Six million untamed swine roam the expanse of the United States. Possessing heightened intellect, considerable stature, edibility, and reproductive prowess, they have metamorphosed into a nocturnal specter haunting the collective nightmares of Americans.
| Engaging in Malevolence |
Wild boars, not indigenous to North America, made their incursion in the 16th century. European immigrants and explorers orchestrated the introduction of Eurasian wild boars to the New World, envisioning them as livestock or game. Presently, their hoofprints span across at least 35 states in the United States, comprising a populace of around 6 million. Towering at 1.5 meters in length and weighing over 226 kilograms, these creatures exhibit remarkable adaptability, thriving in almost any conceivable habitat. Their territorial invasion extends from the Caribbean Islands to Mexico to Canada, undeterred even by frigid snow and freezing temperatures.
Exacerbating the predicament, sows demonstrate reproductive acumen as early as eight months, birthing two litters of piglets every 12 to 15 months, with each brood typically numbering between 4 to 12 piglets. This prolific reproductive capacity perpetuates the expansion of their operational domain. Wherever they traverse, they not only lay waste to crops but also inflict harm upon farmers attempting to corral them. Statistics reveal that wild boars annually incur economic losses of up to US$2.5 billion to the U.S. agriculture, forestry, and livestock sectors.
Beyond trampling crops, wild boars also predate upon indigenous wildlife. From the ground-nesting birds of Texas to the imperiled green and loggerhead sea turtle eggs on the South Carolina islands, to the mid-toothed snails and red-cheeked salamanders of the Great Smoky Mountains National Park, all succumb to the depredations of feral hogs. Despite their tasteful appeal, these repercussions are not the foremost concerns of experts.
| Harbingers of Viral Havoc |
As per the USDA, wild boars carry an array of pathogens transmissible to humans, including Leptospira, Toxoplasma gondii, Brucella, swine influenza virus, Salmonella, hepatitis viruses, and pathogenic E. coli. Moreover, they harbor the potential to instigate novel diseases yet to be comprehended.
“Wild pigs serve as a crucible for viruses,” remarks Veenna Brown, a biologist with the U.S. Department of Agriculture’s Wild Boar Damage Management Program. “Susceptible to human viruses, such as influenza, they, upon infection, generate new viral strains. In my estimation, the peril posed by wild boars surpasses that of other wildlife, given their communal living, vast numbers, and proximity to humans.”
Presently, U.S. health officials harbor paramount concerns regarding African swine fever. Though non-communicable to humans, this virus, originating in 1921, proves exceedingly fatal to both wild and domestic pigs. If widespread infections were to ensue in the United States, the entire pork industry would be severely imperiled. In 2021, domestic pigs in Dominica and Haiti fell prey to the virus, marking the closest infections to the United States to date. Brown expresses, “This risk of infection sends tremors through the entire pork industry.”
Scientists have diligently monitored the dissemination of various diseases among wild boars. Managers at the Great Smoky Mountains National Park initiated the surveillance of wild boar health in 1959, unveiling the first case of pseudorabies in 2005. Though this malady does not directly imperil human health, it triggers abortions in sows and fatalities in other creatures such as wild raccoons, opossums, and even domestic cats and dogs. “The virus transmission rate in wild boars fluctuates from essentially zero to 20 to 40 percent, depending on the year,” elucidates William Stiver, director of the Great Smoky Mountains National Park. “One can be assured that the virus is present. We monitor its propagation through wild boars in the park.”
Within national parks, infectious diseases, including leptospirosis, stemming from bacterial origins, pose a formidable threat. The U.S. Centers for Disease Control and Prevention elucidate that if untreated, infections can lead to kidney damage, meningitis, liver failure, respiratory distress, and even death.
Porcine brucellosis, another bacterial-induced ailment, has surfaced in pig herds in the Midwest. Travis Grant, an official with the U.S. Department of Agriculture and wildlife expert, warns of its transmissibility to humans through contact with blood and bodily fluids. While antibiotics can arrest the infection in its early stages, without prompt medical intervention, brucellosis may induce enduring health complications and even fatalities. Hunters and farmers emerge as the groups most susceptible to infection. Grant advocates for the use of rubber gloves and avoidance of fluid exchange when in contact with wild boars.
Between 2007 and 2008, the U.S. Centers for Disease Control and Prevention reported at least three cases of brucellosis infection in the eastern United States following wild boar hunting. Fortuitously, none proved fatal. To date, the transmission rate of viruses between pigs and humans remains relatively low. Nevertheless, as the habitat of wild boars continues to burgeon, this risk is destined to escalate.
| A Counteroffensive |
Traditional hunting methods have proven ineffectual against wild boars. Superintendent Stever of the Great Smoky Mountains asserts that despite the elimination of over 15,000 wild boars since trapping and hunting commenced, their overall population remains almost unaltered. Biologist Brown adds, “In states like Florida, California, Oklahoma, and Texas, the feral pig population is too vast, and their geographical range too extensive… Complete eradication is nearly impossible, with damage management taking precedence.”
Fortunately, glimmers of hope persist in regions where wild boars have yet to attain total dominance. In 2021, wildlife expert Grant led a team to eradicate approximately 10,000 wild boars in Missouri, the northernmost part of the Midwest’s wild boar range, resulting in a 60% reduction in their population. Under Grant’s coordination, 13 federal and state government agencies, along with agricultural and conservation organizations, actively responded to the call for feral pig eradication.
Experts posit that, in the long run, the benefits of controlling the wild boar population far surpass the costs, even if these benefits may not be immediately apparent. Brown emphasizes, “We cannot fathom the repercussions of disease spread, and that is precisely why we must exert every effort to forestall this impending disaster.”