Classroom Questions Questions for ‘Can anything stop the big pig invasion?’ Feral pigs roam in most U.S. states. New traps may help control the size of their populations. USDA APHIS photo by Clint Turnage/Flickr (CC BY 2.0) Share this:FacebookTwitterRedditGoogle ClassroomEmailPrint By Science News for Students April 19, 2018 at 5:30 am Classroom questions are available for free with registration. Learn more Register to access: Client key* E-mail* Log in Already Registered? Enter your e-mail address above.