I don't think I've ever seen a gopher in Pa. We used to shoot them with BB/pellet guns and the .22 in Minnesota. If we couldn't find any, we did what you'd see in a cartoon and ran a garden hose down the hole and flooded them out. I was like 8 or 9 years old at the time. We also would use traps, the kind you would use for muskrats, not your traps you use for live trapping, and just turn them upside down over the hole so when they came out, it snapped right on their necks. Seemed to work well, never saw one struggle.
http://www.schmittent.com/webpic-Mon...1.5%20trap.jpg