Selective depredation of planted hardwood seedlings by wild pigs in a wetland restoration area

摘要

Following the planting of several thousand hardwood seedlings in a 69-ha wetland restoration area in west-central South Carolina, USA, wild pigs (Sus scrofa) depredated a large percentage of the young trees. This planting was undertaken as part of a mitigation effort to restore a bottomland hardwood community in the corridor and delta of a third order stream that had been previously impacted by the discharge of heated nuclear reactor effluent. The depredated restoration areas had been pretreated with both herbicide and control burning prior to planting the hardwod seedlings. After discovery of the wild pig damage, these areas were surveyed on foot to assess the magnitude of the depredation on the planted seedling crop. Foraging by the local wild pigs in the pretreatment areas selectively impacted only four of the nine hardwod species used in this restoration effort. Based on the surveys, the remaining five species did not appear to have been impacted at all. A variety of reasons could be used to explain this phenomenon. The pretreatment methodolgy is thought to have been the primary aspect of the restoration program that initially led the wild pigs to discover the planted seedlings. In addition, it is possible that a combination of other factors associated with odor and taste may have resulted in the selective depredation. Future wetland restoration efforts in areas with wild pigs should consider pretreatment methods and species to be planted. If pretreatment methods and species such as discussed in the present study must be used, Then the prior removal of wild pigs from surrounding lands will help prevent depredations by this non-native species.