College of Agriculture & Natural Resources

A new study will pair Michigan State University (MSU) researchers with researchers from the University of Michigan-Flint to learn more about one of the state’s most potentially destructive invasive species: feral swine.

The approximately $500,000 grant from the Michigan Department of Natural Resources (MDNR) also pulls in resources from the U.S. Department of Agriculture (USDA).

“To eradicate feral swine from Michigan, we need to develop a better understanding of their ecology -- specifically, how they use and disperse through landscapes,” said Gary Roloff, associate professor in the MSU Department of Fisheries and Wildlife.

 He is co-leader on the grant with Robert Montgomery, also an assistant professor in the Department of Fisheries and Wildlife.

The study involves trapping and collaring up to 18 feral swine in the central Lower Peninsula to get a better idea of their hourly, daily and seasonal movements, and habitat use patterns in the state. Another aspect of the project is to quantify agricultural and environmental damage caused by feral swine.

This summer, researchers honed their trapping and collaring skills on a single feral swine. Roloff said that researchers were interested in testing the collaring process, the collar design and the fit of the collar on the swine.  A large trapping effort to catch 17 to 18 more pigs will start in January 2015.

During the five-year project, MSU researchers will measure the location and extent of feral swine rooting activities (ecological and agricultural damage) and movement, develop a predictive model of how feral swine use habitat and evaluate the efficacy of techniques for controlling feral swine populations.

Researchers from the University of Michigan-Flint will monitor swine for the presence of diseases and parasites, as well as potential disease transmission routes from feral swine to wildlife, livestock and humans. Feral swine are known to carry diseases that could have negative consequences on Michigan’s pork industry if they’re transmitted from feral to domestic swine.

“Traditionally, the MDNR might look to universities to help assess a few aspects of species ecology to assist with management.  However, given the potential for irreversible ecological impacts if feral swine become widespread throughout Michigan, we believed it was critical to gain extensive knowledge about them immediately to develop effective control strategies,” said Dwayne Etter, MDNR wildlife biologist.

Roloff said feral swine have been observed statewide.

“By the end of 2011, feral swine were known to occur in 72 of the 83 counties in Michigan, and in areas with highly localized populations, they not only have negative impacts on crop production but also present a potential risk of spreading diseases to domestic swine, other livestock and wildlife,” Roloff said. “Feral swine also pose significant threats to the state’s wildlife. We are just beginning to understand the indirect impacts of feral swine on naturally occurring plant and animal communities.”

Karmen Hollis, a wildlife epidemiologist at the University of Michigan-Flint, will focus on disease progression in feral swine and how diseases are transmitted from feral swine to livestock and some wildlife.

Roloff said that one of the main reasons for the Michigan research is that most of the information available on feral swine in the United States is based on Southern studies. 

“The feral swine in Michigan that are the focus of our research are the pure Russian boar breed.  Hybrid swine tend to be more common in the South. Given the different breed, climate and environmental conditions in more northern latitudes, the MDNR believed it worthwhile to fund the study,” Roloff said.

“We have several questions to answer that will ultimately help us control feral swine more efficiently,” Roloff said.

Those questions include:

• How do feral swine respond to severe winters? Do they move into denser cover, or do they move closer to domestic facilities, potentially increasing interactions with livestock?
• Are there times of the year when groups might be particularly vulnerable to control?

“By working with landowners, farmers, the DNR, the USDA and one another, we will learn a lot more about this species,” Roloff said.

Etter agreed and said that the universities will play a key role in helping eradicate feral swine from Michigan.

“Working collectively with multiple universities and the USDA ensures that we have a broad scope of skills and knowledge to address this critical threat to Michigan’s natural resources,” Etter said. “Given the elusiveness and reproductive potential of feral swine, the window of opportunity to eradicate them from Michigan is brief.”

This work is also supported by the Michigan Pork Producers Association and the Michigan Involvement Committee of Safari Club International.