UNDERSTANDING RESOURCE SELECTION, RESOURCE USE, AND LANDSCAPE CONNECTIVITY FOR INVASIVE WILD PIGS (SUS SCROFA) IN THE PRAIRIES: IMPLICATIONS FOR MANAGEMENT

Abstract

The ability to understand habitat selection and movement of invasive species has important practical and theoretical implications. Ecological research is essential for understanding ecological and economic damages to native habitats, wildlife, livestock, and agriculture. Wild pigs were introduced to the western Canada in 1980s, but our understanding of their habitat requirements is largely unknown. I used GPS collar data from invasive wild pigs to elucidate habitat requirements at three temporal scales within the western Canadian agro-ecosystem and to assess regional connectivity across the prairie ecoregion and international boundaries. Crops were at risk to damage at night and once fully ripened, especially corn, which showed consistent selection daily and seasonally. Crop use and selection corresponded to times when anthropogenic pressure was lowest, and crops provided the greatest hiding cover and energetic value; while forests provided cover, thermoregulatory capacity, and food throughout the entirety of the study period. These trends indicated that at finer temporal scales wild pigs emphasized short term needs while over coarser scales they prioritized habitats that serve multiple functional roles. Furthermore, when I used annual selection tendencies to examine potential wild pig expansion, I measured a high degree of connectivity across the prairie ecoregion of Canada and the United States due to the abundance of a forest-crop-wetland landscape which facilitated movement potential. Additionally, areas of habitat homogenization and those without forests restricted movement allowing for the identification of four movement pinch points which could be monitored for wild pig spread. My research demonstrates that: i) agricultural crops are at greater threat to damages than previously observed or reported and ii) the northern United States is at substantial risk of invasion and this has important implications for the spread of wild pigs. Overall, crops play an important role ecologically to wild pigs in Canada, they offer high quality food sources, hiding cover, and impact potential expansion. These results can be used by land managers to identify when and where wild pigs are most likely to be found and to facilitate targeted population reductions in Canadian and United States agro-ecosystems aimed to slow expansion to new areas in North America.