South Carolina has a pig problem.
Feral pigs have destroyed crops and consumed natural resources needed by other wildlife for more than half a century. Hunters, farmers and the S.C. Department of Natural Resources have been struggling to reduce the pig population for about three decades.
The failure to control the growing population has come at a cost.
According to a recent Clemson University study, wild hogs cause $115 million per year of ecological damage in South Carolina — that’s $44 million in damage to crops, livestock and timber and roughly $71 million in non-crop losses from damage to streams, ponds, wetlands, landscaping, vehicles, fire lanes, unpaved roads and wildlife food plots.
This is the first time hog damage has been assessed in South Carolina.
Earlier this year, Clemson University wildlife biologist Shari Rodriguez surveyed 2,500 farmers and rural members of the S.C. Farm Bureau to understand their perceptions of wild hogs and the cost of damage caused by the invasive species, a term that applies since pigs aren’t native to the Americas.
The survey asked landowners about issues they are having with wild hogs, the techniques they currently use to control hog populations and whether they see wild hogs as a benefit or a nuisance to their land.
Rodriguez received about 750 survey responses and then compiled and analyzed the data and submitted a report to the U.S. Department of Agriculture in March. The new report estimates perceived damages based on survey responses but does not report actual damages. However, it provides crucial management insights.
“Feral hogs and the damage they cause are a huge and growing problem in South Carolina and across the Southeast, and this survey is the first step in understanding the complexity of the problem and designing strategies to control their populations and reduce their impact,” Rodriguez said.
She added that wild hogs are “ecological zombies,” eating livestock and other animals, including deer fawn, endangered salamanders and ground-nesting birds and their eggs. Wild hogs also use their snouts to dig in dirt and mud to consume agricultural crops, seeds, sprouts and seedlings.
That can disrupt reforestation. For example, the wild hogs are threatening efforts to re-establish long-leaf pine forests at Congaree National Park. The hogs eat the pinecones that carry seeds, which are vital for future tree growth, according to Liz Struhar, Congaree National Park’s chief of resource management.
Wild hogs also root, wallow and nest in the ground, which can decrease water quality and promote soil erosion. They also threaten human health, as they can be aggressive toward farmers, park visitors and hunters, officials say. But the biggest health concern is their ability to carry diseases, such as brucellosis, which is a fatal to livestock and other animals. It can cause fever in people.
“It is shocking how many diseases they carry,” Rodriguez said. “They are vectors for a lot of diseases that can be passed on to livestock or other wild animals, too. It’s best to wear gloves when handling them.”
Hog haven since the 1500s
An estimated 130,000 to 140,000 wild hogs live in South Carolina, an increase of around 30 percent over the past decade, said Charles Ruth, wildlife biologist with the S.C. Department of Natural Resources.
Wild hogs have been present in South Carolina since the Colonial period, according to Ruth. European settlers first brought domesticated pigs to the Americas in the 1500s, but some eventually wandered off and thrived in the wild.
In 1890, sports hunters released wild European boars in the U.S. Those boars mated with the feral pigs, which led to the type of species now seen around the Carolinas. In the mid 1900s, people across the country started stocking wild hogs and hunting them as big game animals, according to Jack Mayer, manager of environmental sciences and biotechnology at the Savannah River National Laboratory.
Wild hogs were once limited to the coastal regions of South Carolina but expanded to the Piedmont region in the 1990s when people started transporting and releasing hogs for hunting, according to Ruth.
Wild hogs are now present in all 46 counties, spreading to new areas as people continue to catch, transport and release them for hunting, according to Marion Barnes, a senior agent with the Clemson University Cooperative Extension Service.
“In addition to the tremendous amount of damage they are causing crops and timber, they are also turning up in urban and suburban neighborhoods throughout South Carolina and the Southeast,” she said.
Upstate counties have struggled with wild hogs in residential areas. Last year, Anderson County received an increasing number of residential complaints and partnered with the South Carolina Wild Hog Task Force and U.S. Department of Agriculture to hold educational seminars for the public.
Shortly after, the USDA allocated federal money to State Wildlife Services to be used to expand their campaign against wild hogs in the county, which currently has one of the largest wild hog populations in the state.
In the crosshairs
The state has waged war against wild hogs for years.
In 2005, the state decided that residents couldn’t release hogs into the wild. The state then ruled that hogs couldn’t be removed from the wild without a $50 permit issued by SCDNR, according to Ruth.
More recently, the state revised night hunting laws to allow hogs, coyotes and armadillos to be hunted year-round on private land at night with lights and night vision, with certain weapons restrictions.
