Wild ‘super pigs’ are rooting toward Minnesota. The state wants to keep them out.
Experts say once a feral swine population is established, it’s nearly impossible to remove.
A feral swine sounder causing erosion by using a wallow on Havasu National Wildlife Refuge property. Removal of these invasive feral swine supports the refuge’s mission of conservation and recovery of native wildlife. U.S. Fish Wildlife Service photo
This story was originally published by Investigate Midwest.
Minnesota has long enjoyed its status as a state free of wild pigs, avoiding the billions of dollars of damages suffered each year by other states from invasive feral swine.
Now, Canadian “super pigs” are threatening the state, and pork producers and regulators are concerned about the destruction and disease the animals could bring if they were to establish a population in Minnesota.
Minnesota is the second-largest pork producing state in the country, generating more than $7 billion in economic activity, according to the Minnesota Pork Producers Association.
In the Canadian province of Manitoba, researchers have detected pigs roaming within 40 miles of the Minnesota border.
The Minnesota Department of Natural resources has no dedicated funding for wild pig removal and monitoring programs, and the amount of federal money dedicated to preventing the spread of feral hogs in Minnesota has decreased from $68,000 in 2017 to $25,000 in the current fiscal year.
Populations of feral swine have long occupied territory in the western and southern United States, but have expanded their reach in recent decades. In 1982, 544 counties in the southern U.S. reported established feral swine populations. By 2020, hogs lived in more than 1,900 counties in 35 states.
Wild pigs have never established a colony in Minnesota, but nearby states haven’t been so lucky. According to 2022 data from the U.S. Department of Agriculture, wild pigs were living in areas of North Dakota, Indiana, Kansas, Missouri and Michigan.
Estimates of the feral swine population of the United States vary, but the USDA approximates the current number of animals to be at least 6 million and “rapidly expanding.”
Researchers at Enetwild, a project funded by the European Food Safety Authority, wrote in 2018 that getting accurate counts of wild boar is only feasible in small habitats, in part because the traditional methods of counting animal populations — direct observation — is difficult with nocturnal animals, like wild pigs.
The USDA Animal and Plant Health Inspection Service estimates that feral hogs cause up to $2.5 billion in damages nationwide per year. The animals consume crops, destroy fencing, transmit diseases and parasites and contaminate bodies of water by wallowing and defecating.
Feral hogs are capable of contracting and spreading all of the diseases of domestic swine, including African swine fever, influenza viruses and pseudorabies.
Once feral pigs take over a territory, it’s nearly impossible to eradicate them, said Eric Nelson, wildlife damage program supervisor at the Minnesota Department of Natural Resources.
Feral pigs are intelligent, adaptable, eat a wide variety of foods and have no natural predators besides humans.
“We have a lot to lose if we get feral swine established here,” Nelson said.
Swine are not native to North America. European settlers brought the first pigs to the continent in the 1500s. Later, hunters released Eurasian boars for sport, creating the hybrid population of wild pigs that roam the U.S. today.
Canada didn’t have a significant domestic swine population until the 1980s, according to Ryan Brook, a professor at the University of Saskatchewan College of Agriculture and Bioresources and a leading expert on Canada’s feral hog issue. In order to produce bigger, longer animals, farmers bred domestic pigs with boars to create a hybrid.
“These animals got all the benefits of the wild boar side, especially that fur and the extra long legs and the long snout, and so they got that warmth advantage,” Brook said. “Then they got this huge advantage of being big, which is really important in cold environments to stay warm and survive.”
These hybrids established populations in the wild in the early 2000s. In some cases, farmers released them from fences due to economic hardship during Canada’s droughts of 2001 and 2002.
The wild pigs have even learned to burrow in the snow and line their tunnels with cattails for insulation, Brook said.
Brook runs the Canadian Wild Pig Research Project, which studies the ecology and distribution of wild pigs.
In 2002, Brook and his team recorded zero wild pig sightings in Canada. Then, the population took off. Brook’s team has logged nearly 60,000 wild pig sightings over the past two decades in three Canadian provinces: Alberta, Saskatchewan and Manitoba.
