The Illinois Feral Swine Damage Management Program – What is the Current Feral Swine Population Status in our State?

Photos courtesy of the author.

A collaborative effort that began in 2011, involving the U.S. Department of Agriculture’s Wildlife Services (USDA-WS) program and Illinois Department of Natural Resources (IDNR), resulted in the apparent elimination of feral swine in the state. Earlier this year, reports from the public and other agencies suggested the presence of a small, isolated feral swine population in one of our most-southern counties. An invasive species, feral swine, also known as wild hogs, can cause damage to diverse resources wherever they are found.

The Illinois landscape contains ideal habitat for feral swine with adequate forest cover and abundant food sources both in acorns and agricultural crops. The first feral swine population in Illinois was confirmed in 2009 among an approximately 28 square mile area in Fulton County. An additional population was discovered just a few years later among an area approximately 31 square miles in size encompassing the counties of Fayette, Marion, Effingham and Clay.

To address the feral swine problem in Illinois and to protect wildlife, wildlife habitat, agriculture, livestock and human health and safety, USDA-WS and IDNR developed a collaborative feral swine damage management program in 2011.

The population and range of feral swine has rapidly increased across the nation. In the U.S., feral swine have expanded from a small percentage of counties in 17 states in 1982 to at least 35 states in 2019. Feral swine can carry at least 30 viral and bacterial diseases, and nearly 40 types of parasites that can affect humans, domestic livestock and wildlife including threatened and endangered species. Feral swine compete directly with our native wildlife for both food resources and habitat. They may prey on native wildlife, including ground nesting bird eggs, newborn rabbits and white-tailed deer fawns. Feral swine also contribute to the degradation of watersheds, soil and croplands. Annual costs of feral swine damages and the cost to control these damages is estimated to exceed $1.5 billion nationwide, with more than half directly impacting agriculture. These estimates do not include the cost of damages impacted upon natural resources. Those damages are still not fully understood, and it is difficult to determine a specific dollar value for natural ecosystems and native wildlife.

In 2014 the USDA-WS established a nationwide program in response to the rapid expansion and increased damages and disease threats posed by these non-native animals. The program target is to significantly reduce and, where possible, eliminate feral swine populations throughout the United States. The National Feral Swine Damage Management Program is the first nationally coordinated effort aimed at reducing damage and disease threats posed by feral swine.

Through strategic, collaborative efforts, using an integrated damage management program, the USDA-WS and IDNR successfully eliminated feral swine populations in Fulton County and the adjoining counties of Fayette, Marion, Effingham and Clay by the spring of 2016.

After eliminating those known populations, USDA-WS and IDNR continues to investigate reports of the invasive mammal received from throughout the state. On average, USDA-WS and IDNR investigates nearly 50 reports of feral swine each year. Most reports are the result of recently escaped/loose domestic swine including a variety of potbelly breeds of swine. Most of these swine return to captivity quickly and do not result in self-sustaining breeding populations. However, in 2016 a small and isolated population of feral swine was discovered in Pike County. This population resulted from free-range practices with domestic swine and nearly non-existent fencing. Swine roaming free upon thousands of acres of neighboring properties resulted in reports of the swine venturing as far away as five miles from their source, and extensive property and cropland damage. After significant public outreach and coordination with numerous stakeholders, private landowners and local law enforcement, the USDA-WS and IDNR began surveillance and elimination efforts in 2018. As of 2019 this population has been successfully eliminated. Surveillance of this area will continue among for two more years to ensure no feral swine remain in order to prevent re-establishment of this population. Private landowners have been pleased with the management efforts and in protecting their properties, native wildlife habitat and croplands.

More recently in 2019, reports from the public, stakeholders, and the U.S. Forest Service has led to the discovery of a potential emergent feral swine population in Pope County. USDA-WS and IDNR have begun working with numerous stakeholders and private landowners in this county in order to better understand the size and geographic distribution of this feral swine population as ground surveillance and elimination efforts begin.

To report feral swine sightings or learn more about this invasive animal and the damage they cause, contact USDA-WS at 1-866-4-USDA-WS.

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Brad Wilson is a wildlife biologist with the USDA APHIS Wildlife Services in Illinois.