Texas has the worst feral hog problem in the United States, according to a recent University of Georgia study at its Center for Invasive Species and Ecosystem Health.

The study showed Texas and other Southern states with the animals reported in 100% of the counties. And the invasive animals have expanded significantly in the past four decades.

They can reach five feet in length, grow to 400 pounds, and run 30 miles per hour. They’re tusked, hairy, sharp-toothed, and aggressive. They’ll eat nearly anything and they have no major natural predators.

Call them feral swine, wild boar, wild hogs, or razorbacks: they are one of the most destructive invasive animal species in the U.S., and they are spreading to more and more of the country as time goes by.

European settlers first brought Sus scrofa — the species that includes both domestic pigs and wild hogs — to what is now the continental U.S. in the 1500s as a food source. As settlers expanded into the U.S., pigs occasionally escaped captivity, where they returned to their wild roots.

Subsequently, in the 1900s, European or Russian boars were introduced to the U.S. for sport hunting. Interbreeding between escaped domestic pigs and boars has created hybrids with the strongest characteristics of each.

Wild hogs have several qualities that have allowed the species to take hold. Allowed to graze freely in the wild, feral swine can grow to larger sizes than domesticated pigs with controlled diets. Attributes like intelligence and a strong sense of smell allow wild hogs to survive well in the wild. Because they do not have substantial predators outside of humans and can live comfortably in a variety of climates, there is little to stop their continued spread.

Perhaps most significantly, wild hogs are very fertile. Each litter of newborn hogs averages around five offspring but can reach as many as 12, and sows can give birth to a litter up to twice per year. In sum, the species’ strength and rapid reproductive rate have led to exponential population growth.

In recent years, the result has been a significantly increased range for feral pigs across the United States. Four decades ago, feral swine had a presence in only 20 states, primarily in the South. Over time, that figure has grown to 36 states as the animal’s range has expanded more westward and northward. And feral pigs’ presence has expanded within states as well. The number of counties affected by wild hogs has nearly tripled since the early 1980s, from 550 in 1982 to 1,496 in 2023.

Wild hogs’ expansion across the U.S. is no mere inconvenience. According to the U.S. Department of Agriculture, hogs cause approximately $2.5 billion in damages each year by rooting and trampling farm and forest lands, eating crops, and transmitting diseases and parasites.

Control

In the face of this “feral swine bomb,” landowners, governments, experts, and others have responded with a variety of mitigation tactics — to varying success.

One of the most popular

among the public is hunting, which has grown into a common recreational activity and is only lightly regulated in many states. However, the strategy has limited effectiveness, as hogs often relocate in response to hunting pressure.

Fencing and trapping tend to be the most effective, but require more upkeep and investment to work well at scale.

And while there has been extensive research into pharmaceutical controls, the U.S. currently has no approved legal poisons for hogs.

As the wild hog problem continues to grow, some states will face greater challenges than others. While states like California and Hawaii have fairly large feral hog populations, wild hogs are unquestionably most common in the southern U.S.

Most states in the South have experienced hog sightings in at least 90% of their counties, and collectively southern states are responsible for the overwhelming majority of feral hog reports.

To determine the states with the biggest wild hog problem, researchers calculated the number of feral hog sightings reported in each state. In the event of a tie, the state with the greater percentage of counties with feral hogs was ranked higher.