Author: Lauren Hildreth
Published: November 27, 2018
On a warm June day, a crew of MDC biologists traveled to document a population of Mead’s milkweed, an endangered plant.
Like other milkweeds, Mead’s serves as critical habitat for the monarch butterfly and other pollinators vitally important to agriculture and wildlife. This population occurs on a remote glade, a unique type of desertlike habitat, in the shadow of Taum Sauk Mountain. The glade holds the largest Mead’s milkweed population in Missouri and one of only a few healthy populations remaining in the world. As the biologists walked into the glade, they saw many milkweed flowers but soon noticed damage around the area. Dozens of the milkweed lay strewn about. The biologists looked at each other. “Hogs,” they said, almost in unison. Feral hogs, a destructive invasive pest, had not decimated the entire milkweed population — this time. But, until feral hogs are eliminated, this rare plant population will remain vulnerable to their destruction.
DESTRUCTIVE, DANGEROUS, AND COSTLY
Feral hogs are invasive pests that need to be eliminated from Missouri. A sounder, or group, of hogs can demolish a crop field in one night. The U.S. Department of Agriculture (USDA) estimated that feral hogs cause $1.5 billion in damage nationwide every year. However, that estimate was made 10 years ago, and the feral hog population around the country has only continued to grow.
Feral hogs became an issue in Missouri in the mid-1990s. A few misguided individuals wanted to establish hog populations for hunting, so they illegally released domestic farm hogs around the state. Between natural reproduction and continued illegal releases, the feral hog population exploded in southern Missouri. They now occur in more than 30 Missouri counties. Feral hog damage is widespread, and it shows up in croplands, pastures, and more.
Feral hogs destroy habitats native wildlife depend on, including natural communities like fens, glades, wetlands, and bottomland hardwood forests. Their rooting and wallowing behaviors are the main cause of that destruction. Feral hogs will also eat ground nesting birds and other wildlife, and they eat nuts, roots, berries, and other natural foods that native wildlife need to survive.
Not only do they physically destroy habitats and agricultural land, they also carry diseases. Swine brucellosis and tularemia are two diseases that humans can contract from feral hogs. They also carry pseudorabies, which can be spread to other wildlife as well as domestic hogs, sheep, cattle, and even pets. If these diseases infected Missouri’s domestic swine herd, which is considered disease free, it could devastate the state’s agricultural industry, hurting local economies.
Many States Have Lost the Battle
Hogs are one of the fastest-multiplying mammals. In some cases, they reach breeding age at six months, and a sow can have two litters and up to 18 piglets in a year. This leads to large populations with a rapid growth rate, as high as 166 percent annually. Because of this high reproductive rate, it is difficult to get an accurate estimate of Missouri’s feral hog population. It also makes reducing the population difficult without a strategic and scientific approach.
From what we’ve seen in Missouri and in other states, we know that hunting is not effective at eliminating feral hogs. Here in Missouri, a shoot-on-sight strategy was encouraged for over 20 years. During that time, the feral hog population continued to grow. Allowing hunting of feral hogs can lead to illegal releases, tempting some misguided individuals to establish new populations. Tennessee witnessed this firsthand.
For 50 years, Tennessee did not allow hunting of feral hogs in any part of the state. There were two isolated populations around fenced hunting preserves, likely escaped hogs from those facilities.
In 1999, a statewide hog season was started on public and private land. Over the next 10 years, populations of feral hogs popped up across the entire state, and the suspected cause of this spread was intentional releases for hunting. This example shows that hunting creates an incentive for people to release feral hogs into new areas. In 2011, Tennessee changed regulations, no longer listed feral hogs as a game species, and banned hog hunting around the state. They are now seeing success with reducing populations.
