Laurie Baratti | (TNS) TravelPulse Encounters between humans and wildlife are becoming increasingly common, particularly in U.S. national parks, where visitor numbers continue to rise. Yellowstone, for instance, saw more than 4.5 million visitors last year alone, according to The Washington Post. The National Park Service’s (NPS) guidance dictates that people should stay at least 25 to 100 yards away from wild animals, with the exact distance dependent on the species.