Proximity to bait and social interactions influence individual wild pig ( Sus scrofa ) visitation at bait sites

Human–wildlife interactions and conflicts with pest species (native and invasive) are a growing problem worldwide, leading to a need for improved management tools and approaches. Wild pigs ( Sus scrofa ) are extensively managed as a pest in both their native and invasive range, with the goal of population reduction or eradication to mitigate damage to native and anthropogenic ecosystems. Management programs for wild pigs often use a variety of tools (e.g., remote cameras, traps, shooting, and toxic bait) that require attracting individuals to a location with bait. However, not all bait sites are visited by wild pigs, and it is often unknown why individuals locate some bait sites but not others. We conducted 325 experimental bait site replicates on 52 collared individual wild pigs in South Carolina, USA, to test the hypothesis that wild pig visitation to bait sites was influenced by a combination of intrinsic (sex, space use) and extrinsic (bait placement methods, addition of scent lure, presence of other wild pigs) factors. We found that target wild pigs visited 30.6% more sites and 33.4 hours faster when bait sites were placed within areas of more concentrated use rather than the periphery of their home ranges. Further, a target animal was more likely to find a bait site and had reduced times to detection when they were nearer to bait at the time of deployment. However, females visited 28.3% fewer sites and took 118.9 hours longer to locate bait when an adult male visited the site prior to them compared to when an adult male did not, suggesting potential exclusion or avoidance behaviors at bait. The addition of scent or presentation method of bait did not influence visitation rates, suggesting the location of bait on the landscape was the most important factor for enticing wild pigs to visit. Collectively, these results add to the growing body of evidence that the location of bait on the landscape relative to the distribution of wild pigs is critical to optimizing detection, and scents or placement methods cannot overcome poorly located bait sites. Further, managers should consider that the presence of adult males may reduce the likelihood of female or sounder visitation at sites.