shore crabs and burdock, a plant whose root is a delicacy in Japan.

And since November, a lionfish appetizer has been a mainstay at the restaurant Haven in Houston. Its chef, Randy Evans, told me that one problem with serving it and other invasives is cost. Absent an established market for them, suppliers are few and supplies expensive.

He said he paid $20.99 a pound for fillets of lionfish, which are absurdly plentiful in the nearby Caribbean, but $17.99 for tuna flown all the way from Hawaii.

Feral hog meat, used at Haven for a “wild boar chili,” is less exorbitant and more available, partly in response to a piggy population explosion sometimes called the “pig bomb.” Across dozens of states, there are about five million feral hogs, descendants of imports from Europe, and Heilbrun said that the fecundity of females, which give birth more than once a year, is the stuff of legend.

“The old joke is that their average litter size is six, but 10 survive,” he told me.

While Texans have accelerated their killing of hogs to about 30 percent of the populationannually, that still allows for a doubling of the population over a five-year period. And that underscores the strange blind spots in the ways of us conscientious omnivores, who congratulate ourselves on foraging and on nose-to-tail eating while failing to chow down adequately on an entire breed just begging to be bacon.

EAST LANSING, Mich. — At first he thought it was a deer, perhaps the big-antlered buck he had seen before and hoped to bag someday.

But the closer Steve Davenport got, the more unfamiliar the looming dark mass in the cornfield behind his house seemed.

At 15 feet, he saw the long, bristled snout. Then he saw the hoof.

“It just kept looking more and more like a pig,” he recalled. “I had never heard of anything like that. I was just kind of in shock.”

In southern states like Texas, backyard encounters with feral swine have become routine. The pigs — ill-tempered eating machines weighing 200 pounds or more — roam city streets, collide with cars, root up cemeteries and provide plot lines for reality TV shows like “Hog Hunters.”

But the pig wars are moving north. In Michigan, New Hampshire, New York, North Dakota, Ohio, Oregon and Pennsylvania — states where not long ago the only pigs were of the “Charlotte’s Web” variety — state officials are scrambling to deal with an invasion of roaming behemoths that rototill fields, dig up lawns, decimate wetlands, kill livestock, spread diseases like pseudo-rabies and, occasionally, attack humans.

In 1990, fewer than two million wild pigs inhabited 20 states, according to John J. Mayer, the manager of the environmental science group at the Savannah River National Laboratory in Aiken, S.C., who tracked the state populations. That number has now risen to six million, with sightings in 47 states and established populations in 38 — “a national explosion of pigs,” as Dr. Mayer put it.

The swine are thought to have spread largely after escaping from private shooting preserves and during illegal transport by hunters across state lines. Experts on invasive species estimate that they are responsible for more than $1.5 billion in annual agricultural damage alone, amounting in 2007 to $300 per pig. The Agriculture Department is so concerned that it has requested an additional $20 million in 2014 for its Wildlife Services program to address the issue.

There is wide agreement that the pigs are undesirable — like the Asian carp that is threatening to invade the Great Lakes, but far bigger, meaner and mounted on four legs. But efforts to eradicate or at least contain them have been hampered by the lack of a national policy to deal with invasive species as a whole, the slowness of states to recognize the problem and the bickering between agencies about who is responsible for dealing with them.

“As a nation, we have not thought through this invasive species problem, and we just have disaster after disaster after disaster,” said Patrick Rusz, the director of wildlife services at the Michigan Wildlife Conservancy. Dr. Rusz, who travels around the state educating farmers about the menace posed by the wild pigs and encouraging them to set traps on their land, is so avid a hog-hater that in the early stages of Michigan’s invasion, he went to bars to eavesdrop on hunters who might have spotted the porcine invaders.

At least in Michigan, Dr. Rusz said, the pigs appear to be winning — their numbers are estimated at 3,000 to 5,000 and growing. Wild pigs are virtual Houdinis, able to dig or climb over almost any barrier; pig experts are fond of saying that “if a fence won’t hold water, it won’t hold a wild pig.”

Allowing hunters to shoot them in the wild all year round, as Michigan and other states do, is not in itself enough to limit the population, Dr. Rusz said. So trapping is an important component of wild pig control, as are bans on owning or breeding the animals.

But state bans like an invasive species order issued by Michigan in 2011, which prohibited ownership of Russian wild boar and other feral swine, have been opposed by shooting preserves and other businesses with a stake in keeping them.

“The conundrum is that you’ve got one of the world’s hundred worst invasive animals, and at the same time you’ve got a highly desirable game species,” Dr. Mayer said. “It’s a real Jekyll and Hyde type situation with wild pigs.”

In the United States, “the pig bomb went off after 1990,” Dr. Mayer said, when Northern states began holding hog hunts, which had long been popular in Southern states. Among other reasons, the pork is tasty, hunters say. In Texas and Florida, most feral swine are descendants of domestic pigs released into the wild or hybrids. Michigan’s wild pigs came primarily from escaped Russian wild boars imported from Canada for hunting on private game ranches.

