Under the new rule, feral swine can be taken legally in the following manners in Illinois:
1. Hunters, who are legally deer hunting during firearm deer seasons, will be able to legally shoot feral swine. They will also be required to report the harvest of feral swine during firearm deer seasons to the IDNR. Hunters are asked to report feral swine harvest to Doug Dufford, IDNR Wildlife Disease and Invasive Animals Program Manager, at (815) 369-2414. Hunters who legally harvest feral swine are able to keep the meat if they desire.
2. It is now illegal to guide or be an outfitter for feral swine hunting. It is also illegal to hunt feral swine in an enclosure.
3. Landowners are required to obtain a nuisance wildlife permit if they see feral swine on their property and want to personally remove the swine outside of the “gun” deer seasons, or they can contact IDNR staff for assistance in removing feral swine at no charge to the landowner.
***Looks like they covered things pretty well in #2 to me to keep them from doing what you mentioned.