Invasion ecology of wild pigs (Sus scrofa) in Florida, USA: the role of humans in the expansion and colonization of an invasive wild ungulate

Biological Invasions

Corresponding author: Samantha M. Wisely,

Summary author: Leah Crone,

Wild pigs, an invasive species, adversely affect local ecosystems and are a pressing issue globally. Invasive species disrupt an environment’s natural cycle by depleting local vegetation and contributing to soil erosion.  This creates undue stress and puts a burden on the area. The abundance and distribution of wild pigs have greatly expanded since being introduced to the continental United States by 16th century explorers. Several factors, including wild pigs’ adaptability to various environments, and intentional introduction of wild pigs for game hunting (a type of human-assisted movement), have contributed to the establishment of wild pig populations in 44 states. To better understand the factors that influence population dispersal, a team including CEID member Stacy Lance conducted a study on population genetic techniques to understand wild pig’s movement across Florida. Researchers collected 482 blood, hair, and kidney samples from 39 different sites and collected demographic data including age, sex, and location. Through genetic testing, they were able to identify genetically distinct subpopulations, as well as individuals whose genetic data indicate mixing between subpopulations. About half of the locations showed intermediate levels of genetic differentiation in contrast to other locations. The researchers concluded that the distribution of wild pigs throughout Florida was highly impacted by human-assisted movement. The genetic patterns found in the samples would be difficult to explain if natural dispersal was the contributing factor. Researchers cited a number of human-driven factors contributing to range expansion. Escapes from wildlife holding facilities may introduce wild pig populations to new environments. There is also speculation that illegal transport and release of pigs is a driving factor. This research illuminates human’s role in the spread of invasive species.  While this particular study focused on wild pigs throughout Florida, it is likely similar human-driven activities influence invasive species to spread globally. This research will help to inform legislative and regularly policy concerning the management of invasive wild pigs.

Hernández, F.A et al. (2018). Invasion ecology of wild pigs (Sus scrofa) in Florida, USA: the role of humans in the expansion and colonization of an invasive wild ungulate. Biological Invasions, 20(7): 1865-1880.

Photo Credit: “Ausgewachsenes Wildschwein beim Suhlen” by 4028mdk09 licensed under CC BY-SA 3.0