The actual number of wild pigs is difficult to estimate due to the wide geographic distribution, low population density and lack of resources available to researchers, Brook said.
A female pig can have two litters of six offspring per year, Brook said, quickly turning a small population into an unmanageable one.
“There is a very legitimate risk and concern about them coming straight into Minnesota,” Brook said.
Funding drops for Minnesota wild pig removal efforts
The Minnesota Department of Natural Resources does not receive any funding for the prevention or removal of loose or feral pigs, Nelson said.
The only funds dedicated to removing loose swine in the state come from USDA’s Animal and Plant Health Inspection Service Wildlife Services.
From 2017 to 2022, the Department of Natural Resources received 66 feral swine reports. All were related to escaped or released domestic pigs.
The Minnesota DNR resolves many of the calls by tracking down the landowner or owner of the loose animals and ensuring the pigs are returned to their enclosures.
When the owner can’t be identified, and when it’s clear that the animals are living in the wild, DNR calls in Wildlife Services, the department with the tools and the training to safely and quickly capture or kill the animals, Nelson said.
Funding for the National Feral Swine Damage Management Program is based on a state’s wild pig population. The budget for Wildlife Services’ feral swine program in Minnesota has decreased from $68,000 in 2017 to $25,000 in the current fiscal year.
Minnesota director of Wildlife Services Gary Nohrenberg said at the current rate of wild pig incidents, his department can handle the workload at the lower funding level.
But “it can get expensive in a hurry” if staff from his St. Paul office have to drive up to the rural northwest part of the state to respond to calls, Nohrenberg said.
Pork producers fear disease risk
A bill introduced in the Minnesota House of Representatives is drawing some attention to the issue. House File 2387 would make it illegal to possess Eurasian wild boars in captivity. Currently, possession of wild boars for commercial purposes, like hunting, is only allowed with a permit from the Minnesota Department of Agriculture.
It also would require the Minnesota DNR to prepare a report for the legislature outlining recommendations for management of feral swine.
The Minnesota Pork Producers Association testified in support of the bill.
Lauren Servick, director of marketing and public policy engagement for MPPA, said pork producers’ main concern is the risk of disease associated with wild pigs, especially African swine fever.
African swine fever is a highly contagious and deadly disease in pigs. Farmers can lose entire herds to the disease, and countries often pause imports from areas where the disease has been detected.
There is no treatment or vaccine for African swine fever, and the only way to stop the spread of the disease is by depopulation — killing of entire herds. It has never been detected in the United States.
“It could be a really dangerous situation if there were feral pigs in Minnesota that could contract this virus and then inevitably spread it,” Servick said.
JBS, the world’s second-largest pork company, operates a large pork processing plant in southwest Minnesota. The company did not respond to a request for comment about how an influx of feral hogs would affect its business.
Once established, wild pigs are tough to eliminate
Nelson said preventative efforts and removal of all swine living in the wild is important because pigs are quick to adapt. Even recently escaped domestic pigs can adapt to living in the wild in a matter of days.
“You’ve got to credit how smart they are,” Nelson said. “Look at the invasive species and how much they’ve expanded no matter what.”
In several states with large established feral swine populations, hog hunting is largely unrestricted. In Texas, home to at least 2.6 million feral hogs, helicopter hunting is a popular method of killing feral hogs.
But experts warn that hunting can have the opposite of the intended effect. Wild pigs quickly pick up on hunting methods and become harder to catch or kill, Nelson said. Hunting also incentivises the transport and release of feral hogs, he said.
In Minnesota, it’s illegal to shoot wild hogs, unless the incident is reported to authorities within 24 hours.
In Canada, hogs now cover more than 650,000 square miles of territory.
“In 20 years, we went from a non-problem to an out-of-control freight train,” Brook said.
Our stories may be republished online or in print under Creative Commons license CC BY-NC-ND 4.0. We ask that you edit only for style or to shorten, provide proper attribution and link to our web site. Please see our republishing guidelines for use of photos and graphics.