Political battles over how best to control the pigs can become vicious. In Pennsylvania, the State Game Commission was scheduled to take a final vote this month on a regulation to prohibit private shooting preserves from owning feral swine. The regulation, said Cal DuBrock, the director of the State Bureau of Wildlife Management, was intended to keep the trickle of wild pigs from turning into a deluge.

“All of our counterparts across the nation have said, ‘Nip it in the bud, otherwise it will get away from you,’ ” Dr. DuBrock said.

But state lawmakers, prodded by shooting preserve owners and some hunters, are on theverge of passing legislation redefining the term “wild animal” to exclude wild boar kept behind a fence, effectively removing them from the commission’s purview. The commission is now amending the regulation and will take a final vote in June.

In Michigan, the bruises still hurt from a fierce clash over the state ban that pitted farmers (afraid for their crops) and pork producers (worried about disease) against the owners of about 60 private game ranches that offered wild boar hunts and a few small pig farmers who kept the boars. The fight grew so heated that at one point, the rock musician Ted Nugent, who owns a game ranch near Jackson, jumped into the fray, as did a conservative commentator based in Arizona, Mike Adams, who claimed that the ban meant Michigan regulators would be “kicking in the doors of all these farmers, shooting the pigs and then arresting all of these farmers as felons.”

Boris, the wild boar Mr. Davenport shot behind his house, played a prominent role. His huge head and bristled hide were displayed at legislative hearings on a bill that would have nullified the ban, substituting regulations for fencing and health checks on penned wild boars. (The bill died in the Senate.)

The issue has been complicated here by a state-issued description of the physical characteristics of Russian boar. Just as different breeds of dogs have a common ancestor, all pigs are descended from the wild boar, and all fall under the species sus scrofa. But biologists say that generations of selective breeding have resulted in domestic pigs that look very different from their ancestors.

The differences, Dr. Rusz said, are as clear as those between a pit bull and a poodle.

“It’s simple,” he said. “Russian boar — global track record of destruction, property damage, bankruptcy and spreading disease. Porky Pig on the farm — none.”

But five lawsuits filed by game ranches and small pig farmers have challenged the Michigan invasive species order, in most cases putting forward some version of the argument that a pig behind a fence is by definition a domestic pig.

Meanwhile, the Michigan Department of Natural Resources is suing a shooting preserve, Renegade Ranch, for keeping wild boar after the ban went into force last spring.

Ron McKendrick, the owner of the 300-acre ranch, said that wild boar were cheaper for hunters than the deer and bison he stocks and made up 80 percent to 85 percent of his business, money he would lose if the ban holds. (A court ruling allowed him to keep the boars and offer hunts until the suit is resolved.) “I’m done if I don’t have hog hunts,” he said.

On a recent Friday, a group of hunters pursued a wild boar for several hours on Mr. McKendrick’s ranch, through a pine forest still wrapped in a deep blanket of snow. They eventually shot the animal.

Mr. McKendrick argues that he should not be penalized for the actions of irresponsible ranch owners who have inadequate fencing — a hole in his 10-foot reinforced fence that in one instance allowed some boar to escape was made by vandals, he said.

Dr. Mayer, who consulted with Michigan officials on the ban, said that in battles against invasive species, some people are bound to lose out.

“Unfortunately, this law, which is for the greater good, is going to end up hurting people. There’s no question about that,” he said. “It makes me glad I’m not a politician.”

In May, for example, the police in this hog-producing city arrested four people who had sold dead pigs to slaughterhouses. And in December, a Zhejiang Province court sentenced 17 people to prison sentences, one for life, for processing and selling meat from pigs that had died of various diseases. In less than two years, the group had collected about 77,000 animals.

So, as the authorities have cracked down on people selling diseased or dead pigs, agriculture experts say, it is possible that someone may have decided it was better to dump dead pigs into the river.

If that was the case — and there is no proof right now that it was — a mystery remained: Where did the pigs — 7,545 at last count, with the number still rising — die, and who threw the carcasses into the Huangpu River?

After the pigs began showing up by the thousands in the river last weekend, teams of pitchfork-bearing men fanned out on barges to fish the rotting carcasses out of the water.

With food safety a growing concern in this country, and cities like Shanghai just beginning to enforce new rules that discourage restaurants from using recycled gutter oil, officials moved quickly to assure the public that the city’s water supply met national standards, and that its pork supply was safe.

The city embarked on a major cleanup. Early this week, pig carcasses that had been dragged from the river were buried in deep trenches, and uniformed inspectors lugging suitcases filled with laboratory equipment tested pork samples at outdoor markets throughout the city.

The Ministry of Agriculture announced that it would undertake its own investigation.

One government department suggested that a likely explanation for the deaths was cold weather, even though the Shanghai area rarely gets snow and was in the midst of unusually warm temperatures last week.

The remark provoked ridicule on social networking sites, where some suggested that the comment was as ludicrous as believing that the pigs had engaged in mass suicide.

A more likely cause, porcine circovirus, a disease common among pigs but believed not to be harmful to humans, turned up in samples of the carcasses taken by the Shanghai authorities.

