It’s no secret that the biggest driver of the feral hog problem in the United States is people who trap and relocate live pigs for money or hunting opportunity. Now we have a roadmap of wild pig distribution, and it’s far worse than anything I imagined. Forget about Cletus and Earl hauling a pineywoods rooter across the creek in the bed of a pickup. We’re talking about interstate commerce involving a lot of pigs, and much of it is illegal.
This is another piece of news I picked up at the recent International Wild Pig Conference, where I listened to a presentation by Dr. Timothy Smyser describing the collaborative efforts between the USDA’s National Wildlife Research Center and National Feral Swine Damage Management Program to develop a Feral Swine Genetic Archive.
Feral Hogs on Wheels
According to Dr. Smyser, since 2014 USDA-APHIS has sampled the genetics of more than 23,000 wild pigs. Another 2,500 to 3,000 pigs removed in USDA hog control operations are added to the archive annually. Researchers have identified 14,284 genotypes of feral swine and their geographic origins. They can look at a pig’s DNA and name its place of birth within a 12-mile margin of error. That’s how they produced this map showing the geographic origin points of all the pigs identified as having been translocated:
According to the researchers, 18.6% of all wild pigs sampled in the United States had been translocated in their lifetimes! This information makes one thing clear: Many wild pigs were moving at 70 mph when they exploded across the map of the United States in recent decades.
“When investigating the distribution of all predicted origins, the majority of translocations originated from coastal Georgia, Florida, the border between Oklahoma and Texas, and south-central Texas,” said the authors. “However, if we focus on only long-distance translocations (greater than 1,000 km from sampling location), central and northern Texas as well as Florida are the main sources of translocations.”
In many states where feral hogs appeared recently, all of them arrived on wheels and not through natural movement. Every pig the USDA sampled in Iowa, Maine, Michigan, Minnesota, Nevada, New York, Utah, Washington and West Virginia was identified as a translocated animal. In six other states, a very high percentage of feral hogs were translocated: Arizona (71%), Illinois (95%), Kentucky (77%), New Mexico (77%), Pennsylvania (81%), and Virginia (88%).
Where are the wild pigs coming from? The amazing heat-maps produced from the data show South Texas as the biggest supplier of pigs transported more than 1,000 kilometers (621 miles) from their birthplace. Researchers found Texas pigs now living in 26 out of 38 states they investigated.
The diagram below shows translocations between states. The size of each state’s circle represents the relative number of pigs transported out of that state.
In many states, it is illegal to transport live feral hogs without a permit, or at all. In Texas, it is legal to transport live feral hogs to an approved processing facility within the state. Male pigs can also be transported to and released into an “authorized hunting preserve.” These transport rules are regulated and enforced by the Texas Animal Health Commission, not by Texas Parks & Wildlife. Though leaving Texas with live feral hogs brings other states’ laws into play, genetic evidence shows there are still plenty of outbound pigs.
Not all transported pigs are traveling north. Notice in the diagram above that Saskatchewan and Alberta exported Canadian bacon south into the United States. The researchers found three pigs in Michigan, one in Ohio and seven in Tennessee that originated in Canada.
According to NDA’s 2026 Deer Report, transportation of live feral hogs within state is allowed by 16 states, and 11 states allow importation of live feral hogs. Many of these situations are covered by permitting or release requirements. Rarely is it legal to move pigs and release them into the wild in a new location, especially after crossing state lines. This study shows the need to strengthen laws prohibiting the movement of live feral hogs, and to enforce those that exist.
There is evidence that increased enforcement works. For example, Dr. Smyser reported the percentage of translocated pigs sampled in Missouri has trended downward from 13 to 9% as the Missouri Department of Conservation has increased enforcement and control efforts.
Swine Disease Concerns
One of USDA’s primary concerns is movement of swine diseases that could severely impact domestic swine and commercial pork production. For example, African swine fever could devastate domestic pigs, and it has now been found as close as the Caribbean islands of Haiti and the Dominican Republic. Illegal movements of feral hogs from the South to the Midwest could introduce this swine disease into major pork producing states.
Of course, wild pigs in the United States already carry a number of diseases, such as brucellosis and pseudorabies, some of which can infect humans. Bottom line, the illegal movement of feral hogs is a threat in more ways than just habitat damage and wildlife competition.
Squeal On Pigs
One of the ways hunters and deer habitat managers can help fight illegal feral hog movements is to immediately report sightings of hogs in new areas – and there’s an app for that!
What began as a project of multiple wildlife agencies along the U.S./Canada border is now a much larger international project involving the USDA, the University of Georgia’s Center for Invasive Species & Ecosystem Health, and other partners. The centerpiece is the Squeal on Pigs app, which allows the public to report sightings of feral swine.
Outside the core pig states, detecting an isolated or newly established population allows for quick eradication and prevention of larger problems, so public involvement is key. If you see or hear about wild pigs in an area that isn’t known to be infested, use Squeal On Pigs to report the information quickly.
This is my second report in a series from the International Wild Pig Conference. Read the first one here, and join NDA’s mailing list to receive the others as they are published.