However, a second law change set up a “night hunting season,” which runs from the last day of February to the first day of July. Interested residents must register their land with SCDNR. But once registered, residents can hunt pigs on the registered land with no restrictions, according to Ruth.
Farms are using hunters to eliminate hogs and save their crops.
Allendale County farmer Mark Connelly plants various crops, including corn, on 13,000 acres near Ulmer and has struggled with the growing pig population. “It’s a yearly battle,” Connelly said. “One year I planted 93 acres of corn on a Saturday. By Wednesday night, the hogs had covered the whole field.”
“I have a guy with a night vision scope. He hunts from January to May and I pay him $25 per head. He’s killed as many as 300 hogs on my land alone, and he works on other farms around here as well,” he added.
However, Rodriguez’s survey shows that respondents reported very little investment in hog control, such as trapping or fencing. “Fencing is not practical. It’s cost-prohibitive,” said Colleton County farmer Randy Ulmer.
Hog-proof fencing is expensive, costing up to $50,000 per mile. In addition, the annual maintenance of the fencing can cost up to $2,000 per mile. Also, hog-proof fencing is typically used for small applications.
Ulmer, who farms corn and peanuts, has turned to trapping. Wild hogs continue to create large piles of dirt that are impassable for farm equipment and often require field repairs, he said. Ulmer once trapped 22 wild hogs in one trap, but trapping has been less successful this year because hogs have had a stable food supply.
He added that the hogs have been eating rotten peanuts that couldn’t be harvested following the historic flood last October.
“They need to be eradicated, not just controlled,” said Barnes. “They’re a nuisance wildlife, and they need to be treated as such. I deal with the destructive nature of them day after day when I visit farms and see what they do to corn crops and peanut crops. I’ve got nothing good to say about feral hogs.”
Stopping the cycle
SCDNR, Clemson University and the USDA continue to hold seminars across the state to teach farmers and the general public about wild hogs and effective removal methods, according to Ruth.
Gary Spires, director of government relations at the S.C. Farm Bureau, said members have benefitted from the seminars. “Those have absolutely helped. We’ve had farmers take what they learn, implement some traps and help control the spread of hogs,” he said. “The challenge is that hogs are so prolific. They replace what you trap each year.”
Wilds hogs adapt to trapping methods. “If you don’t remove the entire population in that sounder [herd], you’ve just educated the hogs that didn’t get trapped. Once you’ve failed to catch the whole sounder in a particular trap setup, you’d better switch the trap setup if you hope to capture the rest,” she said.
Trapping and euthanasia is the conventional method of management, but there is debate about which baits, trap designs and strategies are most effective. The USDA traps and kills about 1,000 hogs annually for landowners and government wildlife preserves in South Carolina, according to Noel Myers, state director with the USDA’s wildlife services division.
The agency currently uses enclosures that can be shut remotely by hog trappers. Cameras show officials when wild hogs walk into an area to eat corn or other bait, and once the hogs enter the enclosure, an official closes the door with a simple command from a cellphone, Myers said.
The Department of Agriculture is currently trapping and killing wild hogs at Congaree National Park, where the growing wild hog population is threatening visitors and long-leaf pine reforestation efforts.
According to the park’s management plan, wild hogs have lived in the Congaree flood plain for 200 years, but the population increased at the national park after hunting was banned in 1982. Officials don’t know how many wild hogs live in the 27,000-acre woodland and flood plain.
The National Park Service struggled to reduce the hog population for decades, according to Struhar. So the park recruited the help of the USDA last year. Since then, federal officials have killed more than 100 wild hogs.
However, officials are unsure if the trap and kill program will reduce the park’s growing hog population. Hunters must kill 75 percent of the population every year for nine years, according to Mayer. Hunters currently kill roughly 30,000 hogs in South Carolina each year, but that isn’t enough to stop the increasing population.
Wild hogs can begin breeding at just six months old and remain fertile for about 10 years. Sows can reproduce three times a year and give birth to an average litter of one to 13 piglets. “Those biological characteristics contribute to the knowledge that their population is going to grow exponentially,” Rodriguez said.
Scientists are developing oral contraceptives and pig-specific toxins to help prevent wild hogs from reproducing, according to Mayer. However, the impacts on other animals and humans haven’t been studied.
Until then, Rodriguez said a comprehensive study on the actual damages from wild hogs would be beneficial. “Our hope is to continue on with this line of research and expand it with future grants from government agencies that will help us look at the broader scope of the Southeast with regards to hogs and hog damage,” she said.
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