I've seen them clear a chicken farm of rats in about a week. No porcupines here but I know they're in the Poconos and that's not far from me at all. 1st time I heard one I thought there was a kid lost in the woods. They also seem to be close to the lakes and rivers around here. Had one about 2 years ago walk out the woods and along my fence at night and kept screaming at my dogs, who were going nuts, for about 100 yards before it veered off