Landowners in Missouri are Fighting Back
Feral hogs are a serious problem for many Missouri landowners like Lavern Daves of Wayne County. Daves runs a cattle operation on his land. About five years ago, he spotted feral hog wallows on his field edges. At first, he wasn’t too concerned, but then they “swarmed like bees, they were all over the place,” Daves said. He immediately reached out to MDC to come trap the hogs. Staff used a drop trap at several locations and, over time, they have removed more than 50 hogs from his property. In addition to the damage to his land, Daves noticed that feral hogs “are really hard on young deer and on turkey nests.” His advice to landowners that find themselves with feral hog damage? “As soon as you see sign, call MDC to come trap.”
Jeff Hawk, who owns property in Iron County that he manages for recreation, has a slightly different story. He saw hogs around the same time as Daves, about four or five years ago.
He spotted them with game cameras, and he saw tracks and rooting on his property. One January, he even noticed that there were no acorns left on the ground — the feral hogs had eaten them all. He tried hunting them, but he was unsuccessful, killing only two hogs. Then the population started growing out of control, the peak of destruction occurring in the spring of 2017. He arrived at his property to find one of his fields destroyed by feral hogs. “Nothing we could do would get them under control,” Hawk
said. He picked up the phone and called MDC for help. “They were very responsive and came right out.” MDC staff trapped around 15 hogs, including several pregnant females. He has seen a decrease in the hog population on his property and is quite happy with that. “Feral hogs are an invasive species and take over in nature. They destroy all the food, and native wildlife are highly impacted. They need to be gone.”
Missouri Aims to Put Up a Fight
The state of Missouri has a multi-agency team that is dedicated to eliminating feral hogs inside our borders. The team pursues a coordinated interagency approach, complete with ever-improving tools and technology. “The cornerstone of the Missouri feral hog elimination effort is partnerships,” said Mark McLain, MDC Feral Hog Elimination Team leader. “Partnerships between government agencies, agricultural and environmental groups, and landowners are the key to removing this damaging invasive pest from Missouri.”
The map at left shows where we have seen feral hogs around the state. When citizens report feral hogs, MDC and partners can get an even better idea of where the feral hogs are located. MDC can’t be everywhere at once, so the extra eyes will help increase our knowledge of feral hog distribution. “Without the public’s help, the elimination of feral hogs will be impossible.” McLain said.
More Funding Ups the Odds of Success
With the devastating effects of feral hogs evident in Missouri, MDC committed $1.865 million annually, with Missouri Conservation Commission approval, to eliminate feral hogs around the state. This dedicated funding, initially approved for fiscal year 2018, has increased the number of hog trappers on the landscape. “Hog trappers are always looking ahead. Where will this trap move to next? Where can I get bait out?” McLain explained. With that forward thinking, and the added manpower, more landowners can get the assistance they need to fight feral hogs on their property, and more feral hogs can be trapped on public land as well.
The funding also allows staff and partners to purchase more supplies, including traps and the corn required for baiting those traps. Those two pieces are integral in running a successful operation to rid an area of feral hogs. The more carefully placed traps on the ground, the higher likelihood that a feral hog, or two or 50, will find a trap.
Report — Don’t Shoot!
MDC and its partner agencies are fighting hard against feral hogs, and there are two simple things that you can do to join in the fight. First, report any hog damage you see to MDC as soon as possible. Second, if you see a feral hog in the wild, Report — Don’t Shoot! Call 573-522-4115, ext. 3296 to report a sighting or damage, or report online at mdc.mo.gov/feralhog. With more eyes looking for this invasive pest, Missouri can gain more ground in the fight against feral hogs.
Help eliminate feral hogs.
If you see their signs, call 573-522-4115, ext. 3296.
Testing for Diseases and Origins
The USDA-Wildlife Research Center in Fort Collins, Colorado, processes the feral hog disease testing samples for the state of Missouri. Every year, the lab tests roughly 100 feral hogs taken from around the state for three diseases: classical swine fever (not found in Missouri), swine brucellosis, and pseudorabies (both found in Missouri feral hogs). Using blood samples and the hogs’ ears, which provide genetic material, scientists can determine a variety of things, including where specific animals came from, whether in state or out of state.
Read the story from the Missouri Conservationist Magazine.
© 2018 Missouri Department of Conservation