Jiaxing, which sits on the Huangpu River about 70 miles from Shanghai, was an obvious suspect as the source. Those suspicions seemed to be confirmed when Shanghai officials said that more than a dozen of the pigs carried ear tags indicating that they were from Jiaxing. The authorities then announced that they had detained a farmer who confessed to throwing his animals into the river.

But in Jiaxing, farmers denied dumping pigs into the river, calling it preposterous and saying that the animals could not possibly have floated all the way to Shanghai. “If we dumped pigs in the river near here, by the time they arrived in Shanghai, they’d be unrecognizable,” said one farmer, Xu Jinfu.

Another farmer, Xu Jinhua, who was standing outside his pens with a shovel, said, “It feels a little uncomfortable to hear Jiaxing blamed for this.” The farmer continued: “This river flows slowly. Do you think pigs from here would get all the way to Shanghai?”

Xu Jinfu, who helps manage a collective with about 3,000 hogs, said that piglets were often sold to farmers closer to Shanghai to raise, and that that may explain why some ear tags showed Jiaxing. Indeed, in photographs many of the dead pigs appeared to be relatively small.

He also said that Jiaxing had a designated disposal area for pigs that died of sickness.

Several other farmers in Jiaxing insisted that farms in the area had not experienced a high number of deaths or other problems, and that Jiaxing pigs were generally healthy.

“We treat our animals here well. We feed them well,” said another farmer, Zhang Bing, who was pointing to large sacks of animal feed. “In Shanghai, they often just feed them table scraps. Those pigs are more likely to get sick.”

Unscrupulous farm practices, though, are not uncommon in Jiaxing, or in other hog-producing areas.

Cracking down on food safety violations has not been easy. In 2007, the government executed the leader of the country’s Food and Drug Administration for taking bribes from drug makers and failing to adequately protect citizens. The country also announced a nationwide crackdown on illegal food processors.

In Jiaxing, a local official named Huang Hao said one possible explanation was that the pigs had died while being transported to Shanghai, and that the truck drivers had simply dumped them in the river.

On a drive through Jiaxing, with a reporter following in another car, Mr. Huang stopped and pointed at a truck that was preparing a hog shipment. With three levels of cages stuffed with hogs, it was about to embark when Mr. Huang walked over and started pointing.

“Look! See how crowded this cage is? Look at that one, and that one,” he said, pointing to hogs that seemed to be suffering beneath the weight of other hogs. “Some of those pigs will definitely die on the road!”

Three men finished loading the truck and locked the top level.

Not realizing he was a government official, the men largely ignored him and snapped back, “No, it’s safe!”

Then the truck pulled away, and Mr. Huang shrugged his shoulders.

The police have responded to accusations of maltreated pigs. The gaunt backs of his Meishan pigs were normal, the result of their belly fat stretching the skin, he said he told the police, who were initially skeptical. “You ain’t taking them over my dead body,” Mr. Blake said he told the authorities, who, after further investigation, let him be.

There was even a suspected case of poisoning, Mr. Blake said. One morning in the middle of 2009, two men – one tall, one short – showed up in a black truck at a farmstead where Mr. Blake kept his pigs, he said. The family living there thought the men were friends of Mr. Blake’s, and they entered the barn with a black satchel. About a week and a half later,he said, his sows were birthing dead piglets.

At one point, Mr. Blake said, his herd had grown to more than 1,200. But the numbers have since dramatically decreased through sales, samples he gave away and some hitches in the raising process. There was one instance, he said, when an elderly man he had hired to raise the pigs botched a castration, leaving one testicle attached.

Mr. Blake also struggled to finance his operation, which he calls Rustik Rooster Farms. He went to banks, the government, angel investment groups and individuals but could not get anyone to invest. Things became so dire that he had decided to quit one day last summer, only to receive a call the next morning from a producer of the Travel Channel’s “Bizarre Foods,” saying the network wanted to feature him in an episode. The episode was broadcast on Monday, and Mr. Blake said he has been inundated with calls from people across the country wanting pigs and bacon.

Over the past year, Mr. Blake has stepped back from his operation to regroup. He has hired Amish farmers in eastern Iowa to raise his pigs so he can focus on the marketing and sales. Several times a week, with a Rockstar Energy Drink in hand, he slides into a red, rusted 1994 Toyota pickup truck to make the five-hour round-trip journey from his headquarters here to the Amish’s rolling pastures.

By March, he said, he hopes to have about 50 of his Swabians market-ready – he sells them for $3.75 to $4.50 per pound. Within the next seven months, he said, he hopes to have enough pigs to begin selling them weekly. In the meantime, he is supporting himself by selling bacon, beef sticks, novelties like bacon floss and bandages, and roasting pigs for special events.

But Mr. Blake is never quite satisfied. He speaks giddily of the hydroponic chambers (not “hippie hydroponics,” he says) he uses to make barley to feed his pigs, and of a “super pig” he is breeding – one with the tasty qualities of the Swabian, but that can be raised at the speed of commercial pigs. For now, he is not saying much more than that.

“I think we’re on the verge of something,” he said.

the new york times 28 february 2013